UIPinchGestureRecognizer problem
I am using UIPinchGestureRecognize开发者_JAVA技巧r.can i write two action for pinch in and pinch out..is there any specific Method(delegate)?I have written only one it is called when i pinched in...
UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinchGesture:)];
[self.view addGestureRecognizer:pinchGesture];
[pinchGesture release];
You could check the gesture's .scale
in -handlePinchGesture:
. If it is < 1, it is a pinch-in, otherwise is a pinch-out.
// Zoom the image by the current scale
[Export("ScaleImage")]
void ScaleImage (UIPinchGestureRecognizer gestureRecognizer)
{
AdjustAnchorPointForGestureRecognizer (gestureRecognizer);
if (gestureRecognizer.State == UIGestureRecognizerState.Began || gestureRecognizer.State == UIGestureRecognizerState.Changed)
{
gestureRecognizer.View.Transform *= CGAffineTransform.MakeScale (gestureRecognizer.Scale, gestureRecognizer.Scale);
// Reset the gesture recognizer's scale - the next callback will get a delta from the current scale.
gestureRecognizer.Scale = 1;
}
}
void AdjustAnchorPointForGestureRecognizer (UIGestureRecognizer gestureRecognizer)
{
if (gestureRecognizer.State == UIGestureRecognizerState.Began)
{
var image = gestureRecognizer.View;
var locationInView = gestureRecognizer.LocationInView (image);
var locationInSuperview = gestureRecognizer.LocationInView (image.Superview);
image.Layer.AnchorPoint = new PointF (locationInView.X / image.Bounds.Size.Width, locationInView.Y / image.Bounds.Size.Height);
image.Center = locationInSuperview;
}
}
// Zoom the image by the current scale
[Export("ScaleImage")]
void ScaleImage (UIPinchGestureRecognizer gestureRecognizer)
{
AdjustAnchorPointForGestureRecognizer (gestureRecognizer);
if (gestureRecognizer.State == UIGestureRecognizerState.Began || gestureRecognizer.State == UIGestureRecognizerState.Changed)
{
gestureRecognizer.View.Transform *= CGAffineTransform.MakeScale (gestureRecognizer.Scale, gestureRecognizer.Scale);
// Reset the gesture recognizer's scale - the next callback will get a delta from the current scale.
gestureRecognizer.Scale = 1;
}
}
精彩评论