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authorAndrew Lee <anwlee@google.com>2015-05-11 23:25:31 +0000
committerAndroid Git Automerger <android-git-automerger@android.com>2015-05-11 23:25:31 +0000
commit89cf2cd50347dfda6a4f7662755e669aced5baf1 (patch)
tree12eba3b8e399b48ba29911f27a15a4d117700e14
parent4e4deabd0d9691e48353d10769c3642851fd015b (diff)
parentb06e181b0374a10eb51e970e99df69d3da62d66c (diff)
am b06e181b: Remove unused ViewDragHelper.
* commit 'b06e181b0374a10eb51e970e99df69d3da62d66c': Remove unused ViewDragHelper.
-rw-r--r--src/com/android/dialer/widget/ViewDragHelper.java1574
1 files changed, 0 insertions, 1574 deletions
diff --git a/src/com/android/dialer/widget/ViewDragHelper.java b/src/com/android/dialer/widget/ViewDragHelper.java
deleted file mode 100644
index fe3ab8230..000000000
--- a/src/com/android/dialer/widget/ViewDragHelper.java
+++ /dev/null
@@ -1,1574 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-
-package com.android.dialer.widget;
-
-import android.content.Context;
-import android.support.v4.view.MotionEventCompat;
-import android.support.v4.view.VelocityTrackerCompat;
-import android.support.v4.view.ViewCompat;
-import android.util.Log;
-import android.view.MotionEvent;
-import android.view.VelocityTracker;
-import android.view.View;
-import android.view.ViewConfiguration;
-import android.view.ViewGroup;
-import android.widget.Scroller;
-
-import java.util.Arrays;
-
-/**
- * ViewDragHelper is a utility class for writing custom ViewGroups. It offers a number
- * of useful operations and state tracking for allowing a user to drag and reposition
- * views within their parent ViewGroup.
- */
-public class ViewDragHelper {
- private static final String TAG = "ViewDragHelper";
-
- /**
- * A null/invalid pointer ID.
- */
- public static final int INVALID_POINTER = -1;
-
- /**
- * A view is not currently being dragged or animating as a result of a fling/snap.
- */
- public static final int STATE_IDLE = 0;
-
- /**
- * A view is currently being dragged. The position is currently changing as a result
- * of user input or simulated user input.
- */
- public static final int STATE_DRAGGING = 1;
-
- /**
- * A view is currently settling into place as a result of a fling or
- * predefined non-interactive motion.
- */
- public static final int STATE_SETTLING = 2;
-
- /**
- * Edge flag indicating that the left edge should be affected.
- */
- public static final int EDGE_LEFT = 1 << 0;
-
- /**
- * Edge flag indicating that the right edge should be affected.
- */
- public static final int EDGE_RIGHT = 1 << 1;
-
- /**
- * Edge flag indicating that the top edge should be affected.
- */
- public static final int EDGE_TOP = 1 << 2;
-
- /**
- * Edge flag indicating that the bottom edge should be affected.
- */
- public static final int EDGE_BOTTOM = 1 << 3;
-
- /**
- * Edge flag set indicating all edges should be affected.
- */
- public static final int EDGE_ALL = EDGE_LEFT | EDGE_TOP | EDGE_RIGHT | EDGE_BOTTOM;
-
- /**
- * Indicates that a check should occur along the horizontal axis
- */
- public static final int DIRECTION_HORIZONTAL = 1 << 0;
-
- /**
- * Indicates that a check should occur along the vertical axis
- */
- public static final int DIRECTION_VERTICAL = 1 << 1;
-
- /**
- * Indicates that a check should occur along all axes
- */
- public static final int DIRECTION_ALL = DIRECTION_HORIZONTAL | DIRECTION_VERTICAL;
-
- private static final int EDGE_SIZE = 20; // dp
-
- private static final int BASE_SETTLE_DURATION = 256; // ms
- private static final int MAX_SETTLE_DURATION = 600; // ms
-
- // Current drag state; idle, dragging or settling
- private int mDragState;
-
- // Distance to travel before a drag may begin
- private int mTouchSlop;
-
- // Last known position/pointer tracking
- private int mActivePointerId = INVALID_POINTER;
- private float[] mInitialMotionX;
- private float[] mInitialMotionY;
- private float[] mLastMotionX;
- private float[] mLastMotionY;
- private int[] mInitialEdgesTouched;
- private int[] mEdgeDragsInProgress;
- private int[] mEdgeDragsLocked;
- private int mPointersDown;
-
- private VelocityTracker mVelocityTracker;
- private float mMaxVelocity;
- private float mMinVelocity;
-
- private int mEdgeSize;
- private int mTrackingEdges;
-
- // We need to use a Scroller instead of an OverScroller (b/17700698) and as a result, we need
- // to keep track of the final scroll position ourselves in mFinalScrollY (b/17704016) whenever
- // we programmatically scroll or fling mScroller.
- private Scroller mScroller;
- private int mFinalScrollY;
-
- private final Callback mCallback;
-
- private View mCapturedView;
- private boolean mReleaseInProgress;
-
- private final ViewGroup mParentView;
-
- /**
- * A Callback is used as a communication channel with the ViewDragHelper back to the
- * parent view using it. <code>on*</code>methods are invoked on siginficant events and several
- * accessor methods are expected to provide the ViewDragHelper with more information
- * about the state of the parent view upon request. The callback also makes decisions
- * governing the range and draggability of child views.
- */
- public static abstract class Callback {
- /**
- * Called when the drag state changes. See the <code>STATE_*</code> constants
- * for more information.
- *
- * @param state The new drag state
- *
- * @see #STATE_IDLE
- * @see #STATE_DRAGGING
- * @see #STATE_SETTLING
- */
- public void onViewDragStateChanged(int state) {}
-
- /**
- * Called when the captured view's position changes as the result of a drag or settle.
- *
- * @param changedView View whose position changed
- * @param left New X coordinate of the left edge of the view
- * @param top New Y coordinate of the top edge of the view
- * @param dx Change in X position from the last call
- * @param dy Change in Y position from the last call
- */
- public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {}
-
- /**
- * Called when a child view is captured for dragging or settling. The ID of the pointer
- * currently dragging the captured view is supplied. If activePointerId is
- * identified as {@link #INVALID_POINTER} the capture is programmatic instead of
- * pointer-initiated.
- *
- * @param capturedChild Child view that was captured
- * @param activePointerId Pointer id tracking the child capture
- */
- public void onViewCaptured(View capturedChild, int activePointerId) {}
-
- /**
- * Called when the child view is no longer being actively dragged.
- * The fling velocity is also supplied, if relevant. The velocity values may
- * be clamped to system minimums or maximums.
- *
- * <p>Calling code may decide to fling or otherwise release the view to let it
- * settle into place. It should do so using {@link #settleCapturedViewAt(int, int)}
- * or {@link #flingCapturedView(int, int, int, int)}. If the Callback invokes
- * one of these methods, the ViewDragHelper will enter {@link #STATE_SETTLING}
- * and the view capture will not fully end until it comes to a complete stop.
- * If neither of these methods is invoked before <code>onViewReleased</code> returns,
- * the view will stop in place and the ViewDragHelper will return to
- * {@link #STATE_IDLE}.</p>
- *
- * @param releasedChild The captured child view now being released
- * @param xvel X velocity of the pointer as it left the screen in pixels per second.
