ios学习札记（三）UISlider与UISwitch控件

ios学习笔记（三）UISlider与UISwitch控件

1 首先我们还是创建一个Single View Application，然后打开MainStoryboard_iphone.storyboard,在IB中添加一个UISlider控件和一个Label，这个Label用来显示Slider的值。

选中新加的Slider控件，打开Attribute Inspector，修改属性值，设置最小值为0，最大值为100，当前值为0.5，并确保勾选上Continuous，如下图：

接着我们放上UISwitch控件，就是很像开关的那种控件，它只有两个状态：on和off，全都放上去效果就是这样的：

2.好了我们开始写代码喽：ViewController.h：

#import <UIKit/UIKit.h> @interface ViewController : UIViewController{ UILabel *sliderlabel; UISwitch *leftSwitch; UISwitch *rightSwitch; } @property (nonatomic,retain) IBOutlet UILabel *sliderlabel; @property (nonatomic,retain) IBOutlet UISwitch *leftSwitch; @property (nonatomic,retain) IBOutlet UISwitch *rightSwitch; - (IBAction)sliderChanged:(id)sender; - (IBAction)switchChanged:(id)sender; @end
接着是实现 ViewController.m:

#import "ViewController.h" @interface ViewController () @end @implementation ViewController @synthesize sliderlabel; @synthesize leftSwitch; @synthesize rightSwitch; - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. } - (void)viewDidUnload { [super viewDidUnload]; // Release any retained subviews of the main view. } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) { return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown); } else { return YES; } } - (IBAction)sliderChanged:(id)sender{ UISlider *slider=(UISlider*)sender; int progressAsInt=(int)(slider.value+0.5f); NSString *newText=[[NSString alloc] initWithFormat:@"%d",progressAsInt]; sliderlabel.text=newText; [newText release]; NSLog(@"%d",progressAsInt); } - (IBAction)switchChanged:(id)sender{ UISwitch *whichSwich=(UISwitch *)sender; BOOL setting=whichSwich.isOn; [leftSwitch setOn:setting animated:YES]; [rightSwitch setOn:setting animated:YES]; } - (void)dealloc{ [sliderlabel release]; [leftSwitch release]; [rightSwitch release]; [super dealloc]; } @end
3.剩下的就是连接操作和输出口：

将slider控件的value changed事件与sliderChanged方法连接在一起，将swich控件的value changed事件与swichChanged方法连接在一起，当然还要把lable控件和swich控件的输出与ViewController的相应控件接口连接在一起。

最终实现的效果如下面两张图：