Android 侧滑效果的简单实现。

先看效果：

首先，导入包：

compile files('libs/nineoldandroids-2.4.0.jar')

r然后在main中创建一个widget包。
c创建ViewDragHelper类

public class ViewDragHelper {private static final String TAG = "ViewDragHelper";public static final int INVALID_POINTER = -1public static final int STATE_IDLE = 0;public static final int STATE_DRAGGING = 1;public static final int STATE_SETTLING = 2;public static final int EDGE_LEFT = 1 << 0;public static final int EDGE_RIGHT = 1 << 1public static final int EDGE_TOP = 1 << 2;public static final int EDGE_BOTTOM = 1 << 3public static final int EDGE_ALL = EDGE_LEFT | EDGE_TOP | EDGE_RIGHT | EDGE_BOTTOM;public static final int DIRECTION_HORIZONTAL = 1 << 0;public static final int DIRECTION_VERTICAL = 1 << 1;public static final int DIRECTION_ALL = DIRECTION_HORIZONTAL | DIRECTION_VERTICAL;private static final int EDGE_SIZE = 20; // dpprivate static final int BASE_SETTLE_DURATION = 256; // msprivate static final int MAX_SETTLE_DURATION = 600; // ms// Current drag state; idle, dragging or settlingprivate int mDragState;// Distance to travel before a drag may beginprivate int mTouchSlop;// Last known position/pointer trackingprivate 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 final float mMaxVelocity;private float mMinVelocity;private final int mEdgeSize;private int mTrackingEdges;private final ScrollerCompat mScroller;private final Callback mCallback;private View mCapturedView;private boolean mReleaseInProgress;private final ViewGroup mParentView;private static final Interpolator sInterpolator = new Interpolator() {public float getInterpolation(float t) {t -= 1.0f;return t * t * t * t * t + 1.0f;}};private final Runnable mSetIdleRunnable = new Runnable() {public void run() {setDragState(STATE_IDLE);}};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 = ScrollerCompat.create(context, sInterpolator);}public static abstract class Callback {public void onViewDragStateChanged(int state) {}public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {}public void onViewCaptured(View capturedChild, int activePointerId) {}public void onViewReleased(View releasedChild, float xvel, float yvel) {}public void onEdgeTouched(int edgeFlags, int pointerId) {}public boolean onEdgeLock(int edgeFlags) {return false;}public void onEdgeDragStarted(int edgeFlags, int pointerId) {}public int getOrderedChildIndex(int index) {return index;}public int getViewHorizontalDragRange(View child) {return 0;}public int getViewVerticalDragRange(View child) {return 0;}public abstract boolean tryCaptureView(View child, int pointerId);public int clampViewPositionHorizontal(View child, int left, int dx) {return 0;}public int clampViewPositionVertical(View child, int top, int dy) {return 0;}}public static ViewDragHelper create(ViewGroup forParent, Callback cb) {return new ViewDragHelper(forParent.getContext(), forParent, cb);}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;}public void setMinVelocity(float minVel) {mMinVelocity = minVel;}public float getMinVelocity() {return mMinVelocity;}public int getViewDragState() {return mDragState;}public void setEdgeTrackingEnabled(int edgeFlags) {mTrackingEdges = edgeFlags;}public int getEdgeSize() {return mEdgeSize;}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);}public View getCapturedView() {return mCapturedView;}public int getActivePointerId() {return mActivePointerId;}public int getTouchSlop() {return mTouchSlop;}public void cancel() {mActivePointerId = INVALID_POINTER;clearMotionHistory();if (mVelocityTracker != null) {mVelocityTracker.recycle();mVelocityTracker = null;}}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);}public boolean smoothSlideViewTo(View child, int finalLeft, int finalTop) {mCapturedView = child;mActivePointerId = INVALID_POINTER;boolean continueSliding = forceSettleCapturedViewAt(finalLeft, finalTop, 0, 0);if (!continueSliding && mDragState == STATE_IDLE && mCapturedView != null) {// If we're in an IDLE state to begin with and aren't moving anywhere, we// end up having a non-null capturedView with an IDLE dragStatemCapturedView = null;}return continueSliding;}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));}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);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);}private