iPhone开发【十三】动画效果之最简单的动画——动态加载图片

转载请注明出处，原文网址：http://blog.csdn.net/m_changgong/article/details/8213792作者：张燕广

从本篇开始不再详细介绍每一步操作，而只介绍一些关键操作及展示核心代码和代码解释。

实现的功能：1）演示一个简单的动画效果，动态加载图片。2）点击屏幕时重新加载动画。

关键词：Animation 动画 动态加载图片

1、新建视图控制器ImageViewController（不带xib），作为根视图控制器，ImageViewController.h如下：

 #import <UIKit/UIKit.h>

 @interface ImageViewController : UIViewController

 @property(strong,nonatomic)UIImageView *imageView;
 @property(strong,nonatomic)UIImage *desktop;
 -(void)loadImage;
 @end

ImageViewController.m如下：

 <span style="font-size:18px;">#import "ImageViewController.h"
 @implementation ImageViewController
 @synthesize imageView;
 @synthesize desktop;

 - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
 {
     self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
     if (self) {
         // Custom initialization
     }
     return self;
 }

 - (void)loadView
 {
     // If you create your views manually, you MUST override this method and use it to create your views.
     // If you use Interface Builder to create your views, then you must NOT override this method.
     NSLog(@"loadView");
     UIView *view = [[ UIView alloc] initWithFrame:[ UIScreen
                                                    mainScreen].applicationFrame] ;
     UIColor *bgColor = [UIColor colorWithRed:1 green:1 blue:1 alpha:1.0];
     [view setBackgroundColor:(bgColor)];
     self.view = view;
     desktop = [UIImage imageNamed:@"desktop.png"];

     [self performSelector:@selector(loadImage) withObject:nil afterDelay:0.1];
 }

 -(void)loadImage{
     if(imageView!=nil){
         [imageView removeFromSuperview];
     }
     //初始时，将imageView的宽度设置为0，这样就隐藏起来了
     imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 0, desktop.size.height)];
     [imageView setImage:desktop];

     [self.view addSubview:imageView];
     //设置动画效果
     CGContextRef context = UIGraphicsGetCurrentContext();
     //开始播放动画
     [UIView beginAnimations:nil context:context];
     [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
     //[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
     //[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
     //[UIView setAnimationCurve:UIViewAnimationCurveLinear];
     [UIView setAnimationDuration:1.5];
     //imageView最终的宽度为desktop.size.width
     [imageView setFrame:CGRectMake(0, 0, desktop.size.width, desktop.size.height)];
     [UIView commitAnimations];
 }

 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
     [self loadImage];
 }

 - (void)viewDidLoad
 {
     [super viewDidLoad];
     // Do any additional setup after loading the view, typically from a nib.
 }

 - (void)viewDidUnload
 {
     [super viewDidUnload];
     // Release any retained subviews of the main view.
     imageView = nil;
     desktop = nil;
 }

 - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
 {
     return (interfaceOrientation == UIInterfaceOrientationPortrait);
 }

 @end
 </span>

2、运行效果是图片从左至右慢慢显示出来，如下，