/** This function must be called from the UI thread. */
public void abortAnimation() {
checkMainThread();
// this happens when gecko changes the viewport on us or if the device is rotated.
// if that's the case, abort any animation in progress and re-zoom so that the page
// snaps to edges. for other cases (where the user's finger(s) are down) don't do
// anything special.
switch (mState) {
case FLING:
mX.stopFling();
mY.stopFling();
// fall through
case BOUNCE:
case ANIMATED_ZOOM:
// the zoom that's in progress likely makes no sense any more (such as if
// the screen orientation changed) so abort it
setState(PanZoomState.NOTHING);
// fall through
case NOTHING:
// Don't do animations here; they're distracting and can cause flashes on page
// transitions.
synchronized (mTarget.getLock()) {
mTarget.setViewportMetrics(getValidViewportMetrics());
}
break;
}
}
public void handleMessage(String event, JSONObject message) {
try {
if (MESSAGE_ZOOM_RECT.equals(event)) {
float x = (float) message.getDouble("x");
float y = (float) message.getDouble("y");
final RectF zoomRect =
new RectF(x, y, x + (float) message.getDouble("w"), y + (float) message.getDouble("h"));
mTarget.post(
new Runnable() {
public void run() {
animatedZoomTo(zoomRect);
}
});
} else if (MESSAGE_ZOOM_PAGE.equals(event)) {
ImmutableViewportMetrics metrics = getMetrics();
RectF cssPageRect = metrics.getCssPageRect();
RectF viewableRect = metrics.getCssViewport();
float y = viewableRect.top;
// attempt to keep zoom keep focused on the center of the viewport
float newHeight = viewableRect.height() * cssPageRect.width() / viewableRect.width();
float dh = viewableRect.height() - newHeight; // increase in the height
final RectF r = new RectF(0.0f, y + dh / 2, cssPageRect.width(), y + dh / 2 + newHeight);
mTarget.post(
new Runnable() {
public void run() {
animatedZoomTo(r);
}
});
}
} catch (Exception e) {
Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
}
}
/** This must be called on the UI thread. */
public void pageRectUpdated() {
if (mState == PanZoomState.NOTHING) {
synchronized (mTarget.getLock()) {
ImmutableViewportMetrics validated = getValidViewportMetrics();
if (!getMetrics().fuzzyEquals(validated)) {
// page size changed such that we are now in overscroll. snap to the
// the nearest valid viewport
mTarget.setViewportMetrics(validated);
}
}
}
}
private boolean onTouchStart(MotionEvent event) {
// user is taking control of movement, so stop
// any auto-movement we have going
stopAnimationTimer();
switch (mState) {
case ANIMATED_ZOOM:
// We just interrupted a double-tap animation, so force a redraw in
// case this touchstart is just a tap that doesn't end up triggering
// a redraw
mTarget.setForceRedraw();
// fall through
case FLING:
case BOUNCE:
case NOTHING:
case WAITING_LISTENERS:
startTouch(event.getX(0), event.getY(0), event.getEventTime());
return false;
case TOUCHING:
case PANNING:
case PANNING_LOCKED:
case PANNING_HOLD:
case PANNING_HOLD_LOCKED:
case PINCHING:
Log.e(LOGTAG, "Received impossible touch down while in " + mState);
return false;
}
Log.e(LOGTAG, "Unhandled case " + mState + " in onTouchStart");
return false;
}
@Override
public boolean onDoubleTap(MotionEvent motionEvent) {
if (mTarget.getZoomConstraints().getAllowZoom()) {
sendPointToGecko("Gesture:DoubleTap", motionEvent);
}
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent motionEvent) {
// When zooming is disabled, we handle this in onSingleTapUp.
if (mTarget.getZoomConstraints().getAllowZoom()) {
sendPointToGecko("Gesture:SingleTap", motionEvent);
}
return true;
}
private void finishAnimation() {
checkMainThread();
stopAnimationTimer();
// Force a viewport synchronisation
mTarget.setForceRedraw();
}
@Override
public boolean onSingleTapUp(MotionEvent motionEvent) {
// When zooming is enabled, wait to see if there's a double-tap.