static 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;}private static 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 static float distanceInfluenceForSnapDuration(float f) {f -= 0.5f; // center the values about 0.f *= 0.3f * Math.PI / 2.0f;return (float) Math.sin(f);}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");}mScroller.fling(mCapturedView.getLeft(), mCapturedView.getTop(),(int) VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId),(int) VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId),minLeft, maxLeft, minTop, maxTop);setDragState(STATE_SETTLING);}public boolean continueSettling(boolean deferCallbacks) {if (mDragState == STATE_SETTLING) {boolean keepGoing = mScroller.computeScrollOffset();final int x = mScroller.getCurrX();final int y = mScroller.getCurrY();final int dx = x - mCapturedView.getLeft();final int dy = y - mCapturedView.getTop();if (dx != 0) {mCapturedView.offsetLeftAndRight(dx);}if (dy != 0) {mCapturedView.offsetTopAndBottom(dy);}if (dx != 0 || dy != 0) {mCallback.onViewPositionChanged(mCapturedView, x, y, dx, dy);}if (keepGoing && x == mScroller.getFinalX() && y == mScroller.getFinalY()) {// Close enough. The interpolator/scroller might think we're still moving// but the user sure doesn't.mScroller.abortAnimation();keepGoing = false;}if (!keepGoing) {if (deferCallbacks) {mParentView.post(mSetIdleRunnable);} else {setDragState(STATE_IDLE);}}}return mDragState == STATE_SETTLING;}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;}}public boolean isPointerDown(int pointerId) {return (mPointersDown & 1 << pointerId) != 0;}void setDragState(int state) {mParentView.removeCallbacks(mSetIdleRunnable);if (mDragState != state) {mDragState = state;mCallback.onViewDragStateChanged(state);if (mDragState == STATE_IDLE) {mCapturedView = null;}}}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;}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));}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: {if (mInitialMotionX == null || mInitialMotionY == null) break;// 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];final View toCapture = findTopChildUnder((int) x, (int) y);final boolean pastSlop = toCapture != null && checkTouchSlop(toCapture, dx, dy);if (pastSlop) {// check the callback's// getView[Horizontal|Vertical]DragRange methods to know// if you can move at all along an axis, then see if it// would clamp to the same value. If you can't move at// all in every dimension with a nonzero range, bail.final int oldLeft = toCapture.getLeft();final int targetLeft = oldLeft + (int) dx;final int newLeft = mCallback.clampViewPositionHorizontal(toCapture,targetLeft, (int) dx);final int oldTop = toCapture.getTop();final int targetTop = oldTop + (int) dy;final int newTop = mCallback.clampViewPositionVertical(toCapture, targetTop,(int) dy);final int horizontalDragRange = mCallback.getViewHorizontalDragRange(toCapture);final int verticalDragRange = mCallback.getViewVerticalDragRange(toCapture);if ((horizontalDragRange == 0 || horizontalDragRange > 0&& newLeft == oldLeft) && (verticalDragRange == 0|| verticalDragRange > 0 && newTop == oldTop)) {break;}}reportNewEdgeDrags(dx, dy, pointerId);if (mDragState == STATE_DRAGGING) {// Callback might have started an edge dragbreak;}if (pastSlop && 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;}default:break;}return mDragState == STATE_DRAGGING;}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) {final int index = MotionEventCompat.findPointerIndex(ev, mActivePointerId);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;}default: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;}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;}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;}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;}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;}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);}}public boolean isCapturedViewUnder(int x, int y) {return isViewUnder(mCapturedView, x, y);}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();}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;}
}

