public static UIImage Tint(this UIImage img, UIColor tint, CGBlendMode blendMode)
{
UIGraphics.BeginImageContextWithOptions(img.Size, false, 0f);
tint.SetFill();
var bounds = new CGRect(0, 0, img.Size.Width, img.Size.Height);
UIGraphics.RectFill(bounds);
img.Draw(bounds, blendMode, 1f);
if (blendMode != CGBlendMode.DestinationIn)
{
img.Draw(bounds, CGBlendMode.DestinationIn, 1f);
}
var tintedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(tintedImage);
}
/// <summary>
/// Resizes an image.
/// </summary>
/// <returns>The resized image.</returns>
/// <param name="originalImage">Original image.</param>
/// <param name="newHeight">New height.</param>
/// <param name="newWidth">New width.</param>
/// <param name="imageFormat">Image format Jpg or Png.</param>
public async Task <byte[]> ResizeImageAsync(byte[] originalImage, int newHeight, int newWidth, ImageFormat imageFormat)
{
byte[] resulImage = null;
UIKit.UIImage uiImage = await originalImage.ToImageAsync();
UIGraphics.BeginImageContext(new CoreGraphics.CGSize(newWidth, newHeight));
uiImage.Draw(new CoreGraphics.CGRect(0, 0, newWidth, newHeight));
UIImage resultUIImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
if (imageFormat == ImageFormat.JPG)
{
resulImage = resultUIImage.AsJPEG().ToArray();
}
else
{
resulImage = resultUIImage.AsPNG().ToArray();
}
return(resulImage);
}
static UIImage CreateBubbleWithBorder(UIImage bubbleImg, UIColor bubbleColor, UIImage borderImg, UIColor borderColor)
{
bubbleImg = CreateColoredImage(bubbleColor, bubbleImg);
borderImg = CreateColoredImage(borderColor, borderImg);
CGSize size = bubbleImg.Size;
UIEdgeInsets caps = CenterPointEdgeInsetsForImageSize(size);
UIGraphics.BeginImageContextWithOptions(size, false, 0);
var rect = new CGRect(CGPoint.Empty, size);
bubbleImg.Draw(rect);
borderImg.Draw(rect);
var result = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
result = result.CreateResizableImage(caps);
return(result);
}
private void SetGradientBackground()
{
if (NavigationController != null)
{
Color startColor = Color.FromHex("#19769f");
Color endColor = Color.FromHex("#35d8a6");
var gradientLayer = new CAGradientLayer();
gradientLayer.Bounds = NavigationController.NavigationBar.Bounds;
gradientLayer.Colors = new CGColor[] { startColor.ToCGColor(), endColor.ToCGColor() };
gradientLayer.StartPoint = new CGPoint(0.0, 0.5);
gradientLayer.EndPoint = new CGPoint(1.0, 0.5);
UIGraphics.BeginImageContext(gradientLayer.Bounds.Size);
gradientLayer.RenderInContext(UIGraphics.GetCurrentContext());
UIImage image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
NavigationController.NavigationBar.SetBackgroundImage(image, UIBarMetrics.Default);
}
}
public static UIImage MaxResizeImage(UIImage sourceImage, float maxWidth, float maxHeight)
{
var sourceSize = sourceImage.Size;
var maxResizeFactor = Math.Max(maxWidth / sourceSize.Width, maxHeight / sourceSize.Height);
if (maxResizeFactor > 1)
{
return(sourceImage);
}
var width = maxResizeFactor * sourceSize.Width;
var height = maxResizeFactor * sourceSize.Height;
UIGraphics.BeginImageContext(new SizeF((float)width, (float)height));
sourceImage.Draw(new RectangleF(0, 0, (float)width, (float)height));
var resultImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(resultImage);
}
public byte[] ResizeImage(string filename, float width, float height)
{
if (File.Exists(filename))
{
byte[] imageData = File.ReadAllBytes(filename);
UIImage originalImage = ImageFromByteArray(imageData);
var originalHeight = originalImage.Size.Height;
var originalWidth = originalImage.Size.Width;
nfloat newHeight = 0;
nfloat newWidth = 0;
if (originalHeight > originalWidth)
{
newHeight = height;
nfloat ratio = originalHeight / height;
newWidth = originalWidth / ratio;
}
else
{
newWidth = width;
nfloat ratio = originalWidth / width;
