建一个Single View Application的project。

部分代码：

#import 
     
       @interface BIDViewController : UIViewController @property (strong, nonatomic) IBOutlet UITextField *nameField; @property (strong, nonatomic) IBOutlet UITextField *numberField; - (IBAction)textFieldDoneEditing:(id)sender;//为了Done时退出键盘 - (IBAction)backgroundTap:(id)sender;//for 点背景退出键盘
     

- (IBAction)sliderChanged:(id)sender;

@end

- (IBAction)textFieldDoneEditing:(id)sender {
   [sender resignFirstResponder];//取消第一响应者的状态 }//Did End On Exit - (IBAction)backgroundTap:(id)sender {
   [nameField resignFirstResponder]; [numberField resignFirstResponder]; }//Touch down

  - (IBAction)sliderChanged:(id)sender {
     UISlider *slider = (UISlider *)sender;   int progressAsInt = (int)roundf(slider.value);   sliderLabel.text = [NSString stringWithFormat:@"%d", progressAsInt]；

  }//slider改变label的值

注意将View的Class改为UIControl，