// Set frame callback to start drag animation.
private void SetFrameCallback(float position)
{
// remove frame callback if it is already added.
mWindow.RemoveFrameCallback(mFrameCallback);
mFrameCallback.ResetAnimationData();
mFrameCallback.AddMovement(0.0f); // Add first movement.
// Set container start position and start positions of each icon(and vertical bar)
// And compute total container size.
float totalSize = 0.0f;
mFrameCallback.SetContainerStartPosition(mControlView.Position.X);
for (int i = 0; i < mLayoutView.ChildCount; ++i)
{
mFrameCallback.SetViewPosition(i, mLayoutView.Children[i].Position.X);
totalSize += (float)(mLayoutView.Children[i].Size.Width + DEFAULT_SPACE);
}
totalSize -= (float)DEFAULT_SPACE;
// Find touched icon
for (int i = (int)mLayoutView.ChildCount - 1; i >= 0; --i)
{
if (position >= mLayoutView.Children[i].Position.X + mControlView.Position.X)
{
mFrameCallback.SetTouchedViewIndex(i);
mTouchedViewIndex = i;
break;
}
}
if (position < mLayoutView.Children[0].Position.X + mControlView.Position.X)
{
mFrameCallback.SetTouchedViewIndex(0);
mTouchedViewIndex = 0;
}
mPreviousTouchedPosition = position;
// Add frame callback on window.
// OnUpdate callback of mFrameCallback will be called before every render frame.
mWindow.AddFrameCallback(mFrameCallback);
// compute limit position the container could go.
mLeftDirectionLimit = (float)mWindow.Size.Width - (totalSize + (float)(INITIAL_POSITION));
mWindow.RenderingBehavior = RenderingBehaviorType.Continuously; // make rendering be done for upto 60 fps even though there is no update in main thread.
mAnimationState = TOUCH_ANIMATION_STATE.ON_ANIMATION; // make rendering state on.
}
