iOS开发经常用到的技术知识点
1.刷新单个tableviewcell
NSIndexPath * indexPat=[NSIndexPath indexPathForRow:indexPlay inSection:0];
NSArray * indexArray=[NSArray arrayWithObject:indexPat];
[self.tableView reloadRowsAtIndexPaths:indexArray withRowAnimation:UITableViewRowAnimationAutomatic];
2. 判断该方法是否执行？？
BOOL isss= [cell.queuePlayer respondsToSelector:@selector(play)];
int (^oneFrom)(int) = ^(int anInt) {
return anInt -1;
};
NSLog(@"%d",oneFrom(10));
4. 改变buuton的高亮
UIImageView * iv = [[UIImageView alloc] initWithFrame:CGRectMake(250, 5, 50, 34)];
iv.userInteractionEnabled = YES;
UIButton * navBtn = [UIButton buttonWithType:UIButtonTypeCustom];
navBtn.frame = CGRectMake(0, 0, 50, 34);
[navBtn setImage:[UIImage imageNamed:@"rong_Tian"] forState:UIControlStateNormal];
[navBtn setHighlighted:YES];
[navBtn addTarget:self action:@selector(btnPressed:) forControlEvents:UIControlEventTouchUpInside];
[navBtn setShowsTouchWhenHighlighted:YES];
[iv addSubview:navBtn];
[self.navigationController.navigationBar addSubview:iv];
5. 默认为cell第一行
NSIndexPath *first=[NSIndexPath indexPathForRow:0 inSection:0];
[self.tableView selectRowAtIndexPath:first animated:YES scrollPosition:UITableViewScrollPositionBottom];
6.一个项目中 ARC和非ARC 的混合使用
点击项目--》TARGETS-》Build Phases -》Compile Sources 中选择要改的.m 双击 在标签中写：
1.如果是ARC项目，要加入非ARC的代码文件 fobjc-arc
2.如果是非ARC，要加入ARC的代码 -fno-objc-arc Enter就OK
// NSURL * url=[NSURL URLWithString:str];
//
// NSURLRequest *requestt = [[NSURLRequest alloc]initWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
// NSData *received = [NSURLConnection sendSynchronousRequest:requestt returningResponse:nil error:nil];
// NSString *strr = [[NSString alloc]initWithData:received encoding:NSUTF8StringEncoding];
// NSLog(@"这是 成功返回的信息 %@",strr);
7.距离感应器
UIDeviceOrientation orientation3= [[UIDevice currentDevice] orientation];
NSLog(@"获取当前状态 %d",orientation3);
[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(sensorStateChange:)
name:@"UIDeviceProximityStateDidChangeNotification"
object:nil];
-(void)sensorStateChange:(NSNotificationCenter *)notification;
{
if ([[UIDevice currentDevice] proximityState] == YES) {
NSLog(@"Device is close to user");
//在此写接近时，要做的操作逻辑代码
}else{
NSLog(@"Device is not close to user");
}
}
8.获得cookie
NSHTTPCookieStorage *cookieJar = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (NSHTTPCookie *cookie in [cookieJar cookies]) {
NSLog(@"cookie＝＝＝＝＝ %@", cookie);
}
9.从相册中只获得视频文件
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary] == YES)
{
UIImagePickerController *videoLibraryController = [[[UIImagePickerController alloc] init] autorelease];
videoLibraryController.delegate = self;
videoLibraryController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
videoLibraryController.mediaTypes = [NSArray arrayWithObject:(NSString *)kUTTypeMovie];
[videoLibraryController setAllowsEditing:YES];
[self.navigationController presentViewController:videoLibraryController animated:YES completion:^{
}];
}
else
{
[self AlertlogError:@"暂时你还没有视频"];
}
10. 读取全局的Delegate：
KiloNetAppDelegate *appdelegate = (KiloNetAppDelegate *)[[UIApplication sharedApplication] delegate];
11.键盘透明
textField.keyboardAppearance = UIKeyboardAppearanceAlert;Error Domain=ASIHTTPRequestErrorDomain Code=5 "Unable to create request (bad url?)" UserInfo=0x69ba0f0 {NSLocalizedDescription=Unable to create request (bad url?)}
解决办法：
NSString*url =@"http://oerp.xixingsoft.com:8083/oadata/MobileConfig.nsf/GetStandList?openagent&ViewNumber=新闻中心";
