diff options
Diffstat (limited to 'src/com/android/launcher3/touch/SwipeDetector.java')
| -rw-r--r-- | src/com/android/launcher3/touch/SwipeDetector.java | 407 |
1 files changed, 0 insertions, 407 deletions
diff --git a/src/com/android/launcher3/touch/SwipeDetector.java b/src/com/android/launcher3/touch/SwipeDetector.java deleted file mode 100644 index 3777a41ad..000000000 --- a/src/com/android/launcher3/touch/SwipeDetector.java +++ /dev/null @@ -1,407 +0,0 @@ -/* - * Copyright (C) 2017 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.launcher3.touch; - -import static android.view.MotionEvent.INVALID_POINTER_ID; - -import android.content.Context; -import android.graphics.PointF; -import android.util.Log; -import android.view.MotionEvent; -import android.view.VelocityTracker; -import android.view.ViewConfiguration; - -import com.android.launcher3.Utilities; -import com.android.launcher3.testing.TestProtocol; - -import androidx.annotation.NonNull; -import androidx.annotation.VisibleForTesting; - -/** - * One dimensional scroll/drag/swipe gesture detector. - * - * Definition of swipe is different from android system in that this detector handles - * 'swipe to dismiss', 'swiping up/down a container' but also keeps scrolling state before - * swipe action happens - */ -public class SwipeDetector { - - private static final boolean DBG = false; - private static final String TAG = "SwipeDetector"; - - private int mScrollConditions; - public static final int DIRECTION_POSITIVE = 1 << 0; - public static final int DIRECTION_NEGATIVE = 1 << 1; - public static final int DIRECTION_BOTH = DIRECTION_NEGATIVE | DIRECTION_POSITIVE; - - private static final float ANIMATION_DURATION = 1200; - - protected int mActivePointerId = INVALID_POINTER_ID; - - /** - * The minimum release velocity in pixels per millisecond that triggers fling.. - */ - public static final float RELEASE_VELOCITY_PX_MS = 1.0f; - - /* Scroll state, this is set to true during dragging and animation. */ - private ScrollState mState = ScrollState.IDLE; - - enum ScrollState { - IDLE, - DRAGGING, // onDragStart, onDrag - SETTLING // onDragEnd - } - - public static abstract class Direction { - - abstract float getDisplacement(MotionEvent ev, int pointerIndex, PointF refPoint, - boolean isRtl); - - /** - * Distance in pixels a touch can wander before we think the user is scrolling. - */ - abstract float getActiveTouchSlop(MotionEvent ev, int pointerIndex, PointF downPos); - - abstract float getVelocity(VelocityTracker tracker, boolean isRtl); - - abstract boolean isPositive(float displacement); - - abstract boolean isNegative(float displacement); - } - - public static final Direction VERTICAL = new Direction() { - - @Override - float getDisplacement(MotionEvent ev, int pointerIndex, PointF refPoint, boolean isRtl) { - return ev.getY(pointerIndex) - refPoint.y; - } - - @Override - float getActiveTouchSlop(MotionEvent ev, int pointerIndex, PointF downPos) { - return Math.abs(ev.getX(pointerIndex) - downPos.x); - } - - @Override - float getVelocity(VelocityTracker tracker, boolean isRtl) { - return tracker.getYVelocity(); - } - - @Override - boolean isPositive(float displacement) { - // Up - return displacement < 0; - } - - @Override - boolean isNegative(float displacement) { - // Down - return displacement > 0; - } - }; - - public static final Direction HORIZONTAL = new Direction() { - - @Override - float getDisplacement(MotionEvent ev, int pointerIndex, PointF refPoint, boolean isRtl) { - float displacement = ev.getX(pointerIndex) - refPoint.x; - if (isRtl) { - displacement = -displacement; - } - return displacement; - } - - @Override - float getActiveTouchSlop(MotionEvent ev, int pointerIndex, PointF downPos) { - return Math.abs(ev.getY(pointerIndex) - downPos.y); - } - - @Override - float getVelocity(VelocityTracker tracker, boolean isRtl) { - float