private void setContext(android.view.MotionEvent curr)
{
if (mCurrEvent != null)
{
mCurrEvent.recycle();
}
mCurrEvent = android.view.MotionEvent.obtain(curr);
mCurrLen = -1;
mPrevLen = -1;
mScaleFactor = -1;
android.view.MotionEvent prev = mPrevEvent;
int prevIndex0 = prev.findPointerIndex(mActiveId0);
int prevIndex1 = prev.findPointerIndex(mActiveId1);
int currIndex0 = curr.findPointerIndex(mActiveId0);
int currIndex1 = curr.findPointerIndex(mActiveId1);
if (prevIndex0 < 0 || prevIndex1 < 0 || currIndex0 < 0 || currIndex1 < 0)
{
mInvalidGesture = true;
android.util.Log.e(TAG, "Invalid MotionEvent stream detected.", new System.Exception
());
if (mGestureInProgress)
{
mListener.onScaleEnd(this);
}
return;
}
float px0 = prev.getX(prevIndex0);
float py0 = prev.getY(prevIndex0);
float px1 = prev.getX(prevIndex1);
float py1 = prev.getY(prevIndex1);
float cx0 = curr.getX(currIndex0);
float cy0 = curr.getY(currIndex0);
float cx1 = curr.getX(currIndex1);
float cy1 = curr.getY(currIndex1);
float pvx = px1 - px0;
float pvy = py1 - py0;
float cvx = cx1 - cx0;
float cvy = cy1 - cy0;
mPrevFingerDiffX = pvx;
mPrevFingerDiffY = pvy;
mCurrFingerDiffX = cvx;
mCurrFingerDiffY = cvy;
mFocusX = cx0 + cvx * 0.5f;
mFocusY = cy0 + cvy * 0.5f;
mTimeDelta = curr.getEventTime() - prev.getEventTime();
mCurrPressure = curr.getPressure(currIndex0) + curr.getPressure(currIndex1);
mPrevPressure = prev.getPressure(prevIndex0) + prev.getPressure(prevIndex1);
}
private int findNewActiveIndex(android.view.MotionEvent ev, int otherActiveId, int
oldIndex)
{
int pointerCount = ev.getPointerCount();
// It's ok if this isn't found and returns -1, it simply won't match.
int otherActiveIndex = ev.findPointerIndex(otherActiveId);
int newActiveIndex = -1;
{
// Pick a new id and update tracking state. Only pick pointers not on the slop edges.
for (int i = 0; i < pointerCount; i++)
{
if (i != oldIndex && i != otherActiveIndex)
{
float edgeSlop = mEdgeSlop;
float rightSlop = mRightSlopEdge;
float bottomSlop = mBottomSlopEdge;
float x = getRawX(ev, i);
float y = getRawY(ev, i);
if (x >= edgeSlop && y >= edgeSlop && x <= rightSlop && y <= bottomSlop)
{
newActiveIndex = i;
break;
}
}
}
}
return(newActiveIndex);
}
public virtual bool onTouchEvent(android.view.MotionEvent @event)
{
if (mInputEventConsistencyVerifier != null)
{
mInputEventConsistencyVerifier.onTouchEvent(@event, 0);
}
int action = @event.getActionMasked();
if (action == android.view.MotionEvent.ACTION_DOWN)
{
reset();
}
// Start fresh
bool handled = true;
if (mInvalidGesture)
{
handled = false;
}
else
{
if (!mGestureInProgress)
{
switch (action)
{
case android.view.MotionEvent.ACTION_DOWN:
{
mActiveId0 = @event.getPointerId(0);
mActive0MostRecent = true;
break;
}
case android.view.MotionEvent.ACTION_UP:
{
reset();
break;
}
case android.view.MotionEvent.ACTION_POINTER_DOWN:
{
// We have a new multi-finger gesture
// as orientation can change, query the metrics in touch down
android.util.DisplayMetrics metrics = mContext.getResources().getDisplayMetrics();
mRightSlopEdge = metrics.widthPixels - mEdgeSlop;
mBottomSlopEdge = metrics.heightPixels - mEdgeSlop;
if (mPrevEvent != null)
{
mPrevEvent.recycle();
}
mPrevEvent = android.view.MotionEvent.obtain(@event);
mTimeDelta = 0;
int index1 = @event.getActionIndex();
int index0 = @event.findPointerIndex(mActiveId0);
mActiveId1 = @event.getPointerId(index1);
if (index0 < 0 || index0 == index1)
{
// Probably someone sending us a broken event stream.
