1、NSCalendar用法
-(NSString *) getWeek:(NSDate *)d
{
NSCalendar *calendar = [[NSCalendar alloc]
initWithCalendarIdentifier:NSGregorianCalendar];
unsigned units = NSYearCalendarUnit | NSMonthCalendarUnit |
NSDayCalendarUnit | NSWeekCalendarUnit;
NSDateComponents *components = [calendar components:units
fromDate:d];
[calendar release];
switch ([components weekday]) {
case1:
return @"Monday"; break;
case2:
return @"Tuesday"; break;
case3:
return @"Wednesday"; break;
case4:
return @"Thursday"; break;
case5:
return @"Friday"; break;
case6:
return @"Saturday"; break;
case7:
return @"Sunday"; break;
default:
return @"NO Week"; break;
}
NSLog(@"%@",components);
}
2、将网络数据读取为字符串
-(NSString *)getDataByURL:(NSString *)url {
return [[NSString alloc] initWithData:[NSDatadataWithContentsOfURL: [NSURL URLWithString:[urlstringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]]encoding:NSUTF8StringEncoding];
}
3、读取?络图?
-(UIImage *)getImageByURL:(NSString *)url {
return [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[urlstringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]]];
}
4、多线程(这种方式,只管建立线程,不管回收线程)
[NSThread detachNewThreadSelector:@selector(scheduleTask)toTarget:self withObject:nil];
-(void)scheduleTask
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
[pool release];
}
如果有参数,则这么?
[NSThread detachNewThreadSelector:@selector(scheduleTask:)toTarget:self withObject:[NSDate date]];
-(void)scheduleTask:(NSDate *)mdate
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
[pool release]; }
在线程?运?主线程?的?法
[self performSelectorOnMainThread:@selector(moveToMain)withObject:nil waitUntilDone:FALSE];
5、?户缺省值NSUserDefaults读取:
NSUserDefaults *df = [NSUserDefaults standardUserDefaults];
NSArray *languages = [df objectForKey:@"AppleLanguages"];
NSLog(@"all language is %@",languages);
NSLog(@"index is %@",[languages objectAtIndex:0]);
NSLocale *currentLocale = [NSLocale currentLocale];
NSLog(@"language Code is %@",[currentLocaleobjectForKey:NSLocaleLanguageCode]);
NSLog(@"Country Code is %@",[currentLocaleobjectForKey:NSLocaleCountryCode]);
6、view之间转换的动态效果设置
SecondViewController *secondViewController = [[SecondViewControlleralloc] init];
secondViewController.modalTransitionStyle =UIModalTransitionStyleFlipHorizontal;//?水平翻转
[self.navigationControllerpresentModalViewController:secondViewControlleranimated:YES];
[secondViewController release];
7、UIScrollView 滑动用法: -(void)scrollViewDidScroll:(UIScrollView*)scrollView
{
NSLog(@"正在滑动中。。")
}
//?户直接滑动UIScrollView,可以看到滑动条
-(void)scrollViewDidEndDelerating:(UIScrollView *)scrollView{
}
//通过其他控件触发UIScrollView滑动,看不到滑动条
-(void)scrollViewDidEndScrollingAnimation:(UIScrollView*)scrollView {
}
//UIScrollView 设置滑动不超出本?身范围
[scrollView setBounces:NO];
8、iphone的系统目录:
//得到Document:目录
NSArray *paths =
NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//得到temp临时目录
NSString *temPath = NSTemporaryDirectory();
//得到目录上的文件地址
NSString *address = [pathsstringByAppendingPathComponent:@"1.rtf"];
9、状态栏显?示indicator
[UIApplication sharedApplication].networkActivityIndicatorVisible =YES;
10、app Icon显示数字:
- (void)applicationDidEnterBackground:(UIApplication*)application
{
[[UIApplication sharedApplication]setApplicationIconBadgeNumber:5];
}
11、sqlite保存地址:
NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectoryNSUserDomainMask,YES);
NSString *thePath = [paths objectAtIndex:0];
NSString *filePath = [thePathstringByAppendingPathComponent:@"kilometer.sqlite"];