newHeight = originalHeight / ratio;
}
width = (float)newWidth;
height = (float)newHeight;
UIGraphics.BeginImageContext(new SizeF(width, height));
originalImage.Draw(new RectangleF(0, 0, width, height));
var resizedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
var bytesImagen = resizedImage.AsJPEG().ToArray();
resizedImage.Dispose();
return(bytesImagen);
}
return(null);
}
void Crop()
{
UIGraphics.BeginImageContextWithOptions(new CGSize(App.ScreenWidth, App.ScreenHeight), true, 1.0f);
startImage.Draw(new CGRect(imageViewToMove.ImgX, imageViewToMove.ImgY + center, imageViewToMove.ImgW, height));
resultImage = UIGraphics.GetImageFromCurrentImageContext();
var inputCGImage = resultImage.CGImage;
var image = inputCGImage.WithImageInRect(cropperView.CropRect);
using (var croppedImage = UIImage.FromImage(image))
{
//scretching the size of the cropped View
if (croppedImage.Size.Height < 968)
{
var testh = croppedImage.Size.Height;
var testw = croppedImage.Size.Width;
UIGraphics.BeginImageContextWithOptions(new CGSize(968, 968), true, 1.0f);
croppedImage.Draw(new CGRect(0, 0, 968, 968));
resultImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
var testh1 = resultImage.Size.Height;
var testw1 = resultImage.Size.Width;
using (NSData imageData = resultImage.AsPNG())
{
Byte[] myByteArray = new Byte[imageData.Length];
System.Runtime.InteropServices.Marshal.Copy(imageData.Bytes, myByteArray, 0, Convert.ToInt32(imageData.Length));
new ImageDoneCropping(myByteArray);
}
} //EndScretching
else
{
using (NSData imageData = croppedImage.AsPNG())
{
Byte[] myByteArray = new Byte[imageData.Length];
System.Runtime.InteropServices.Marshal.Copy(imageData.Bytes, myByteArray, 0, Convert.ToInt32(imageData.Length));
new ImageDoneCropping(myByteArray);
}
}
}
}
//
#if __IOS__
public static byte[] ResizeImageIOS(byte[] imageData, float width, float height)
{
// Load the bitmap
UIImage originalImage = ImageFromByteArray(imageData);
//
var Hoehe = originalImage.Size.Height;
var Breite = originalImage.Size.Width;
//
nfloat ZielHoehe = 0;
nfloat ZielBreite = 0;
//
if (Hoehe > Breite) // Höhe (71 für Avatar) ist Master
{
ZielHoehe = height;
nfloat teiler = Hoehe / height;
ZielBreite = Breite / teiler;
}
else // Breite (61 for Avatar) ist Master
{
ZielBreite = width;
nfloat teiler = Breite / width;
ZielHoehe = Hoehe / teiler;
}
//
width = (float)ZielBreite;
height = (float)ZielHoehe;
//
UIGraphics.BeginImageContext(new SizeF(width, height));
originalImage.Draw(new RectangleF(0, 0, width, height));
var resizedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
//
var bytesImagen = resizedImage.AsJPEG().ToArray();
resizedImage.Dispose();
return(bytesImagen);
}
public UIImage GetPDFImageForPage()
{
CGPDFPage pdfPg = _pdf.GetPage(PageNumber);
nfloat scale;
PDFpageRect = pdfPg.GetBoxRect(CGPDFBox.Media);
if (PDFpageRect.Height > PDFpageRect.Width)
{
scale = (this.View.Frame.Width - 80.0f) / PDFpageRect.Width;
}
else
{
scale = this.View.Frame.Height / PDFpageRect.Height;
}
PDFpageRect.Size = new CGSize(PDFpageRect.Width * scale, PDFpageRect.Height * scale);
UIGraphics.BeginImageContext(PDFpageRect.Size);
CGContext context = UIGraphics.GetCurrentContext();
context.SetFillColor((nfloat)1.0, (nfloat)1.0, (nfloat)1.0, (nfloat)1.0);
context.FillRect(PDFpageRect);
context.SaveState();
context.TranslateCTM(0, PDFpageRect.Size.Height);
context.ScaleCTM(1, -1);
context.ConcatCTM(CGAffineTransform.MakeScale(scale, scale));
context.DrawPDFPage(pdfPg);
context.RestoreState();
UIImage thm = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(thm);
}
public byte[] ResizeImage(byte[] imageData, float width, float height)
{
UIImage originalImage = ImageFromByteArray(imageData);
var originalImageHeight = originalImage.Size.Height;
var originalImageWidth = originalImage.Size.Width;