if (!mTarget.getZoomConstraints().getAllowZoom()) {
sendPointToGecko("Gesture:SingleTap", motionEvent);
}
// return false because we still want to get the ACTION_UP event that triggers this
return false;
}
private ImmutableViewportMetrics getValidViewportMetrics(
ImmutableViewportMetrics viewportMetrics) {
/* First, we adjust the zoom factor so that we can make no overscrolled area visible. */
float zoomFactor = viewportMetrics.zoomFactor;
RectF pageRect = viewportMetrics.getPageRect();
RectF viewport = viewportMetrics.getViewport();
float focusX = viewport.width() / 2.0f;
float focusY = viewport.height() / 2.0f;
float minZoomFactor = 0.0f;
float maxZoomFactor = MAX_ZOOM;
ZoomConstraints constraints = mTarget.getZoomConstraints();
if (constraints.getMinZoom() > 0) minZoomFactor = constraints.getMinZoom();
if (constraints.getMaxZoom() > 0) maxZoomFactor = constraints.getMaxZoom();
if (!constraints.getAllowZoom()) {
// If allowZoom is false, clamp to the default zoom level.
maxZoomFactor = minZoomFactor = constraints.getDefaultZoom();
}
// Ensure minZoomFactor keeps the page at least as big as the viewport.
if (pageRect.width() > 0) {
float scaleFactor = viewport.width() / pageRect.width();
minZoomFactor = Math.max(minZoomFactor, zoomFactor * scaleFactor);
if (viewport.width() > pageRect.width()) focusX = 0.0f;
}
if (pageRect.height() > 0) {
float scaleFactor = viewport.height() / pageRect.height();
minZoomFactor = Math.max(minZoomFactor, zoomFactor * scaleFactor);
if (viewport.height() > pageRect.height()) focusY = 0.0f;
}
maxZoomFactor = Math.max(maxZoomFactor, minZoomFactor);
if (zoomFactor < minZoomFactor) {
// if one (or both) of the page dimensions is smaller than the viewport,
// zoom using the top/left as the focus on that axis. this prevents the
// scenario where, if both dimensions are smaller than the viewport, but
// by different scale factors, we end up scrolled to the end on one axis
// after applying the scale
PointF center = new PointF(focusX, focusY);
viewportMetrics = viewportMetrics.scaleTo(minZoomFactor, center);
} else if (zoomFactor > maxZoomFactor) {
PointF center = new PointF(viewport.width() / 2.0f, viewport.height() / 2.0f);
viewportMetrics = viewportMetrics.scaleTo(maxZoomFactor, center);
}
/* Now we pan to the right origin. */
viewportMetrics = viewportMetrics.clamp();
return viewportMetrics;
}
private void updatePosition() {
mX.displace();
mY.displace();
PointF displacement = resetDisplacement();
if (FloatUtils.fuzzyEquals(displacement.x, 0.0f)
&& FloatUtils.fuzzyEquals(displacement.y, 0.0f)) {
return;
}
if (!mSubscroller.scrollBy(displacement)) {
synchronized (mTarget.getLock()) {
scrollBy(displacement.x, displacement.y);
}
}
}
private void sendPointToGecko(String event, MotionEvent motionEvent) {
String json;
try {
PointF point = new PointF(motionEvent.getX(), motionEvent.getY());
point = mTarget.convertViewPointToLayerPoint(point);
if (point == null) {
return;
}
json = PointUtils.toJSON(point).toString();
} catch (Exception e) {
Log.e(LOGTAG, "Unable to convert point to JSON for " + event, e);
return;
}
GeckoAppShell.sendEventToGecko(GeckoEvent.createBroadcastEvent(event, json));
}
/*
* Zooming
*/
@Override
public boolean onScaleBegin(SimpleScaleGestureDetector detector) {
if (mState == PanZoomState.ANIMATED_ZOOM) return false;
if (!mTarget.getZoomConstraints().getAllowZoom()) return false;
setState(PanZoomState.PINCHING);
mLastZoomFocus = new PointF(detector.getFocusX(), detector.getFocusY());
cancelTouch();
GeckoAppShell.sendEventToGecko(
GeckoEvent.createNativeGestureEvent(
GeckoEvent.ACTION_MAGNIFY_START, mLastZoomFocus, getMetrics().zoomFactor));
return true;
}
/* Performs a bounce-back animation to the given viewport metrics. */
private void bounce(ImmutableViewportMetrics metrics) {
stopAnimationTimer();
ImmutableViewportMetrics bounceStartMetrics = getMetrics();
if (bounceStartMetrics.fuzzyEquals(metrics)) {
setState(PanZoomState.NOTHING);
return;
}
// At this point we have already set mState to BOUNCE or ANIMATED_ZOOM, so
// getRedrawHint() is returning false. This means we can safely call
// setAnimationTarget to set the new final display port and not have it get
// clobbered by display ports from intermediate animation frames.
