ios开发基础知识 － 1

输出

command＋shift＋r

NSLog(@"log: %@ ", myString); 
NSLog(@"log: %f ", myFloat); 
NSLog(@"log: %i ", myInt);

显示图片

CGRect myImageRect = CGRectMake(0.0f, 0.0f, 320.0f, 100.0f); 
UIImageView *myImage = [[UIImageView alloc] initWithFrame:myImageRect]; 
[myImage setImage:[UIImage imageNamed:@"myImage.png"]]; 
[self.view addSubview:myImage]; 
[myImage release];

app frame 大小

CGRect bounds = [[UIScreen mainScreen] bounds];
CGRect frame = [UIScreen mainScreen].applicationFrame;

浏览器控件

CGRect webFrame = CGRectMake(0.0, 0.0, 320.0, 480.0);
UIWebView *webView = [[UIWebView alloc] initWithFrame:webFrame];
[webView setBackgroundColor:[UIColor clearColor]];
NSString *urlAddress = @"http://nasa.cnblogs.com";
NSURL *url = [NSURL URLWithString:urlAddress];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
[webView loadRequest:requestObj];
[self addSubview:webView];
[webView release];

在状态栏显示网络状态

UIApplication* app = [UIApplication sharedApplication];
app.networkActivityIndicatorVisible = YES; 

播放序列动画

NSArray *myImages = [NSArray arrayWithObjects:
[UIImage imageNamed:@"myImage1.png"],
[UIImage imageNamed:@"myImage2.png"],
[UIImage imageNamed:@"myImage3.png"],
[UIImage imageNamed:@"myImage4.gif"],
nil];
UIImageView *myAnimatedView = [UIImageView alloc];
[myAnimatedView initWithFrame:[self bounds]];
myAnimatedView.animationImages = myImages;
myAnimatedView.animationDuration = 0.25; // 秒
myAnimatedView.animationRepeatCount = 0; // 0 = 无限
[myAnimatedView startAnimating];
[self addSubview:myAnimatedView];
[myAnimatedView release];

提示筐

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil message:@"Alert!"          
delegate:self cancelButtonTitle:@"OK" 
otherButtonTitles:nil];
[alert show];
[alert release];