index0 = findNewActiveIndex(@event, index0 == index1 ? -1 : mActiveId1, index0);
mActiveId0 = @event.getPointerId(index0);
}
mActive0MostRecent = false;
setContext(@event);
// Check if we have a sloppy gesture. If so, delay
// the beginning of the gesture until we're sure that's
// what the user wanted. Sloppy gestures can happen if the
// edge of the user's hand is touching the screen, for example.
float edgeSlop = mEdgeSlop;
float rightSlop = mRightSlopEdge;
float bottomSlop = mBottomSlopEdge;
float x0 = getRawX(@event, index0);
float y0 = getRawY(@event, index0);
float x1 = getRawX(@event, index1);
float y1 = getRawY(@event, index1);
bool p0sloppy = x0 <edgeSlop || y0 <edgeSlop || x0> rightSlop || y0> bottomSlop;
bool p1sloppy = x1 <edgeSlop || y1 <edgeSlop || x1> rightSlop || y1> bottomSlop;
if (p0sloppy && p1sloppy)
{
mFocusX = -1;
mFocusY = -1;
mSloppyGesture = true;
}
else
{
if (p0sloppy)
{
mFocusX = @event.getX(index1);
mFocusY = @event.getY(index1);
mSloppyGesture = true;
}
else
{
if (p1sloppy)
{
mFocusX = @event.getX(index0);
mFocusY = @event.getY(index0);
mSloppyGesture = true;
}
else
{
mSloppyGesture = false;
mGestureInProgress = mListener.onScaleBegin(this);
}
}
}
break;
}
case android.view.MotionEvent.ACTION_MOVE:
{
if (mSloppyGesture)
{
// Initiate sloppy gestures if we've moved outside of the slop area.
float edgeSlop = mEdgeSlop;
float rightSlop = mRightSlopEdge;
float bottomSlop = mBottomSlopEdge;
int index0 = @event.findPointerIndex(mActiveId0);
int index1 = @event.findPointerIndex(mActiveId1);
float x0 = getRawX(@event, index0);
float y0 = getRawY(@event, index0);
float x1 = getRawX(@event, index1);
float y1 = getRawY(@event, index1);
bool p0sloppy = x0 <edgeSlop || y0 <edgeSlop || x0> rightSlop || y0> bottomSlop;
bool p1sloppy = x1 <edgeSlop || y1 <edgeSlop || x1> rightSlop || y1> bottomSlop;
if (p0sloppy)
{
// Do we have a different pointer that isn't sloppy?
int index = findNewActiveIndex(@event, mActiveId1, index0);
if (index >= 0)
{
index0 = index;
mActiveId0 = @event.getPointerId(index);
x0 = getRawX(@event, index);
y0 = getRawY(@event, index);
p0sloppy = false;
}
}
if (p1sloppy)
{
// Do we have a different pointer that isn't sloppy?
int index = findNewActiveIndex(@event, mActiveId0, index1);
if (index >= 0)
{
index1 = index;
mActiveId1 = @event.getPointerId(index);
x1 = getRawX(@event, index);
y1 = getRawY(@event, index);
p1sloppy = false;
}
}
if (p0sloppy && p1sloppy)
{
mFocusX = -1;
mFocusY = -1;
}
else
{
if (p0sloppy)
{
mFocusX = @event.getX(index1);
mFocusY = @event.getY(index1);
}
else
{
if (p1sloppy)
{
mFocusX = @event.getX(index0);
mFocusY = @event.getY(index0);
}
else
{
mSloppyGesture = false;
mGestureInProgress = mListener.onScaleBegin(this);
}
}
}
}
break;
}
case android.view.MotionEvent.ACTION_POINTER_UP:
{
if (mSloppyGesture)
{
int pointerCount = @event.getPointerCount();
int actionIndex = @event.getActionIndex();
int actionId = @event.getPointerId(actionIndex);
if (pointerCount > 2)
{
if (actionId == mActiveId0)
{
int newIndex = findNewActiveIndex(@event, mActiveId1, actionIndex);
if (newIndex >= 0)
{
mActiveId0 = @event.getPointerId(newIndex);
}
}
else
{
if (actionId == mActiveId1)
{
int newIndex = findNewActiveIndex(@event, mActiveId0, actionIndex);
if (newIndex >= 0)
{
mActiveId1 = @event.getPointerId(newIndex);
}
}
}
}
else
{
// Set focus point to the remaining finger
int index = @event.findPointerIndex(actionId == mActiveId0 ? mActiveId1 : mActiveId0
);
if (index < 0)
{
mInvalidGesture = true;
android.util.Log.e(TAG, "Invalid MotionEvent stream detected.", new System.Exception
());
if (mGestureInProgress)
{
mListener.onScaleEnd(this);
}
return(false);
}
mActiveId0 = @event.getPointerId(index);
mActive0MostRecent = true;
mActiveId1 = -1;
mFocusX = @event.getX(index);
mFocusY = @event.getY(index);
}
}
break;
}
}
}
else
{
switch (action)
{
case android.view.MotionEvent.ACTION_POINTER_DOWN:
{
// Transform gesture in progress - attempt to handle it
// End the old gesture and begin a new one with the most recent two fingers.
