切掉布局的边角

Question

我在 android 中有一个布局需要某种形状，即：

角被切掉的地方。有没有一种方法可以在不将布局背景设置为图像的情况下以编程方式执行此操作？我希望使应用程序的大小尽可能小，因此必须尽量减少应用程序中的可绘制对象数量。

Answer 1

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.drawable.shapes.Shape;

public class WeirdShape extends Shape {
    private static final int    COLOUR       = Color.BLACK;
    private static final float  STROKE_WIDTH = 1.0f;
    private static final float  CORNER = 35.0f;

    private final Paint border = new Paint();
    private final Path  path;  

    public WeirdShape() {
       path   = new Path();

        border.setColor      (COLOUR);
        border.setStyle      (Paint.Style.FILL);
        border.setStrokeWidth(STROKE_WIDTH);
        border.setAntiAlias  (true);
        border.setDither     (true);
        border.setStrokeJoin (Paint.Join.ROUND);  
        border.setStrokeCap  (Paint.Cap.ROUND);  
    }

    @Override
    protected void onResize(float width, float height) {
        super.onResize(width, height);

        float dx = STROKE_WIDTH/2.0f;
        float dy = STROKE_WIDTH/2.0f;
        float x  = dx;
        float y  = dy;
        float w  = width  - dx;
        float h  = height - dy;

        //RectF arc = new RectF(x,h-2*CORNER,x+2*CORNER,h);

        path.reset();
        path.moveTo(x + CORNER,y);
        path.lineTo(w - CORNER,y);
        path.lineTo(w,y + CORNER);
        path.lineTo(w, h);
        path.lineTo(x + CORNER,h);
       // path.arcTo (arc,90.0f,90.0f);
        path.lineTo(dx,h - CORNER);
        path.lineTo(dx,y);//path.lineTo(dx,y + CORNER);
        path.close();
    }


    @Override
    public void draw(Canvas canvas, Paint paint) {
        // TODO Auto-generated method stub
        canvas.drawPath(path,border);
    }
}

然后使用ShapeDrawable中的自定义Shape作为背景Drawable:

view.setBackground(new ShapeDrawable(new WeirdShape()));

看起来像：

Answer 2

您可以使用Material组件库提供的ShapeAppearanceModel：

    <LinearLayout
        android:id="@+id/layout"
        ..>

与：

    val radius = resources.getDimension(R.dimen.cornerSize16)

    val linearLayout = findViewById<LinearLayout>(R.id.layout)
    val shapeAppearanceModel = ShapeAppearanceModel()
        .toBuilder()
        .setTopRightCorner(CornerFamily.CUT, radius)
        .setBottomLeftCorner(CornerFamily.CUT, radius)
        .build()

    val shapeDrawable = MaterialShapeDrawable(shapeAppearanceModel)
    ViewCompat.setBackground(linearLayout, shapeDrawable)

切掉布局的边角

Cutting the corners off a layout

android

android-linearlayout

android-shapedrawable