nfloat newHeight = 0;
nfloat newWidth = 0;
if (originalImageHeight > originalImageWidth)
{
newHeight = height;
nfloat scale = originalImageHeight / height;
newWidth = originalImageWidth / scale;
}
else
{
newWidth = width;
nfloat scale = originalImageWidth / width;
newHeight = originalImageHeight / scale;
}
width = (float)newWidth;
height = (float)newHeight;
UIGraphics.BeginImageContext(new SizeF(width, height));
originalImage.Draw(new RectangleF(0, 0, width, height));
var resizedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
var bytesImagen = resizedImage.AsJPEG().ToArray();
resizedImage.Dispose();
return(bytesImagen);
}
public static UIImage ImageFromFont(string text, UIColor iconColor, CGSize iconSize, string fontName = "ionicons")
{
UIGraphics.BeginImageContextWithOptions(iconSize, false, 0);
var textRect = new CGRect(CGPoint.Empty, iconSize);
var path = UIBezierPath.FromRect(textRect);
UIColor.Clear.SetFill();
path.Fill();
var font = UIFont.FromName(fontName, iconSize.Width);
using (var label = new UILabel()
{
Text = text, Font = font
})
{
GetFontSize(label, iconSize, 500, 5);
font = label.Font;
}
iconColor.SetFill();
using (var nativeString = new NSString(text))
{
nativeString.DrawString(textRect, new UIStringAttributes
{
Font = font,
ForegroundColor = iconColor,
BackgroundColor = UIColor.Clear,
ParagraphStyle = new NSMutableParagraphStyle
{
Alignment = UITextAlignment.Center
}
});
}
var image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(image);
}
/// <summary>
/// Gets the scaled image while maintaining correct aspect ration and not blurring.
///
/// See iOS code version at https://gist.github.com/tomasbasham/10533743
/// </summary>
/// <returns>The scaled image.</returns>
/// <param name="originalImage">Original image.</param>
UIImage GetScaledImage(UIImage originalImage)
{
CGSize newSize = new CGSize(originalImage.Size.Width / SCALING_FACTOR, originalImage.Size.Height / SCALING_FACTOR);
CGRect scaledImageRect = CGRect.Empty;
double aspectWidth = newSize.Width / originalImage.Size.Width;
double aspectHeight = newSize.Height / originalImage.Size.Height;
double aspectRatio = Math.Min(aspectWidth, aspectHeight);
scaledImageRect.Size = new CGSize(originalImage.Size.Width * aspectRatio, originalImage.Size.Height * aspectRatio);
scaledImageRect.X = (newSize.Width - scaledImageRect.Size.Width) / 2.0f;
scaledImageRect.Y = (newSize.Height - scaledImageRect.Size.Height) / 2.0f;
UIGraphics.BeginImageContextWithOptions(newSize, false, 0);
originalImage.Draw(scaledImageRect);
UIImage scaledImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(scaledImage);
}
public override UIImage GenerateBackgroundImage()
{
UIImage resultImage;
var center = new CGPoint(BackBounds.GetMidX(), BackBounds.GetMidY());
UIGraphics.BeginImageContextWithOptions(BackBounds.Size, false, UIScreen.MainScreen.Scale);
using (var context = UIGraphics.GetCurrentContext())
using (var borderBagelPath = BezierPathGenerator.Bagel(center, startRadius - borderPadding, endRadius + borderPadding, 0f, FullCircleAngle))
{
context.SaveState();
context.SetFillColor(BackCircleBackgroundColor);
borderBagelPath.Fill();
context.RestoreState();
resultImage = UIGraphics.GetImageFromCurrentImageContext();
}
return(resultImage);
}
private byte[] Resize(UIImage sourceImage, float percent, float quality)
{
UIImage resultImage;
var sourceSize = sourceImage.Size;
var width = percent * sourceSize.Width;
var height = percent * sourceSize.Height;
UIGraphics.BeginImageContext(new CGSize(width, height));
sourceImage.Draw(new CGRect(0, 0, width, height));
resultImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
using (var imageData = resultImage.AsJPEG(quality))
{
var res = new byte[imageData.Length];
Marshal.Copy(imageData.Bytes, res, 0, (int)imageData.Length);
return(res);