mListener.onScaleEnd(this);
int oldActive0 = mActiveId0;
int oldActive1 = mActiveId1;
reset();
mPrevEvent = android.view.MotionEvent.obtain(@event);
mActiveId0 = mActive0MostRecent ? oldActive0 : oldActive1;
mActiveId1 = @event.getPointerId(@event.getActionIndex());
mActive0MostRecent = false;
int index0 = @event.findPointerIndex(mActiveId0);
if (index0 < 0 || mActiveId0 == mActiveId1)
{
// Probably someone sending us a broken event stream.
android.util.Log.e(TAG, "Got " + android.view.MotionEvent.actionToString(action)
+ " with bad state while a gesture was in progress. " + "Did you forget to pass an event to "
+ "ScaleGestureDetector#onTouchEvent?");
index0 = findNewActiveIndex(@event, mActiveId0 == mActiveId1 ? -1 : mActiveId1, index0
);
mActiveId0 = @event.getPointerId(index0);
}
setContext(@event);
mGestureInProgress = mListener.onScaleBegin(this);
break;
}
case android.view.MotionEvent.ACTION_POINTER_UP:
{
int pointerCount = @event.getPointerCount();
int actionIndex = @event.getActionIndex();
int actionId = @event.getPointerId(actionIndex);
bool gestureEnded = false;
if (pointerCount > 2)
{
if (actionId == mActiveId0)
{
int newIndex = findNewActiveIndex(@event, mActiveId1, actionIndex);
if (newIndex >= 0)
{
mListener.onScaleEnd(this);
mActiveId0 = @event.getPointerId(newIndex);
mActive0MostRecent = true;
mPrevEvent = android.view.MotionEvent.obtain(@event);
setContext(@event);
mGestureInProgress = mListener.onScaleBegin(this);
}
else
{
gestureEnded = true;
}
}
else
{
if (actionId == mActiveId1)
{
int newIndex = findNewActiveIndex(@event, mActiveId0, actionIndex);
if (newIndex >= 0)
{
mListener.onScaleEnd(this);
mActiveId1 = @event.getPointerId(newIndex);
mActive0MostRecent = false;
mPrevEvent = android.view.MotionEvent.obtain(@event);
setContext(@event);
mGestureInProgress = mListener.onScaleBegin(this);
}
else
{
gestureEnded = true;
}
}
}
mPrevEvent.recycle();
mPrevEvent = android.view.MotionEvent.obtain(@event);
setContext(@event);
}
else
{
gestureEnded = true;
}
if (gestureEnded)
{
// Gesture ended
setContext(@event);
// Set focus point to the remaining finger
int activeId = actionId == mActiveId0 ? mActiveId1 : mActiveId0;
int index = @event.findPointerIndex(activeId);
mFocusX = @event.getX(index);
mFocusY = @event.getY(index);
mListener.onScaleEnd(this);
reset();
mActiveId0 = activeId;
mActive0MostRecent = true;
}
break;
}
case android.view.MotionEvent.ACTION_CANCEL:
{
mListener.onScaleEnd(this);
reset();
break;
}
case android.view.MotionEvent.ACTION_UP:
{
reset();
break;
}
case android.view.MotionEvent.ACTION_MOVE:
{
setContext(@event);
// Only accept the event if our relative pressure is within
// a certain limit - this can help filter shaky data as a
// finger is lifted.
if (mCurrPressure / mPrevPressure > PRESSURE_THRESHOLD)
{
bool updatePrevious = mListener.onScale(this);
if (updatePrevious)
{
mPrevEvent.recycle();
mPrevEvent = android.view.MotionEvent.obtain(@event);
}
}
break;
}
}
}
}
if (!handled && mInputEventConsistencyVerifier != null)
{
mInputEventConsistencyVerifier.onUnhandledEvent(@event, 0);
}
return(handled);
}