- * @param yvel Y velocity of the pointer as it left the screen in pixels per second.
- */
- public void onViewReleased(View releasedChild, float xvel, float yvel) {}
-
- /**
- * Called when the child view has been released with a fling.
- *
- * <p>Calling code may decide to fling or otherwise release the view to let it
- * settle into place.</p>
- *
- * @param releasedChild The captured child view now being released
- * @param xvel X velocity of the fling.
- * @param yvel Y velocity of the fling.
- */
- public void onViewFling(View releasedChild, float xvel, float yvel) {}
-
- /**
- * Called when one of the subscribed edges in the parent view has been touched
- * by the user while no child view is currently captured.
- *
- * @param edgeFlags A combination of edge flags describing the edge(s) currently touched
- * @param pointerId ID of the pointer touching the described edge(s)
- * @see #EDGE_LEFT
- * @see #EDGE_TOP
- * @see #EDGE_RIGHT
- * @see #EDGE_BOTTOM
- */
- public void onEdgeTouched(int edgeFlags, int pointerId) {}
-
- /**
- * Called when the given edge may become locked. This can happen if an edge drag
- * was preliminarily rejected before beginning, but after {@link #onEdgeTouched(int, int)}
- * was called. This method should return true to lock this edge or false to leave it
- * unlocked. The default behavior is to leave edges unlocked.
- *
- * @param edgeFlags A combination of edge flags describing the edge(s) locked
- * @return true to lock the edge, false to leave it unlocked
- */
- public boolean onEdgeLock(int edgeFlags) {
- return false;
- }
-
- /**
- * Called when the user has started a deliberate drag away from one
- * of the subscribed edges in the parent view while no child view is currently captured.
- *
- * @param edgeFlags A combination of edge flags describing the edge(s) dragged
- * @param pointerId ID of the pointer touching the described edge(s)
- * @see #EDGE_LEFT
- * @see #EDGE_TOP
- * @see #EDGE_RIGHT
- * @see #EDGE_BOTTOM
- */
- public void onEdgeDragStarted(int edgeFlags, int pointerId) {}
-
- /**
- * Called to determine the Z-order of child views.
- *
- * @param index the ordered position to query for
- * @return index of the view that should be ordered at position <code>index</code>
- */
- public int getOrderedChildIndex(int index) {
- return index;
- }
-
- /**
- * Return the magnitude of a draggable child view's horizontal range of motion in pixels.
- * This method should return 0 for views that cannot move horizontally.
- *
- * @param child Child view to check
- * @return range of horizontal motion in pixels
- */
- public int getViewHorizontalDragRange(View child) {
- return 0;
- }
-
- /**
- * Return the magnitude of a draggable child view's vertical range of motion in pixels.
- * This method should return 0 for views that cannot move vertically.
- *
- * @param child Child view to check
- * @return range of vertical motion in pixels
- */
- public int getViewVerticalDragRange(View child) {
- return 0;
- }
-
- /**
- * Called when the user's input indicates that they want to capture the given child view
- * with the pointer indicated by pointerId. The callback should return true if the user
- * is permitted to drag the given view with the indicated pointer.
- *
- * <p>ViewDragHelper may call this method multiple times for the same view even if
- * the view is already captured; this indicates that a new pointer is trying to take
- * control of the view.</p>
- *
- * <p>If this method returns true, a call to {@link #onViewCaptured(android.view.View, int)}
- * will follow if the capture is successful.</p>
- *
- * @param child Child the user is attempting to capture
- * @param pointerId ID of the pointer attempting the capture
- * @return true if capture should be allowed, false otherwise
- */
- public abstract boolean tryCaptureView(View child, int pointerId);
-
- /**
- * Restrict the motion of the dragged child view along the horizontal axis.
- * The default implementation does not allow horizontal motion; the extending
- * class must override this method and provide the desired clamping.
- *
- *
- * @param child Child view being dragged
- * @param left Attempted motion along the X axis
- * @param dx Proposed change in position for left
- * @return The new clamped position for left
- */
- public int clampViewPositionHorizontal(View child, int left, int dx) {
- return 0;
- }
-
- /**
- * Restrict the motion of the dragged child view along the vertical axis.
- * The default implementation does not allow vertical motion; the extending
- * class must override this method and provide the desired clamping.
- *
- *
- * @param child Child view being dragged
- * @param top Attempted motion along the Y axis
- * @param dy Proposed change in position for top
- * @return The new clamped position for top
- */
- public int clampViewPositionVertical(View child, int top, int dy) {
- return 0;
- }
- }
-
- private final Runnable mSetIdleRunnable = new Runnable() {
- public void run() {
- setDragState(STATE_IDLE);
- }
- };
-
- /**
- * Factory method to create a new ViewDragHelper.
- *
- * @param forParent Parent view to monitor
- * @param cb Callback to provide information and receive events
- * @return a new ViewDragHelper instance
- */
- public static ViewDragHelper create(ViewGroup forParent, Callback cb) {
- return new ViewDragHelper(forParent.getContext(), forParent, cb);
- }
-
- /**
- * Factory method to create a new ViewDragHelper.
- *
- * @param forParent Parent view to monitor
- * @param sensitivity Multiplier for how sensitive the helper should be about detecting
- * the start of a drag. Larger values are more sensitive. 1.0f is normal.
- * @param cb Callback to provide information and receive events
- * @return a new ViewDragHelper instance
- */
- public static ViewDragHelper create(ViewGroup forParent, float sensitivity, Callback cb) {
- final ViewDragHelper helper = create(forParent, cb);
- helper.mTouchSlop = (int) (helper.mTouchSlop * (1 / sensitivity));
- return helper;
- }
-
- /**
- * Apps should use ViewDragHelper.create() to get a new instance.
- * This will allow VDH to use internal compatibility implementations for different
- * platform versions.
- *
- * @param context Context to initialize config-dependent params from
- * @param forParent Parent view to monitor
- */
- private ViewDragHelper(Context context, ViewGroup forParent, Callback cb) {
- if (forParent == null) {
- throw new IllegalArgumentException("Parent view may not be null");
- }
- if (cb == null) {
- throw new IllegalArgumentException("Callback may not be null");
- }
-
- mParentView = forParent;
- mCallback = cb;
-
- final ViewConfiguration vc = ViewConfiguration.get(context);
- final float density = context.getResources().getDisplayMetrics().density;
- mEdgeSize = (int) (EDGE_SIZE * density + 0.5f);
-
- mTouchSlop = vc.getScaledTouchSlop();
- mMaxVelocity = vc.getScaledMaximumFlingVelocity();
- mMinVelocity = vc.getScaledMinimumFlingVelocity();
- mScroller = new Scroller(context);
- }
-
- /**
- * Set the minimum velocity that will be detected as having a magnitude greater than zero
- * in pixels per second. Callback methods accepting a velocity will be clamped appropriately.
- *
- * @param minVel Minimum velocity to detect
- */
- public void setMinVelocity(float minVel) {
- mMinVelocity = minVel;
- }
-
- /**
- * Return the currently configured minimum velocity. Any flings with a magnitude less
- * than this value in pixels per second. Callback methods accepting a velocity will receive
- * zero as a velocity value if the real detected velocity was below this threshold.
