code: private void customDraw(Canvas canvas) {
          int width = getMeasuredWidth();
          int height = getMeasuredHeight();
          Path path = gotPath(width, height);
          Paint paint = new Paint();
          paint.setAntiAlias(true);
          int[] colors = new int[]{
                  ContextCompat.getColor(getContext(), R.color.hlklib_bezier_curve_background_start),
                  ContextCompat.getColor(getContext(), R.color.hlklib_bezier_curve_background_center),
                  ContextCompat.getColor(getContext(), R.color.hlklib_bezier_curve_background_end)
          };
          Shader shader = new LinearGradient(0, height, width, 0, colors, null, Shader.TileMode.MIRROR);
          paint.setShader(shader);
          paint.setStyle(Paint.Style.FILL);
          canvas.drawPath(path, paint);
      }
docs: 自定义绘制