我想在用户点击 PNG 时为其着色。
我在 Xcode 中找到了一个例子 here但是当我在 C# 中尝试时,我无法检索图像。
这是我写的代码:
public UIImage DrawSelectedBorder(UIImage image)
{
UIGraphics.BeginImageContextWithOptions(image.Size, false, image.CurrentScale); // for correct resolution on retina, thanks @MobileVet
CGContext context = UIGraphics.GetCurrentContext();
context.TranslateCTM(0, image.Size.Height);
context.ScaleCTM((System.nfloat)1.0, (System.nfloat)(-1.0));
CGRect rect = new CGRect(0, 0, image.Size.Width, image.Size.Height);
context.SetBlendMode(CGBlendMode.Normal);
context.SetFillColor(UIColor.Black.CGColor);
context.FillRect(rect);
// draw original image
context.SetBlendMode(CGBlendMode.Normal);
context.DrawImage(rect,image.CGImage);
// tint image (losing alpha) - the luminosity of the original image is preserved
context.SetBlendMode(CGBlendMode.Color);
context.FillRect(rect);
// mask by alpha values of original image
context.SetBlendMode(CGBlendMode.DestinationIn);
context.DrawImage(rect, image.CGImage);
UIImage coloredImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return coloredImage;
}
最佳答案
刚试过你的代码。一切正常,但您没有选择要填充到 PNG 中的颜色。
改变:
// tint image (losing alpha) - the luminosity of the original image is preserved
context.SetBlendMode(CGBlendMode.Color);
context.FillRect(rect);
到:
// tint image (losing alpha) - the luminosity of the original image is preserved
context.SetBlendMode(CGBlendMode.Color);
context.SetFillColor(UIColor.Red.CGColor);
context.FillRect(rect);
关于c# - UIImage PNG着色,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/43408862/