url=[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSStringEncodingenc = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);//gbk code-->utf8 code
NSData*data = [url dataUsingEncoding:NSUTF8StringEncoding];//[request responseData];
NSString*utf8str = [[[NSStringalloc] initWithData:data encoding:enc] autorelease];
13.请求中加cookie、 heard
当你需要添加更多的请求信息时，如，添加个请求Header：
[request addRequestHeader:@"name" value:@"Jory lee"];
14 Plist文件的保存 修改 除非在decument是可读可写的（在工程中 可读不可写）
//获取路径对象
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
//获取完整路径
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *plistPath = [documentsDirectory stringByAppendingPathComponent:@"test.plist"];
NSLog(@"plist 地质 %@",plistPath);
NSMutableDictionary *dictplist = [[NSMutableDictionary alloc ] init];
[dictplist setObject:self.strWeb_id forKey:@"web_id"];
[dictplist writeToFile:plistPath atomically:YES];
15.获取文件夹的大小
-(long long) fileSizeAtPath:(NSString*) filePath{
NSFileManager* manager = [NSFileManager defaultManager];
if ([manager fileExistsAtPath:filePath]){
return [[manager attributesOfItemAtPath:filePath error:nil] fileSize];
}
return 0;
}
16.改变tablevlewcell点击的颜色
cell.selectedBackgroundView = [[[UIView alloc] initWithFrame:cell.frame] autorelease];
cell.selectedBackgroundView.backgroundColor = [UIColor colorWithRed:54/255.0f green:110/255.0f blue:100/255.0f alpha:1.0f];
字
cell.textLabel.highlightedTextColor = [UIColor xxxcolor]; [cell.textLabel setTextColor:color
点击后，过段时间cell自动取消选中
[self performSelector:@selector(deselect) withObject:nil afterDelay:0.5f];
- (void)deselect
{
[self.tableVieww deselectRowAtIndexPath:[self.tableVieww indexPathForSelectedRow] animated:YES];
}
17.改变UITableViewStyleGrouped背景颜色
self.tableVieww.backgroundColor =[UIColor colorWithPatternImage:[UIImage imageNamed:@"更多背景图.png"]];
self.tableVieww.backgroundView =nil;
18.视图反转
//水平
queuePlayer.transform = CGAffineTransformScale(queuePlayer.transform, 1.0, -1.0);
//垂直 queuePlayer.transform = CGAffineTransformScale(queuePlayer.transform, -1.0, 1.0);
19.改变icon的阴影圆圈，取消图标上的高光
1.进入plist文件 2.在Supported interface orientations 添加 Icon already includes gloss effects 设置为YES 也就是用自己的icon，不用系统的了
20.动态UIlable后添加图片
self.userNameLabel=[[[UILabel alloc]initWithFrame:CGRectMake(60, 7, 220, 20)]autorelease];
self.userNameLabel.textColor= [UIColor blackColor];
self.userNameLabel.text=self.strNamee;
self.userNameLabel.backgroundColor=[UIColor clearColor];
self.userNameLabel.numberOfLines=0;
UIFont *font = [UIFont fontWithName:@"Helvetica-Bold" size:17.0f];
[self.userNameLabel setFont:font];
[self.contentView addSubview:self.userNameLabel];
CGSize size = [self.strNamee sizeWithFont:font constrainedToSize:CGSizeMake(277, 20.0f)];
NSLog(@"kuang %f ",size.width);
CGRect rect=self.userNameLabel.frame;
rect.size=size;
NSLog(@"321 %f %f",rect.size.width,rect.size.height);
[self.userNameLabel setFrame:rect];
//判断男女
UIImageView * imaSex=[[UIImageView alloc]initWithFrame:CGRectMake(self.userNameLabel.frame.size.width+65, 10, 12, 13)];
21.向自定义的cell中传值，最好用 方法在tableview中来调用 如果有参数 直接来传//时间差
- (NSString *)intervalSinceNow: (NSString *) theDate
{
NSDateFormatter *date=[[NSDateFormatter alloc] init];
[date setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
NSDate *d=[date dateFromString:theDate];
NSTimeInterval late=[d timeIntervalSince1970]*1;
NSDate* dat = [NSDate dateWithTimeIntervalSinceNow:0];
NSTimeInterval now=[dat timeIntervalSince1970]*1;
NSString *timeString=@"";
