我有两个按钮。它们都有相同的图像,只是其中一张图像被翻转了。如果可以以编程方式创建图像,我不想在我的应用程序包中包含多余的图像,因此我创建了如下按钮:
UIImage *forwardImage = [UIImage imageNamed:rewind_btn_img];
UIImage *rewindImage = [UIImage imageWithCGImage:forwardImage.CGImage
scale:forwardImage.scale
orientation:UIImageOrientationUpMirrored];
NSArray *images = @[rewindImage, forwardImage];
for (int i = 0; i < 2; i++)
{
UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
UIImage *image = images[i];
btn.frame = CGRectMake(0.f, 0.f, image.size.width, image.size.height);
btn.center = CGPointMake(self.playButton.center.x + (i == 0 ? - 80.f : 80.f) * TGScaleMultiplier, self.playButton.center.y);
btn.tag = i + 1;
[btn setBackgroundImage:image forState:UIControlStateNormal];
[btn addTarget:self action:@selector(rewindButtonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:btn];
}
问题是,当我按下图像为 rewindImage
的按钮时,它会显示原始图像,翻转到另一侧。我在这里做错了什么吗?有什么解决办法吗?
最佳答案
不确定为什么 UIImage:imageWithCGImage 不稳定,但我尝试了另一种镜像图像的方法,当应用于按钮时效果很好。因此,摆脱 UIImage:imageWithCGImage 行并使用它:
UIImage *rewindImageBase = [UIImage imageNamed:rewind_btn_img];
UIGraphicsBeginImageContext(rewindImageBase.size);
CGContextRef current_context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(current_context, rewindImageBase.size.width, 0);
CGContextScaleCTM(current_context, -1.0, 1.0);
[rewindImageBase drawInRect:CGRectMake(0, 0, rewindImageBase.size.width, rewindImageBase.size.height)];
UIImage *rewindImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
应该可以了。
关于ios - UIButton 在突出显示状态下更改代码中创建的图像,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/24615115/