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