NSTimeInterval cha=now-late;
if (cha/3600<1) {
timeString = [NSString stringWithFormat:@"%f", cha/60];
timeString = [timeString substringToIndex:timeString.length-7];
timeString=[NSString stringWithFormat:@"%@分钟前", timeString];
}
if (cha/3600>1&&cha/86400<1) {
timeString = [NSString stringWithFormat:@"%f", cha/3600];
timeString = [timeString substringToIndex:timeString.length-7];
timeString=[NSString stringWithFormat:@"%@小时前", timeString];
}
if (cha/86400>1)
{
timeString = [NSString stringWithFormat:@"%f", cha/86400];
timeString = [timeString substringToIndex:timeString.length-7];
timeString=[NSString stringWithFormat:@"%@天前", timeString];
}
[date release];
return timeString;
}
22.按钮在cell上单击第几行
在cell.contentView上：
//获得row
NSInteger row = [[self.tableView indexPathForCell:(UITableViewCell *)[[sender superview] superview]] row];
//获得section
NSInteger row = [[self.tableView indexPathForCell:(UITableViewCell *)[[sender superview] superview]] section];
//获得indexPath
NSIndexPath *indexPath = [self.tableView indexPathForCell:(UITableViewCell *)[[sender superview] superview]];
[[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(rongTianOrientation:) name:@"UIDeviceOrientationDidChangeNotification" object:nil];
- (void) deviceOrientationDidChangeAction:(NSNotification *)note
{
NSInteger currentOrientation = [[note object] orientation];
switch (currentOrientation) {
case0: { //未知方向
break;
}
case1: { //home键向下
break;
}
case2: { //home键向上
break;
}
case3: { //home键向左
break;
}
case4: { //home键向右
break;
}
default:
break;
}
}
24.模拟器不能运行的错误
dyld: Library not loaded: @rpath/SenTestingKit.framework/Versi*****/A/SenTestingKit
Referenced from: /Users/⋯⋯/Application Support/iPhone Simulator/5.0/Applicati*****/F179924C-0EB7-4CCA-88D6-3BA1F68F122D/ILUTU.app/ILUTU
Reason: image not found
把SentestingKit。 frameWork 有原来的required改为Optional 就ok
25.还原状态栏
显示原来的状态栏
（1）
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:YES];
[[UIApplication sharedApplication].keyWindow setFrame:CGRectMake(0, 20, 320, [UIScreen mainScreen].applicationFrame.size.height)];
//重新设定标题栏显示的位置
[self.navigationController.navigationBar setFrame:CGRectMake(0, 0, 320, 44)];
（2）
在别的页面[[UIApplication sharedApplication].keyWindow setFrame:CGRectMake(0, 0, 320, [UIScreenmainScreen].applicationFrame.size.height)];
- (int)getVideopTime:(NSURL * )videourl
{
NSDictionary *opts = [NSDictionary dictionaryWithObject:[NSNumbernumberWithBool:NO]
forKey:AVURLAssetPreferPreciseDurationAndTimingKey];
AVURLAsset *urlAsset = [AVURLAsset URLAssetWithURL:videourl options:opts]; //初始化视频媒体文件
int minute = 0, second = 0;
second = urlAsset.duration.value / urlAsset.duration.timescale; // 获取视频总时长,单位秒
NSLog(@"movie duration : %d", second);
if (second >= 60) {
int index = second / 60;
minute = index;
second = second - index*60;
}
return second;
}
27.视频播放器 循环播放 大小……
(1) MPMoviePlayerController
MPMoviePlayerController *player;
NSURL *url =[NSURL URLWithString:fileName];
player = [[MPMoviePlayerController alloc] init];
player.view.frame = CGRectMake(10, 30, 300 , 225);
player.contentURL = url;
player.repeatMode = MPMovieRepeatModeOne;
player.controlStyle = MPMovieControlStyleEmbedded;
player.scalingMode = MPMovieScalingModeAspectFill; //充满屏幕
[self.view addSubview:player.view];
[player play];
(2).avplayer
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(playerItemDidReachEnd:) name:AVPlayerItemDidPlayToEndTimeNotification
object:plaitem];
}
}];
#pragma mark - Notification Callbacks