DragLayout布局继承FrameLayout：

public class DragLayout extends FrameLayout {private static final boolean IS_SHOW_SHADOW = true;//手势处理类private GestureDetectorCompat gestureDetector;//视图拖拽移动帮助类private ViewDragHelper dragHelper;//滑动监听器private DragListener dragListener;//水平拖拽的距离private int range;//宽度private int width;//高度private int height;//main视图距离在ViewGroup距离左边的距离private int mainLeft;private Context context;private ImageView ivShadow;//左侧布局private RelativeLayout vgLeft;//右侧(主界面布局)private CustomRelativeLayout vgMain;//页面状态 默认为关闭private Status status = Status.CLOSE;private final ViewDragHelper.Callback dragHelperCallback = new ViewDragHelper.Callback() {@Overridepublic int clampViewPositionHorizontal(View child, int left, int dx) {if (mainLeft + dx < 0) {return 0;} else if (mainLeft + dx > range) {return range;} else {return left;}}@Overridepublic boolean tryCaptureView(View child, int pointerId) {return true;}@Overridepublic int getViewHorizontalDragRange(View child) {return width;}@Overridepublic void onViewReleased(View releasedChild, float xvel, float yvel) {super.onViewReleased(releasedChild, xvel, yvel);if (xvel > 0) {open();} else if (xvel < 0) {close();} else if (releasedChild == vgMain && mainLeft > range * 0.3) {open();} else if (releasedChild == vgLeft && mainLeft > range * 0.7) {open();} else {close();}}@Overridepublic void onViewPositionChanged(View changedView, int left, int top,int dx, int dy) {if (changedView == vgMain) {mainLeft = left;} else {mainLeft = mainLeft + left;}if (mainLeft < 0) {mainLeft = 0;} else if (mainLeft > range) {mainLeft = range;}if (IS_SHOW_SHADOW) {ivShadow.layout(mainLeft, 0, mainLeft + width, height);}if (changedView == vgLeft) {vgLeft.layout(0, 0, width, height);vgMain.layout(mainLeft, 0, mainLeft + width, height);}dispatchDragEvent(mainLeft);}};public DragLayout(Context context) {this(context, null);}public DragLayout(Context context, AttributeSet attrs) {this(context, attrs, 0);this.context = context;}public DragLayout(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);gestureDetector = new GestureDetectorCompat(context, new YScrollDetector());dragHelper = ViewDragHelper.create(this, dragHelperCallback);}class YScrollDetector extends GestureDetector.SimpleOnGestureListener {@Overridepublic boolean onScroll(MotionEvent e1, MotionEvent e2, float dx, float dy) {return Math.abs(dy) <= Math.abs(dx);}}/*** 滑动相关回调接口*/public interface DragListener {//界面打开public void onOpen();//界面关闭public void onClose();//界面滑动过程中public void onDrag(float percent);}public void setDragListener(DragListener dragListener) {this.dragListener = dragListener;}/*** 布局加载完成回调* 做一些初始化的操作*/@Overrideprotected void onFinishInflate() {super.onFinishInflate();if (IS_SHOW_SHADOW) {ivShadow = new ImageView(context);ivShadow.setImageResource(R.mipmap.shadow);LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);addView(ivShadow, 1, lp);}//左侧界面vgLeft = (RelativeLayout) getChildAt(0);//右侧(主)界面vgMain = (CustomRelativeLayout) getChildAt(IS_SHOW_SHADOW ? 2 : 1);vgMain.setDragLayout(this);vgLeft.setClickable(true);vgMain.setClickable(true);}public ViewGroup getVgMain() {return vgMain;}public ViewGroup getVgLeft() {return vgLeft;}@Overrideprotected void onSizeChanged(int w, int h, int oldw, int oldh) {super.onSizeChanged(w, h, oldw, oldh);width = vgLeft.getMeasuredWidth();height = vgLeft.getMeasuredHeight();//可以水平拖拽滑动的距离 一共为屏幕宽度的80%range = (int) (width * 0.8f);}@Overrideprotected void onLayout(boolean changed, int left, int top, int right, int bottom) {vgLeft.layout(0, 0, width, height);vgMain.layout(mainLeft, 0, mainLeft + width, height);}/*** 拦截触摸事件* @param ev* @return*/@Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {return dragHelper.shouldInterceptTouchEvent(ev) && gestureDetector.onTouchEvent(ev);}/*** 将拦截的到事件给ViewDragHelper进行处理* @param e* @return*/@Overridepublic boolean onTouchEvent(MotionEvent e) {try {dragHelper.processTouchEvent(e);} catch (Exception ex) {ex.printStackTrace();}return false;}/*** 进行处理拖拽事件* @param mainLeft*/private void dispatchDragEvent(int mainLeft) {if (dragListener == null) {return;}float percent = mainLeft / (float) range;//滑动动画效果animateView(percent);//进行回调滑动的百分比dragListener.onDrag(percent);Status lastStatus = status;if (lastStatus != getStatus() && status == Status.CLOSE) {dragListener.onClose();} else if (lastStatus != getStatus() && status == Status.OPEN) {dragListener.onOpen();}}/*** 根据滑动的距离的比例,进行平移动画* @param percent*/private void animateView(float percent) {float f1 = 1 - percent * 0.5f;ViewHelper.setTranslationX(vgLeft, -vgLeft.getWidth() / 2.5f + vgLeft.getWidth() / 2.5f * percent);if (IS_SHOW_SHADOW) {//阴影效果视图大小进行缩放ViewHelper.setScaleX(ivShadow, f1 * 1.2f * (1 - percent * 0.10f));ViewHelper.setScaleY(ivShadow, f1 * 1.85f * (1 - percent * 0.10f));}}/*** 有加速度,当我们停止滑动的时候，该不会立即停止动画效果*/@Overridepublic void computeScroll() {if (dragHelper.continueSettling(true)) {ViewCompat.postInvalidateOnAnimation(this);}}/*** 页面状态(滑动,打开,关闭)*/public enum Status {DRAG, OPEN, CLOSE}/*** 页面状态设置* @return*/public Status getStatus() {if (mainLeft == 0) {status = Status.CLOSE;} else if (mainLeft == range) {status = Status.OPEN;} else {status = Status.DRAG;}return status;}public void open() {open(true);}public void open(boolean animate) {if (animate) {//继续滑动if (dragHelper.smoothSlideViewTo(vgMain, range, 0)) {ViewCompat.postInvalidateOnAnimation(this);}} else {vgMain.layout(range, 0, range * 2, height);dispatchDragEvent(range);}}public void close() {close(true);}public void close(boolean animate) {if (animate) {//继续滑动if (dragHelper.smoothSlideViewTo(vgMain, 0, 0)) {ViewCompat.postInvalidateOnAnimation(this);}} else {vgMain.layout(0, 0, width, height);dispatchDragEvent(0);}}
}

