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androidandroid-shape

View background with cut off corner and border


I am trying to make an Android View with a background like this:
enter image description here

I have figured out that the easiest way, properly is to make two shapes on top of each other with different background colors:

enter image description here

The height of the is different for each element, so I need to make the shape in code.
At first I have started in xml to quickly see the results. I have used the principles from this post to get started, but I don't really get close to anything usefull:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <rotate
            android:fromDegrees="45"
            android:toDegrees="45"
            android:pivotX="-60%"
            android:pivotY="50%" >
            <shape
                android:shape="rectangle">
                <solid
                    android:color="#FF00FF" />
            </shape>
        </rotate>
    </item>
</layer-list>


How should I do this?
Any clues of direction would be appriciated



I have done it in iOS like this but the shapes doesn't work the same way in Android:

self.view.backgroundColor = [self getEventColor];
CALayer *backgroundLayer = self.view.layer;

CAShapeLayer *mask = CAShapeLayer.new;
mask.frame = backgroundLayer.bounds;
mask.fillColor = [[UIColor blackColor] CGColor];

CGFloat width = backgroundLayer.frame.size.width;
CGFloat height = backgroundLayer.frame.size.height;

CGMutablePathRef path = CGPathCreateMutable();

int cornerCutSize = 20;
if (cornerCutSize > height)
    cornerCutSize = (int) height - 5;
CGPathMoveToPoint(path, NULL, 0, 0);
CGPathAddLineToPoint(path, nil, width, 0);
CGPathAddLineToPoint(path, nil, width, height - cornerCutSize);
CGPathAddLineToPoint(path, nil, width - cornerCutSize, height);
CGPathAddLineToPoint(path, nil, width, height);
CGPathAddLineToPoint(path, nil, 0, height);
CGPathAddLineToPoint(path, nil, 0, 0);
CGPathCloseSubpath(path);

mask.path = path;
CGPathRelease(path);

backgroundLayer.mask = mask;

UIColor *shadowColor = [[UIColor blackColor] colorWithAlphaComponent:0.12];
self.topView.backgroundColor = shadowColor;

//add border
CAShapeLayer *border = [CAShapeLayer new];
border.frame = backgroundLayer.bounds;
border.path = path;
border.lineWidth = ProgramItemBorderSize;
border.strokeColor = shadowColor.CGColor;
border.fillColor = nil;
[backgroundLayer addSublayer:border];

Solution

  • If all you have to deal with is varying height, make it a 9 patch drawable. Check out the developer guide : http://developer.android.com/guide/topics/graphics/2d-graphics.html#nine-patch http://developer.android.com/tools/help/draw9patch.html

    If you want something closer to your iOS code, you could use a Path and draw to a canvas. For example, you could create a custom drawable to do this:

    import android.graphics.Canvas;
    import android.graphics.Color;
    import android.graphics.ColorFilter;
    import android.graphics.Paint;
    import android.graphics.Path;
    import android.graphics.drawable.Drawable;
    
    public class PathDrawable extends Drawable {
    
        Path mPath = new Path();
        Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    
        public PathDrawable(){
            mPaint.setColor(Color.GRAY);
            mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
            mPaint.setStrokeWidth(5);
        }
    
        @Override
        public void draw(Canvas canvas) {
            mPath.moveTo(10,10);
            mPath.lineTo(10, canvas.getHeight()-10);
            mPath.lineTo(canvas.getWidth()-50, canvas.getHeight()-10);
            mPath.lineTo(canvas.getWidth()-10, canvas.getHeight()-50);
            mPath.lineTo(canvas.getWidth()-10, 10);
            mPath.close();
            canvas.drawPath(mPath, mPaint);
    
        }
    
        @Override
        public void setAlpha(int i) {}
    
        @Override
        public void setColorFilter(ColorFilter colorFilter) {}
    
        @Override
        public int getOpacity() {
            return 0;
        }
    
    
    }
    

    Here I just draw one of the shapes, but you should get the idea.