public Transition GenerateNextTransition(RectF drawableBounds, RectF viewport)
{
bool firstTransition = _mLastGenTrans == null;
bool drawableBoundsChanged = true;
bool viewportRatioChanged = true;
RectF srcRect = null;
RectF dstRect = null;
if (!firstTransition)
{
dstRect = _mLastGenTrans.GetDestinyRect();
drawableBoundsChanged = !drawableBounds.Equals(_mLastDrawableBounds);
viewportRatioChanged = !MathUtils.HaveSameAspectRatio(dstRect, viewport);
}
if (dstRect == null || drawableBoundsChanged || viewportRatioChanged)
{
srcRect = GenerateRandomRect(drawableBounds, viewport);
}
else
{
/* Sets the destiny rect of the last transition as the source one
if the current drawable has the same dimensions as the one of
the last transition. */
srcRect = dstRect;
}
dstRect = GenerateRandomRect(drawableBounds, viewport);
_mLastGenTrans = new Transition(srcRect, dstRect, _mTransitionDuration,
_mTransitionIInterpolator);
_mLastDrawableBounds = drawableBounds;
return _mLastGenTrans;
}
/**
* Fires an end event on {@link #mTransitionListener};
* @param transition the transition that just ended.
*/
private void FireTransitionEnd(Transition transition)
{
if (_mTransitionListener != null && transition != null)
{
_mTransitionListener.OnTransitionEnd(transition);
}
}
/**
* Generates and starts a transition.
*/
private void StartNewTransition()
{
if (!HasBounds())
{
return; // Can't start transition if the drawable has no bounds.
}
_mCurrentTrans = _mTransGen.GenerateNextTransition(_mDrawableRect, _mViewportRect);
_mElapsedTime = 0;
_mLastFrameTime = JavaSystem.CurrentTimeMillis();
FireTransitionStart(_mCurrentTrans);
}