Iphone开发基础教程 example4

slider实现（必会）

1、在ViewController.xib文件中，从library中托出一个slider，一个label（并调整大小、文本）

2、在ViewController.h文件中，添加sliderLabel变量和它的@property方法，添加方法sliderChanged

#import <UIKit/UIKit.h>@interface ViewController : UIViewController{    IBOutlet UILabel *sliderLabel;}@property(retain,nonatomic) UILabel *sliderLabel;-(IBAction)sliderChanged:(id)sender;@end

3、在ViewController.m文件实现sliderChanged方法 及 @synthesize方法

#import "ViewController.h"@implementation ViewController@synthesize sliderLabel;-(IBAction)sliderChanged:(id)sender{    //NSLog(@"sliderChanged");    UISlider *slider = (UISlider *)sender;    int progressAsInt = (int)(slider.value);    NSString * newText = [[NSString alloc] initWithFormat:@"%d",progressAsInt];    sliderLabel.text = newText;    [newText release];}

4、回到xib文件中，Control键并从File‘s Owner拖动到标签，然后选择sliderLabel；

选中slider，打开connection，将value changed后的加号连接到File's Owner，选择sliderChanged

5、运行，看效果

在文本框输完字符后，点击Done，隐藏软键盘

1、头文件中，增加方法；在实现文件中，实现该方法

-(IBAction)textFieldDoneEditing:(id)sender;

-(IBAction)textFieldDoneEditing:(id)sender{    NSLog(@"textFieldDoneEditing");    [sender resignFirstResponder];}

2、xib文件中，选中文本框，打开connection 拖Did end on Exit后边的圆圈到File's Owner，选择textFieldDoneEditing

3、运行，看效果

按钮实现（必会）

1、在ViewController.xib文件中添加一个按钮

2、在ViewController.h文件中，

@property(retain,nonatomic) UIButton *doSomethingButton;

-(IBAction)doSomething:(id)sender;

3、在ViewController.m文件中，实现

@synthesize doSomethingButton;

-(IBAction)doSomething:(id)sender{    UIActionSheet *actionSheet = [[UIActionSheet alloc]                                  initWithTitle:@"Are you sure?"                                  delegate:self                                  cancelButtonTitle:@"No way" destructiveButtonTitle:@"Yes,I'm Sure" otherButtonTitles:nil];    [actionSheet showInView:self.view];    [actionSheet release];    }-(void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex{    if(!buttonIndex ==[actionSheet cancelButtonIndex])    {        NSString *msg = nil;        if(nameField.text.length>0)            msg = [[NSString alloc] initWithFormat:@"You can breathe easy,%@,everything went OK",nameField.text];        else            msg = @"You can breathe easy,everything went OK";        UIAlertView *alert = [[UIAlertView alloc]                              initWithTitle:@"Something was done"                               message:msg                              delegate:self                               cancelButtonTitle:@"Phew!"                               otherButtonTitles:nil];        [alert show];        [alert release];        [msg release];    }}

4、运行看效果