- *
- * @return the minimum velocity that will be detected
- */
- public float getMinVelocity() {
- return mMinVelocity;
- }
-
- /**
- * Retrieve the current drag state of this helper. This will return one of
- * {@link #STATE_IDLE}, {@link #STATE_DRAGGING} or {@link #STATE_SETTLING}.
- * @return The current drag state
- */
- public int getViewDragState() {
- return mDragState;
- }
-
- /**
- * Enable edge tracking for the selected edges of the parent view.
- * The callback's {@link Callback#onEdgeTouched(int, int)} and
- * {@link Callback#onEdgeDragStarted(int, int)} methods will only be invoked
- * for edges for which edge tracking has been enabled.
- *
- * @param edgeFlags Combination of edge flags describing the edges to watch
- * @see #EDGE_LEFT
- * @see #EDGE_TOP
- * @see #EDGE_RIGHT
- * @see #EDGE_BOTTOM
- */
- public void setEdgeTrackingEnabled(int edgeFlags) {
- mTrackingEdges = edgeFlags;
- }
-
- /**
- * Return the size of an edge. This is the range in pixels along the edges of this view
- * that will actively detect edge touches or drags if edge tracking is enabled.
- *
- * @return The size of an edge in pixels
- * @see #setEdgeTrackingEnabled(int)
- */
- public int getEdgeSize() {
- return mEdgeSize;
- }
-
- /**
- * Capture a specific child view for dragging within the parent. The callback will be notified
- * but {@link Callback#tryCaptureView(android.view.View, int)} will not be asked permission to
- * capture this view.
- *
- * @param childView Child view to capture
- * @param activePointerId ID of the pointer that is dragging the captured child view
- */
- public void captureChildView(View childView, int activePointerId) {
- if (childView.getParent() != mParentView) {
- throw new IllegalArgumentException("captureChildView: parameter must be a descendant " +
- "of the ViewDragHelper's tracked parent view (" + mParentView + ")");
- }
-
- mCapturedView = childView;
- mActivePointerId = activePointerId;
- mCallback.onViewCaptured(childView, activePointerId);
- setDragState(STATE_DRAGGING);
- }
-
- /**
- * @return The currently captured view, or null if no view has been captured.
- */
- public View getCapturedView() {
- return mCapturedView;
- }
-
- /**
- * @return The ID of the pointer currently dragging the captured view,
- * or {@link #INVALID_POINTER}.
- */
- public int getActivePointerId() {
- return mActivePointerId;
- }
-
- /**
- * @return The minimum distance in pixels that the user must travel to initiate a drag
- */
- public int getTouchSlop() {
- return mTouchSlop;
- }
-
- /**
- * The result of a call to this method is equivalent to
- * {@link #processTouchEvent(android.view.MotionEvent)} receiving an ACTION_CANCEL event.
- */
- public void cancel() {
- mActivePointerId = INVALID_POINTER;
- clearMotionHistory();
-
- if (mVelocityTracker != null) {
- mVelocityTracker.recycle();
- mVelocityTracker = null;
- }
- }
-
- /**
- * {@link #cancel()}, but also abort all motion in progress and snap to the end of any
- * animation.
- */
- public void abort() {
- cancel();
- if (mDragState == STATE_SETTLING) {
- final int oldX = mScroller.getCurrX();
- final int oldY = mScroller.getCurrY();
- mScroller.abortAnimation();
- final int newX = mScroller.getCurrX();
- final int newY = mScroller.getCurrY();
- mCallback.onViewPositionChanged(mCapturedView, newX, newY, newX - oldX, newY - oldY);
- }
- setDragState(STATE_IDLE);
- }
-
- /**
- * Animate the view <code>child</code> to the given (left, top) position.
- * If this method returns true, the caller should invoke {@link #continueSettling(boolean)}
- * on each subsequent frame to continue the motion until it returns false. If this method
- * returns false there is no further work to do to complete the movement.
- *
- * <p>This operation does not count as a capture event, though {@link #getCapturedView()}
- * will still report the sliding view while the slide is in progress.</p>
- *
- * @param child Child view to capture and animate
- * @param finalLeft Final left position of child
- * @param finalTop Final top position of child
- * @return true if animation should continue through {@link #continueSettling(boolean)} calls
- */
- public boolean smoothSlideViewTo(View child, int finalLeft, int finalTop) {
- mCapturedView = child;
- mActivePointerId = INVALID_POINTER;
-
- return forceSettleCapturedViewAt(finalLeft, finalTop, 0, 0);
- }
-
- /**
- * Settle the captured view at the given (left, top) position.
- * The appropriate velocity from prior motion will be taken into account.
- * If this method returns true, the caller should invoke {@link #continueSettling(boolean)}
- * on each subsequent frame to continue the motion until it returns false. If this method
- * returns false there is no further work to do to complete the movement.
- *
- * @param finalLeft Settled left edge position for the captured view
- * @param finalTop Settled top edge position for the captured view
- * @return true if animation should continue through {@link #continueSettling(boolean)} calls
- */
- public boolean settleCapturedViewAt(int finalLeft, int finalTop) {
- if (!mReleaseInProgress) {
- throw new IllegalStateException("Cannot settleCapturedViewAt outside of a call to " +
- "Callback#onViewReleased");
- }
-
- return forceSettleCapturedViewAt(finalLeft, finalTop,
- (int) VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
- (int) VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId));
- }
-
- /**
- * Settle the captured view at the given (left, top) position.
- *
- * @param finalLeft Target left position for the captured view
- * @param finalTop Target top position for the captured view
- * @param xvel Horizontal velocity
- * @param yvel Vertical velocity
- * @return true if animation should continue through {@link #continueSettling(boolean)} calls
- */
- private boolean forceSettleCapturedViewAt(int finalLeft, int finalTop, int xvel, int yvel) {
- final int startLeft = mCapturedView.getLeft();
- final int startTop = mCapturedView.getTop();
- final int dx = finalLeft - startLeft;
- final int dy = finalTop - startTop;
-
- if (dx == 0 && dy == 0) {
- // Nothing to do. Send callbacks, be done.
- mScroller.abortAnimation();
- setDragState(STATE_IDLE);
- return false;
- }
-
- final int duration = computeSettleDuration(mCapturedView, dx, dy, xvel, yvel);
- mScroller.startScroll(startLeft, startTop, dx, dy, duration);
- mFinalScrollY = startTop + dy;
-
- setDragState(STATE_SETTLING);
- return true;
- }
-
- private int computeSettleDuration(View child, int dx, int dy, int xvel, int yvel) {
- xvel = clampMag(xvel, (int) mMinVelocity, (int) mMaxVelocity);
- yvel = clampMag(yvel, (int) mMinVelocity, (int) mMaxVelocity);
- final int absDx = Math.abs(dx);
- final int absDy = Math.abs(dy);
- final int absXVel = Math.abs(xvel);
- final int absYVel = Math.abs(yvel);
- final int addedVel = absXVel + absYVel;
- final int addedDistance = absDx + absDy;
-
- final float xweight = xvel != 0 ? (float) absXVel / addedVel :
- (float) absDx / addedDistance;
- final float yweight = yvel != 0 ? (float) absYVel / addedVel :
- (float) absDy / addedDistance;
-
- int xduration = computeAxisDuration(dx, xvel, mCallback.getViewHorizontalDragRange(child));
- int yduration = computeAxisDuration(dy, yvel, mCallback.getViewVerticalDragRange(child));
-
- return (int) (xduration * xweight + yduration * yweight);
- }
-
- private int computeAxisDuration(int delta, int velocity, int motionRange) {
- if (delta == 0) {
- return 0;
- }
-
- final int width = mParentView.getWidth();
- final int halfWidth = width / 2;
- final float distanceRatio = Math.min(1f, (float) Math.abs(delta) / width);
- final float distance = halfWidth + halfWidth *
- distanceInfluenceForSnapDuration(distanceRatio);
-
- int duration;
- velocity = Math.abs(velocity);
- if (velocity > 0) {
- duration = 4 * Math.round(1000 * Math.abs(distance / velocity));
- } else {
- final float range = (float) Math.abs(delta) / motionRange;
- duration = (int) ((range + 1) * BASE_SETTLE_DURATION);
- }
- return Math.min(duration, MAX_SETTLE_DURATION);
- }
-
- /**
- * Clamp the magnitude of value for absMin and absMax.
