我在iOS中有一张图片。当我捏住移动到左上角的图像时，我在图像上添加了捏合手势。我还在图像上添加了平移手势。当图像被缩放时，我在每个方向上滚动图像为此目的我已将平移手势添加到图像中。
我的代码是：
-(void)viewDidLoad
{
UIPinchGestureRecognizer *pinch=[[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(handlePinch:)];
[self.zoom_image addGestureRecognizer:pinch];
panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(moveImage:)];
[panGesture setMinimumNumberOfTouches:1];
[panGesture setMaximumNumberOfTouches:1];
[self.zoom_image addGestureRecognizer:panGesture];
img_center_x = self.zoom_image.center.x;
img_center_y = self.zoom_image.center.y;
}
-(void)handlePinch:(UIPinchGestureRecognizer*)sender
{
NSLog(@"latscale = %f",mLastScale);
mCurrentScale += [sender scale] - mLastScale;
mLastScale = [sender scale];
NSLog(@"before ceneter x %f",img_center_x);
NSLog(@"before ceneter x %f",img_center_y);
CGPoint img_center = CGPointMake(img_center_x, img_center_y);
self.zoom_image.center = img_center;
if (sender.state == UIGestureRecognizerStateEnded)
{
mLastScale = 1.0;
}
if(mCurrentScale<1.0)
{
mCurrentScale=1.0;
}
if(mCurrentScale>3.0)
{
mCurrentScale=3.0;
}
CGAffineTransform currentTransform = CGAffineTransformIdentity;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform,mCurrentScale, mCurrentScale);
self.zoom_image.transform = newTransform;
}
平移手势
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(moveImage:)];
[panGesture setMinimumNumberOfTouches:1];
[panGesture setMaximumNumberOfTouches:1];
[self.zoom_image addGestureRecognizer:panGesture];
move image:
- (void)moveImage:(UIPanGestureRecognizer *)recognizer
{
CGPoint translation = [recognizer translationInView:self.zoom_image];
CGPoint location = [recognizer locationInView:self.view];
CGPoint initial=CGPointZero;
NSLog(@"%f\n%f",translation.x,translation.y);
NSLog(@"%f",self.zoom_image.frame.origin.y);
CGPoint finalpoint = CGPointMake(self.zoom_image.center.x + translation.x, self.zoom_image.center.y+ translation.y);
NSLog(@"%f",finalpoint.y);
//limit the boundary
if(recognizer.state==UIGestureRecognizerStateChanged)
{
if ((self.zoom_image.frame.origin.x>0 && translation.x > 0) || (self.zoom_image.frame.origin.x + self.zoom_image.frame.size.width<=self.view.frame.size.width && translation.x < 0))
finalpoint.x = self.zoom_image.center.x;
if ((self.zoom_image.frame.origin.y>100 && translation.y > 0) || (self.zoom_image.frame.origin.y + self.zoom_image.frame.size.height<=self.view.frame.size.height && translation.y < 0))
finalpoint.y = self.zoom_image.center.y;
//set final position
NSLog(@"%f",finalpoint.y);
self.zoom_image.center = finalpoint;
[recognizer setTranslation:initial inView:self.zoom_image];
}
}
答案 0 :(得分：0)
这是一个可能的解决方案。
•我已经通过contentView重命名了你的zoom_image，因为这个类可以操作任何视图，而不仅仅是图像。
•我删除了绑定测试，并让比例为（0.01 - 10.0）
•捏手柄最多三个手指，也可作为平底锅使用。可以在不中断夹点的情况下更改触摸次数。
还有很多事情需要改进，但主要原则是：）
界面（minScale，maxScale，minMargin等属性仍然需要添加 - 为什么不是委托）
@interface PinchViewController : UIViewController
@property(nonatomic,strong) IBOutlet UIView* contentView;
@end
<强>实施
@implementation PinchViewController
{
CGPoint translation;
CGFloat scale;
CGAffineTransform scaleTransform;
CGAffineTransform translateTransform;
CGPoint previousTranslation;
CGFloat previousScale;
NSUInteger previousNumTouches;
}
-(void)viewDidLoad
{
scale = 1.0f;