}
}
public byte[] Capture(View formsView)
{
if (formsView.Bounds.Width <= 0)
{
return(new byte[0]);
}
var nativeView = ConvertFormsToNative(formsView, formsView.Bounds);
UIGraphics.BeginImageContext(nativeView.Frame.Size);
nativeView.DrawViewHierarchy(nativeView.Frame, true);
var image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
using (var imageData = image.AsPNG())
{
var bytes = new byte[imageData.Length];
System.Runtime.InteropServices.Marshal.Copy(imageData.Bytes, bytes, 0, Convert.ToInt32(imageData.Length));
return(bytes);
}
}
private void SetupIcon()
{
if (_withIcon)
{
using (var image = UIImage.FromFile(_materialButton.Image.File))
{
UIGraphics.BeginImageContextWithOptions(new CGSize(18, 18), false, 0f);
image.Draw(new CGRect(0, 0, 18, 18));
using (var newImage = UIGraphics.GetImageFromCurrentImageContext())
{
UIGraphics.EndImageContext();
this.Control.SetImage(newImage, UIControlState.Normal);
this.Control.SetImage(newImage, UIControlState.Disabled);
this.Control.TitleEdgeInsets = new UIEdgeInsets(0f, 0f, 0f, 0f);
this.Control.ImageEdgeInsets = new UIEdgeInsets(0f, -6f, 0f, 0f);
this.Control.TintColor = _materialButton.TextColor.ToUIColor();
}
}
}
}
void DrawLine(CGPoint pt1, CGPoint pt2, UIColor color)
{
UIGraphics.BeginImageContext(imgDraw.Frame.Size);
using (var g = UIGraphics.GetCurrentContext())
{
imgDraw.Layer.RenderInContext(g);
using (var path = new CGPath())
{
path.AddLines(new CGPoint [] { pt1, pt2 });
g.SetLineWidth(3);
color.SetStroke();
g.AddPath(path);
g.DrawPath(CGPathDrawingMode.Stroke);
}
imgDraw.Image?.Dispose();
imgDraw.Image = UIGraphics.GetImageFromCurrentImageContext();
}
UIGraphics.EndImageContext();
}
public UIImage GetImageFromView()
{
RectangleF rect;
rect = (RectangleF)Frame;
UIGraphics.BeginImageContext(rect.Size);
CGContext context = UIGraphics.GetCurrentContext();
if (_image != null)
{
context.DrawImage(Frame, _image.CGImage);
}
this.Layer.RenderInContext(context);
UIImage image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(image);
}
void DrawLine(CGPoint fromPoint, CGPoint toPoint)
{
UIGraphics.BeginImageContextWithOptions(ImgSample.Frame.Size, false, 0);
var context = UIGraphics.GetCurrentContext();
context.MoveTo(fromPoint.X, fromPoint.Y);
context.AddLineToPoint(toPoint.X, toPoint.Y);
context.SetLineCap(CGLineCap.Round);
context.SetBlendMode(CGBlendMode.Normal);
context.SetLineWidth(10);
context.SetStrokeColor(UIColor.Red.CGColor);
ImgSample.Image.Draw(new CGRect(0, 0, ImgSample.Frame.Size.Width, ImgSample.Frame.Size.Height));
context.StrokePath();
var newImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
ImgSample.Image = newImage;
}
//Crops an image to even width and height
private static UIImage CenterCrop(UIImage originalImage)
{
// Use smallest side length as crop square length
double squareLength = Math.Min(originalImage.Size.Width, originalImage.Size.Height);
nfloat x, y;
x = ( nfloat )((originalImage.Size.Width - squareLength) / 2.0);
y = ( nfloat )((originalImage.Size.Height - squareLength) / 2.0);
//This Rect defines the coordinates to be used for the crop
CGRect croppedRect = CGRect.FromLTRB(x, y, x + ( nfloat )squareLength, y + ( nfloat )squareLength);
// Center-Crop the image
UIGraphics.BeginImageContextWithOptions(croppedRect.Size, false, originalImage.CurrentScale);
originalImage.Draw(new CGPoint(-croppedRect.X, -croppedRect.Y));
UIImage croppedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(croppedImage);
}
protected override void OnElementChanged(VisualElementChangedEventArgs e)
{
base.OnElementChanged(e);
if (e.OldElement != null || Element == null)
{
return;
}
ContentPage page = (ContentPage)Element;
// define SafeArea
page.On <Xamarin.Forms.PlatformConfiguration.iOS>().SetUseSafeArea(true);
if (!string.IsNullOrEmpty(page.BackgroundImage))
{