- (void)playerItemDidReachEnd:(NSNotification *)notification {
NSLog(@"是跳转第一侦吗？ ");
[self.queuePlayer seekToTime:kCMTimeZero];
[self.queuePlayer play];
}
28.sina微博错误返回值格式
http://open.weibo.com/wiki/Error_code
29.ios 获得文件夹的大小
//计算文件夹下文件的总大小
-(long)fileSizeForDir:(NSString*)path
{
NSFileManager *fileManager = [[NSFileManager alloc] init];
long size = 0;
NSArray* array = [fileManager contentsOfDirectoryAtPath:path error:nil];
for(int i = 0; i<[array count]; i++)
{
NSString *fullPath = [path stringByAppendingPathComponent:[array objectAtIndex:i]];
BOOL isDir;
if ( !([fileManager fileExistsAtPath:fullPath isDirectory:&isDir] && isDir) )
{
NSDictionary *fileAttributeDic=[fileManager attributesOfItemAtPath:fullPath error:nil];
size+= fileAttributeDic.fileSize;
} else {
[self fileSizeForDir:fullPath];
}
}
[fileManager release]; return size; }
30. 谓词过滤
//搜索用谓词过滤数组
NSArray * arrMy=@[@"张2荣三a",@"李四b",@"王五a",@"李流j",@"荣天321",@"iOS基地",@"iOS7"];
NSString * strg=@"荣";
NSPredicate * fiecate=[NSPredicate predicateWithFormat:@"SELF CONTAINS %@",strg];
NSArray * arr3=[arrMy filteredArrayUsingPredicate:fiecate];
NSLog(@"这是我过滤的数组对吗？%@",arr3);
31.多线程的多种创建
// NSThread * th=[[NSThread alloc]initWithTarget:self selector:@selector(thAction) object:nil];
// [th start];
//[NSThread detachNewThreadSelector:@selector(thAction) toTarget:self withObject:nil];
// [self performSelectorInBackground:@selector(thAction) withObject:self];
// NSOperationQueue * operationQueue=[[NSOperationQueue alloc]init];
// [operationQueue addOperationWithBlock:^{
// for(int i=0; i<20;i++){
// NSLog(@"This isThread: %d",i);
// }
// }];
// NSOperationQueue * operationQueue=[[NSOperationQueue alloc]init];
// //设置线程池中的并发数
// operationQueue.maxConcurrentOperationCount=1;
//
// NSInvocationOperation * invocation1=[[NSInvocationOperation alloc]initWithTarget:self selector:@selector(threadOne) object:nil];
// [invocation1 setQueuePriority:NSOperationQueuePriorityLow];
//
// NSInvocationOperation * invocation2=[[NSInvocationOperation alloc]initWithTarget:self selector:@selector(threadTwo) object:nil];
// [invocation2 setQueuePriority:NSOperationQueuePriorityHigh];
// [operationQueue addOperation:invocation1];
// [operationQueue addOperation:invocation2];
32.用多线程开启Nstimer提高精确度
//用多线程开启nstimer提高精确度
- (void)mutiThread
{
NSLog(@"Start NStimer");
@autoreleasepool {
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timerAction:) userInfo:nil repeats:YES];
}
//获得当前的runloop，线程就停在这里
[[NSRunLoop currentRunLoop]run];
NSLog(@"after");
}
- (void)timerAction:(NSTimer * )timer
{
i++;
NSLog(@"Print NSTimer");
if (i==5) {
[timer invalidate];
}
}
33.判断此页面是push，还是模态过来的
if (self.presentingViewController) {
NSLog(@"这个是模态过来的！");}
34。等比例放大缩小视图
UILabel * la=(UILabel * )[self.view viewWithTag:908];
[UIView animateWithDuration:.5 animations:^{
CGAffineTransform transform=la.transform;
transform=CGAffineTransformScale(la.transform, 1.5, 1.5);
la.transform=transform;
} completion:^(BOOL finished) {
CGAffineTransform transform=la.transform;
transform=CGAffineTransformScale(la.transform, 0.5, 0.5);
la.transform=transform;
}];
35.清掉编译文件
~/Library/Developer/Xcode/DerivedData
模拟器清空编译
~/Library/Application Support/iPhone Simulator/
36.改变状态栏的颜色状态
[[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleDefault];
[[UIApplication sharedApplication] setStatusBarHidden:NO];
37.给自己的项目中添加特殊的标示符号
http://patorjk.com/software/taag/#p=moreopts&h=0&v=1&f=优雅&t=V
38 清空某个文件夹