- * If the value is below the minimum, it will be clamped to zero.
- * If the value is above the maximum, it will be clamped to the maximum.
- *
- * @param value Value to clamp
- * @param absMin Absolute value of the minimum significant value to return
- * @param absMax Absolute value of the maximum value to return
- * @return The clamped value with the same sign as <code>value</code>
- */
- private int clampMag(int value, int absMin, int absMax) {
- final int absValue = Math.abs(value);
- if (absValue < absMin) return 0;
- if (absValue > absMax) return value > 0 ? absMax : -absMax;
- return value;
- }
-
- /**
- * Clamp the magnitude of value for absMin and absMax.
- * If the value is below the minimum, it will be clamped to zero.
- * If the value is above the maximum, it will be clamped to the maximum.
- *
- * @param value Value to clamp
- * @param absMin Absolute value of the minimum significant value to return
- * @param absMax Absolute value of the maximum value to return
- * @return The clamped value with the same sign as <code>value</code>
- */
- private float clampMag(float value, float absMin, float absMax) {
- final float absValue = Math.abs(value);
- if (absValue < absMin) return 0;
- if (absValue > absMax) return value > 0 ? absMax : -absMax;
- return value;
- }
-
- private float distanceInfluenceForSnapDuration(float f) {
- f -= 0.5f; // center the values about 0.
- f *= 0.3f * Math.PI / 2.0f;
- return (float) Math.sin(f);
- }
-
- /**
- * Settle the captured view based on standard free-moving fling behavior.
- * The caller should invoke {@link #continueSettling(boolean)} on each subsequent frame
- * to continue the motion until it returns false.
- *
- * @param minLeft Minimum X position for the view's left edge
- * @param minTop Minimum Y position for the view's top edge
- * @param maxLeft Maximum X position for the view's left edge
- * @param maxTop Maximum Y position for the view's top edge
- */
- public void flingCapturedView(int minLeft, int minTop, int maxLeft, int maxTop) {
- if (!mReleaseInProgress) {
- throw new IllegalStateException("Cannot flingCapturedView outside of a call to " +
- "Callback#onViewReleased");
- }
-
- final int yVelocity = (int) VelocityTrackerCompat
- .getYVelocity(mVelocityTracker, mActivePointerId);
- mScroller.fling(mCapturedView.getLeft(), mCapturedView.getTop(),
- (int) VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
- yVelocity, minLeft, maxLeft, minTop, maxTop);
- mFinalScrollY = yVelocity < 0 ? minTop : maxTop;
-
- setDragState(STATE_SETTLING);
- }
-
- /**
- * Settle the captured view based on standard free-moving fling behavior.
- * The caller should invoke {@link #continueSettling(boolean)} on each subsequent frame
- * to continue the motion until it returns false.
- *
- * @param minLeft Minimum X position for the view's left edge
- * @param minTop Minimum Y position for the view's top edge
- * @param maxLeft Maximum X position for the view's left edge
- * @param maxTop Maximum Y position for the view's top edge
- * @param yvel the Y velocity to fling with
- */
- public void flingCapturedView(int minLeft, int minTop, int maxLeft, int maxTop, int yvel) {
- if (!mReleaseInProgress) {
- throw new IllegalStateException("Cannot flingCapturedView outside of a call to " +
- "Callback#onViewReleased");
- }
- mScroller.abortAnimation();
- mScroller.fling(mCapturedView.getLeft(), mCapturedView.getTop(), 0, yvel,
- Integer.MIN_VALUE, Integer.MAX_VALUE, Integer.MIN_VALUE, Integer.MAX_VALUE);
- mFinalScrollY = yvel < 0 ? minTop : maxTop;
-
- setDragState(STATE_SETTLING);
- }
-
- /**
- * Predict how far a fling with {@param yvel} will cause the view to travel from stand still.
- * @return predicted y offset
- */
- public int predictFlingYOffset(int yvel) {
- mScroller.abortAnimation();
- mScroller.fling(0, 0, 0, yvel, Integer.MIN_VALUE, Integer.MAX_VALUE, Integer.MIN_VALUE,
- Integer.MAX_VALUE);
- final int finalY = mScroller.getFinalY();
- mScroller.abortAnimation();
- return finalY;
- }
-
- /**
- * Move the captured settling view by the appropriate amount for the current time.
- * If <code>continueSettling</code> returns true, the caller should call it again
- * on the next frame to continue.
- *
- * @param deferCallbacks true if state callbacks should be deferred via posted message.
- * Set this to true if you are calling this method from
- * {@link android.view.View#computeScroll()} or similar methods
- * invoked as part of layout or drawing.
- * @return true if settle is still in progress
- */
- public boolean continueSettling(boolean deferCallbacks) {
- if (mDragState == STATE_SETTLING) {
- boolean keepGoing = mScroller.computeScrollOffset();
- int y = mScroller.getCurrY();
-
- // Since Scroller's getFinalY() can't be properly set (b/17704016), we need to
- // perform clamping of mScroller.getCurrY() here.
- if (y - mCapturedView.getTop() > 0) {
- y = Math.min(y, mFinalScrollY);
- } else {
- y = Math.max(y, mFinalScrollY);
- }
- final int dy = y - mCapturedView.getTop();
-
- if (dy != 0) {
- mCapturedView.offsetTopAndBottom(dy);
- mCallback.onViewPositionChanged(mCapturedView, 0, y, 0, dy);
- }
-
- if (keepGoing && y == mFinalScrollY) {
- // Close enough. The interpolator/scroller might think we're still moving
- // but the user sure doesn't.
- mScroller.abortAnimation();
- keepGoing = mScroller.isFinished();
- }
-
- if (!keepGoing) {
- if (deferCallbacks) {
- mParentView.post(mSetIdleRunnable);
- } else {
- setDragState(STATE_IDLE);
- }
- }
- }
-
- return mDragState == STATE_SETTLING;
- }
-
- public void processNestedFling(View target, int yvel) {
- mCapturedView = target;
- dispatchViewFling(0, yvel);
- }
-
- public int getVelocityMagnitude() {
- // Use Math.abs() to ensure this always returns an absolute value, even if the
- // ScrollerCompat implementation changes.
