怎样实现UIView的旋转

首先创建界面，在viewDidLoad创建view以及button

相关代码如下

-(void)viewDidLoad

{

[super viewDidLoad];

viewDemo = [[UIView alloc] initWithFrame:CGRectMake(0, 50, 320, 50)];

[viewDemo setBackgroundColor:[UIColor brownColor]];

UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 100, 50)];

label.text =@"Test";

label.tag=100;

[viewDemo addSubview:label];

[self.view addSubview:viewDemo];

[label release];

// Do any additional setup after loading the view, typically from a nib.

UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(0, 400, 100, 50)];

[btn setBackgroundColor:[UIColor blueColor]];

btn.showsTouchWhenHighlighted = YES;

[btn setTitle:@"点击旋转" forState:UIControlStateNormal];

[self.view addSubview:btn];

btn.tag = 10010;

[btn addTarget:self action:@selector(testViewDemo) forControlEvents:UIControlEventTouchUpInside];

[btn release];

number = 0;

}

-(void)testViewDemo

{

number++;

if (number%3 == 0) {

CGAffineTransform at = CGAffineTransformMakeRotation(M_PI/2);

at = CGAffineTransformTranslate(at, 200, 0);

[viewDemo setTransform:at];

}else if (number%3 ==1 ){

CGAffineTransform at = CGAffineTransformMakeRotation(M_PI/1);

at = CGAffineTransformTranslate(at, 0, 0);

[viewDemo setTransform:at];

}else if(number%3 ==2){

CGAffineTransform at = CGAffineTransformMakeRotation(M_PI*2);

at = CGAffineTransformTranslate(at, 0, 0);

[viewDemo setTransform:at];

}

}

-(void)testViewDemo

{

//旋转,左旋

number++;

CGAffineTransform rotate = CGAffineTransformMakeRotation(number / 180.0 * M_PI );

[viewDemo setTransform:rotate];

}

如果使用此方法连续点击button就可以显示处一点一点的移动效果

每次旋转90度的话可以使用一下的代码实现效果

-(void)testViewDemo

{

//旋转,右旋

number = number+90.0;

CGAffineTransform rotate = CGAffineTransformMakeRotation(number / 180.0 * M_PI );

[viewDemo setTransform:rotate];

｝

UIView实现左旋效果

//旋转,左旋

number = number-90.0;

CGAffineTransform rotate = CGAffineTransformMakeRotation(number / 180.0 * M_PI );

[viewDemo setTransform:rotate];

通过以上的讲解，我想，关于点击UIButton实现UIView的旋转大家就可以轻松的操作了。

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