Ios UIButton-仅在一个方向上可拉伸的背景图像？

我有一个UIButton对象，其中我使用一个可拉伸的图像作为背景，因此我可以始终具有灵活的按钮大小

问题是我希望图像有一个固定的高度（比如32px），但我希望有一个更高的可触摸区域（苹果用户界面指南总是说至少44px高）

如果我在x中有一个可拉伸的图像，不幸的是它也在y中拉伸。我想告诉图像不要在y方向拉伸。这可能吗

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[编辑]是的。回答我自己的问题：

所以，为了帮助别人，我可以回答我自己的问题：

@interface StretchableXButton : UIButton
{
    CGFloat imageHeight;
}
@property CGFloat imageHeight;  // we need this later when we override an instance method

+ (id)buttonWithFrame:(CGRect)frame;

@end

现在实施：

@implementation StretchableXButton
@synthesize imageHeight; 

+ (id)buttonWithFrame:(CGRect)frame
{
    StretchableXButton *button = [super buttonWithType:UIButtonTypeCustom];

    UIImage *normalImage = [UIImage imageNamed: @"ButtonBGNormal.png" ];
    UIImage *highlightedImage = [UIImage imageNamed:@"ButtonBGHighlighted.png" ];

    button.frame = frame;
    button.imageHeight = normalImage.size.height;  // we need him later in the method below

    // make the images stretchable
    normalImage = [normalImage stretchableImageWithLeftCapWidth:normalImage.size.width/2 topCapHeight:normalImage.size.height/2];
    highlightedImage = [highlightedImage stretchableImageWithLeftCapWidth:normalImage.size.width/2 topCapHeight:normalImage.size.height/2];

    button.backgroundColor = [UIColor clearColor];

    // SET OTHER BUTTON PROPERTIES HERE (textLabel, fonts, etc.)

    [button setBackgroundImage:normalImage forState:UIControlStateNormal];
    [button setBackgroundImage:highlightedImage forState:UIControlStateHighlighted];

    return  button;
}

// THIS IS THE TRICK.  We make the height of the background rect match the image.
-(CGRect)backgroundRectForBounds:(CGRect)bounds
{
    CGRect bgRect = bounds;
    bgRect.origin.y = (bounds.size.height - imageHeight)/2.0f;
    bgRect.size.height = imageHeight;

    return bgRect;
}


@end

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因此，为了帮助他人，我可以回答自己的问题：

@interface StretchableXButton : UIButton
{
    CGFloat imageHeight;
}
@property CGFloat imageHeight;  // we need this later when we override an instance method

+ (id)buttonWithFrame:(CGRect)frame;

@end

现在实施：

@implementation StretchableXButton
@synthesize imageHeight; 

+ (id)buttonWithFrame:(CGRect)frame
{
    StretchableXButton *button = [super buttonWithType:UIButtonTypeCustom];

    UIImage *normalImage = [UIImage imageNamed: @"ButtonBGNormal.png" ];
    UIImage *highlightedImage = [UIImage imageNamed:@"ButtonBGHighlighted.png" ];

    button.frame = frame;
    button.imageHeight = normalImage.size.height;  // we need him later in the method below

    // make the images stretchable
    normalImage = [normalImage stretchableImageWithLeftCapWidth:normalImage.size.width/2 topCapHeight:normalImage.size.height/2];
    highlightedImage = [highlightedImage stretchableImageWithLeftCapWidth:normalImage.size.width/2 topCapHeight:normalImage.size.height/2];

    button.backgroundColor = [UIColor clearColor];

    // SET OTHER BUTTON PROPERTIES HERE (textLabel, fonts, etc.)

    [button setBackgroundImage:normalImage forState:UIControlStateNormal];
    [button setBackgroundImage:highlightedImage forState:UIControlStateHighlighted];

    return  button;
}

// THIS IS THE TRICK.  We make the height of the background rect match the image.
-(CGRect)backgroundRectForBounds:(CGRect)bounds
{
    CGRect bgRect = bounds;
    bgRect.origin.y = (bounds.size.height - imageHeight)/2.0f;
    bgRect.size.height = imageHeight;

    return bgRect;
}


@end

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以答案的形式回答自己的问题，而不是对问题进行编辑。你甚至可以这样接受。把你自己的问题作为答案回答，而不是对问题的编辑。你甚至可以这样接受。