velocity = tracker.getXVelocity(); - if (isRtl) { - velocity = -velocity; - } - return velocity; - } - - @Override - boolean isPositive(float displacement) { - // Right - return displacement > 0; - } - - @Override - boolean isNegative(float displacement) { - // Left - return displacement < 0; - } - }; - - //------------------- ScrollState transition diagram ----------------------------------- - // - // IDLE -> (mDisplacement > mTouchSlop) -> DRAGGING - // DRAGGING -> (MotionEvent#ACTION_UP, MotionEvent#ACTION_CANCEL) -> SETTLING - // SETTLING -> (MotionEvent#ACTION_DOWN) -> DRAGGING - // SETTLING -> (View settled) -> IDLE - - private void setState(ScrollState newState) { - if (DBG) { - Log.d(TAG, "setState:" + mState + "->" + newState); - } - // onDragStart and onDragEnd is reported ONLY on state transition - if (newState == ScrollState.DRAGGING) { - initializeDragging(); - if (mState == ScrollState.IDLE) { - reportDragStart(false /* recatch */); - } else if (mState == ScrollState.SETTLING) { - reportDragStart(true /* recatch */); - } - } - if (newState == ScrollState.SETTLING) { - reportDragEnd(); - } - - mState = newState; - } - - public boolean isDraggingOrSettling() { - return mState == ScrollState.DRAGGING || mState == ScrollState.SETTLING; - } - - public int getDownX() { - return (int) mDownPos.x; - } - - public int getDownY() { - return (int) mDownPos.y; - } - /** - * There's no touch and there's no animation. - */ - public boolean isIdleState() { - return mState == ScrollState.IDLE; - } - - public boolean isSettlingState() { - return mState == ScrollState.SETTLING; - } - - public boolean isDraggingState() { - return mState == ScrollState.DRAGGING; - } - - private final PointF mDownPos = new PointF(); - private final PointF mLastPos = new PointF(); - private final Direction mDir; - private final boolean mIsRtl; - - private final float mTouchSlop; - private final float mMaxVelocity; - - /* Client of this gesture detector can register a callback. */ - private final Listener mListener; - - private VelocityTracker mVelocityTracker; - - private float mLastDisplacement; - private float mDisplacement; - - private float mSubtractDisplacement; - private boolean mIgnoreSlopWhenSettling; - - public interface Listener { - void onDragStart(boolean start); - - boolean onDrag(float displacement); - - default boolean onDrag(float displacement, MotionEvent event) { - return onDrag(displacement); - } - - void onDragEnd(float velocity, boolean fling); - } - - public SwipeDetector(@NonNull Context context, @NonNull Listener l, @NonNull Direction dir) { - this(ViewConfiguration.get(context), l, dir, Utilities.isRtl(context.getResources())); - } - - @VisibleForTesting - protected SwipeDetector(@NonNull ViewConfiguration config, @NonNull Listener l, - @NonNull Direction dir, boolean isRtl) { - mListener = l; - mDir = dir; - mIsRtl = isRtl; - mTouchSlop = config.getScaledTouchSlop(); - mMaxVelocity = config.getScaledMaximumFlingVelocity(); - } - - public void setDetectableScrollConditions(int scrollDirectionFlags, boolean ignoreSlop) { - mScrollConditions = scrollDirectionFlags; - mIgnoreSlopWhenSettling = ignoreSlop; - } - - public int getScrollDirections() { - return mScrollConditions; - } - - private boolean shouldScrollStart(MotionEvent ev, int pointerIndex) { - // reject cases where the angle or slop condition is not met. - if (Math.max(mDir.getActiveTouchSlop(ev, pointerIndex, mDownPos), mTouchSlop) - > Math.abs(mDisplacement)) { - return false; - } - - // Check if the client is interested in scroll in current direction. - if (((mScrollConditions & DIRECTION_NEGATIVE) > 0 && mDir.isNegative(mDisplacement)) || - ((mScrollConditions & DIRECTION_POSITIVE) > 0 && mDir.isPositive(mDisplacement))) { - return true; - } - return false; - } - - public boolean onTouchEvent(MotionEvent ev) { - int actionMasked = ev.getActionMasked(); - if (actionMasked == MotionEvent.ACTION_DOWN && mVelocityTracker != null) { - mVelocityTracker.clear(); - } - if (mVelocityTracker == null) { - mVelocityTracker = VelocityTracker.obtain(); - } - mVelocityTracker.addMovement(ev); - - switch (actionMasked) { - case MotionEvent.ACTION_DOWN: - mActivePointerId = ev.getPointerId(0); - mDownPos.set(ev.getX(), ev.getY()); - mLastPos.set(mDownPos); - mLastDisplacement = 0; - mDisplacement = 0; - - if (mState == ScrollState.SETTLING && mIgnoreSlopWhenSettling) { - setState(ScrollState.DRAGGING); - } - break; - //case MotionEvent.ACTION_POINTER_DOWN: - case MotionEvent.ACTION_POINTER_UP: - int ptrIdx = ev.getActionIndex(); - int ptrId = ev.getPointerId(ptrIdx); - if (ptrId == mActivePointerId) { - final int newPointerIdx = ptrIdx == 0 ? 1 : 0; - mDownPos.set( - ev.getX(newPointerIdx) - (mLastPos.x - mDownPos.x), - ev.getY(newPointerIdx) - (mLastPos.y - mDownPos.y)); - mLastPos.set(ev.getX(newPointerIdx), ev.getY(newPointerIdx)); - mActivePointerId = ev.getPointerId(newPointerIdx); - } - break; - case MotionEvent.ACTION_MOVE: - int pointerIndex = ev.findPointerIndex(mActivePointerId); - if (pointerIndex == INVALID_POINTER_ID) { - break; - } - mDisplacement = mDir.getDisplacement(ev, pointerIndex, mDownPos, mIsRtl); - - // handle state and listener calls. - if (mState != ScrollState.DRAGGING && shouldScrollStart(ev, pointerIndex)) { - setState(ScrollState.DRAGGING); - } - if (mState == ScrollState.DRAGGING) { - reportDragging(ev); - } - mLastPos.set(ev.getX(pointerIndex), ev.getY(pointerIndex)); - break; - case MotionEvent.ACTION_CANCEL: - case MotionEvent.ACTION_UP: - // These are synthetic events and there is no need to update internal values. - if (mState == ScrollState.DRAGGING) { - setState(ScrollState.SETTLING); - } - mVelocityTracker.recycle(); - mVelocityTracker = null; - break; - default: - break; - } - return true; - } - - public void finishedScrolling() { - setState(ScrollState.IDLE); - } - - private boolean reportDragStart(boolean recatch) { - mListener.onDragStart(!recatch); - if (DBG) { - Log.d(TAG, "onDragStart recatch:" + recatch); - } - return true; - } - - private void initializeDragging() { - if (mState == ScrollState.SETTLING && mIgnoreSlopWhenSettling) { - mSubtractDisplacement = 0; - } - if (mDisplacement > 0) { - mSubtractDisplacement = mTouchSlop; - } else { - mSubtractDisplacement = -mTouchSlop; - } - } - - /** - * Returns if the start drag was towards the positive direction or negative. - * - * @see #setDetectableScrollConditions(int, boolean) - * @see #DIRECTION_BOTH - */ - public boolean wasInitialTouchPositive() { - return mDir.isPositive(mSubtractDisplacement); - } - - private boolean reportDragging(MotionEvent event) { - if (mDisplacement != mLastDisplacement) { - if (DBG) { - Log.d(TAG, String.format("onDrag disp=%.1f", mDisplacement)); - } - - mLastDisplacement = mDisplacement; - return mListener.onDrag(mDisplacement - mSubtractDisplacement, event); - } - return true; - } - - private void reportDragEnd() { - mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity); - float velocity = mDir.getVelocity(mVelocityTracker, mIsRtl) / 1000; - if (DBG) { - Log.d(TAG, String.format("onScrollEnd disp=%.1f, velocity=%.1f", - mDisplacement, velocity)); - } - - mListener.onDragEnd(velocity, Math.abs(velocity) > RELEASE_VELOCITY_PX_MS); - } - - public static long calculateDuration(float velocity, float progressNeeded) { - // TODO: make these values constants after tuning. - float velocityDivisor = Math.max(2f, Math.abs(0.5f * velocity)); - float travelDistance = Math.max(0.2f, progressNeeded); - long duration = (long) Math.max(100, ANIMATION_DURATION / velocityDivisor * travelDistance); - if (DBG) { - Log.d(TAG, String.format("calculateDuration=%d, v=%f, d=%f", duration, velocity, progressNeeded)); - } - return duration; - } -} |