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *outputURL = paths[0];
[NSFileManager.new removeItemAtPath:outputURL error:nil];
[NSFileManager.new createDirectoryAtPath:outputURL
withIntermediateDirectories:YES
attributes:nil
error:NULL];
39. 在document下创建文件
NSString *writePath=[NSString stringWithFormat:@"%@/%@.txt",stre,@"aaa"];
NSData *data = [@"" dataUsingEncoding:NSUTF8StringEncoding];//新文件的初始数据，设为空
[[NSFileManager defaultManager] createFileAtPath:writePath contents:data attributes:nil];//创建文件的命令在这里
40.layoutSubviews在以下情况下会被调用：
1、init初始化不会触发layoutSubviews
2、addSubview会触发layoutSubviews
3、设置view的Frame会触发layoutSubviews，当然前提是frame的值设置前后发生了变化
4、滚动一个UIScrollView会触发layoutSubviews
5、旋转Screen会触发父UIView上的layoutSubviews事件
6、改变一个UIView大小的时候也会触发父UIView上的layoutSubviews事件
41.苹果审核加急通道
https://developer.apple.com/appstore/contact/?topic=expedite
51 .美化配置git log
$ git config --global alias.lg "log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --" $ git lg
52.查看远程 git
git remote show origin
53.显示远程git仓库
git remote show
54.OC冒泡排序
// NSMutableArray 自带排序方法 NSMutableArray *lastArrary = [NSMutableArray arrayWithArray:sinceArray]; [lastArrary sortedArrayUsingSelector:@selector(compare:)]; - (NSComparisonResult)compare:(NSNumber *)otherNumber { // 设置升 降序 return NSOrderedDescending; }
// 冒泡排序 NSMutableArray *sinM_Array = [NSMutableArray arrayWithArray:sinceArray]; for (int x = 0; x < sinceArray.count -1; x ++) { for (int y = x + 1; y < sinceArray.count - 1 -x; y ++) { int leftNum = [[sinM_Array objectAtIndex:x] intValue]; int rightNum = [[sinM_Array objectAtIndex:y]intValue]; if (leftNum > rightNum) { [sinM_Array replaceObjectAtIndex:x withObject:[NSNumber numberWithInt:leftNum]]; [sinM_Array replaceObjectAtIndex:y withObject:[NSNumber numberWithInt:rightNum]]; } } }
55.前后摄像头的切换
- (AVCaptureDevice *)cameraWithPosition:(AVCaptureDevicePosition)position
{
NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
for ( AVCaptureDevice *device in devices )
if ( device.position == position )
return device;
return nil;
}
- (void)backCarme:(UIButton *)button
{
NSArray *inputs = self.session.inputs;
for ( AVCaptureDeviceInput *input in inputs ) {
AVCaptureDevice *device = input.device;
if ( [device hasMediaType:AVMediaTypeVideo] ) {
AVCaptureDevicePosition position = device.position;
AVCaptureDevice *newCamera = nil;
AVCaptureDeviceInput *newInput = nil;
if (position == AVCaptureDevicePositionFront)
newCamera = [self cameraWithPosition:AVCaptureDevicePositionBack];
else
newCamera = [self cameraWithPosition:AVCaptureDevicePositionFront];
newInput = [AVCaptureDeviceInput deviceInputWithDevice:newCamera error:nil];
[self.session beginConfiguration];
[self.session removeInput:input];
[self.session addInput:newInput];
[self.session commitConfiguration];
break;
}
}
}
56.#pragma mark --获得视频的尺寸
-(CGSize)getImage:(NSURL *)url
{
NSDictionary *opts = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO]forKey:AVURLAssetPreferPreciseDurationAndTimingKey];
AVURLAsset *urlAsset = [AVURLAsset URLAssetWithURL:url options:opts];
CGSize size = [[[urlAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] naturalSize];
return size;
}
57.播放音频
// 导入框架 AudioToolbox.framework
NSString *path = [[NSBundle mainBundle] pathForResource:@"msgcome" ofType:@"wav"];
NSURL *url = [NSURL fileURLWithPath:path];
SystemSoundID soundId;
AudioServicesCreateSystemSoundID((CFURLRef)url, &soundId);
AudioServicesPlaySystemSound(soundId);
原文地址：http://blog.sina.com.cn/s/blog_801997310101cthq.html