我一直在试图使用CGAffinTransformScale(使用CGAffinTransformScale(计划使用旋转,因此不能指望框架的缩放和添加子视图,因此UIScrollView将实现捏缩放/进出更复杂,我认为)。无论如何,这个概念很容易掌握,并且代码很快就会聚集在一起......从那以后,我一直试图用三种不同的方法解决相同的两个(相关的!)问题,并且无法做到这一点: 1-我的代码以某种方式失去了在缩放中间触摸计数的轨迹,从count = 2到count = 1并返回到iPhone,但不是模拟器。 2-触摸点1和2在每次移动中都会来回跳动几个像素,从而导致图像依次快速缩小和放大,即使总体效果是缩小或缩放为用户所期望的效果( iPhone和模拟器)。iPhone UIImageView pinch zoom
下面的代码:
#import "PhotoView.h"
@implementation PhotoView;
@synthesize originalCenter, distance, zooming;
- (id)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]) {
// Initialization code
self.userInteractionEnabled = YES;
self.multipleTouchEnabled = YES;
zooming = NO;
}
return self;
}
float distanceBetweenTwoPoints(CGPoint point1, CGPoint point2)
{
NSLog(@"point1 x: %5.2f point 2 x: %5.2f ---- point 1 y: %5.2f point 2 y: %5.2f",point1.x,point2.x,point1.y,point2.y);
return (sqrt(pow(point1.x -point2.x,2) + pow(point1.y - point2.y,2)));
}
-(void) touchesBegan: (NSSet *) touches withEvent:(UIEvent *) event {
if ([touches count] > 1) {
NSLog(@"^^^^^^^^^^^^^^^Tocuhes began with double touch!");
distance = distanceBetweenTwoPoints([[[touches allObjects] objectAtIndex:0] locationInView:self],
[[[touches allObjects] objectAtIndex:1] locationInView:self]);
zooming = YES;
}
else {
zooming = NO;
origianlCenter = [[[touches allObjects] objectAtIndex:0] locationInView:self];
NSLog(@">>>>>>>>>>>>Touches began with single touch");
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if (zooming) NSLog(@"!!!!!!!!!end zoom!!!!!!!");
zooming = NO;
if ([[touches anyObject] tapCount] == 2) {
UITouch *thisTouch = [touches anyObject];
CGPoint thisPoint = [thisTouch locationInView:self];
}
}
- (void) touchesMoved: (NSSet *) touches withEvent:(UIEvent *) event {
if ([touches count] > 1 && zooming) { // ignore if user added a second finger touch
float distanceNew = distanceBetweenTwoPoints([[[touches allObjects] objectAtIndex:0] locationInView:self],
[[[touches allObjects] objectAtIndex:1] locationInView:self]);
if (distance <= 0.f) { // should never be true - but it is sometimes!!!
distance = distanceNew;
}
float delta = 1.0f + ((distanceNew-distance)/distance);
self.transform = CGAffineTransformScale(self.transform, delta, delta);
distance = distanceNew;
}
else {
if (zooming) {
NSLog(@"*************shouldn't be here********* %d",[touches count]);
return;
}
CGPoint thisPoint = [[[touches allObjects] objectAtIndex:0] locationInView:self];
self.transform = CGAffineTransformTranslate(self.transform, thisPoint.x-originalCenter.x, thisPoint.y-originalCenter.y);
}
}
- (void)dealloc {
[super dealloc];
}
@end
日志样本:
^^^^^^^^^^^^^^^Tocuhes began with double touch!
point1 x: 87.33 point 2 x: 235.63 ---- point 1 y: 322.30 point 2 y: 117.09
point1 x: 90.76 point 2 x: 232.02 ---- point 1 y: 318.29 point 2 y: 123.51
point1 x: 86.22 point 2 x: 236.71 ---- point 1 y: 323.30 point 2 y: 117.42
point1 x: 89.51 point 2 x: 232.38 ---- point 1 y: 319.47 point 2 y: 123.47
point1 x: 84.97 point 2 x: 237.02 ---- point 1 y: 324.48 point 2 y: 116.56
*************shouldn't be here********* 1
point1 x: 88.49 point 2 x: 232.52 ---- point 1 y: 321.27 point 2 y: 122.91
*************shouldn't be here********* 1
point1 x: 83.95 point 2 x: 237.11 ---- point 1 y: 327.21 point 2 y: 116.96
!!!!!!!!!end zoom!!!!!!!
我开始怀疑,我失去的轨道,因为CGAffinTransformScale的触摸点;然而,我还没有发现任何网上任何事情表明这是一个问题。任何线索(包括'阅读xyz文档'),将不胜感激!
在此先感谢。
就是这样!非常感谢你。 – cameron 2010-01-25 22:14:15