コード例 #1
0
 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);
     }
   }
 }
コード例 #2
0
  @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;
  }