ios 技巧点

1.手势

[A requireGestureRecognizerToFail：B]函数，它可以指定当A手势发生时，即便A已经滿足条件了，也不会立刻触发，会等到指定的手势B确定失败之后才触发

2. UISCrollView 添加swipe手势

      1.给手势识别器设置代理， 2.实现代理的方法，都返回为yes

3. 在导航上方设置个提示框

localNavigationController.tabBarItem.badgeValue = [NSString stringWithFormat:@"%d", badgeCount];

导航标题的设置： self.navigationBar.topItem.title = @"Synchronous Requests";

4. 自定义 导航推出界面 的动画

- (void) showLoginView{    [mNavigationController setNavigationBarHidden:NO animated:NO];    CATransition *animation = [CATransition animation];    [animation setDuration:0.5f];    [animation setType: kCATransitionPush];    [animation setSubtype: kCATransitionFromTop];    animation.timingFunction = UIViewAnimationCurveEaseInOut;        LoginViewController *loginController = [[LoginViewController alloc] init];    [mNavigationController pushViewController:loginController animated:NO];    [mNavigationController.view.layer addAnimation:animation forKey:nil];    [mainWindow insertSubview:mNavigationController.view atIndex:0];}

1 随机数的使用

        头文件的引用
        #import <time.h>
        #import <mach/mach_time.h>

        srandom()的使用
        srandom((unsigned)(mach_absolute_time() & 0xFFFFFFFF));

        直接使用 random() 来调用随机数

2 在UIImageView 中旋转图像

       float rotateAngle = M_PI;
        CGAffineTransform transform =CGAffineTransformMakeRotation(rotateAngle);
        imageView.transform = transform;
       
        以上代码旋转imageView, 角度为rotateAngle, 方向可以自己测试哦！

3 在Quartz中如何设置旋转点

        UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"bg.png"]];
        imageView.layer.anchorPoint = CGPointMake(0.5, 1.0);

        这个是把旋转点设置为底部中间。记住是在QuartzCore.framework中才得到支持。

4 创建.plist文件并存储

        NSString *errorDesc;  //用来存放错误信息
        NSMutableDictionary *rootObj = [NSMutableDictionary dictionaryWithCapacity:4]; //NSDictionary, NSData等文件可以直接转化为plist文件
        NSDictionary *innerDict;
        NSString *name;
        Player *player;
        NSInteger saveIndex;
    
        for(int i = 0; i < [playerArray count]; i++) {
              player = nil;
              player = [playerArray objectAtIndex:i];
              if(player == nil)
                     break; 
              name = player.playerName;// This "Player1" denotes the player name could also be the computer name
              innerDict = [self getAllNodeInfoToDictionary:player];
              [rootObj setObject:innerDict forKey:name]; // This "Player1" denotes the person who start this game
        }
        player = nil;
        NSData *plistData = [NSPropertyListSerialization dataFromPropertyList:(id)rootObj format:NSPropertyListXMLFormat_v1_0 errorDescription:&errorDesc];

        红色部分可以忽略，只是给rootObj添加一点内容。这个plistData为创建好的plist文件，用其writeToFile方法就可以写成文件。下面是代码：
        
        /*得到移动设备上的文件存放位置*/
        NSString *documentsPath = [self getDocumentsDirectory]; 
        NSString *savePath = [documentsPath stringByAppendingPathComponent:@"save.plist"];
    
        /*存文件*/
        if (plistData) {
                [plistData writeToFile:savePath atomically:YES];
         }
         else {
                NSLog(errorDesc);
                [errorDesc release];
        }

        - (NSString *)getDocumentsDirectory {  
                NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);  
                return [paths objectAtIndex:0];  
        } 

4 读取plist文件并转化为NSDictionary

        NSString *documentsPath = [self getDocumentsDirectory];
        NSString *fullPath = [documentsPath stringByAppendingPathComponent:@"save.plist"];
        NSMutableDictionary* plistDict = [[NSMutableDictionary alloc] initWithContentsOfFile:fullPath];

5 读取一般性文档文件

        NSString *tmp;
        NSArray *lines; /*将文件转化为一行一行的*/
        lines = [[NSString    stringWithContentsOfFile:@"testFileReadLines.txt"] 
                       componentsSeparatedByString:@"\n"];
    
         NSEnumerator *nse = [lines objectEnumerator];
    
         // 读取<>里的内容
         while(tmp = [nse nextObject]) {
                  NSString *stringBetweenBrackets = nil;
                  NSScanner *scanner = [NSScanner scannerWithString:tmp];
                  [scanner scanUpToString:@"<" intoString:nil];
                  [scanner scanString:@"<" intoString:nil];
                  [scanner scanUpToString:@">" intoString:&stringBetweenBrackets];

                  NSLog([stringBetweenBrackets description]);
          }

对于读写文件，还有补充，暂时到此。随机数和文件读写在游戏开发中经常用到。所以把部分内容放在这，以便和大家分享，也当记录，便于查找。

6 隐藏NavigationBar

[self.navigationController setNavigationBarHidden:YES animated:YES];
在想隐藏的ViewController中使用就可以了。

7. 设置cell的点击效果

UIImageview * imgv = ；

cell.selectedBackgroundView = imgv;

didselected： 中加入[tableView deselectRowAtIndexPath:indexPath animated:YES]; //实现动画效果

8 导航的常见设置

[UINavigationBar appearance]  setBackgroundImage: ]; //导航背景

[UINavigationBar appearance]  setTitleTextAttritudes: ]; // 导航字体

[UIBarButtonItem appearance] setBackgroundImage: ] ;   // 导航按钮背景

[UIBarButtonItem appearance] setBackButtonBackgoundImage: ]; // 导航返回按钮背景

[UITabBar appearance]  setBackgroundImage: ]; // TabBar 背景

[UITabBar appearance]  setSelectionIndicatorImage:];// TabBar 选中图标

9.slider滑轮左右侧图片，滚轮本身图片

[UISlider appearance] setMaximumtrackImage: ];

[UISlider appearance] setMinimumtrackImage: ];

[UISlider appearance] ]setThumbImage: ] ;

10: UISegment背景，间隔部分图片

[UISegmentedControl appearance]setBackgroundImage];

[UISegmentedControl appearance]setDividerImage];

11:UISwitch打开的时候的背景颜色 

[UISwitch  appearance] setOnTintColor:];