- return (int) Math.abs(mScroller.getCurrVelocity());
- }
-
- private void dispatchViewFling(float xvel, float yvel) {
- mReleaseInProgress = true;
- mCallback.onViewFling(mCapturedView, xvel, yvel);
- mReleaseInProgress = false;
-
- if (mDragState == STATE_DRAGGING) {
- // onViewReleased didn't call a method that would have changed this. Go idle.
- setDragState(STATE_IDLE);
- }
- }
-
- /**
- * Like all callback events this must happen on the UI thread, but release
- * involves some extra semantics. During a release (mReleaseInProgress)
- * is the only time it is valid to call {@link #settleCapturedViewAt(int, int)}
- * or {@link #flingCapturedView(int, int, int, int)}.
- */
- private void dispatchViewReleased(float xvel, float yvel) {
- mReleaseInProgress = true;
- mCallback.onViewReleased(mCapturedView, xvel, yvel);
- mReleaseInProgress = false;
-
- if (mDragState == STATE_DRAGGING) {
- // onViewReleased didn't call a method that would have changed this. Go idle.
- setDragState(STATE_IDLE);
- }
- }
-
- private void clearMotionHistory() {
- if (mInitialMotionX == null) {
- return;
- }
- Arrays.fill(mInitialMotionX, 0);
- Arrays.fill(mInitialMotionY, 0);
- Arrays.fill(mLastMotionX, 0);
- Arrays.fill(mLastMotionY, 0);
- Arrays.fill(mInitialEdgesTouched, 0);
- Arrays.fill(mEdgeDragsInProgress, 0);
- Arrays.fill(mEdgeDragsLocked, 0);
- mPointersDown = 0;
- }
-
- private void clearMotionHistory(int pointerId) {
- if (mInitialMotionX == null) {
- return;
- }
- mInitialMotionX[pointerId] = 0;
- mInitialMotionY[pointerId] = 0;
- mLastMotionX[pointerId] = 0;
- mLastMotionY[pointerId] = 0;
- mInitialEdgesTouched[pointerId] = 0;
- mEdgeDragsInProgress[pointerId] = 0;
- mEdgeDragsLocked[pointerId] = 0;
- mPointersDown &= ~(1 << pointerId);
- }
-
- private void ensureMotionHistorySizeForId(int pointerId) {
- if (mInitialMotionX == null || mInitialMotionX.length <= pointerId) {
- float[] imx = new float[pointerId + 1];
- float[] imy = new float[pointerId + 1];
- float[] lmx = new float[pointerId + 1];
- float[] lmy = new float[pointerId + 1];
- int[] iit = new int[pointerId + 1];
- int[] edip = new int[pointerId + 1];
- int[] edl = new int[pointerId + 1];
-
- if (mInitialMotionX != null) {
- System.arraycopy(mInitialMotionX, 0, imx, 0, mInitialMotionX.length);
- System.arraycopy(mInitialMotionY, 0, imy, 0, mInitialMotionY.length);
- System.arraycopy(mLastMotionX, 0, lmx, 0, mLastMotionX.length);
- System.arraycopy(mLastMotionY, 0, lmy, 0, mLastMotionY.length);
- System.arraycopy(mInitialEdgesTouched, 0, iit, 0, mInitialEdgesTouched.length);
- System.arraycopy(mEdgeDragsInProgress, 0, edip, 0, mEdgeDragsInProgress.length);
- System.arraycopy(mEdgeDragsLocked, 0, edl, 0, mEdgeDragsLocked.length);
- }
-
- mInitialMotionX = imx;
- mInitialMotionY = imy;
- mLastMotionX = lmx;
- mLastMotionY = lmy;
- mInitialEdgesTouched = iit;
- mEdgeDragsInProgress = edip;
- mEdgeDragsLocked = edl;
- }
- }
-
- private void saveInitialMotion(float x, float y, int pointerId) {
- ensureMotionHistorySizeForId(pointerId);
- mInitialMotionX[pointerId] = mLastMotionX[pointerId] = x;
- mInitialMotionY[pointerId] = mLastMotionY[pointerId] = y;
- mInitialEdgesTouched[pointerId] = getEdgesTouched((int) x, (int) y);
- mPointersDown |= 1 << pointerId;
- }
-
- private void saveLastMotion(MotionEvent ev) {
- final int pointerCount = MotionEventCompat.getPointerCount(ev);
- for (int i = 0; i < pointerCount; i++) {
- final int pointerId = MotionEventCompat.getPointerId(ev, i);
- final float x = MotionEventCompat.getX(ev, i);
- final float y = MotionEventCompat.getY(ev, i);
- mLastMotionX[pointerId] = x;
- mLastMotionY[pointerId] = y;
- }
- }
-
- /**
- * Check if the given pointer ID represents a pointer that is currently down (to the best
- * of the ViewDragHelper's knowledge).
- *
- * <p>The state used to report this information is populated by the methods
- * {@link #shouldInterceptTouchEvent(android.view.MotionEvent)} or
- * {@link #processTouchEvent(android.view.MotionEvent)}. If one of these methods has not
- * been called for all relevant MotionEvents to track, the information reported
- * by this method may be stale or incorrect.</p>
- *
- * @param pointerId pointer ID to check; corresponds to IDs provided by MotionEvent
- * @return true if the pointer with the given ID is still down
- */
- public boolean isPointerDown(int pointerId) {
- return (mPointersDown & 1 << pointerId) != 0;
- }
-
- void setDragState(int state) {
- if (mDragState != state) {
- mDragState = state;
- mCallback.onViewDragStateChanged(state);
- if (state == STATE_IDLE) {
- mCapturedView = null;
- }
- }
- }
-
- /**
- * Attempt to capture the view with the given pointer ID. The callback will be involved.
- * This will put us into the "dragging" state. If we've already captured this view with
- * this pointer this method will immediately return true without consulting the callback.
- *
- * @param toCapture View to capture
- * @param pointerId Pointer to capture with
- * @return true if capture was successful
- */
- boolean tryCaptureViewForDrag(View toCapture, int pointerId) {
- if (toCapture == mCapturedView && mActivePointerId == pointerId) {
- // Already done!
- return true;
- }
- if (toCapture != null && mCallback.tryCaptureView(toCapture, pointerId)) {
- mActivePointerId = pointerId;
- captureChildView(toCapture, pointerId);
- return true;
- }
- return false;
- }
-
- /**
- * Tests scrollability within child views of v given a delta of dx.
- *
- * @param v View to test for horizontal scrollability
- * @param checkV Whether the view v passed should itself be checked for scrollability (true),
- * or just its children (false).
- * @param dx Delta scrolled in pixels along the X axis
- * @param dy Delta scrolled in pixels along the Y axis
- * @param x X coordinate of the active touch point
- * @param y Y coordinate of the active touch point
- * @return true if child views of v can be scrolled by delta of dx.
- */
- protected boolean canScroll(View v, boolean checkV, int dx, int dy, int x, int y) {
- if (v instanceof ViewGroup) {
- final ViewGroup group = (ViewGroup) v;
- final int scrollX = v.getScrollX();
- final int scrollY = v.getScrollY();
- final int count = group.getChildCount();
- // Count backwards - let topmost views consume scroll distance first.
- for (int i = count - 1; i >= 0; i--) {
- // TODO: Add versioned support here for transformed views.