UIImage ImageBackground = UIImage.FromFile(page.BackgroundImage);
page.BackgroundImage = null;
CGRect scaledImageRect = CGRect.Empty;
double aspectWidth = this.View.Frame.Size.Width / ImageBackground.Size.Width;
double aspectHeight = this.View.Frame.Size.Height / ImageBackground.Size.Height;
double aspectRatio = Math.Max(aspectWidth, aspectHeight);
scaledImageRect.Size = new CGSize(ImageBackground.Size.Width * aspectRatio, ImageBackground.Size.Height * aspectRatio);
scaledImageRect.X = (this.View.Frame.Size.Width - scaledImageRect.Size.Width) / 2.0f;
scaledImageRect.Y = (this.View.Frame.Size.Height - scaledImageRect.Size.Height) / 2.0f;
UIGraphics.BeginImageContextWithOptions(this.View.Frame.Size, false, 0);
ImageBackground.Draw(scaledImageRect);
UIImage scaledImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
this.View.BackgroundColor = UIColor.FromPatternImage(scaledImage);
}
}
public static UIImage RemoveSharpEdges(this UIImage image, int radius)
{
var width = image.Size.Width;
UIGraphics.BeginImageContextWithOptions(new SizeF(width, width), false, 0f);
var context = UIGraphics.GetCurrentContext();
context.BeginPath();
context.MoveTo(width, width / 2);
context.AddArcToPoint(width, width, width / 2, width, radius);
context.AddArcToPoint(0, width, 0, width / 2, radius);
context.AddArcToPoint(0, 0, width / 2, 0, radius);
context.AddArcToPoint(width, 0, width, width / 2, radius);
context.ClosePath();
context.Clip();
image.Draw(new PointF(0, 0));
var converted = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(converted);
}
// Mashes up the images.
private UIImage ImageFromImages(List <UIImage> images, CGSize size)
{
if (images.Count <= 1)
{
return(images.FirstOrDefault());
}
UIGraphics.BeginImageContextWithOptions(size, true, 0);
if (images.Count == 2 || images.Count == 3)
{
// Draw left half.
images[0].Draw(new CGRect(-size.Width / 4, 0, size.Width, size.Height));
}
if (images.Count == 2)
{
// Draw right half.
UIImage halfOfImage = HalfOfImage(images[1]);
halfOfImage.Draw(new CGRect(size.Width / 2, 0, size.Width, size.Height));
}
else
{
// Draw top right quadrant.
images[1].Draw(new CGRect(size.Width / 2, 0, size.Width, size.Height));
// Draw bottom right quadrant.
images[2].Draw(new CGRect(size.Width / 2, size.Height / 2, size.Width / 2, size.Height / 2));
}
if (images.Count >= 4)
{
// Draw top left quadrant.
images[0].Draw(new CGRect(0, 0, size.Width / 2, size.Height / 2));
// Draw bottom left quadrant.
images[3].Draw(new CGRect(0, size.Height / 2, size.Width / 2, size.Height / 2));
}
UIImage newImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(newImage);
}
UIImage CreatePreviewTabBackgroundImage()
{
// The preview tab should be flat on the bottom, and have rounded corners on top.
var size = new SizeF(PreviewTabMinimumWidth, PreviewTabHeight);
UIGraphics.BeginImageContextWithOptions(size, false, UIScreen.MainScreen.Scale);
var rect = new RectangleF(0f, 0f, PreviewTabMinimumWidth, PreviewTabHeight);
var radii = new SizeF(PreviewTabCornerRadius, PreviewTabCornerRadius);
var roundedTopCornersRect = UIBezierPath.FromRoundedRect(rect, UIRectCorner.TopLeft | UIRectCorner.TopRight, radii);
StyleUtilities.ForegroundColor.SetColor();
roundedTopCornersRect.Fill();
UIImage previewTabBackgroundImage = UIGraphics.GetImageFromCurrentImageContext();
var caps = new UIEdgeInsets(0f, PreviewTabCornerRadius, 0f, PreviewTabCornerRadius);
previewTabBackgroundImage = previewTabBackgroundImage.CreateResizableImage(caps);
UIGraphics.EndImageContext();
return(previewTabBackgroundImage);
}
public UIImage MaxResizeImage(UIImage sourceImage, float maxWidth, float maxHeight)
{
Console.WriteLine("Re Size original image");
var sourceSize = sourceImage.Size;
var maxResizeFactor = Math.Min(maxWidth / sourceSize.Width, maxHeight / sourceSize.Height);
