分段控件是我们常用的控件之一，今天把具体用法总结了下：

          1.初始化UISegmentedControl

 NSArray *segmentedArray = [[NSArray alloc]initWithObjects:@"1",@"2",@"3",nil];
 UISegmentedControl *segmentedTemp = [[UISegmentedControl alloc]initWithItems:segmentedArray];
 self.segmentedControl = segmentedTemp;
 segmentedControl.frame = CGRectMake(10.0, 10.0, 300.0, 29.0);

      2.常用属性及设置方法如下：
 //设置指定索引的题目
 [segmentedControl setTitle:@"1" forSegmentAtIndex:1];
 //设置指定索引的图片
 [segmentedControl setImage:[UIImage imageNamed:@"home.png"] forSegmentAtIndex:2];
 //在指定索引插入一个选项并设置图片
 [segmentedControl insertSegmentWithImage:[UIImage imageNamed:@"more.png"] atIndex:2 animated:NO];
 //在指定索引插入一个选项并设置题目
 [segmentedControl insertSegmentWithTitle:@"new" atIndex:3 animated:NO];
 //移除指定索引的选项
 [segmentedControl removeSegmentAtIndex:0 animated:NO];
 //设置指定索引选项的宽度
 [segmentedControl setWidth:60.0 forSegmentAtIndex:2];
 //设置选项中图片等的左上角的位置
 //[segmentedControl setContentOffset:CGSizeMake(10.0,10.0) forSegmentAtIndex:1];

 //设置默认选择项索引
 segmentedControl.selectedSegmentIndex = 2;
 //分段控件的颜色，只有样式为UISegmentedControlStyleBar的时候才有效果
 segmentedControl.tintColor = [UIColor redColor];
 //设置样式
 segmentedControl.segmentedControlStyle = UISegmentedControlStyleBordered;
 //设置在点击后是否恢复原样
 segmentedControl.momentary = NO;
 //设置指定索引选项不可选
 [segmentedControl setEnabled:NO forSegmentAtIndex:3];
 //判断指定索引选项是否可选
 BOOL enableFlag = [segmentedControl isEnabledForSegmentAtIndex:3];
 NSLog(@"%d",enableFlag);

        3.分段控件点击事件：

 [segmentedControl addTarget:self
                      action:@selector(segmentAction:)
            forControlEvents:UIControlEventValueChanged];

        响应的事件：

 -(void)segmentAction:(UISegmentedControl *)Seg
 {
     NSInteger index = Seg.selectedSegmentIndex;
     switch (index) {
         case 0:
             NSLog(@"0 clicked.");
             break;
         case 1:
             NSLog(@"1 clicked.");
             break;
         case 2:
             NSLog(@"2 clicked.");
             break;
         case 3:
             NSLog(@"3 clicked.");
             break;
         case 4:
             NSLog(@"4 clicked.");
             break;
         default:
             break;
     }
 }

         4.获取分段控件相应的值：

 //获取指定索引选项的图片imageForSegmentAtIndex：
 UIImageView *imageForSegmentAtIndex = [[UIImageView alloc]initWithImage:[segmentedControl imageForSegmentAtIndex:1]];
 imageForSegmentAtIndex.frame = CGRectMake(60.0, 100.0, 30.0, 30.0);

 //获取指定索引选项的标题titleForSegmentAtIndex
 UILabel *titleForSegmentAtIndex = [[UILabel alloc]initWithFrame:CGRectMake(100.0, 100.0, 30.0, 30.0)];
 titleForSegmentAtIndex.text = [segmentedControl titleForSegmentAtIndex:0];

 //获取总选项数segmentedControl.numberOfSegments
 UILabel *numberOfSegments = [[UILabel alloc]initWithFrame:CGRectMake(140.0, 100.0, 30.0, 30.0)];
 numberOfSegments.text = [NSString stringWithFormat:@"%d",segmentedControl.numberOfSegments];

 //获取指定索引选项的宽度widthForSegmentAtIndex：
 UILabel *widthForSegmentAtIndex = [[UILabel alloc]initWithFrame:CGRectMake(180.0, 100.0, 70.0, 30.0)];
 widthForSegmentAtIndex.text = [NSString stringWithFormat:@"%f",[segmentedControl widthForSegmentAtIndex:2]];

         但是这样的分段控件只有固定的几种样式。在IOS5以后，可以全局的设置一些控件的外观，分段控件就是其中一个（全局设置UISegmentedControl外观）：

 //cap insets用来指定哪些区域是固定不变的，未制定的区域则会repeat

 UIImage *segmentSelected = [[UIImage imageNamed:@"bg_o.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(5, 5, 5, 5)];

 UIImage *segmentUnselected = [[UIImage imageNamed:@"bg.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(5, 5, 5, 5)];

 UIImage *segmentSelectedUnselected = [UIImage imageNamed:@"line.png"] ;

 UIImage *segUnselectedSelected = [UIImage imageNamed:@"line.png"] ;

 UIImage *segmentUnselectedUnselected = [UIImage imageNamed:@"line.png"];

 //Segmente未选中背景
 [[UISegmentedControl appearance] setBackgroundImage:segmentUnselected
                                            forState:UIControlStateNormal
                                          barMetrics:UIBarMetricsDefault];

 //Segmente选中背景
 [[UISegmentedControl appearance] setBackgroundImage:segmentSelected
                                            forState:UIControlStateSelected
                                          barMetrics:UIBarMetricsDefault];

 //Segmente左右都未选中时的分割线
 //BarMetrics表示navigation bar的状态，UIBarMetricsDefault 表示portrait状态（44pixel height），UIBarMetricsLandscapePhone 表示landscape状态（32pixel height）

 [[UISegmentedControl appearance] setDividerImage:segmentUnselectedUnselected
                              forLeftSegmentState:UIControlStateNormal
                                rightSegmentState:UIControlStateNormal
                                       barMetrics:UIBarMetricsDefault];

 [[UISegmentedControl appearance] setDividerImage:segmentSelectedUnselected
                              forLeftSegmentState:UIControlStateSelected
                                rightSegmentState:UIControlStateNormal
                                       barMetrics:UIBarMetricsDefault];

 [[UISegmentedControl appearance] setDividerImage:segUnselectedSelected
                              forLeftSegmentState:UIControlStateNormal
                                rightSegmentState:UIControlStateSelected
                                       barMetrics:UIBarMetricsDefault];

 //字体
 NSDictionary *textAttibutesUnSelected = [NSDictionary dictionaryWithObjectsAndKeys:
                                [UIFont systemFontOfSize:18],UITextAttributeFont,
                                [UIColor blackColor],UITextAttributeTextColor,
                                [UIColor whiteColor],UITextAttributeTextShadowColor,
                                [NSValue valueWithCGSize:CGSizeMake(1, 1)],UITextAttributeTextShadowOffset,nil];

 NSDictionary *textAttibutesSelected = [NSDictionary dictionaryWithObjectsAndKeys:
                                          [UIFont systemFontOfSize:18],UITextAttributeFont,
                                          [UIColor whiteColor],UITextAttributeTextColor,
                                          [UIColor whiteColor],UITextAttributeTextShadowColor,
                                          [NSValue valueWithCGSize:CGSizeMake(0, 0)],UITextAttributeTextShadowOffset,nil];

 [[UISegmentedControl appearance] setTitleTextAttributes:textAttibutesUnSelected
                                                forState:UIControlStateNormal];

 [[UISegmentedControl appearance] setTitleTextAttributes:textAttibutesSelected
                                                forState:UIControlStateSelected];