藍色矩形UIStepper自定義結果

Question

我一直在嘗試自定義通過Interface Builder添加的對象UIStepper的外觀。關於主題here和其他人，我已經添加了幾行代碼到viewDidLoad。

- (void)viewDidLoad { 
    [[UIStepper appearance] setIncrementImage:[UIImage imageNamed:@"stepperupImage.tif"] forState:UIControlStateNormal]; 
    [[UIStepper appearance] setDecrementImage:[UIImage imageNamed:@"stepperdownImage.tif"] forState:UIControlStateNormal]; 
} 

結果是藍色的死亡矩形如下所示。 UIStepper對於UIButton沒有像UIButtonTypeCustom這樣的屬性。有誰知道如何解決這個問題？我的部署目標是iOS 8.0。

謝謝。

Answer 1

爲了使不具備透明度和最初的圖像，無論是：

• 更改「渲染爲」設置爲「原始圖像」 ^{（.xcasset文件只）}：
  

- 或 -

• 更改渲染模式，代碼(docs)：

  UIImage *image; 
  image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]; 
  

在你的情況下，代碼應該是這樣的：

[[UIStepper appearance] setIncrementImage:[[UIImage imageNamed:@"stepperupImage.tif"] imageWithRenderingMode: UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal]; 
[[UIStepper appearance] setDecrementImage:[[UIImage imageNamed:@"stepperdownImage.tif"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal]; 

Answer 2

UIImage *incrementImageFromFile = [UIImage imageNamed:@"plus.png"]; 
UIImage *incrementImage = [incrementImageFromFile imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]; 

UIImage *decrementImageFromFile = [UIImage imageNamed:@"minus.png"]; 
UIImage *decrementImage = [decrementImageFromFile imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]; 



// For Normal state 
[stepper setIncrementImage:incrementImage forState:UIControlStateNormal]; 
[stepper setDecrementImage:decrementImage forState:UIControlStateNormal]; 

// For Highlighted state 
[stepper setIncrementImage:incrementImage forState:UIControlStateHighlighted]; 
[stepper setDecrementImage:decrementImage forState:UIControlStateHighlighted];