好程序员-ios开发小知识点

1、获取系统语言设置NSUserDefaults*userDefault=[NSUserDefaultsstandardUserDefaults];NSArray*languages=[userDefaultobjectForKey:@"AppleLanguages"];NSString*preferredLang=[languagesobjectAtIndex:0]；2、缓存路径下文件大小-(unsignedlonglongint)cacheFolderSize{NSFileManager*_manager=[NSFileManagerdefaultManager];NSArray*_cachePaths=NSSearchPathForDirectoriesInDomains(NSCachesDirectory,

NSUserDomainMask,YES);NSString*_cacheDirectory=[_cachePathsobjectAtIndex:];NSArray*_cacheFileList;NSEnumerator*_cacheEnumerator;NSString*_cacheFilePath;unsignedlonglongint_cacheFolderSize=;_cacheFileList=[_managersubpathsAtPath:_cacheDirectory];_cacheEnumerator=[_cacheFileListobjectEnumerator];while(_cacheFilePath=[_cacheEnumeratornextObject]){NSDictionary*_cacheFileAttributes=[_managerfileAttributesAtPath:[_cacheDirectorystringByAppendingPathComponent:_cacheFilePath]traverseLink:YES];_cacheFolderSize+=[_cacheFileAttributesfileSize];}//单位是字节return_cacheFolderSize;}3、Popoverpush时Frame无法改变解决办法在popover中的ViewController中实现：-(void)viewWillAppear:(BOOL)animated

{CGSizesize=CGSizeMake(320,480);//sizeofviewinpopoverself.contentSizeForViewInPopover=size;[superviewWillAppear:animated];}4、tableview滑动导致NSTimer和委托回调停止解决办法//请求回调NSURLRequest*请求=...scheduleInRunLoop：[NSRunLoopcurrentRunLoop]

forMode：NSRunLoopCommonModes]

[连接开始]//定时器回调NSTimer*updateTimer=[NSTimerscheduledTimerWithTimeInterval：0.01f目标：自我选择：选择（updatePencent）的UserInfo：无重复：是];*NSRunLoop主要=[NSRunLoopcurrentRunLoop]

[主要addTimer：updateTimerforMode：NSRunLoopCommonModes];5、手势识别类UIGestureRecognizer6、SFHFKeychainUtils存储信息苹果SDK自带的就有密码保护，使用方法很简单，如下：1、引入Security.frameWork框架。2、引入头文件：SFHKeychainUtils.h.3、存密码：[SFHFKeychainUtilsstoreUsername:@"dd"andPassword:@"aa"forServiceName:SERVICE_NAMEupdateExisting:1error:nil];[SFHFKeychainUtilsdeleteItemForUsername:@"dd"andServiceName:SERVICE_NAMEerror:nil];4、取密码：NSString*passWord=[SFHFKeychainUtilsgetPasswordForUsername:@"dd"andServiceName:SERVICE_NAMEerror:nil];7、missingrequiredarchitecturei386infile解决办法在TargetInfo里面修改FrameworkSearchPasths删除里面内容就可以了。8、view放大缩小动画效果//创建缩小了的视图

myWeiBoImageVC=[[UIViewControlleralloc]init];

myWeiBoImageVC.view.clipsToBounds=YES;

myWeiBoImageVC.view.alpha=0.0;

myWeiBoImageVC.view.frame=CGRectMake(64,0,1024-64,768-20);

[self.viewaddSubview:myWeiBoImageVC.view];

CGAffineTransformnewTransform=

CGAffineTransformScale(myWeiBoImageVC.view.transform,0.1,0.1);

[myWeiBoImageVC.viewsetTransform:newTransform];

myWeiBoImageVC.view.center=CGPointMake(670,100);

[selfperformSelector:@selector(imageViewControllerBigAnimation)];

//放大刚刚创建缩小后的视图

-(void)imageViewControllerBigAnimation{

[UIViewbeginAnimations:@"imageViewBig"context:nil];

[UIViewsetAnimationDuration:0.5];

CGAffineTransformnewTransform=CGAffineTransformConcat(myWeiBoImageVC.view.transform,CGAffineTransformInvert(myWeiBoImageVC.view.transform));

[myWeiBoImageVC.viewsetTransform:newTransform];

myWeiBoImageVC.view.alpha=1.0;

myWeiBoImageVC.view.center=CGPointMake(416,510)；

[UIViewcommitAnimations];

}

//缩小视图隐藏

-(void)imageViewControllerSmallAnimation{

[UIViewbeginAnimations:@"imageViewSmall"context:nil];

[UIViewsetAnimationDuration:0.5];

CGAffineTransformnewTransform=CGAffineTransformScale(myWeiBoImageVC.view.transform,0.1,0.1);

[myWeiBoImageVC.viewsetTransform:newTransform];

myWeiBoImageVC.view.center=CGPointMake(670,100);

[UIViewcommitAnimations];

}9、UIScrollView控制View缩放allImageScrollView=[[UIScrollViewalloc]initWithFrame:CGRectMake(0,0,768,1024)];

allImageScrollView.minimumZoomScale=0.3;

allImageScrollView.maximumZoomScale=1.0;

allImageScrollView.backgroundColor=[UIColorclearColor];

allImageScrollView.delegate=self;

[self.viewaddSubview:allImageScrollView];

mPicStatusesViewController=[[PicStatusesViewControlleralloc]init];

[allImageScrollViewaddSubview:mPicStatusesViewController.view];

