在做歌詞的時候,有時候歌詞顔色會發生變化 ,一般會用UIImage做剪裁,慢慢出現不同的顔色,用UIlable專為UIImage,圖檔進行繪圖操作就可以達到想要的效果了
label轉化成image:
- (UIImage*) imageWithUIView:(UIView*) view
{
UIGraphicsBeginImageContext(view.bounds.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[view.layer renderInContext:ctx];
UIImage* tImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return tImage;
}
然後進行繪圖剪裁
- (UIImage *)croppedImage:(UIImage *)image cutRect:(NSInteger)width
{
if (image)
{
float min = MIN(image.size.width,image.size.height);
CGRect rectMAX = CGRectMake(0, 0, width, min);
CGImageRef subImageRef = CGImageCreateWithImageInRect(image.CGImage, rectMAX);
UIGraphicsBeginImageContext(rectMAX.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextDrawImage(context, CGRectMake(0, 0, width, min), subImageRef);
UIImage *viewImage = [UIImage imageWithCGImage:subImageRef];
UIGraphicsEndImageContext();
CGImageRelease(subImageRef);
return viewImage;
}
return nil;
}
這樣就可以根據時間出現緩慢的出現歌詞了。。。。。。