Android Shape 形状

Shape继承体系：

Shape (android.graphics.drawable.shapes)
----PathShape (android.graphics.drawable.shapes)
----RectShape (android.graphics.drawable.shapes)
--------ArcShape (android.graphics.drawable.shapes)
--------OvalShape (android.graphics.drawable.shapes)
--------RoundRectShape (android.graphics.drawable.shapes)

RectShape

RectShape rectShape = new RectShape();ShapeDrawable drawable = new ShapeDrawable(rectShape);drawable.getPaint().setColor(Color.RED);drawable.getPaint().setStyle(Paint.Style.FILL); //填充view.setBackgroundDrawable(drawable);

矩形

RoundRectShape

float[] outerRadii = {20, 20, 40, 40, 60, 60, 80, 80};//外矩形 左上、右上、右下、左下 圆角半径//float[] outerRadii = {20, 20, 20, 20, 20, 20, 20, 20};//外矩形 左上、右上、右下、左下 圆角半径RectF inset = new RectF(100, 100, 200, 200);//内矩形距外矩形，左上角x,y距离， 右下角x,y距离float[] innerRadii = {20, 20, 20, 20, 20, 20, 20, 20};//内矩形 圆角半径//RoundRectShape roundRectShape = new RoundRectShape(outerRadii, inset, innerRadii);RoundRectShape roundRectShape = new RoundRectShape(outerRadii, null, innerRadii); //无内矩形ShapeDrawable drawable = new ShapeDrawable(roundRectShape);drawable.getPaint().setColor(Color.MAGENTA);drawable.getPaint().setAntiAlias(true);drawable.getPaint().setStyle(Paint.Style.STROKE);//描边view.setBackground(drawable);

无内矩形的圆角矩形带内矩形的圆角矩形

OvalShape

OvalShape ovalShape = new OvalShape();ShapeDrawable drawable = new ShapeDrawable(ovalShape);drawable.getPaint().setColor(Color.RED);drawable.getPaint().setStyle(Paint.Style.FILL_AND_STROKE);view.setBackgroundDrawable(drawable);

椭圆。而当View的宽高相等时，就绘出了圆

ArcShape

ArcShape arcShape = new ArcShape(45, 270); //顺时针  开始角度45， 扫描的角度270   扇形ShapeDrawable drawable = new ShapeDrawable(arcShape);drawable.getPaint().setColor(Color.RED);drawable.getPaint().setStyle(Paint.Style.FILL);// Bitmap bitmap =  ((BitmapDrawable)getResources().getDrawable(R.drawable.aa)).getBitmap();// BitmapShader bitmapShader = new BitmapShader(bitmap, Shader.TileMode.MIRROR, Shader//                .TileMode.REPEAT);// Matrix matrix = new Matrix();// matrix.preScale(600.00f / bitmap.getWidth(), 600.00f / bitmap.getHeight());//view:w=600,h=600// bitmapShader.setLocalMatrix(matrix);// drawable.getPaint().setShader(bitmapShader);view.setBackgroundDrawable(drawable);

扇形图

结合BitmapShader

PathShape

Path path = new Path();path.moveTo(50, 0);path.lineTo(0, 50);path.lineTo(50, 100);path.lineTo(100, 50);path.lineTo(50, 0);PathShape pathShape = new PathShape(path, 200, 100);ShapeDrawable drawable = new ShapeDrawable(pathShape);drawable.getPaint().setColor(Color.RED);drawable.getPaint().setStyle(Paint.Style.FILL);imageView.setBackgroundDrawable(drawable);

以Path路径对象，来设定图形。

PathShape的构造函数：PathShape(path, stdWidth, stdHeight);

stdWidth：标准宽度

stdHeight：标准高度

在构造PathShape对象时，设置了宽高的标准。内部函数

protected void onResize(float width, float height) {    mScaleX = width / mStdWidth;    mScaleY = height / mStdHeight;}public void draw(Canvas canvas, Paint paint) {    canvas.save();    canvas.scale(mScaleX, mScaleY);    canvas.drawPath(mPath, paint);    canvas.restore();}

Shape基类中有函数 resize()，其中调用了onResize()；ShapeDrawable中会调用resize()。

有了设定的标准宽高，再算出实际宽高与标准宽高的比率，最后在绘制时，画布canvas缩放。

造成的效果： path中的(x,y)坐标值乘以比率值，即是最终呈现出的坐标值(实际内部是缩放的canvas)

比如，这里view的 w=400， h=400

如果标准宽高都等于400，那么canvas最终不缩放，即1:1。

PathShape pathShape = new PathShape(path, 400, 400);

Android Shape 形状_第5张图片 stdx=400, stdy=400

PathShape pathShape = new PathShape(path, 100, 100);

stdx=100, stdy=100

PathShape pathShape = new PathShape(path, 200, 100);

Android Shape 形状_第6张图片 stdx=200, stdy=100