scaleTransform = CGAffineTransformIdentity;
translateTransform = CGAffineTransformIdentity;
previousTranslation = CGPointZero;
previousNumTouches = 0;
UIPinchGestureRecognizer *pinch=[[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(handlePinch:)];
[self.view addGestureRecognizer:pinch];
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
[panGesture setMinimumNumberOfTouches:1];
[panGesture setMaximumNumberOfTouches:1];
[self.view addGestureRecognizer:panGesture];
}
-(void)handlePinch:(UIPinchGestureRecognizer*)recognizer
{
// 1 - find pinch center
CGPoint mid = [self computePinchCenter:recognizer];
mid.x-= recognizer.view.bounds.size.width / 2.0f;
mid.y-= recognizer.view.bounds.size.height / 2.0f;
// 2 - compute deltas
NSUInteger numTouches = recognizer.numberOfTouches;
if ( (recognizer.state==UIGestureRecognizerStateBegan) || ( previousNumTouches != numTouches ) ) {
previousScale = recognizer.scale;
previousTranslation = mid;
previousNumTouches = numTouches;
}
CGFloat deltaScale = ( recognizer.scale - previousScale ) * scale;
previousScale = recognizer.scale;
CGPoint deltaTranslation = CGPointMake(mid.x-previousTranslation.x, mid.y-previousTranslation.y);
previousTranslation = mid;
deltaTranslation.x/=scale;
deltaTranslation.y/=scale;
// 3 - apply
scale+=deltaScale;
if (scale<0.01) scale = 0.01; else if (scale>10) scale = 10;
scaleTransform = CGAffineTransformMakeScale(scale, scale);
[self translateBy:deltaTranslation];
NSLog(@"Translation : %.2f,%.2f - Scale Center : %.2f,%.2f - Scale : %.2f",deltaTranslation.x,deltaTranslation.y,mid.x,mid.y,scale);
}
- (void)handlePan:(UIPanGestureRecognizer *)recognizer
{
if (recognizer.state==UIGestureRecognizerStateBegan) previousTranslation = CGPointZero;
CGPoint recognizerTranslation = [recognizer translationInView:self.contentView];
CGPoint deltaTranslation = CGPointMake(recognizerTranslation.x - previousTranslation.x,recognizerTranslation.y - previousTranslation.y);
previousTranslation = recognizerTranslation;
[self translateBy:deltaTranslation];
NSLog(@"Translation : %.2f,%.2f - Scale : %.2f",deltaTranslation.x,deltaTranslation.y,scale);
}
-(void)translateBy:(CGPoint)delta
{
translation.x+=delta.x;
translation.y+=delta.y;
translateTransform = CGAffineTransformMakeTranslation(translation.x,translation.y);
self.contentView.transform = CGAffineTransformConcat(translateTransform,scaleTransform);
}
-(CGPoint)computePinchCenter:(UIPinchGestureRecognizer*)recognizer
{
// 1 - handle up to 3 touches
NSUInteger numTouches = recognizer.numberOfTouches;
if (numTouches>3) numTouches = 3;
// 2 - Find fingers middle point - with (0,0) being the center of the view
CGPoint pt1,pt2,pt3,mid;
switch (numTouches) {
case 3:
pt3 = [recognizer locationOfTouch:2 inView:recognizer.view];
case 2:
pt2 = [recognizer locationOfTouch:1 inView:recognizer.view];
case 1:
pt1 = [recognizer locationOfTouch:0 inView:recognizer.view];
}
switch (numTouches) {
case 3:
mid = CGPointMake( ( ( pt1.x + pt2.x ) / 2.0f + pt3.x ) / 2.0f, ( ( pt1.y + pt2.y ) / 2.0f + pt3.y ) / 2.0f );
break;
case 2:
mid = CGPointMake( ( pt1.x + pt2.x ) / 2.0f, ( pt1.y + pt2.y ) / 2.0f );
break;
case 1:
mid = CGPointMake( pt1.x, pt1.y);
break;
}
return mid;
}
@end
希望它会有所帮助:)干杯