当我放大屏幕时，我遇到了uipangesturerecognizer的问题。
我的应用程序有一个带uiview的uiviewcontroller。
在这个视图中，我有一个几乎占整个屏幕边界一半的calayer。
这个calayer有几个子图层，用户可以拖动（uipangesture），添加（uitapgesture）和删除（doubletapgesture）。为了更准确地拖动，我添加了一个uipinchgesture方法来放大和缩小。
此时一切正常，除非我放大并尝试移动（pangesture）子层。有时工作但通常不工作（没有放大总能正常工作）。
我不知道我的代码中是否有问题，或者可能不是这样做的。有什么我想念的吗？
我在sdk 4.2下。
这些是我的代码：
- (id)initWithFrame:(CGRect)frame
{
[super initWithFrame:frame];
(…)
perfil = [[CALayer alloc] init]; //the calayer of the uiview
[perfil setBounds:CGRectMake(0, 0, wide, heigth/2)];
[[self layer] addSublayer:perfil];
//I add the sublayers to the "peril" layer when the user touch an "edit button" and that works fine
//UIGsture Recognizers
UITapGestureRecognizer *singleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTapFrom:)];
UITapGestureRecognizer *doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleDoubleTapFrom:)];
UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinchFrom:)];
UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanFrom:)];
[panGestureRecognizer setMinimumNumberOfTouches:1];
[panGestureRecognizer setMaximumNumberOfTouches:1];
[singleTapRecognizer setNumberOfTapsRequired:1];
[singleTapRecognizer setCancelsTouchesInView:NO];
[doubleTapRecognizer setNumberOfTapsRequired:2];
[self addGestureRecognizer:singleTapRecognizer];
[self addGestureRecognizer:doubleTapRecognizer];
[self addGestureRecognizer:pinchGestureRecognizer];
[self addGestureRecognizer:panGestureRecognizer];
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
singleTapRecognizer.delegate = self;
doubleTapRecognizer.delegate = self;
pinchGestureRecognizer.delegate = self;
panGestureRecognizer.delegate = self;
//Some other different stuff here
}
- (void) handlePanFrom: (id)sender
{
CGPoint point = [(UIPanGestureRecognizer*)sender locationInView:self];
boxLayer = [[self perfil] hitTest:point];
[self becomeFirstResponder];
if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan)
{
numberOfSublayer = 1000; //declared as a int in UIView.h
for (CALayer *elements in [perfil sublayers])
{
if([boxLayer isEqual:elements])
{
numberOfSublayer = [[perfil sublayers] indexOfObject:elements];
break;
}
}
}
(…) //Some more operations once I found the sublayer
}
- (void) handlePinchFrom: (id)sender
{
if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded)
{
lastScale = 1.0;
return;
}
if ([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan ||
[(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateChanged) {
CGFloat currentScale = [[[sender view].layer valueForKeyPath:@"transform.scale"] floatValue];
const CGFloat kMaxScale = 4.0;
const CGFloat kMinScale = 1.0;
CGFloat newScale = 1 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]);
newScale = MIN(newScale, kMaxScale / currentScale);
newScale = MAX(newScale, kMinScale / currentScale);
CGAffineTransform transform = CGAffineTransformScale([[sender view] transform], newScale, newScale);
[sender view].transform = transform;
if ([perfil sublayers])
{
for (CALayer *elements in [perfil sublayers]) //Here I try to adjust the zoom to the sublayers
{
//Here is one first approach
//CGAffineTransform transformELS = CGAffineTransformScale([elements affineTransform], 7/(newScale+6), 7/(newScale+6));
//[elements setAffineTransform:transformELS];
//Here is a second approach
[elements setBounds:CGRectMake(0, 0, elements.bounds.size.width*7/(newScale+6), elements.bounds.size.height*7/(newScale+6))];
}
}
lastScale = [(UIPinchGestureRecognizer*)sender scale];
(…) //Some other different stuff here
}
非常感谢。
答案 0 :(得分：1)
最后我找到了问题的答案。这篇文章解释了完全相同的问题，它的解决方案对我来说非常有用 UIPanGestureRecognizer starting point is off。感谢。
答案 1 :(得分：0)
如果没有看到sublayer hittest代码真的很难说，但是在重新缩放父视图/图层时重新缩放子图层似乎很奇怪。
您只需要缩放父图层，所有子项将依次缩放。
所有这些手动生成的夹紧和平移代码都充满了危险。它可以做到，但我发现你最终得意大利面。
将您的视图放在UIScrollView中，让它完成perfil视图的压缩和平移工作。
这是UIScrollView平移和缩放的十亿个例子。如果您还没有，Google和SO会知道。
我希望在父视图的touchBegan事件中捕获子图层的平移。
这是我用来捕捉子层中的命中
- (CALayer *)hitTest:(CGPoint)thepoint
{
//
CGPoint cpoint = [self convertPoint:thepoint fromLayer:self.superlayer];
if (CGRectContainsPoint([self bounds], cpoint)) {
NSLog(@"hitme!");
return self;
}
return nil;
}
这是在父视图的touchesBegan / touchesMoved中。 （保持对滚动视图的弱引用）
// Handles the start of a touch
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSUInteger tcount = [touches count];
if(tcount == 1)
{
UITouch* touch = [touches anyObject];
CGPoint tpoint = [touch locationInView:self];
location = [perfil convertPoint:tpoint fromLayer:view.layer];
hitsublayer = [self hitTest:location];
if([hitsublayer isKindOfClass:[MySubBoxThing class]]){
//ensure that scroll view doesn't capture the event
scrollview.canCancelContentTouches = NO;
}
else {
hitsublayer = nil;
//or something else to do wit not touching a sublayer.
}
}
// Handles the continuation of a touch.
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSUInteger tcount = [touches count];
if (tcount == 1 && hitsublayer) {
UITouch* touch = [touches anyObject];
CGPoint tlocation = [touch locationInView:self];
location = [perfil convertPoint:tpoint fromLayer:view.layer];
NSLog(@"new loc = %@",[NSValue valueWithCGPoint:location]);
hitsublayer.position = location;
}
}
// Handles the end of a touch event when the touch is a tap.
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
//NSLog(@"touches ended");
scrollview.canCancelContentTouches = YES;
hitsublayer = nil;
//any other actions once finished drag of object
}
该代码既不完整也不检查bug，但应该让你接近。