if (maxResizeFactor > 1)
{
return(sourceImage);
}
var width = maxResizeFactor * sourceSize.Width;
var height = maxResizeFactor * sourceSize.Height;
UIGraphics.BeginImageContext(new CGSize(width, height));
sourceImage.Draw(new CGRect(0, 0, width, height));
var resultImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(resultImage);
}
protected virtual UIImage GenerateFullProgressImage()
{
UIImage resultImage;
UIGraphics.BeginImageContextWithOptions(Bounds.Size, false, UIScreen.MainScreen.Scale);
using (var context = UIGraphics.GetCurrentContext())
using (var path = BezierPathGenerator.Bagel(CenterPoint, startRadius, endRadius, 0f, FullCircleAngle))
{
context.SaveState();
context.SetFillColor(Color.CGColor);
context.AddPath(path.CGPath);
context.FillPath();
context.RestoreState();
resultImage = UIGraphics.GetImageFromCurrentImageContext();
}
return(resultImage);
}
private void DrawLine(CGPoint point1, CGPoint point2)
{
var size = this.Frame.Size;
UIGraphics.BeginImageContext(size);
this.Control.Image.Draw(new CGRect(0, 0, size.Width, size.Height));
var context = UIGraphics.GetCurrentContext();
context.SetLineCap(CGLineCap.Round);
context.SetLineWidth((nfloat)_formsView.LineWidth);
context.SetStrokeColor(_formsView.PaintColor.ToCGColor());
context.BeginPath();
context.MoveTo(point1.X - 0.5f, point1.Y - 0.5f);
context.AddLineToPoint(point2.X - 0.5f, point2.Y - 0.5f);
context.StrokePath();
this.Control.Image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
}
UIImage CreateGradientBackground(Color startColor, Color endColor, CustomNavigationPage.GradientDirection direction)
{
var gradientLayer = new CAGradientLayer();
gradientLayer.Bounds = NavigationController.NavigationBar.Bounds;
gradientLayer.Colors = new CGColor[] { startColor.ToCGColor(), endColor.ToCGColor() };
switch (direction)
{
case CustomNavigationPage.GradientDirection.LeftToRight:
gradientLayer.StartPoint = new CGPoint(0.0, 0.5);
gradientLayer.EndPoint = new CGPoint(1.0, 0.5);
break;
case CustomNavigationPage.GradientDirection.RightToLeft:
gradientLayer.StartPoint = new CGPoint(1.0, 0.5);
gradientLayer.EndPoint = new CGPoint(0.0, 0.5);
break;
case CustomNavigationPage.GradientDirection.BottomToTop:
gradientLayer.StartPoint = new CGPoint(1.0, 1.0);
gradientLayer.EndPoint = new CGPoint(0.0, 0.0);
break;
default:
gradientLayer.StartPoint = new CGPoint(1.0, 0.0);
gradientLayer.EndPoint = new CGPoint(0.0, 1.0);
break;
}
UIGraphics.BeginImageContext(gradientLayer.Bounds.Size);
gradientLayer.RenderInContext(UIGraphics.GetCurrentContext());
UIImage image = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
return(image);
}
public static UIImage ScaleImage(this UIImage owner, CGSize size, float screenScale = 0f)
{
if (null == owner)
{
throw new NullReferenceException("Image object is null!");
} //end if
UIImage toReturn = null;
UIGraphics.BeginImageContextWithOptions(size, false, screenScale);
using (var context = UIGraphics.GetCurrentContext())
{
context.TranslateCTM(0f, size.Height);
context.ScaleCTM(1f, -1f);
context.DrawImage(new CGRect(0f, 0f, size.Width, size.Height), owner.CGImage);
toReturn = UIGraphics.GetImageFromCurrentImageContext();
} //end using context
UIGraphics.EndImageContext();
return(toReturn);
} //end static UIImage ScaleImage
public static UIImage OverlayWithColor(this UIImage image, UIColor color, float alpha = 1)
{
var size = image.Size;
UIGraphics.BeginImageContextWithOptions(size, false, 2);
try
{
using (var context = UIGraphics.GetCurrentContext())
{
image.Draw(CGPoint.Empty, CGBlendMode.Normal, 1);
context.SetFillColor(color.CGColor);
context.SetBlendMode(CGBlendMode.Overlay);
context.SetAlpha(alpha);
context.FillRect(new CGRect(0, 0, size.Width, size.Height));
return(UIGraphics.GetImageFromCurrentImageContext());
}
}
finally
{
UIGraphics.EndImageContext();
}
}