- // This will not work for transformed views in Honeycomb+
- final View child = group.getChildAt(i);
- if (x + scrollX >= child.getLeft() && x + scrollX < child.getRight() &&
- y + scrollY >= child.getTop() && y + scrollY < child.getBottom() &&
- canScroll(child, true, dx, dy, x + scrollX - child.getLeft(),
- y + scrollY - child.getTop())) {
- return true;
- }
- }
- }
-
- return checkV && (ViewCompat.canScrollHorizontally(v, -dx) ||
- ViewCompat.canScrollVertically(v, -dy));
- }
-
- /**
- * Check if this event as provided to the parent view's onInterceptTouchEvent should
- * cause the parent to intercept the touch event stream.
- *
- * @param ev MotionEvent provided to onInterceptTouchEvent
- * @return true if the parent view should return true from onInterceptTouchEvent
- */
- public boolean shouldInterceptTouchEvent(MotionEvent ev) {
- final int action = MotionEventCompat.getActionMasked(ev);
- final int actionIndex = MotionEventCompat.getActionIndex(ev);
-
- if (action == MotionEvent.ACTION_DOWN) {
- // Reset things for a new event stream, just in case we didn't get
- // the whole previous stream.
- cancel();
- }
-
- if (mVelocityTracker == null) {
- mVelocityTracker = VelocityTracker.obtain();
- }
- mVelocityTracker.addMovement(ev);
-
- switch (action) {
- case MotionEvent.ACTION_DOWN: {
- final float x = ev.getX();
- final float y = ev.getY();
- final int pointerId = MotionEventCompat.getPointerId(ev, 0);
- saveInitialMotion(x, y, pointerId);
-
- final View toCapture = findTopChildUnder((int) x, (int) y);
-
- // Catch a settling view if possible.
- if (toCapture == mCapturedView && mDragState == STATE_SETTLING) {
- tryCaptureViewForDrag(toCapture, pointerId);
- }
-
- final int edgesTouched = mInitialEdgesTouched[pointerId];
- if ((edgesTouched & mTrackingEdges) != 0) {
- mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
- }
- break;
- }
-
- case MotionEventCompat.ACTION_POINTER_DOWN: {
- final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
- final float x = MotionEventCompat.getX(ev, actionIndex);
- final float y = MotionEventCompat.getY(ev, actionIndex);
-
- saveInitialMotion(x, y, pointerId);
-
- // A ViewDragHelper can only manipulate one view at a time.
- if (mDragState == STATE_IDLE) {
- final int edgesTouched = mInitialEdgesTouched[pointerId];
- if ((edgesTouched & mTrackingEdges) != 0) {
- mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
- }
- } else if (mDragState == STATE_SETTLING) {
- // Catch a settling view if possible.
- final View toCapture = findTopChildUnder((int) x, (int) y);
- if (toCapture == mCapturedView) {
- tryCaptureViewForDrag(toCapture, pointerId);
- }
- }
- break;
- }
-
- case MotionEvent.ACTION_MOVE: {
- // First to cross a touch slop over a draggable view wins. Also report edge drags.
- final int pointerCount = MotionEventCompat.getPointerCount(ev);
- for (int i = 0; i < pointerCount; i++) {
- final int pointerId = MotionEventCompat.getPointerId(ev, i);
- final float x = MotionEventCompat.getX(ev, i);
- final float y = MotionEventCompat.getY(ev, i);
- final float dx = x - mInitialMotionX[pointerId];
- final float dy = y - mInitialMotionY[pointerId];
-
- reportNewEdgeDrags(dx, dy, pointerId);
- if (mDragState == STATE_DRAGGING) {
- // Callback might have started an edge drag
- break;
- }
-
- final View toCapture = findTopChildUnder((int) x, (int) y);
- if (toCapture != null && checkTouchSlop(toCapture, dx, dy) &&
- tryCaptureViewForDrag(toCapture, pointerId)) {
- break;
- }
- }
- saveLastMotion(ev);
- break;
- }
-
- case MotionEventCompat.ACTION_POINTER_UP: {
- final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
- clearMotionHistory(pointerId);
- break;
- }
-
- case MotionEvent.ACTION_UP:
- case MotionEvent.ACTION_CANCEL: {
- cancel();
- break;
- }
- }
-
- return mDragState == STATE_DRAGGING;
- }
-
- /**
- * Process a touch event received by the parent view. This method will dispatch callback events
- * as needed before returning. The parent view's onTouchEvent implementation should call this.
- *
- * @param ev The touch event received by the parent view
- */
- public void processTouchEvent(MotionEvent ev) {
- final int action = MotionEventCompat.getActionMasked(ev);
- final int actionIndex = MotionEventCompat.getActionIndex(ev);
-
- if (action == MotionEvent.ACTION_DOWN) {
- // Reset things for a new event stream, just in case we didn't get
- // the whole previous stream.
- cancel();
- }
-
- if (mVelocityTracker == null) {
- mVelocityTracker = VelocityTracker.obtain();
- }
- mVelocityTracker.addMovement(ev);
-
- switch (action) {
- case MotionEvent.ACTION_DOWN: {
- final float x = ev.getX();
- final float y = ev.getY();
- final int pointerId = MotionEventCompat.getPointerId(ev, 0);
- final View toCapture = findTopChildUnder((int) x, (int) y);
-
- saveInitialMotion(x, y, pointerId);
-
- // Since the parent is already directly processing this touch event,
- // there is no reason to delay for a slop before dragging.
- // Start immediately if possible.
- tryCaptureViewForDrag(toCapture, pointerId);
-
- final int edgesTouched = mInitialEdgesTouched[pointerId];
- if ((edgesTouched & mTrackingEdges) != 0) {
- mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
- }
- break;
- }
-
- case MotionEventCompat.ACTION_POINTER_DOWN: {
- final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
- final float x = MotionEventCompat.getX(ev, actionIndex);
- final float y = MotionEventCompat.getY(ev, actionIndex);
-
- saveInitialMotion(x, y, pointerId);
-
- // A ViewDragHelper can only manipulate one view at a time.
- if (mDragState == STATE_IDLE) {
- // If we're idle we can do anything! Treat it like a normal down event.
-
- final View toCapture = findTopChildUnder((int) x, (int) y);
- tryCaptureViewForDrag(toCapture, pointerId);
-
- final int edgesTouched = mInitialEdgesTouched[pointerId];
- if ((edgesTouched & mTrackingEdges) != 0) {
- mCallback.onEdgeTouched(edgesTouched & mTrackingEdges, pointerId);
- }
- } else if (isCapturedViewUnder((int) x, (int) y)) {
- // We're still tracking a captured view. If the same view is under this
- // point, we'll swap to controlling it with this pointer instead.
- // (This will still work if we're "catching" a settling view.)
-
- tryCaptureViewForDrag(mCapturedView, pointerId);
- }
- break;
- }
-
- case MotionEvent.ACTION_MOVE: {
- if (mDragState == STATE_DRAGGING) {
- int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
- if (index < 0) {
- Log.e(TAG, "Pointer index for id " + mActivePointerId + " not found."
- + " Skipping MotionEvent");
- return;
- }
- final float x = MotionEventCompat.getX(ev, index);
- final float y = MotionEventCompat.getY(ev, index);
- final int idx = (int) (x - mLastMotionX[mActivePointerId]);
- final int idy = (int) (y - mLastMotionY[mActivePointerId]);
-
- dragTo(mCapturedView.getLeft() + idx, mCapturedView.getTop() + idy, idx, idy);
-
- saveLastMotion(ev);
- } else {
- // Check to see if any pointer is now over a draggable view.
