一,效果图。
二,工程图。
三,代码.
ViewController.h
#import <UIKit/UIKit.h> @interface ViewController : UIViewController @end
ViewController.m

#import "ViewController.h" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib. //UIView
UIView *view=[[UIView alloc]initWithFrame:CGRectMake(10, 100, 200, 200)];
view.backgroundColor=[UIColor redColor];
[self.view addSubview:view]; //淡出
//[self fadeOut:view]; //淡入
//[self fadeIn:view]; } //淡出
-(void) fadeOut:(UIView *)view
{
CGContextRef context = UIGraphicsGetCurrentContext();
[UIView beginAnimations:nil context:context];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0.3];
[view setAlpha:0.0f];
[UIView commitAnimations];
} //淡入
-(void) fadeIn:(UIView *)view
{
CGContextRef context = UIGraphicsGetCurrentContext();
[UIView beginAnimations:nil context:context];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationDuration:0.3];
[view setAlpha:1.0f];
[UIView commitAnimations];
} - (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
