实现iPhone漂亮的动画效果主要有两种方法,


   一种是UIView层面的,


  一种是使用CATransition进行更低层次的控制,


 


      第一种是UIView,UIView方式可能在低层也是使用CATransition进行了封装,它只能用于一些简单的、常用的效果展现,这里写一个常用的示例代码,供大家参考。


 


Cpp代码 


 [UIView beginAnimations:@"Curl"context:nil];//动画开始   


 [UIView setAnimationDuration:0.75];   


 [UIView setAnimationDelegate:self];  


 [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:myview cache:YES];   


[myview removeFromSuperview];   


[UIView commitAnimations];  


 


 


       第二种方式相对复杂一些,但如果更好的进行控制,还是使用这种方法吧,


基本使用方法可以看一下如下例子:


 


Cpp代码 


CATransition *animation = [CATransition animation];  


[animation setDuration:1.25f];   


[animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]];   


[animation setType:kCATransitionReveal];  


[animation setSubtype: kCATransitionFromBottom];  


[self.view.layer addAnimation:animation forKey:@"Reveal"];  


 


这里使用了setType与setSubtype组合,这使用个比较保险,因为他的参数就是官方API里定义的,他们的参数说明可以参考如下:


 


[animation setType:@"suckEffect"];


这里的suckEffect就是效果名称,可以用的效果主要有:


Cpp代码 


pageCurl 向上翻一页   


  


pageUnCurl 向下翻一页   


  


rippleEffect 滴水效果   


  


suckEffect 收缩效果,如一块布被抽走   


  


cube 立方体效果   


  


oglFlip 上下翻转效果   


 I have been using the latter for a lot of nice lightweight animations. You can use it crossfade two views, or fade one in in front of another, or fade it out. You can shoot a view over another like a banner, you can make a view stretch or shrink... I'm getting a lot of mileage out of beginAnimation/commitAnimations.


Don't think that all you can do is:


[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:myview cache:YES];


Here is a sample:


[UIView beginAnimations:nil context:NULL]; {


    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];


    [UIView setAnimationDuration:1.0];


        [UIView setAnimationDelegate:self];


        if (movingViewIn) {


// after the animation is over, call afterAnimationProceedWithGame


//  to start the game


                [UIView setAnimationDidStopSelector:@selector(afterAnimationProceedWithGame)];


//              [UIView setAnimationRepeatCount:5.0]; // don't forget you can repeat an animation


//              [UIView setAnimationDelay:0.50];


//              [UIView setAnimationRepeatAutoreverses:YES];


                gameView.alpha = 1.0;


                topGameView.alpha = 1.0;


                viewrect1.origin.y = selfrect.size.height - (viewrect1.size.height);


                viewrect2.origin.y = -20;


                topGameView.alpha = 1.0;


        }


        else {


        // call putBackStatusBar after animation to restore the state after this animation


                [UIView setAnimationDidStopSelector:@selector(putBackStatusBar)];


                gameView.alpha = 0.0;


                topGameView.alpha = 0.0;


        }


        [gameView setFrame:viewrect1];


        [topGameView setFrame:viewrect2];


} [UIView commitAnimations];


As you can see, you can play with alpha, frames, and even sizes of a view. Play around. You may be surprised with its capabilities.


 


 ==================


Dashed & solid line when using CGContext drawing


To get dashed line:


CGContextRef context = UIGraphicsGetCurrentContext();


float dash[2]={6 ,5}; // pattern 6 times “solid”, 5 times “empty”


CGContextSetLineDash(context,0,dash,2);


To get back to solid line:


float normal[1]={1};


CGContextSetLineDash(context,0,normal,0);