Merge "Applying ChannelScrolling to remove calculateDragAngle" (c36303a6) · Commits · e / os / android_frameworks_base

core/java/android/webkit/WebViewClassic.java

+68 −66

Original line number	Diff line number	Diff line
		@@ -1258,6 +1258,40 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc

		mAutoFillData = new WebViewCore.AutoFillData();
		mEditTextScroller = new Scroller(context);

		// Calculate channel distance
		calculateChannelDistance(context);
		}

		/**
		* Calculate sChannelDistance based on the screen information.
		* @param context A Context object used to access application assets.
		*/
		private void calculateChannelDistance(Context context) {
		// The channel distance is adjusted for density and screen size
		final DisplayMetrics metrics = context.getResources().getDisplayMetrics();
		final double screenSize = Math.hypot((double)(metrics.widthPixels/metrics.densityDpi),
		(double)(metrics.heightPixels/metrics.densityDpi));
		if (screenSize < 3.0) {
		sChannelDistance = 16;
		} else if (screenSize < 5.0) {
		sChannelDistance = 22;
		} else if (screenSize < 7.0) {
		sChannelDistance = 28;
		} else {
		sChannelDistance = 34;
		}
		sChannelDistance = (int)(sChannelDistance * metrics.density);
		if (sChannelDistance < 16) sChannelDistance = 16;

		if (DebugFlags.WEB_VIEW) {
		Log.v(LOGTAG, "sChannelDistance : " + sChannelDistance
		+ ", density : " + metrics.density
		+ ", screenSize : " + screenSize
		+ ", metrics.heightPixels : " + metrics.heightPixels
		+ ", metrics.widthPixels : " + metrics.widthPixels
		+ ", metrics.densityDpi : " + metrics.densityDpi);
		}
		}

		// WebViewProvider bindings
		@@ -5716,31 +5750,12 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		return mWebViewPrivate.super_dispatchKeyEvent(event);
		}

		/*
		* Here is the snap align logic:
		* 1. If it starts nearly horizontally or vertically, snap align;
		* 2. If there is a dramitic direction change, let it go;
		*
		* Adjustable parameters. Angle is the radians on a unit circle, limited
		* to quadrant 1. Values range from 0f (horizontal) to PI/2 (vertical)
		*/
		private static final float HSLOPE_TO_START_SNAP = .25f;
		private static final float HSLOPE_TO_BREAK_SNAP = .4f;
		private static final float VSLOPE_TO_START_SNAP = 1.25f;
		private static final float VSLOPE_TO_BREAK_SNAP = .95f;
		/*
		* These values are used to influence the average angle when entering
		* snap mode. If is is the first movement entering snap, we set the average
		* to the appropriate ideal. If the user is entering into snap after the
		* first movement, then we average the average angle with these values.
		*/
		private static final float ANGLE_VERT = 2f;
		private static final float ANGLE_HORIZ = 0f;
		/*
		* The modified moving average weight.
		* Formula: MAV[t]=MAV[t-1] + (P[t]-MAV[t-1])/n
		*/
		private static final float MMA_WEIGHT_N = 5;
		private static final int SNAP_BOUND = 16;
		private static int sChannelDistance = 16;
		private int mFirstTouchX = -1; // the first touched point
		private int mFirstTouchY = -1;
		private int mDistanceX = 0;
		private int mDistanceY = 0;

		private boolean inFullScreenMode() {
		return mFullScreenHolder != null;
		@@ -5830,12 +5845,6 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		}
		}

		private float calculateDragAngle(int dx, int dy) {
		dx = Math.abs(dx);
		dy = Math.abs(dy);
		return (float) Math.atan2(dy, dx);
		}

		/*
		* Common code for single touch and multi-touch.
		* (x, y) denotes current focus point, which is the touch point for single touch
		@@ -5861,6 +5870,12 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		switch (action) {
		case MotionEvent.ACTION_DOWN: {
		mConfirmMove = false;

