UI 02 UIButton

UIButton 繼承於 UIControl , UIControl 繼承於 UIView.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor purpleColor];
    [self.window makeKeyAndVisible];
    [self.window release];


// 創建一個UIButton
UIButton *button = [UIButton buttonWithType:UIButtonTypeSystem];
    button.frame = CGRectMake(150, 100, 80, 80)
    ;
    button.backgroundColor = [UIColor whiteColor];
    [self.window addSubview:button];

    [button setTitle:@"確認" forState:UIControlStateNormal];
    button.titleLabel.font = [UIFont systemFontOfSize:25];

    button.layer.cornerRadius = 8;
    button.layer.masksToBounds = YES;
    [button addTarget:self action:@selector(changePic:) forControlEvents:UIControlEventTouchUpInside];
    button.tag = 1000;
    self.isSelected = YES;
    // 給Button設置背景圖片
    [button setBackgroundImage:[UIImage imageNamed:@"checked.png"] forState:UIControlStateNormal];

    UIButton  *buttontwo  = [UIButton buttonWithType:UIButtonTypeCustom];
    buttontwo.frame = CGRectMake(150, 220, 80, 80);
    [self.window addSubview:button1];


  //  buttontwo.layer.cornerRadius = 8;
 //   [buttontwo setTitle:@"測試" forState:UIControlStateNormal];
 //   buttontwo.titleLabel.font = [UIFont systemFontOfSize:10];
    [buttontwo addTarget:self action:@selector(changeImage:) forControlEvents:UIControlEventTouchUpInside];
    buttontwo.tag = 1001;

    // 設置前景圖片 
    [buttontwo setImage:[UIImage imageNamed:@"BtnOff.png"] forState:UIControlStateNormal];
    self.isClick = NO;


    return YES;
}



- (void)click:(UIButton *)button{
//誰觸發了按鈕,相應的button就是那個對象.

    // 1.不管按誰,只修改的是tag是1000按鈕的內容

    UIButton *but = (UIButton *)[self.window viewWithTag:1000];
    // 判斷當前按鈕的標題
    //currentTitle -- 獲取當前按鈕標題.

   if ([but.currentTitle compare:@"確認"] == 0) {
        [but setTitle:@"取消" forState:UIControlStateNormal];
    }else{
        [but setTitle:@"確認" forState:UIControlStateNormal];
 }
 // 打印出button當前的標題.
     NSLog(@"%@",but.currentTitle);


    //2.按哪個按鈕,哪個按鈕的內容就會改變
    if ([button.currentTitle isEqualToString:@"確認"]) {
       [button setTitle:@"取消" forState:UIControlStateNormal];
   }else{
        [button setTitle:@"確認" forState:UIControlStateNormal];
   }
    NSLog(@"%ld",button.tag);


定義一條 @property(nonatomic, assign)BOOL isSelected; 的屬性  
// 更換按鈕的背景圖方法.
- (void)changePic:(UIButton *)button{
    //判斷
    if (self.isSelected) {
        [button setBackgroundImage:[UIImage imageNamed:@"check.png"] forState:UIControlStateNormal];
    }else{
        [button setBackgroundImage:[UIImage imageNamed:@"checked.png"] forState:UIControlStateNormal];
    }
    // 最後別忘了把當前的狀態進行調整.
    self.isSelected = !self.isSelected;

    if ([button.currentTitle isEqualToString:@"確認"]) {
        [button setTitle:@"取消" forState:UIControlStateNormal];
    }else{
        [button setTitle:@"確認" forState:UIControlStateNormal];
    }    
}     
}



定義一條@property(nonatomic, assign)BOOL isClick;的屬性.
- (void)changeImage:(UIButton *)button{
    //更換前景圖片
    if (self.isClick) {
        [button setImage:[UIImage imageNamed:@"BtnOff.png"] forState:UIControlStateNormal];
    }else{
        [button setImage:[UIImage imageNamed:@"BtnOn.png"] forState:UIControlStateNormal];
    }
    self.isClick = !self.isClick;
}