xcode 设置 UIButton 图像并保持透明度
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Set UIButton image and maintain transparency
提问by Glib
I have a UIButton (set to type "Custom"). If I set the image in Interface Builder, the image is shown properly, with transparency. But if I try to set it programmatically while the App is running (for example, to change the image displayed on the button), the transparency isn't displayed correctly - instead I get a white background to the image.
我有一个 UIButton（设置为“自定义”类型）。如果我在 Interface Builder 中设置图像，图像会正确显示，具有透明度。但是，如果我尝试在应用程序运行时以编程方式设置它（例如，更改按钮上显示的图像），则透明度无法正确显示 - 而是图像的白色背景。
This is how I'm setting the button's image in code:
这就是我在代码中设置按钮图像的方式：
[die1Button setImage:[UIImage imageNamed:die1.dieImage] forState:UIControlStateNormal];
Would hugely appreciate any ideas.
非常感谢任何想法。
采纳答案by Glib
Xcode was remembering the previous version of the images, the ones without transparency - even though I had added the new versions with transparency. I had to do a Product - Clean and now it's all as expected.
Xcode 正在记住图像的先前版本，即没有透明度的图像 - 即使我添加了具有透明度的新版本。我不得不做一个产品 - 清洁，现在一切都如预期的那样。
回答by devsri
The method you are using puts the image on the foreground of the button. I used the following method and it worked
您正在使用的方法将图像放在按钮的前景。我使用了以下方法并且它有效
[die1Button setBackgroundImage:[UIImage imageNamed:@"yourImageName.png"] forState:UIControlStateNormal];
Hope this works for you as well... :)
希望这也适用于你...... :)