- final int pointerCount = MotionEventCompat.getPointerCount(ev);
- for (int i = 0; i < pointerCount; i++) {
- final int pointerId = MotionEventCompat.getPointerId(ev, i);
- final float x = MotionEventCompat.getX(ev, i);
- final float y = MotionEventCompat.getY(ev, i);
- final float dx = x - mInitialMotionX[pointerId];
- final float dy = y - mInitialMotionY[pointerId];
-
- reportNewEdgeDrags(dx, dy, pointerId);
- if (mDragState == STATE_DRAGGING) {
- // Callback might have started an edge drag.
- break;
- }
-
- final View toCapture = findTopChildUnder((int) x, (int) y);
- if (checkTouchSlop(toCapture, dx, dy) &&
- tryCaptureViewForDrag(toCapture, pointerId)) {
- break;
- }
- }
- saveLastMotion(ev);
- }
- break;
- }
-
- case MotionEventCompat.ACTION_POINTER_UP: {
- final int pointerId = MotionEventCompat.getPointerId(ev, actionIndex);
- if (mDragState == STATE_DRAGGING && pointerId == mActivePointerId) {
- // Try to find another pointer that's still holding on to the captured view.
- int newActivePointer = INVALID_POINTER;
- final int pointerCount = MotionEventCompat.getPointerCount(ev);
- for (int i = 0; i < pointerCount; i++) {
- final int id = MotionEventCompat.getPointerId(ev, i);
- if (id == mActivePointerId) {
- // This one's going away, skip.
- continue;
- }
-
- final float x = MotionEventCompat.getX(ev, i);
- final float y = MotionEventCompat.getY(ev, i);
- if (findTopChildUnder((int) x, (int) y) == mCapturedView &&
- tryCaptureViewForDrag(mCapturedView, id)) {
- newActivePointer = mActivePointerId;
- break;
- }
- }
-
- if (newActivePointer == INVALID_POINTER) {
- // We didn't find another pointer still touching the view, release it.
- releaseViewForPointerUp();
- }
- }
- clearMotionHistory(pointerId);
- break;
- }
-
- case MotionEvent.ACTION_UP: {
- if (mDragState == STATE_DRAGGING) {
- releaseViewForPointerUp();
- }
- cancel();
- break;
- }
-
- case MotionEvent.ACTION_CANCEL: {
- if (mDragState == STATE_DRAGGING) {
- dispatchViewReleased(0, 0);
- }
- cancel();
- break;
- }
- }
- }
-
- private void reportNewEdgeDrags(float dx, float dy, int pointerId) {
- int dragsStarted = 0;
- if (checkNewEdgeDrag(dx, dy, pointerId, EDGE_LEFT)) {
- dragsStarted |= EDGE_LEFT;
- }
- if (checkNewEdgeDrag(dy, dx, pointerId, EDGE_TOP)) {
- dragsStarted |= EDGE_TOP;
- }
- if (checkNewEdgeDrag(dx, dy, pointerId, EDGE_RIGHT)) {
- dragsStarted |= EDGE_RIGHT;
- }
- if (checkNewEdgeDrag(dy, dx, pointerId, EDGE_BOTTOM)) {
- dragsStarted |= EDGE_BOTTOM;
- }
-
- if (dragsStarted != 0) {
- mEdgeDragsInProgress[pointerId] |= dragsStarted;
- mCallback.onEdgeDragStarted(dragsStarted, pointerId);
- }
- }
-
- private boolean checkNewEdgeDrag(float delta, float odelta, int pointerId, int edge) {
- final float absDelta = Math.abs(delta);
- final float absODelta = Math.abs(odelta);
-
- if ((mInitialEdgesTouched[pointerId] & edge) != edge || (mTrackingEdges & edge) == 0 ||
- (mEdgeDragsLocked[pointerId] & edge) == edge ||
- (mEdgeDragsInProgress[pointerId] & edge) == edge ||
- (absDelta <= mTouchSlop && absODelta <= mTouchSlop)) {
- return false;
- }
- if (absDelta < absODelta * 0.5f && mCallback.onEdgeLock(edge)) {
- mEdgeDragsLocked[pointerId] |= edge;
- return false;
- }
- return (mEdgeDragsInProgress[pointerId] & edge) == 0 && absDelta > mTouchSlop;
- }
-
- /**
- * Check if we've crossed a reasonable touch slop for the given child view.
- * If the child cannot be dragged along the horizontal or vertical axis, motion
- * along that axis will not count toward the slop check.
- *
- * @param child Child to check
- * @param dx Motion since initial position along X axis
- * @param dy Motion since initial position along Y axis
- * @return true if the touch slop has been crossed
- */
- private boolean checkTouchSlop(View child, float dx, float dy) {
- if (child == null) {
- return false;
- }
- final boolean checkHorizontal = mCallback.getViewHorizontalDragRange(child) > 0;
- final boolean checkVertical = mCallback.getViewVerticalDragRange(child) > 0;
-
- if (checkHorizontal && checkVertical) {
- return dx * dx + dy * dy > mTouchSlop * mTouchSlop;
- } else if (checkHorizontal) {
- return Math.abs(dx) > mTouchSlop;
- } else if (checkVertical) {
- return Math.abs(dy) > mTouchSlop;
- }
- return false;
- }
-
- /**
- * Check if any pointer tracked in the current gesture has crossed
- * the required slop threshold.
- *
- * <p>This depends on internal state populated by
- * {@link #shouldInterceptTouchEvent(android.view.MotionEvent)} or
- * {@link #processTouchEvent(android.view.MotionEvent)}. You should only rely on
- * the results of this method after all currently available touch data
- * has been provided to one of these two methods.</p>
- *
- * @param directions Combination of direction flags, see {@link #DIRECTION_HORIZONTAL},
- * {@link #DIRECTION_VERTICAL}, {@link #DIRECTION_ALL}
- * @return true if the slop threshold has been crossed, false otherwise
- */
- public boolean checkTouchSlop(int directions) {
- final int count = mInitialMotionX.length;
- for (int i = 0; i < count; i++) {
- if (checkTouchSlop(directions, i)) {
- return true;
- }
- }
- return false;
- }
-
- /**
- * Check if the specified pointer tracked in the current gesture has crossed
- * the required slop threshold.
- *
- * <p>This depends on internal state populated by
- * {@link #shouldInterceptTouchEvent(android.view.MotionEvent)} or
- * {@link #processTouchEvent(android.view.MotionEvent)}. You should only rely on
- * the results of this method after all currently available touch data
- * has been provided to one of these two methods.</p>
- *
- * @param directions Combination of direction flags, see {@link #DIRECTION_HORIZONTAL},
- * {@link #DIRECTION_VERTICAL}, {@link #DIRECTION_ALL}
- * @param pointerId ID of the pointer to slop check as specified by MotionEvent
- * @return true if the slop threshold has been crossed, false otherwise
- */
- public boolean checkTouchSlop(int directions, int pointerId) {
- if (!isPointerDown(pointerId)) {
- return false;
- }
-
- final boolean checkHorizontal = (directions & DIRECTION_HORIZONTAL) == DIRECTION_HORIZONTAL;
- final boolean checkVertical = (directions & DIRECTION_VERTICAL) == DIRECTION_VERTICAL;
-
- final float dx = mLastMotionX[pointerId] - mInitialMotionX[pointerId];
- final float dy = mLastMotionY[pointerId] - mInitialMotionY[pointerId];
-
- if (checkHorizontal && checkVertical) {
- return dx * dx + dy * dy > mTouchSlop * mTouchSlop;
- } else if (checkHorizontal) {
- return Math.abs(dx) > mTouchSlop;
- } else if (checkVertical) {
- return Math.abs(dy) > mTouchSlop;
- }
- return false;
- }
-
- /**
- * Check if any of the edges specified were initially touched in the currently active gesture.
