iOS-个人整理09 - UIControl与子类：UISlider，UISegmentControl

一、UISlider

UISlider是iOS中的滑块控件
通常用于控制视频播放进度，控制音量
它继承于UIControl，滑块位于滑条不同位置时提供不同的Value值

 //滑竿初始化  
 UISlider *mySlider = [[UISlider alloc]initWithFrame:CGRectMake(22, 22, 300, 50)];  
   
 //设置滑竿值范围  
 mySlider.minimumValue = 0.5;  
 mySlider.maximumValue = 3;  
 //设置起始值  
 mySlider.value = 1;  
   
 //设置滑过范围的颜色  
 mySlider.minimumTrackTintColor = [UIColor grayColor];  
 //未滑过的颜色  
 mySlider.maximumTrackTintColor = [UIColor redColor];  
   
 //指定左边和右边指示图 图像大小30X30  
 mySlider.minimumValueImage = [UIImage imageNamed:@"bc.jpg"];  
 mySlider.maximumValueImage = [UIImage imageNamed:@"bc.jpg"];  
 //设置滑块的颜色  
 mySlider.thumbTintColor = [UIColor greenColor];  
 mySlider.tag = 1004;  
  
 //设置滑块的图片  
 [mySlider setThumbImage: [UIImage imageNamed:@"bc.jpg"]forState:UIControlStateNormal];  
  
 //添加触发事件，滑动滑竿触发  
 [mySlider addTarget:self action:@selector(changeTransform:) forControlEvents:UIControlEventValueChanged];  
  
 //添加到父视图  
 [self.view addSubview:mySlider];  

可以练习创建三个UISlider，通过它们改变背景的RGB值，达到调节背景颜色的效果,没啥难度

二、UISegmentControl

UISegmentControl是iOS中常用的分段控件，它相当于集成了多个Button
可以使用分段控件切换不同的视图

//初始化，items 根据数组在的元素创建相应个数的按钮  
    UISegmentedControl *segmentedControl = [[UISegmentedControl alloc]initWithItems:[NSArray arrayWithObjects:@"红",@"绿",@"蓝", nil nil]];  
      
    //设置大小  
    segmentedControl.frame = CGRectMake(100, 100, 200, 50);  
      
    //指定被选中的分段  
    segmentedControl.selectedSegmentIndex = 0;  
    [segmentedControl setSelectedSegmentIndex:1];  
      
    //更改分段控制器颜色  
    [segmentedControl setTintColor:[UIColor grayColor]];  
      
    //给每个分段设置图片  
    //渲染模式imageWithRenderingMode 设置 为UIImageRenderingModeAlwaysOriginal  
    //否则会根据当前的颜色对图片进行颜色渲染  
    [segmentedControl setImage:[[UIImage imageNamed:@"bc.jpg"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forSegmentAtIndex:1];  
      
    //添加点击事件  
    [segmentedControl addTarget:self action:@selector(changeBgColor:) forControlEvents:UIControlEventValueChanged];  
      
    //设置样式，已经废弃  
   // segmentedControl.segmentedControlStyle  
      
     [self.view addSubview:segmentedControl];  

下面做一个小练习，通过UISegmentControl改变视图的颜色

#pragma mark  三个界面通过分段控制器切换  
      
    //创建三个视图  
    for (int i = 0; i < 3; i ++) {  
        UIView *view = [[UIView alloc]initWithFrame:CGRectMake(0, 300, 375, 300)];  
        view.tag = 1000+i;  
        //设置背景色为随机  
        view.backgroundColor = [UIColor colorWithRed:arc4random()%256/255.0 green:arc4random()%256/255.0 blue:arc4random()%256/255.0 alpha:1];  
        [self.view addSubview:view];  
//        if (i == 0) {  
//            view.hidden = NO;  
//        }  
//        else  
//            view.hidden = YES;  
    }  
      
    //创建分段控制器  
    UISegmentedControl *changeViewSegment = [[UISegmentedControl alloc]initWithItems:[NSArray arrayWithObjects:@"1",@"2",@"3", nil nil]];  
    changeViewSegment.frame = CGRectMake(80, 100, 200, 30);  
      
    //默认选中第一个分段，设置tag值  
    changeViewSegment.selectedSegmentIndex = 0;  
    changeViewSegment.tag = 1003;  
      
    //添加方法，点击分段切换颜色  
    [changeViewSegment addTarget:self action:@selector(changeView:) forControlEvents:UIControlEventValueChanged];  
    [self.view addSubview:changeViewSegment];  
  
//segment切换视图方法  
  
 -(void)changeView:(UISegmentedControl*)sender  
{  
    //根据Tag值得到三个视图  
    UIView *firstView = [self.view viewWithTag:1000];  
    UIView *secondView = [self.view viewWithTag:1001];  
    UIView *thirdView = [self.view viewWithTag:1002];  
      
    //通过修改三个视图的hidden属性实现切换  
    switch (sender.selectedSegmentIndex) {  
        case 0:  
            firstView.hidden = NO;  
            secondView.hidden = YES;  
            thirdView.hidden = YES;  
            break;  
        case 1:  
            firstView.hidden = YES;  
            secondView.hidden = NO;  
            thirdView.hidden = YES;  
            break;  
        case 2:  
            firstView.hidden = YES;  
            secondView.hidden = YES;  
            thirdView.hidden = NO;  
            break;  
        default:  
            break;  
    }  
}  
 
 
实现效果如下：