How to draw a triangle, a star, a square or a heart on the canvas?

For everybody that needs a heart shape:

    import android.content.Context;
    import android.graphics.Canvas;
    import android.graphics.Color;
    import android.graphics.Paint;
    import android.graphics.Paint.Style;
    import android.graphics.Path;
    import android.view.View;

    public class Heart extends View {

        private Path path;

        private Paint paint;

        public Heart(Context context) {
            super(context);

            path = new Path();
            paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        }

            @Override
            protected void onDraw(Canvas canvas) {
                super.onDraw(canvas);

                // Fill the canvas with background color
                canvas.drawColor(Color.WHITE);
                paint.setShader(null);

                float width = getContext().getResources().getDimension(R.dimen.heart_width);
                float height = getContext().getResources().getDimension(R.dimen.heart_height);

                // Starting point
                path.moveTo(width / 2, height / 5); 

                // Upper left path
                path.cubicTo(5 * width / 14, 0,
                        0, height / 15,
                        width / 28, 2 * height / 5);

                // Lower left path
                path.cubicTo(width / 14, 2 * height / 3,
                        3 * width / 7, 5 * height / 6,
                        width / 2, height);

                // Lower right path
                path.cubicTo(4 * width / 7, 5 * height / 6,
                        13 * width / 14, 2 * height / 3,
                        27 * width / 28, 2 * height / 5);

                // Upper right path
                path.cubicTo(width, height / 15,
                        9 * width / 14, 0,
                        width / 2, height / 5);

                paint.setColor(Color.RED);
                paint.setStyle(Style.FILL);
                canvas.drawPath(path, paint);

            }
    }

Sorry for all the numbers but these worked best for me :) The result looks like this:

For future direct answer seekers, I have drawn an almost symmetric star using canvas, as shown in the image:

The main tool is using Paths.

Assuming you have setup:

Paint paint = new Paint();
paint.setColor(Color.WHITE);
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);

Path path = new Path();

Then in you onDraw you can use the path like I do below. It will scale properly to any sizes canvas

@Override
protected void onDraw(Canvas canvas) {

    float mid = getWidth() / 2;
    float min = Math.min(getWidth(), getHeight());
    float fat = min / 17;
    float half = min / 2;
    float rad = half - fat;
    mid = mid - half;

    paint.setStrokeWidth(fat);
    paint.setStyle(Paint.Style.STROKE);

    canvas.drawCircle(mid + half, half, rad, paint);

    path.reset();

    paint.setStyle(Paint.Style.FILL);


        // top left
        path.moveTo(mid + half * 0.5f, half * 0.84f);
        // top right
        path.lineTo(mid + half * 1.5f, half * 0.84f);
        // bottom left
        path.lineTo(mid + half * 0.68f, half * 1.45f);
        // top tip
        path.lineTo(mid + half * 1.0f, half * 0.5f);
        // bottom right
        path.lineTo(mid + half * 1.32f, half * 1.45f);
        // top left
        path.lineTo(mid + half * 0.5f, half * 0.84f);

        path.close();
        canvas.drawPath(path, paint);

    super.onDraw(canvas);

}