- * If there is no currently active gesture this method will return false.
- *
- * @param edges Edges to check for an initial edge touch. See {@link #EDGE_LEFT},
- * {@link #EDGE_TOP}, {@link #EDGE_RIGHT}, {@link #EDGE_BOTTOM} and
- * {@link #EDGE_ALL}
- * @return true if any of the edges specified were initially touched in the current gesture
- */
- public boolean isEdgeTouched(int edges) {
- final int count = mInitialEdgesTouched.length;
- for (int i = 0; i < count; i++) {
- if (isEdgeTouched(edges, i)) {
- return true;
- }
- }
- return false;
- }
-
- /**
- * Check if any of the edges specified were initially touched by the pointer with
- * the specified ID. If there is no currently active gesture or if there is no pointer with
- * the given ID currently down this method will return false.
- *
- * @param edges Edges to check for an initial edge touch. See {@link #EDGE_LEFT},
- * {@link #EDGE_TOP}, {@link #EDGE_RIGHT}, {@link #EDGE_BOTTOM} and
- * {@link #EDGE_ALL}
- * @return true if any of the edges specified were initially touched in the current gesture
- */
- public boolean isEdgeTouched(int edges, int pointerId) {
- return isPointerDown(pointerId) && (mInitialEdgesTouched[pointerId] & edges) != 0;
- }
-
- private void releaseViewForPointerUp() {
- mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity);
- final float xvel = clampMag(
- VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),
- mMinVelocity, mMaxVelocity);
- final float yvel = clampMag(
- VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId),
- mMinVelocity, mMaxVelocity);
- dispatchViewReleased(xvel, yvel);
- }
-
- private void dragTo(int left, int top, int dx, int dy) {
- int clampedX = left;
- int clampedY = top;
- final int oldLeft = mCapturedView.getLeft();
- final int oldTop = mCapturedView.getTop();
- if (dx != 0) {
- clampedX = mCallback.clampViewPositionHorizontal(mCapturedView, left, dx);
- mCapturedView.offsetLeftAndRight(clampedX - oldLeft);
- }
- if (dy != 0) {
- clampedY = mCallback.clampViewPositionVertical(mCapturedView, top, dy);
- mCapturedView.offsetTopAndBottom(clampedY - oldTop);
- }
-
- if (dx != 0 || dy != 0) {
- final int clampedDx = clampedX - oldLeft;
- final int clampedDy = clampedY - oldTop;
- mCallback.onViewPositionChanged(mCapturedView, clampedX, clampedY,
- clampedDx, clampedDy);
- }
- }
-
- /**
- * Determine if the currently captured view is under the given point in the
- * parent view's coordinate system. If there is no captured view this method
- * will return false.
- *
- * @param x X position to test in the parent's coordinate system
- * @param y Y position to test in the parent's coordinate system
- * @return true if the captured view is under the given point, false otherwise
- */
- public boolean isCapturedViewUnder(int x, int y) {
- return isViewUnder(mCapturedView, x, y);
- }
-
- /**
- * Determine if the supplied view is under the given point in the
- * parent view's coordinate system.
- *
- * @param view Child view of the parent to hit test
- * @param x X position to test in the parent's coordinate system
- * @param y Y position to test in the parent's coordinate system
- * @return true if the supplied view is under the given point, false otherwise
- */
- public boolean isViewUnder(View view, int x, int y) {
- if (view == null) {
- return false;
- }
- return x >= view.getLeft() &&
- x < view.getRight() &&
- y >= view.getTop() &&
- y < view.getBottom();
- }
-
- /**
- * Find the topmost child under the given point within the parent view's coordinate system.
- * The child order is determined using {@link Callback#getOrderedChildIndex(int)}.
- *
- * @param x X position to test in the parent's coordinate system
- * @param y Y position to test in the parent's coordinate system
- * @return The topmost child view under (x, y) or null if none found.
- */
- public View findTopChildUnder(int x, int y) {
- final int childCount = mParentView.getChildCount();
- for (int i = childCount - 1; i >= 0; i--) {
- final View child = mParentView.getChildAt(mCallback.getOrderedChildIndex(i));
- if (x >= child.getLeft() && x < child.getRight() &&
- y >= child.getTop() && y < child.getBottom()) {
- return child;
- }
- }
- return null;
- }
-
- private int getEdgesTouched(int x, int y) {
- int result = 0;
-
- if (x < mParentView.getLeft() + mEdgeSize) result |= EDGE_LEFT;
- if (y < mParentView.getTop() + mEdgeSize) result |= EDGE_TOP;
- if (x > mParentView.getRight() - mEdgeSize) result |= EDGE_RIGHT;
- if (y > mParentView.getBottom() - mEdgeSize) result |= EDGE_BOTTOM;
-
- return result;
- }
-
- /**
- * Prepares the {@link ViewDragHelper} for the beginning of a nested scroll.
- *
- * @param target The child view that is dispatching the nested scroll.
- */
- public void startNestedScroll(View target) {
- if (mVelocityTracker == null) {
- mVelocityTracker = VelocityTracker.obtain();
- }
- setDragState(STATE_DRAGGING);
- mCapturedView = target;
- }
-
- /**
- * Informs the {@link ViewDragHelper} that a nested scroll has ended.
- *
- * @param target The child view that is dispatching the nested scroll.
- */
- public void stopNestedScroll(View target) {
- mCapturedView = target;
- dispatchViewReleased(0, 0);
- }
-
- /**
- * Update the {@link ViewDragHelper} with a new nested scrolling event.
- *
- * @param target The child view that is dispatching the nested scroll.
- * @param dx The x distance scrolled on the child, in pixels.
- * @param dy The y distance scroll on the child, in pixels.
- * @param consumed An int array for the {@link ViewDragHelper} to report back the scroll
- * deltas that it consumed.
- */
- public void processNestedScroll(View target, int dx, int dy, int[] consumed) {
- if (mCapturedView == null) {
- // This is safe because consumed array is null when called from
- // onNestedScroll, and pre-initialized to {0, 0} when called from
- // onNestedPreScroll.
- return;
- }
- final int targetX = mCapturedView.getLeft() + dx;
- final int targetY = mCapturedView.getTop() + dy;
- dragTo(targetX, targetY, dx, dy);
- if (consumed != null) {
- final int unconsumedX = targetX - mCapturedView.getLeft();
- final int unconsumedY = targetY - mCapturedView.getTop();
- consumed[0] = unconsumedX - dx;
- consumed[1] = unconsumedY - dy;
- }
- }
-
-}