UISlider

位置，获取的值也是不同的。

//
//  ViewController.m
//  UISlider01
//
//  Created by cqy on 16/2/15.
//  Copyright © 2016年 程清杨. All rights reserved.
//

#import "ViewController.h"

@interface ViewController (){
    UISlider *slider;
}

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    //slider进度条
    //创建slider
    slider = [[UISlider alloc]initWithFrame:CGRectMake(50, 200, 200, 50)];
    //设置最?值 负数也可以
    slider.minimumValue = 0;
    //最大值
    slider.maximumValue = 1;
    //当前值
    slider.value = 0.5;
    //划过领域
    slider.minimumTrackTintColor = [UIColor greenColor];
    //未划过的领域
    slider.maximumTrackTintColor = [UIColor grayColor];
    //?圆点变颜?(进度条上当前位置?圆点的颜?（想要把?圆点的颜?改变，得?先把这个?圆点?图?来代替：调setThumbImage?法）)
    slider.thumbTintColor = [UIColor redColor];
    //设置图?后，?圆点才会变颜?
   // [slider setThumbImage:[UIImage imageNamed:@"slider"] forState:UIControlStateNormal];
    // 最?值图?
   // slider.minimumValueImage = [UIImage imageNamed:@"slider.png"];
    // 最?值图?
    //slider.maximumValueImage = [UIImage  imageNamed:@"slider02.png"];
    //添加滑动事件
    [slider addTarget:self action:@selector(sliderAction:) forControlEvents:UIControlEventValueChanged];
        [self.view addSubview:slider];
       // Do any additional setup after loading the view, typically from a nib.
}
- (void)sliderAction:(UISlider *)sender{
    NSLog(@"%lf",sender.value);
      // 使?slider的值，改变视图透明度sender.value:为当前值sender.value为当前值
    self.view.alpha = sender.value;
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end