uibutton與圖像

Question

我有一個使用IB的按鈕。 現在我想以編程方式向按鈕添加圖像。 如何設置按鈕的圖像尺寸大小，就像我們在IB布局 - >尺寸適合中一樣。 我想以編程方式進行

謝謝..

Answer 1

您可以使用UIButton的setImage:forState:方法將圖像添加到按鈕，然后使用UIView的contentMode屬性設置內容大小。

一個例子看起來像這樣：

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
UIImage *img = [UIImage imageNamed:@"myImage.png"];

button.frame = CGRectMake(20, 100, img.size.width, img.size.height);

[button setImage:img forState:UIControlStateNormal];
[button setImage:img forState:UIControlStateHighlighted];
[button setImage:img forState:UIControlStateSelected];

button.contentMode = UIViewContentModeScaleToFill; //Look up UIViewContentMode in the documentation for other options

[self.view addSubview:button];

Answer 2

[yourButton setImage:yourImage forState:UIControlStateNormal];
yourButton.contentMode = UIViewContentModeScaleToFill;

其中contentMode的值可以是以下任何一個

typedef enum {
    UIViewContentModeScaleToFill,
    UIViewContentModeScaleAspectFit,      // contents scaled to fit with fixed aspect. remainder is transparent
    UIViewContentModeScaleAspectFill,     // contents scaled to fill with fixed aspect. some portion of content may be clipped.
    UIViewContentModeRedraw,              // redraw on bounds change (calls -setNeedsDisplay)
    UIViewContentModeCenter,              // contents remain same size. positioned adjusted.
    UIViewContentModeTop,
    UIViewContentModeBottom,
    UIViewContentModeLeft,
    UIViewContentModeRight,
    UIViewContentModeTopLeft,
    UIViewContentModeTopRight,
    UIViewContentModeBottomLeft,
    UIViewContentModeBottomRight,
} UIViewContentMode;

我想這可以幫到你

Answer 3

示例代碼，

UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
UIImage *img1 = [UIImage imageNamed:@"image1.png"];
btn.frame = CGRectMake(20.0 , 270.0, img1.size.width, img1.size.height);
[btn setImage:img1 forState:UIControlStateNormal]; 
UIImage *img2 = [UIImage imageNamed:@"image2.png"];
[btn setImage:img2 forState:UIControlStateHighlighted];
[btn setImage:img2 forState:UIControlStateSelected];
[btn addTarget:self action:@selector(Action:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:btn];

Answer 4

使用UIButton的sizeToFit方法（實際上是UIView）。