//UIScrollViewDelegete实现

-(UIView*)viewForZoomingInScrollView:(UIScrollView*)scrollView{

returnmPicStatusesViewController.view;//返回ScrollView上添加的需要缩放的视图

}

-(void)scrollViewDidZoom:(UIScrollView*)scrollView{

//缩放操作中被调用

}

-(void)scrollViewDidEndZooming:(UIScrollView*)scrollViewwithView:(UIView*)viewatScale:(float)scale{

//缩放结束后被调用

}10、iOS3.2播放视频NSString*urlString=[NSStringstringWithString:@"视频url"];NSURL*movieUrl=[[NSURLalloc]initWithString:urlString];

MPMoviePlayerController*myMoviePlayer=[[MPMoviePlayerControlleralloc]initWithContentURL:movieUrl];

myMoviePlayer.view.frame=CGRectMake(250,250,350,350);

[self.viewaddSubview:myMoviePlayer.view];

myMoviePlayer.shouldAutoplay=YES;

myMoviePlayer.scalingMode=MPMovieScalingModeAspectFit;

[myMoviePlayerplay];11、谷歌地图翻起动画效果CATransition*animation=[CATransitionanimation];

[animationsetDelegate:self];

[animationsetDuration:0.35];

[animationsetTimingFunction:UIViewAnimationCurveEaseInOut];

if(!curled){animation.type=@"pageCurl";

animation.fillMode=kCAFillModeForwards;

animation.endProgress=0.40;

}else{

animation.type=@"pageUnCurl";

animation.fillMode=kCAFillModeBackwards;

animation.startProgress=0.30;

}

[animationsetRemovedOnCompletion:NO];

[self.viewexchangeSubviewAtIndex:0withSubviewAtIndex:1];

[self.view.layeraddAnimation:animationforKey:@"pageCurlAnimation"];12、给View添加阴影和边框UIImageView*imgvPhoto=[UIImageViewalloc]init];

//添加边框

CALayer*layer=[_imgvPhotolayer];

layer.borderColor=[[UIColorwhiteColor]CGColor];

layer.borderWidth=5.0f;

//添加四个边阴影

_imgvPhoto.layer.shadowColor=[UIColorblackColor].CGColor;

_imgvPhoto.layer.shadowOffset=CGSizeMake(0,0);

_imgvPhoto.layer.shadowOpacity=0.5;

_imgvPhoto.layer.shadowRadius=10.0;

//添加两个边阴影

_imgvPhoto.layer.shadowColor=[UIColorblackColor].CGColor;

_imgvPhoto.layer.shadowOffset=CGSizeMake(4,4);

_imgvPhoto.layer.shadowOpacity=0.5;

_imgvPhoto.layer.shadowRadius=2.0;13、使用NSTimer与UIView动画实现飘雪效果viewDidLoad事件中，增加一个图片及定时器并启动,这里的pic请在头文件中定义。-(void)viewDidLoad{

[superviewDidLoad];

self.pic=[UIImageimageNamed:@"snow.png"];//初始化图片

//启动定时器，实现飘雪效果

[NSTimerscheduledTimerWithTimeInterval:(0.2)target:selfselector:@selector(ontime)userInfo:nilrepeats:YES];

}然后再实现定时器定时调用的ontime方法：

-(void)ontime{

UIImageView*view=[[UIImageViewalloc]initWithImage:pic];//声明一个UIImageView对象，用来添加图片

view.alpha=0.5;//设置该view的alpha为0.5，半透明的

intx=round(random()20);//随机得到该图片的x坐标

inty=round(random()20);//这个是该图片移动的最后坐标x轴的

ints=round(random())+10;//这个是定义雪花图片的大小

intsp=1/round(random()0)+1;//这个是速度

view.frame=CGRectMake(x,-50,s,s);//雪花开始的大小和位置

[self.viewaddSubview:view];//添加该view

[UIViewbeginAnimations:nilcontext:view];//开始动画

[UIViewsetAnimationDuration:10*sp];//设定速度

view.frame=CGRectMake(y,500,s,s);//设定该雪花最后的消失坐标

[UIViewsetAnimationDelegate:self];

[UIViewcommitAnimations];

}14、配置Xcode看程序崩溃信息1、在xcode中的左侧目录中找到Executables打开2、双击和工程名一样的文件。3、在打开的文件中的Arguments选项，在下面的框中加入Name：NSZombieEnabled设置value为YES。15、程序中发送邮件和检测设备邮箱是否被配置-(void)addEmail{ClassmailClass=(NSClassFromString(@"MFMailComposeViewController"));if(mailClass!=nil){if([mailClasscanSendMail]){[selfdisplayComposerSheet];}else{[selflaunchMailAppOnDevice];}}else{[selflaunchMailAppOnDevice];}}-(void)displayComposerSheet{MFMailComposeViewController*controller=[[MFMailComposeViewControlleralloc]init];controller.navigationBar.tag=1002;[self.navigationController.navigationBarsetNeedsDisplay];controller.mailComposeDelegate=self;[controllersetSubject:@"意见反馈"];[controllersetToRecipients:[[NSArrayalloc]initWithObjects:@"555@",nil]];NSString*emailBody=nil;[controllersetMessageBody:emailBodyisHTML:YES];[selfpresentModalViewController:controlleranimated:YES];[controllerrelease];}#pragmamarkmailComposeDelegate(void)mailComposeController:(MFMailComposeViewController*)controllerdidFinishWithResult:(MFMailComposeResult)resulterror:(NSError*)error{if(result==MFMailComposeResultSent){[selfdismissModalViewControllerAnimated:YES];}if(result==MFMailComposeResultSaved){[selfdismissModalViewControllerAnimated:YES];}if(result==MFMailComposeResultFailed){Emailalert=[[UIAlertViewalloc]initWithTitle:@""message:@"发送失败"delegate:se