如何在特定的LinearLayout中添加Canvas？

public class CustomCanvasView extends ViewGroup {
    private Canvas canvas;

    public CustomCanvasView(Context context) {
        super(context);
    }

    public CustomCanvasView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public CustomCanvasView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        // 在这里进行子View的布局
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        // 在这里进行自定义View的尺寸测量
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        this.canvas = canvas;
        // 在这里进行Canvas的绘制
    }

    // 提供一些方法来绘制Canvas
    public void drawSomething() {
        // 在这里进行Canvas的绘制操作
    }
}

    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <com.example.customcanvasview.CustomCanvasView
        android:id="@+id/custom_canvas_view"
        android:layout_width="match_parent"
        android:layout_height="200dp" />

</LinearLayout>

CustomCanvasView customCanvasView = findViewById(R.id.custom_canvas_view);
customCanvasView.drawSomething();