mTarget.setAnimationTarget(metrics);
startAnimationTimer(new BounceRunnable(bounceStartMetrics, metrics));
}
@Override
public void onScaleEnd(SimpleScaleGestureDetector detector) {
if (mState == PanZoomState.ANIMATED_ZOOM) return;
// switch back to the touching state
startTouch(detector.getFocusX(), detector.getFocusY(), detector.getEventTime());
// Force a viewport synchronisation
mTarget.setForceRedraw();
PointF point = new PointF(detector.getFocusX(), detector.getFocusY());
GeckoEvent event =
GeckoEvent.createNativeGestureEvent(
GeckoEvent.ACTION_MAGNIFY_END, point, getMetrics().zoomFactor);
if (event == null) {
return;
}
GeckoAppShell.sendEventToGecko(event);
}
/**
* Scales the viewport, keeping the given focus point in the same place before and after the scale
* operation. You must hold the monitor while calling this.
*/
private void scaleWithFocus(float zoomFactor, PointF focus) {
ImmutableViewportMetrics viewportMetrics = getMetrics();
viewportMetrics = viewportMetrics.scaleTo(zoomFactor, focus);
mTarget.setViewportMetrics(viewportMetrics);
}
@Override
public boolean onScale(SimpleScaleGestureDetector detector) {
if (GeckoApp.mAppContext == null || GeckoApp.mAppContext.mDOMFullScreen) return false;
if (mState != PanZoomState.PINCHING) return false;
float prevSpan = detector.getPreviousSpan();
if (FloatUtils.fuzzyEquals(prevSpan, 0.0f)) {
// let's eat this one to avoid setting the new zoom to infinity (bug 711453)
return true;
}
float spanRatio = detector.getCurrentSpan() / prevSpan;
/*
* Apply edge resistance if we're zoomed out smaller than the page size by scaling the zoom
* factor toward 1.0.
*/
float resistance = Math.min(mX.getEdgeResistance(true), mY.getEdgeResistance(true));
if (spanRatio > 1.0f) spanRatio = 1.0f + (spanRatio - 1.0f) * resistance;
else spanRatio = 1.0f - (1.0f - spanRatio) * resistance;
synchronized (mTarget.getLock()) {
float newZoomFactor = getMetrics().zoomFactor * spanRatio;
float minZoomFactor = 0.0f;
float maxZoomFactor = MAX_ZOOM;
ZoomConstraints constraints = mTarget.getZoomConstraints();
if (constraints.getMinZoom() > 0) minZoomFactor = constraints.getMinZoom();
if (constraints.getMaxZoom() > 0) maxZoomFactor = constraints.getMaxZoom();
if (newZoomFactor < minZoomFactor) {
// apply resistance when zooming past minZoomFactor,
// such that it asymptotically reaches minZoomFactor / 2.0
// but never exceeds that
final float rate = 0.5f; // controls how quickly we approach the limit
float excessZoom = minZoomFactor - newZoomFactor;
excessZoom = 1.0f - (float) Math.exp(-excessZoom * rate);
newZoomFactor = minZoomFactor * (1.0f - excessZoom / 2.0f);
}
if (newZoomFactor > maxZoomFactor) {
// apply resistance when zooming past maxZoomFactor,
// such that it asymptotically reaches maxZoomFactor + 1.0
// but never exceeds that
float excessZoom = newZoomFactor - maxZoomFactor;
excessZoom = 1.0f - (float) Math.exp(-excessZoom);
newZoomFactor = maxZoomFactor + excessZoom;
}
scrollBy(mLastZoomFocus.x - detector.getFocusX(), mLastZoomFocus.y - detector.getFocusY());
PointF focus = new PointF(detector.getFocusX(), detector.getFocusY());
scaleWithFocus(newZoomFactor, focus);
}
mLastZoomFocus.set(detector.getFocusX(), detector.getFocusY());
GeckoEvent event =
GeckoEvent.createNativeGestureEvent(
GeckoEvent.ACTION_MAGNIFY, mLastZoomFocus, getMetrics().zoomFactor);
GeckoAppShell.sendEventToGecko(event);
return true;
}
private ImmutableViewportMetrics getMetrics() {
return mTarget.getViewportMetrics();
}
private void scrollBy(float dx, float dy) {
ImmutableViewportMetrics scrolled = getMetrics().offsetViewportBy(dx, dy);
mTarget.setViewportMetrics(scrolled);
}