NSString *dbPath = [[[NSBundle mainBundle]resourcePathstringByAppendingPathComponent:@"kilometer2.sqlite"];
12、键盘弹出隐藏,textfield变位置
_tspasswordTF = [[UITextField alloc] initWithFrame:CGRectMake(100,
150, 260, 30)];
_tspasswordTF.backgroundColor = [UIColor redColor];
_tspasswordTF.tag = 2;
//添加边框
CALayer*layer = [self.pageContenter layer];
layer.borderColor= [[UIColorwhiteColor]CGColor];
layer.borderWidth=0.0f;
//添加四个边阴影
self.pageContenter.layer.shadowColor=[UIColorblackColor].CGColor;//阴影颜色
self.pageContenter.layer.shadowOffset=CGSizeMake(0,0);//阴影偏移self.pageContenter.layer.shadowOpacity=0.5;//阴影不透明度self.pageContenter.layer.shadowRadius=5.0;//阴影半径
二、给视图加上阴影
UIView * content=[[UIView alloc] initWithFrame:CGRectMake(100, 250,503, 500)];
content.backgroundColor=[UIColor orangeColor];
//content.layer.shadowOffset=10;
content.layer.shadowOffset = CGSizeMake(5, 3);content.layer.shadowOpacity = 0.6; content.layer.shadowColor =[UIColor blackColor].CGColor;
[self.window addSubview:content];
76、UIView有一个属性,clipsTobounds 默认情况下是NO,如果,我们想要view2把超出的那部份隐藏起来的话,就得改变它的父视图也 就view1的clipsTobounds属性值。
view1.clipsTobounds = YES;
使用objective-c 建立UUID UUID是128位的值,它可以保证唯一性。通常,它是由机器本身网卡的MAC地
址和当前系统时间来生成的。 UUID是由中划线连接而成的字符串。例如:0A326293-BCDD-4788-8F2D-
C4D8E53C108B
在声明文件中声明一个方法:
#import
@interface UUIDViewController : UIViewController { }
- (NSString *) createUUID;
@end
对应的实现文件中实现该方法:
- (NSString *) createUUID {
CFUUIDRef uuidObject = CFUUIDCreate(kCFAllocatorDefault);
NSString *uuidStr = (NSString*)CFUUIDCreateString(kCFAllocatorDefault, uuidObject);
CFRelease(uuidObject);
return uuidStr; }
77、iPhone iPad中横屏显示代码
1、强制横屏
[applicationsetStatusBarOrientation:UIInterfaceOrientationLandscapeRightanimated:NO];
2、在infolist?里?面加了Supported interfaceorientations这?一项,增加之后添加四个item就是 ipad的四个?方向
item0 UIInterfaceOrientationLandscapeLeft
item1 UIInterfaceOrientationLandscapeRight 这表明只?支持横屏显?示 经常让人混淆迷惑的问题- 数组和其他集合类
78、当一个对象被添加到一个array, dictionary, 或者 set等这样的集合类型中的时候,集合会retain它。 对应的,当集合类被release的时候,它会发送对应的release消息给包含在其中的对象。 因此,如果你想建立一个包含一堆number的数组,你可以像下面示例中的几个方法来做
NSMutableArray *array; int i;
// ...
for (i = 0; i < 10; i++) {
NSNumber *n = [NSNumber numberWithInt: i];
[array addObject: n]; }
在这种情况下, 我们不需要retain这些number,因为array将替我们这么做。 NSMutableArray*array;
int i;
// ...
for (i = 0; i < 10; i++) {
NSNumber *n = [[NSNumber alloc] initWithInt: i];
[array addObject: n];
[n release];
}
在这个例子中,因为你使用了-alloc去建立了一个number,所以你必须显式的-release它,以保证retaincount的平衡。因为将number加入数组的时候,已经retain它了,所以数组中的number变量不会被release
79、UIView动画停止调用方法遇到的问题
在实现UIView的动画的时候,并且使?用UIView来重复调?用它结束的回调时候要注意以下?方法中的finished参数
-(void)animationDidStop:(NSString *)animationID finished:(NSNumber*)finished context:(void *)context
{
if([finishied boolValue] == YES)
//一定要判断这句话,要不在程序中当多个View刷新的时候,就可能出现动画异常的现象 {
//执行想要的动作 }
}
80、判断在UIViewController中,viewWillDisappear的时候是push还是 pop出来
- (void)viewWillDisappear:(BOOL)animated {
NSArray *viewControllers =self.navigationController.viewControllers; if(viewControllers.count > 1&& [viewControllers
objectAtIndex:viewControllers.count-2] == self) {
// View is disappearing because a new view controller was pushedonto the
stack
NSLog(@"New view controller was pushed");
} else if ([viewControllers indexOfObject:self] == NSNotFound) { //View is disappearing because it was popped from the stackNSLog(@"View controller was popped");
} }
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