苹果iOS实例编程入门教程.docx

1、苹果iOS实例编程入门教程苹果iOS实例编程入门教程想给你的iPhone制作一场雪景吗?今天小编为大家整理了苹果iOS实例编程入门教程，一起来看看吧!纲要：- 在程序显示前运行代码 - UIImageView 的运用 - 关于iPhone的“Utility Application” 运用 - onTimer 代码运用 - onAnimation 代码运用 -首先运行以安装好的 xCode选择: File->New Project.从 "New Project" 窗口选择 : iPhone OS ->Applications-> Ut

2、ility Application命名 : 我这里命名为 “SnowFall”(1)  在xCode打开 MainView.h 文件,加入下面代码#importinterface MainViewController : UIViewController UIImage* flakeImage;property (nonatomic, retain) UIImage* flakeImage;- (void)onTimer;- (void)onAnimationComplete:(NSString *)animationID finished:(NSN

3、umber *)finished context:(void *)context;end(2)  在xCode打开 MainView.m 文件,加入下面代码#import "MainViewController.h"#import "MainView.h"implementation MainViewControllersynthesize flakeImage;- (void)viewDidLoad super viewDidLoad;/ 把背景颜色设置为冷色self.view.backgroundColor = UIColor c

4、olorWithRed:0.5 green:0.5 blue:1.0 alpha:1.0;/ 把雪花图片文件不停导出flakeImage = UIImage imageNamed:"flake.png"/ 在onTimer设置开始时间每秒二十次NSTimer scheduledTimerWithTimeInterval:(0.05) target:self selector:selector(onTimer) userInfo:nil repeats:YES;/ Timer event is called whenever the timer fires- (void)on

5、Timer/建立一个雪花图片 flake imageUIImageView* flakeView = UIImageView alloc initWithImage:flakeImage;/use the random() function to randomize up our flake attributesint startX = round(random() % 320);int endX = round(random() % 320);double scale = 1 / round(random() % 100) + 1.0;double speed = 1 / round(ran

6、dom() % 100) + 1.0;/ set the flake start positionflakeView.frame = CGRectMake(startX, -100.0, 25.0 * scale, 25.0 * scale);flakeView.alpha = 0.25;/ put the flake in our main viewself.view addSubview:flakeView;UIView beginAnimations:nil context:flakeView;/ set up how fast the flake will fallUIView set

7、AnimationDuration:5 * speed;/ set the postion where flake will move toflakeView.frame = CGRectMake(endX, 500.0, 25.0 * scale, 25.0 * scale);/ set a stop callback so we can cleanup the flake when it reaches the/ end of its animationUIView setAnimationDidStopSelector:selector(onAnimationComplete:finis

8、hed:context:);UIView setAnimationDelegate:self;UIView commitAnimations;- (void)onAnimationComplete:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context flakeView = nil;flakeView removeFromSuperview;/ open the debug log and you will see that all flakes have a retain count/ of

9、 1 at this point so we know the release below will keep our memory/ usage in checkNSLog(NSString stringWithFormat:"flakeView retainCount = %d", flakeView retainCount);flakeView release;- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation / Return YES

10、for supported orientationsreturn (interfaceOrientation = UIInterfaceOrientationPortrait);- (void)didReceiveMemoryWarning super didReceiveMemoryWarning; / Releases the view if it doesnt have a superview/ Release anything thats not essential, such as cached data- (void)dealloc flakeImage release;super dealloc;end(3) 导入下面图片文件下载下面图片，放入 SnowFall 文件夹内并命名为下面名称flake.png在xCode下右键点击 SnowFall->Add->Existing Files; 在 SnowFall 文件夹内，选择下载好的图片，按 Add，最后在 xCode 选择 Build->Build and Go; Save All.以上就是小编为大家整理的苹果iOS实例编程入门教程，希望对大家有所帮助。