void ClipChild(Canvas canvas) { var bounds = new Graphics.RectF(0, 0, canvas.Width, canvas.Height); if (_invalidateClip || _lastPathSize != bounds.Size || _currentPath == null) { _invalidateClip = false; var path = Clip.PathForBounds(bounds); _currentPath = path?.AsAndroidPath(); _lastPathSize = bounds.Size; } if (_currentPath != null) { canvas.ClipPath(_currentPath); } }
void ClipChild(Canvas canvas) { var density = Context.GetDisplayDensity(); var newSize = new SizeF(canvas.Width, canvas.Height); var bounds = new Graphics.RectF(Graphics.Point.Zero, newSize / density); if (_invalidateClip || _lastPathSize != newSize || _currentPath == null) { _invalidateClip = false; var path = Clip.PathForBounds(bounds); _currentPath = path?.AsAndroidPath(scaleX: density, scaleY: density); _lastPathSize = newSize; } if (_currentPath != null) { canvas.ClipPath(_currentPath); } }
void DrawShadow(Canvas canvas) { if (_shadowCanvas == null) { _shadowCanvas = new Canvas(); } if (_shadowPaint == null) { _shadowPaint = new Android.Graphics.Paint { AntiAlias = true, Dither = true, FilterBitmap = true } } ; Graphics.Color solidColor = null; // If need to redraw shadow if (_invalidateShadow) { var viewHeight = _viewBounds.Height(); var viewWidth = _viewBounds.Width(); if (GetChildAt(0) is AView child) { if (viewHeight == 0) { viewHeight = child.MeasuredHeight; } if (viewWidth == 0) { viewWidth = child.MeasuredWidth; } } // If bounds is zero if (viewHeight != 0 && viewWidth != 0) { var bitmapHeight = viewHeight + MaximumRadius; var bitmapWidth = viewWidth + MaximumRadius; // Reset bitmap to bounds _shadowBitmap = Bitmap.CreateBitmap( bitmapWidth, bitmapHeight, Bitmap.Config.Argb8888 ); // Reset Canvas _shadowCanvas.SetBitmap(_shadowBitmap); _invalidateShadow = false; // Create the local copy of all content to draw bitmap as a // bottom layer of natural canvas. base.DispatchDraw(_shadowCanvas); // Get the alpha bounds of bitmap Bitmap extractAlpha = _shadowBitmap.ExtractAlpha(); // Clear past content content to draw shadow _shadowCanvas.DrawColor(Android.Graphics.Color.Black, PorterDuff.Mode.Clear); var shadowOpacity = (float)Shadow.Opacity; if (Shadow.Paint is LinearGradientPaint linearGradientPaint) { var linearGradientShaderFactory = PaintExtensions.GetLinearGradientShaderFactory(linearGradientPaint, shadowOpacity); _shadowPaint.SetShader(linearGradientShaderFactory.Resize(bitmapWidth, bitmapHeight)); } if (Shadow.Paint is RadialGradientPaint radialGradientPaint) { var radialGradientShaderFactory = PaintExtensions.GetRadialGradientShaderFactory(radialGradientPaint, shadowOpacity); _shadowPaint.SetShader(radialGradientShaderFactory.Resize(bitmapWidth, bitmapHeight)); } if (Shadow.Paint is SolidPaint solidPaint) { solidColor = solidPaint.ToColor(); #pragma warning disable CA1416 // https://github.com/xamarin/xamarin-android/issues/6962 _shadowPaint.Color = solidColor.WithAlpha(shadowOpacity).ToPlatform(); #pragma warning restore CA1416 } // Apply the shadow radius var radius = Shadow.Radius; if (radius <= 0) { radius = 0.01f; } if (radius > 100) { radius = MaximumRadius; } _shadowPaint.SetMaskFilter(new BlurMaskFilter(radius, BlurMaskFilter.Blur.Normal)); float shadowOffsetX = (float)Shadow.Offset.X; float shadowOffsetY = (float)Shadow.Offset.Y; if (Clip == null) { _shadowCanvas.DrawBitmap(extractAlpha, shadowOffsetX, shadowOffsetY, _shadowPaint); } else { var bounds = new Graphics.RectF(0, 0, canvas.Width, canvas.Height); var path = Clip.PathForBounds(bounds)?.AsAndroidPath(); path.Offset(shadowOffsetX, shadowOffsetY); _shadowCanvas.DrawPath(path, _shadowPaint); } // Recycle and clear extracted alpha extractAlpha.Recycle(); } else { // Create placeholder bitmap when size is zero and wait until new size coming up _shadowBitmap = Bitmap.CreateBitmap(1, 1, Bitmap.Config.Rgb565 !); } } // Reset alpha to draw child with full alpha if (solidColor != null) #pragma warning disable CA1416 // https://github.com/xamarin/xamarin-android/issues/6962 { _shadowPaint.Color = solidColor.ToPlatform(); } #pragma warning restore CA1416 // Draw shadow bitmap if (_shadowCanvas != null && _shadowBitmap != null && !_shadowBitmap.IsRecycled) { canvas.DrawBitmap(_shadowBitmap, 0.0F, 0.0F, _shadowPaint); } } void ClearShadowResources() { _shadowCanvas?.Dispose(); _shadowPaint?.Dispose(); _shadowBitmap?.Dispose(); _shadowCanvas = null; _shadowPaint = null; _shadowBitmap = null; } }