Using velocity tracker for computing the velocity of motion events (4d8ec15f) · Commits · e / os / BlissLauncher3

quickstep/src/com/android/launcher3/uioverrides/TaskViewTouchController.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -220,7 +220,7 @@ public abstract class TaskViewTouchController<T extends BaseDraggingActivity>
		}

		@Override
		public boolean onDrag(float displacement, float velocity) {
		public boolean onDrag(float displacement) {
		float totalDisplacement = displacement + mDisplacementShift;
		boolean isGoingUp =
		totalDisplacement == 0 ? mCurrentAnimationIsGoingUp : totalDisplacement < 0;

src/com/android/launcher3/notification/NotificationMainView.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -179,7 +179,7 @@ public class NotificationMainView extends FrameLayout implements SwipeDetector.L


		@Override
		public boolean onDrag(float displacement, float velocity) {
		public boolean onDrag(float displacement) {
		setContentTranslation(canChildBeDismissed()
		? displacement : OverScroll.dampedScroll(displacement, getWidth()));
		mContentTranslateAnimator.cancel();

src/com/android/launcher3/touch/AbstractStateChangeTouchController.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -256,7 +256,7 @@ public abstract class AbstractStateChangeTouchController
		}

		@Override
		public boolean onDrag(float displacement, float velocity) {
		public boolean onDrag(float displacement) {
		float deltaProgress = mProgressMultiplier * (displacement - mDisplacementShift);
		float progress = deltaProgress + mStartProgress;
		updateProgress(progress);

src/com/android/launcher3/touch/SwipeDetector.java

+40 −58

Original line number	Diff line number	Diff line
		@@ -21,6 +21,7 @@ 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 androidx.annotation.NonNull;
		@@ -52,12 +53,6 @@ public class SwipeDetector {
		*/
		public static final float RELEASE_VELOCITY_PX_MS = 1.0f;

		/**
		* The time constant used to calculate dampening in the low-pass filter of scroll velocity.
		* Cutoff frequency is set at 10 Hz.
		*/
		public static final float SCROLL_VELOCITY_DAMPENING_RC = 1000f / (2f * (float) Math.PI * 10);

		/* Scroll state, this is set to true during dragging and animation. */
		private ScrollState mState = ScrollState.IDLE;

		@@ -75,6 +70,8 @@ public class SwipeDetector {
		* 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);
		}

		public static final Direction VERTICAL = new Direction() {
		@@ -88,6 +85,11 @@ public class SwipeDetector {
		float getActiveTouchSlop(MotionEvent ev, int pointerIndex, PointF downPos) {
		return Math.abs(ev.getX(pointerIndex) - downPos.x);
		}

		@Override
		float getVelocity(VelocityTracker tracker) {
		return tracker.getYVelocity();
		}
		};

		public static final Direction HORIZONTAL = new Direction() {
		@@ -101,6 +103,11 @@ public class SwipeDetector {
		float getActiveTouchSlop(MotionEvent ev, int pointerIndex, PointF downPos) {
		return Math.abs(ev.getY(pointerIndex) - downPos.y);
		}

		@Override
		float getVelocity(VelocityTracker tracker) {
		return tracker.getXVelocity();
		}
		};

		//------------------- ScrollState transition diagram -----------------------------------
		@@ -151,16 +158,16 @@ public class SwipeDetector {

		private final PointF mDownPos = new PointF();
		private final PointF mLastPos = new PointF();
		private Direction mDir;
		private final Direction mDir;

		private final float mTouchSlop;
		private final float mMaxVelocity;

		/* Client of this gesture detector can register a callback. */
		private final Listener mListener;

		private long mCurrentMillis;
		private VelocityTracker mVelocityTracker;

		private float mVelocity;
		private float mLastDisplacement;
		private float mDisplacement;

		@@ -170,24 +177,22 @@ public class SwipeDetector {
		public interface Listener {
		void onDragStart(boolean start);

		boolean onDrag(float displacement, float velocity);
		boolean onDrag(float displacement);

		void onDragEnd(float velocity, boolean fling);
		}

		public SwipeDetector(@NonNull Context context, @NonNull Listener l, @NonNull Direction dir) {
		this(ViewConfiguration.get(context).getScaledTouchSlop(), l, dir);
		this(ViewConfiguration.get(context), l, dir);
		}