CustomRelativeLayout：

public class CustomRelativeLayout extends RelativeLayout {private DragLayout dl;public CustomRelativeLayout(Context context) {super(context);}public CustomRelativeLayout(Context context, AttributeSet attrs) {super(context, attrs);}public CustomRelativeLayout(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);}public void setDragLayout(DragLayout dl) {this.dl = dl;}@Overridepublic boolean onInterceptTouchEvent(MotionEvent event) {if (dl.getStatus() != DragLayout.Status.CLOSE) {return true;}return super.onInterceptTouchEvent(event);}@Overridepublic boolean onTouchEvent(MotionEvent event) {if (dl.getStatus() != DragLayout.Status.CLOSE) {if (event.getAction() == MotionEvent.ACTION_UP) {dl.close();}return true;}return super.onTouchEvent(event);}}

c沉浸式状态栏：BaseActivity：

public class BaseActivity extends FragmentActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);this.requestWindowFeature(Window.FEATURE_NO_TITLE);if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {//透明状态栏getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);//透明导航栏getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);}}/*** 设置沉浸式状态栏*/protected void setStatusBar() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {final ViewGroup linear_bar = (ViewGroup) findViewById(R.id.rl_title);final int statusHeight = getStatusBarHeight();linear_bar.post(new Runnable() {@Overridepublic void run() {int titleHeight = linear_bar.getHeight();android.widget.LinearLayout.LayoutParams params = (android.widget.LinearLayout.LayoutParams) linear_bar.getLayoutParams();params.height = statusHeight + titleHeight;linear_bar.setLayoutParams(params);}});}}/*** 获取状态栏的高度* @return*/protected int getStatusBarHeight(){try{Class c=Class.forName("com.android.internal.R$dimen");Object obj=c.newInstance();Field field=c.getField("status_bar_height");int x=Integer.parseInt(field.get(obj).toString());return  getResources().getDimensionPixelSize(x);}catch(Exception e){e.printStackTrace();}return 0;}}

MainActivity：

public class MainActivity extends BaseActivity {private DragLayout dl;private LinearLayout linearLayout;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initDragLayout();}private void initDragLayout() {dl = (DragLayout) findViewById(R.id.dl);linearLayout =(LinearLayout) findViewById(R.id.aaa);dl.setDragListener(new DragLayout.DragListener() {//界面打开的时候@Overridepublic void onOpen() {}//界面关闭的时候@Overridepublic void onClose() {}//界面滑动的时候@Overridepublic void onDrag(float percent) {}});}}

OneFragment：

public class OneFragment extends Fragment {private View mView;@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {if(mView==null){mView=inflater.inflate(R.layout.one_frag_layout,container,false);}return mView;}
}

b布局文件：
one_frag_layout.xml
LinearLayout布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical" android:layout_width="match_parent"android:layout_height="match_parent"android:gravity="center"android:id="@+id/aaa"><TextView
        android:text="界面"android:layout_gravity="center"android:layout_width="wrap_content"android:layout_height="wrap_content" />
LinearLayout>

one_frag_layout1.xml:
RelativeLayout布局

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical" android:layout_width="match_parent"android:layout_height="match_parent"android:gravity="center"><TextView
        android:text="主界面"android:layout_gravity="center"android:layout_width="wrap_content"android:layout_height="wrap_content" />
RelativeLayout>

activity.main.xml:

<com.包名.myapplication.widget.DragLayout
    xmlns:android="http://schemas.android.com/apk/res/android"android:id="@+id/dl"android:layout_width="match_parent"android:layout_height="match_parent"android:background="@android:color/transparent"><include layout="@layout/one_frag_layout1"/><com.包名.myapplication.widget.CustomRelativeLayout
        android:layout_width="match_parent"android:layout_height="match_parent"android:background="#FFFFFF"><LinearLayout
            android:layout_width="fill_parent"android:layout_height="fill_parent"android:orientation="vertical"><RelativeLayout
            android:id="@+id/rl_title"android:layout_width="match_parent"android:layout_height="49dp"android:gravity="bottom"android:background="#2aaced"><include layout="@layout/one_frag_layout"/>RelativeLayout><FrameLayout
            android:layout_width="fill_parent"android:layout_height="fill_parent"><fragment
               android:id="@+id/main_info_fragment"class="com.mieasy.myapplication.OneFragment"android:layout_width="fill_parent"android:layout_height="fill_parent"/>FrameLayout>LinearLayout>com.包名.myapplication.widget.CustomRelativeLayout>
com.包名.myapplication.widget.DragLayout>

w完。wan

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