如何在iphone中实现图片的放大（不使用多点触控：即两个手指拉开）

[静水-流深]

现在想在iphone中实现iphone的图片放大功能，将一张小图片放大到手机全屏这样一个动画效果，我想用calayer来实现，可是对它不太熟，请熟悉的朋友帮帮忙。很急。多谢了。

[云瑀]

请参照代码

#import <UIKit/UIKit.h>

#define IMAGE_VIEW_1	100
#define	IMAGE_VIEW_2	101

#define BIGRECT CGRectMake(0.0f, 0.0f, 320.0f, 435.0f)
#define SMALLRECT CGRectMake(130.0f, 187.0f, 60.0f, 60.0f) 

@interface ToggleView: UIView
{
	BOOL isOne;
}
@end

@implementation ToggleView

- (id) initWithFrame: (CGRect) aFrame;
{
	self = [super initWithFrame:aFrame];
	
	// Load both views, make them non-interactive
	UIImageView *imgView1 = [[UIImageView alloc] initWithFrame:BIGRECT];
	imgView1.image = [UIImage imageNamed:@"one.png"];
	imgView1.userInteractionEnabled = NO;
	imgView1.tag = IMAGE_VIEW_1;

	UIImageView *imgView2 = [[UIImageView alloc] initWithFrame:SMALLRECT];
	imgView2.image = [UIImage imageNamed:@"two.png"];
	imgView2.userInteractionEnabled = NO;
	imgView2.tag = IMAGE_VIEW_2;
	
	// image 1 is in front of image 2 to begin
	[self addSubview:imgView2];	
	[self addSubview:imgView1]; 
	isOne = YES;
	
	[imgView1 release];
	[imgView2 release];

	return self;
}

- (void) touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
	// Determine which view occupies which role
	UIImageView *big = (UIImageView *)[self viewWithTag: (isOne ? IMAGE_VIEW_1 : IMAGE_VIEW_2)];
	UIImageView *little = (UIImageView *)[self viewWithTag: (isOne ? IMAGE_VIEW_2 : IMAGE_VIEW_1)];
	isOne = !isOne;
	
	// Pack all the changes into the animation block
	CGContextRef context = UIGraphicsGetCurrentContext();
	[UIView beginAnimations:nil context:context];
	[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
	[UIView setAnimationDuration:1.0];

	[big setFrame:SMALLRECT];
	[big setAlpha:0.5];
	[little setFrame:BIGRECT];
	[little setAlpha:1.0];
	
	[UIView commitAnimations];
	
	// Hide the shrunken "big" image.
	[big setAlpha:0.0f];
	[[big superview] bringSubviewToFront:big];
}
@end

@interface HelloController : UIViewController
@end

@implementation HelloController
- (void)loadView
{
	ToggleView *contentView = [[ToggleView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
	contentView.backgroundColor = [UIColor whiteColor];
	self.view = contentView;
    [contentView release];
}
@end


@interface SampleAppDelegate : NSObject <UIApplicationDelegate> 
@end

@implementation SampleAppDelegate
- (void)applicationDidFinishLaunching:(UIApplication *)application {	
	UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
	HelloController *hello = [[HelloController alloc] init];
	[window addSubview:hello.view];
	[window makeKeyAndVisible];
}
@end

int main(int argc, char *argv[])
{
	NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	int retVal = UIApplicationMain(argc, argv, nil, @"SampleAppDelegate");
	[pool release];
	return retVal;
}

[云瑀]

http://blog.csdn.net/cloudhsu/archive/2010/08/26/5841089.aspx
该范例相关资料可到我的博客参考

[静水-流深]

谢谢帮忙了，我研究一下你的代码。

[静水-流深]

我已经实现了，还可以。谢谢了啊