		@VisibleForTesting
		protected SwipeDetector(float touchSlope, @NonNull Listener l, @NonNull Direction dir) {
		mTouchSlop = touchSlope;
		protected SwipeDetector(@NonNull ViewConfiguration config, @NonNull Listener l,
		@NonNull Direction dir) {
		mListener = l;
		mDir = dir;
		}

		public void updateDirection(Direction dir) {
		mDir = dir;
		mTouchSlop = config.getScaledTouchSlop();
		mMaxVelocity = config.getScaledMaximumFlingVelocity();
		}

		public void setDetectableScrollConditions(int scrollDirectionFlags, boolean ignoreSlop) {
		@@ -215,14 +220,22 @@ public class SwipeDetector {
		}

		public boolean onTouchEvent(MotionEvent ev) {
		switch (ev.getActionMasked()) {
		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;
		mVelocity = 0;

		if (mState == ScrollState.SETTLING && mIgnoreSlopWhenSettling) {
		setState(ScrollState.DRAGGING);
		@@ -247,8 +260,6 @@ public class SwipeDetector {
		break;
		}
		mDisplacement = mDir.getDisplacement(ev, pointerIndex, mDownPos);
		computeVelocity(mDir.getDisplacement(ev, pointerIndex, mLastPos),
		ev.getEventTime());

		// handle state and listener calls.
		if (mState != ScrollState.DRAGGING && shouldScrollStart(ev, pointerIndex)) {
		@@ -265,6 +276,8 @@ public class SwipeDetector {
		if (mState == ScrollState.DRAGGING) {
		setState(ScrollState.SETTLING);
		}
		mVelocityTracker.recycle();
		mVelocityTracker = null;
		break;
		default:
		break;
		@@ -308,55 +321,24 @@ public class SwipeDetector {
		private boolean reportDragging() {
		if (mDisplacement != mLastDisplacement) {
		if (DBG) {
		Log.d(TAG, String.format("onDrag disp=%.1f, velocity=%.1f",
		mDisplacement, mVelocity));
		Log.d(TAG, String.format("onDrag disp=%.1f", mDisplacement));
		}

		mLastDisplacement = mDisplacement;
		return mListener.onDrag(mDisplacement - mSubtractDisplacement, mVelocity);
		return mListener.onDrag(mDisplacement - mSubtractDisplacement);
		}
		return true;
		}

		private void reportDragEnd() {
		mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity);
		float velocity = mDir.getVelocity(mVelocityTracker) / 1000;
		if (DBG) {
		Log.d(TAG, String.format("onScrollEnd disp=%.1f, velocity=%.1f",
		mDisplacement, mVelocity));
		}
		mListener.onDragEnd(mVelocity, Math.abs(mVelocity) > RELEASE_VELOCITY_PX_MS);

		mDisplacement, velocity));
		}

		/**
		* Computes the damped velocity.
		*/
		public float computeVelocity(float delta, long currentMillis) {
		long previousMillis = mCurrentMillis;
		mCurrentMillis = currentMillis;

		float deltaTimeMillis = mCurrentMillis - previousMillis;
		float velocity = (deltaTimeMillis > 0) ? (delta / deltaTimeMillis) : 0;
		if (Math.abs(mVelocity) < 0.001f) {
		mVelocity = velocity;
		} else {
		float alpha = computeDampeningFactor(deltaTimeMillis);
		mVelocity = interpolate(mVelocity, velocity, alpha);
		}
		return mVelocity;
		}

		/**
		* Returns a time-dependent dampening factor using delta time.
		*/
		private static float computeDampeningFactor(float deltaTime) {
		return deltaTime / (SCROLL_VELOCITY_DAMPENING_RC + deltaTime);
		}

		/**
		* Returns the linear interpolation between two values
		*/
		public static float interpolate(float from, float to, float alpha) {
		return (1.0f - alpha) * from + alpha * to;
		mListener.onDragEnd(velocity, Math.abs(velocity) > RELEASE_VELOCITY_PX_MS);
		}

		public static long calculateDuration(float velocity, float progressNeeded) {

src/com/android/launcher3/views/AbstractSlideInView.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -128,7 +128,7 @@ public abstract class AbstractSlideInView extends AbstractFloatingView
		public void onDragStart(boolean start) { }

		@Override
		public boolean onDrag(float displacement, float velocity) {
		public boolean onDrag(float displacement) {
		float range = mContent.getHeight();
		displacement = Utilities.boundToRange(displacement, 0, range);
		setTranslationShift(displacement / range);