protected override void OnDraw(Android.Graphics.Canvas canvas)
{
base.OnDraw(canvas);
if (Borders != null)
{
Android.Graphics.Paint paint = new Android.Graphics.Paint();
paint.Color = Color.Black;
paint.SetStyle(Android.Graphics.Paint.Style.Stroke);
int Height = this.Height;
int Width = this.Width;
if (Borders.Top > 0)
{
paint.StrokeWidth = Borders.Top * 2;
canvas.DrawLine(0, 0, Width, 0, paint);
}
if (Borders.Bottom > 0)
{
paint.StrokeWidth = Borders.Bottom * 2;
canvas.DrawLine(0, Height, Width, Height, paint);
}
if (Borders.Left > 0)
{
paint.StrokeWidth = Borders.Left * 2;
canvas.DrawLine(0, 0, 0, Height, paint);
}
if (Borders.Right > 0)
{
paint.StrokeWidth = Borders.Right * 2;
canvas.DrawLine(Width, 0, Width, Height, paint);
}
paint.Dispose();
}
}
public void Dispose()
{
if (_paint != null)
{
_paint.Dispose();
}
_paint = null;
}
public override void Draw(Canvas canvas)
{
var bounds = Bounds;
using (var paint = new Paint())
{
paint.Color = Color;
canvas.DrawRect(new ARect(0, 0, bounds.Right, TopSize), paint);
canvas.DrawRect(new ARect(0, bounds.Bottom - BottomSize, bounds.Right, bounds.Bottom), paint);
paint.Dispose();
}
}
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;
}
}
private void InitializeImages()
{
if(_pressedImage != null)
{
_pressedImage.Recycle();
_pressedImage.Dispose();
}
if(_unpressedImage != null)
{
_unpressedImage.Recycle();
_unpressedImage.Dispose();
}
_unpressedImage = Bitmap.CreateBitmap(Width, Settings.IsSquared ? Width : Height, Bitmap.Config.Argb8888);
_pressedImage = Bitmap.CreateBitmap(Width, Settings.IsSquared ? Width : Height, Bitmap.Config.Argb8888);
Canvas unpressedCanvas = new Canvas(_unpressedImage);
Canvas pressedCanvas = new Canvas(_pressedImage);
Settings.SetTextSize(ComplexUnitType.Px, Settings.TextSize == 0f ? Height * Settings.TextSizeRatio : Settings.TextSize);
Settings.StrokeBorderWidth = Height * Settings.StrokeBorderWidthRatio;
Settings.StrokeTextWidth = Height * Settings.StrokeTextWidthRatio;
// Background fill paint
Paint fillBackPaint = new Paint();
fillBackPaint.Color = Settings.FillColor;
fillBackPaint.AntiAlias = true;
// Background stroke paint
Paint strokeBackPaint = new Paint();
strokeBackPaint.Color = Settings.StrokeColor;
strokeBackPaint.SetStyle(Paint.Style.Stroke);
strokeBackPaint.StrokeWidth = Settings.StrokeBorderWidth;
strokeBackPaint.AntiAlias = true;
// Text paint
Paint textPaint = new Paint();
textPaint.Color = Settings.IsTextStroked ? Settings.FillColor : Settings.StrokeColor;
textPaint.TextAlign = Paint.Align.Center;
textPaint.TextSize = Settings.TextSize;
textPaint.SetTypeface(Settings.Typeface);
textPaint.AntiAlias = true;
// Text stroke paint
Paint strokePaint = new Paint();
strokePaint.Color = Settings.StrokeColor;
strokePaint.TextAlign = Paint.Align.Center;
strokePaint.TextSize = Settings.TextSize;
strokePaint.SetTypeface(Settings.Typeface);
strokePaint.SetStyle(Paint.Style.Stroke);
strokePaint.StrokeWidth = Settings.StrokeTextWidth;
strokePaint.AntiAlias = true;
// Background bounds
Rect local = new Rect();
this.GetLocalVisibleRect(local);
RectF bounds = new RectF(local);
bounds.Top += Settings.StrokeBorderWidth/2;
bounds.Left += Settings.StrokeBorderWidth/2;
bounds.Right -= Settings.StrokeBorderWidth/2;
bounds.Bottom -= Settings.StrokeBorderWidth/2;
while(bounds.Top > Height)
{
bounds.Top -= Height;
}
while(bounds.Bottom > Height)
{
bounds.Bottom -= Height;
}
while(bounds.Left > Width)
{
bounds.Left -= Width;
}
while(bounds.Right > Width)
{
bounds.Right -= Width;
}
// Text location
Rect r = new Rect();
strokePaint.GetTextBounds(Text, 0, Text.Length, r);
while(r.Width() + Settings.StrokeTextWidth >= bounds.Width())
{
Settings.SetTextSize(ComplexUnitType.Px, Settings.TextSize-1);
textPaint.TextSize = Settings.TextSize;
strokePaint.TextSize = Settings.TextSize;
strokePaint.GetTextBounds(Text, 0, Text.Length, r);
}
float x=0, y=0;
switch (Settings.Gravity)
{
case GravityFlags.Top:
y = PaddingTop + r.Height()/2;
break;
case GravityFlags.Bottom:
y = Height - r.Height()/2 - PaddingBottom;
break;
default:
y = Height / 2f + r.Height() / 2f - r.Bottom;
break;
}
switch (Settings.Gravity)
{
case GravityFlags.Left:
x = PaddingLeft + r.Width()/2;
break;
case GravityFlags.Right:
x = Width - r.Width()/2 - PaddingRight;
break;
default:
x = Width/2;
break;
}
// Draw unpressed
DrawBackground(unpressedCanvas, bounds, fillBackPaint, strokeBackPaint);
if(Settings.IsTextStroked)
unpressedCanvas.DrawText(Text, x, y, strokePaint);
unpressedCanvas.DrawText(Text, x, y, textPaint);
// Change colors
fillBackPaint.Color = Settings.StrokeColor;
strokeBackPaint.Color = Settings.FillColor;
strokePaint.Color = Settings.FillColor;
textPaint.Color = Settings.IsTextStroked ? Settings.StrokeColor : Settings.FillColor;
// Draw pressed
DrawBackground(pressedCanvas, bounds, fillBackPaint, strokeBackPaint);
if(Settings.IsTextStroked)
pressedCanvas.DrawText(Text, x, y, strokePaint);
pressedCanvas.DrawText(Text, x, y, textPaint);
// Set images for states
StateListDrawable states = new StateListDrawable();
states.AddState(new int[] {Android.Resource.Attribute.StatePressed}, new BitmapDrawable(_pressedImage));
states.AddState(new int[] {Android.Resource.Attribute.StateFocused}, new BitmapDrawable(_pressedImage));
states.AddState(new int[] {Android.Resource.Attribute.StateSelected}, new BitmapDrawable(_pressedImage));
states.AddState(new int[] { }, new BitmapDrawable(_unpressedImage));
SetBackgroundDrawable(states);
strokePaint.Dispose();
textPaint.Dispose();
strokeBackPaint.Dispose();
fillBackPaint.Dispose();
unpressedCanvas.Dispose();
pressedCanvas.Dispose();
}