		// Channel Scrolling
		mFirstTouchX = x;
		mFirstTouchY = y;
		mDistanceX = mDistanceY = 0;

		if (!mEditTextScroller.isFinished()) {
		mEditTextScroller.abortAnimation();
		}
		@@ -5998,20 +6013,16 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		break;
		}

		// Only lock dragging to one axis if we don't have a scale in progress.
		// Scaling implies free-roaming movement. Note this is only ever a question
		// if mZoomManager.supportsPanDuringZoom() is true.
		mAverageAngle = calculateDragAngle(deltaX, deltaY);
		if (detector == null \|\| !detector.isInProgress()) {
		// if it starts nearly horizontal or vertical, enforce it
		if (mAverageAngle < HSLOPE_TO_START_SNAP) {
		mSnapScrollMode = SNAP_X;
		mSnapPositive = deltaX > 0;
		mAverageAngle = ANGLE_HORIZ;
		} else if (mAverageAngle > VSLOPE_TO_START_SNAP) {
		if ((detector == null \|\| !detector.isInProgress())
		&& SNAP_NONE == mSnapScrollMode) {
		int ax = Math.abs(x - mFirstTouchX);
		int ay = Math.abs(y - mFirstTouchY);
		if (ax < SNAP_BOUND && ay < SNAP_BOUND) {
		break;
		} else if (ax < SNAP_BOUND) {
		mSnapScrollMode = SNAP_Y;
		mSnapPositive = deltaY > 0;
		mAverageAngle = ANGLE_VERT;
		} else if (ay < SNAP_BOUND) {
		mSnapScrollMode = SNAP_X;
		}
		}

		@@ -6030,31 +6041,21 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		if (deltaX == 0 && deltaY == 0) {
		keepScrollBarsVisible = true;
		} else {
		mAverageAngle +=
		(calculateDragAngle(deltaX, deltaY) - mAverageAngle)
		/ MMA_WEIGHT_N;
		if (mSnapScrollMode != SNAP_NONE) {
		if (mSnapScrollMode == SNAP_Y) {
		// radical change means getting out of snap mode
		if (mAverageAngle < VSLOPE_TO_BREAK_SNAP) {
		mSnapScrollMode = SNAP_NONE;
		}
		}
		if (mSnapScrollMode == SNAP_X \|\| mSnapScrollMode == SNAP_Y) {
		mDistanceX += Math.abs(deltaX);
		mDistanceY += Math.abs(deltaY);
		if (mSnapScrollMode == SNAP_X) {
		// radical change means getting out of snap mode
		if (mAverageAngle > HSLOPE_TO_BREAK_SNAP) {
		if (mDistanceY > sChannelDistance) {
		mSnapScrollMode = SNAP_NONE;
		}
		} else if (mDistanceX > sChannelDistance) {
		mDistanceX = mDistanceY = 0;
		}
		} else {
		if (mAverageAngle < HSLOPE_TO_START_SNAP) {
		mSnapScrollMode = SNAP_X;
		mSnapPositive = deltaX > 0;
		mAverageAngle = (mAverageAngle + ANGLE_HORIZ) / 2;
		} else if (mAverageAngle > VSLOPE_TO_START_SNAP) {
		mSnapScrollMode = SNAP_Y;
		mSnapPositive = deltaY > 0;
		mAverageAngle = (mAverageAngle + ANGLE_VERT) / 2;
		if (mDistanceX > sChannelDistance) {
		mSnapScrollMode = SNAP_NONE;
		} else if (mDistanceY > sChannelDistance) {
		mDistanceX = mDistanceY = 0;
		}
		}
		}
		if (mSnapScrollMode != SNAP_NONE) {
		@@ -6089,6 +6090,7 @@ public final class WebViewClassic implements WebViewProvider, WebViewProvider.Sc
		break;
		}
		case MotionEvent.ACTION_UP: {
		mFirstTouchX = mFirstTouchY = -1;
		if (mIsEditingText && mSelectionStarted) {
		endScrollEdit();
		mPrivateHandler.sendEmptyMessageDelayed(SCROLL_HANDLE_INTO_VIEW,