iOS開發-View中frame和bounds區別

標籤：

開發中調整View的時候的經常會遇到frame和bounds，剛開始看的時候不是很清楚，不過看了一下官方文檔，frame是確定視圖在父視圖中的位置，和本身的大小,bounds確定可以確定子視圖在當前視圖中的位置，還可以改變View的大小，如果bounds確定大小，那麼View的視圖優先選擇的bounds中的寬高。Center的位置是相對於父座標系中的定位。蘋果官方給了一張圖片供參考:

如果還不是很清晰，可以參考一下frame和bounds的中代碼:

-(CGRect)frame{    return CGRectMake(self.frame.origin.x,self.frame.origin.y,self.frame.size.width,self.frame.size.height);}-(CGRect)bounds{    return CGRectMake(0,0,self.frame.size.width,self.frame.size.height);}

當然為了更好的理解以上的概念，寫個小Demo實戰了一下，viewDidLoad將圖片添加在View中，然後在圖片上添加一個View:

UIImageView  *girlImageView=[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"Girl.jpg"]];    girlImageView.frame=CGRectMake(40, 40, 240, 300);    [self.view addSubview:girlImageView];//添加到父視圖中    NSLog(@"girlImageView frame:%@------girlImageView bounds:%@",NSStringFromCGRect(girlImageView.frame),NSStringFromCGRect(girlImageView.bounds));    UIView *childView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];    childView.backgroundColor = [UIColor yellowColor];    [girlImageView addSubview:childView];    NSLog(@"childView frame:%@-------childView bounds:%@",NSStringFromCGRect(childView.frame),NSStringFromCGRect(childView.bounds));

　具體效果如下:

 

輸出結果:

2015-04-03 11:50:00.326 MyContraint[1929:98282] girlImageView frame:{{40, 40}, {240, 300}}------girlImageView bounds:{{0, 0}, {240, 300}}2015-04-03 11:50:00.327 MyContraint[1929:98282] childView frame:{{0, 0}, {100, 100}}-------childView bounds:{{0, 0}, {100, 100}}

　這個時候如果改變一下UIImageView的bounds，代碼如下:

   UIImageView  *girlImageView=[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"Girl.jpg"]];    girlImageView.frame=CGRectMake(40, 40, 240, 300);    //改變View中內部原點的位置，同樣可以改變frame的寬高    [girlImageView setBounds:CGRectMake(-30, -30, 240, 230)];    [self.view addSubview:girlImageView];//添加到父視圖中    NSLog(@"girlImageView frame:%@------girlImageView bounds:%@",NSStringFromCGRect(girlImageView.frame),NSStringFromCGRect(girlImageView.bounds));

　圖片效果:

列印效果如下:

2015-04-03 11:57:06.738 MyContraint[2019:102665] girlImageView frame:{{40, 75}, {240, 230}}------girlImageView bounds:{{-30, -30}, {240, 230}}2015-04-03 11:57:06.739 MyContraint[2019:102665] childView frame:{{0, 0}, {100, 100}}-------childView bounds:{{0, 0}, {100, 100}}

　通過以上的代碼的示範，frame和bounds之間的關係應該很清晰了，如果有疑問，歡飲共同探討~

iOS開發-View中frame和bounds區別