如何在android中使用第二比例的图形视图进行绘图

public class CustomView extends View {
    public CustomView(Context context) {
        super(context);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        
        // 绘制图形
        Paint paint = new Paint();
        paint.setColor(Color.RED);
        paint.setStyle(Paint.Style.FILL);
        
        int width = canvas.getWidth();
        int height = canvas.getHeight();
        
        // 计算第二比例的宽度和高度
        int secondWidth = width / 2;
        int secondHeight = height / 2;
        
        // 绘制矩形
        canvas.drawRect(0, 0, secondWidth, secondHeight, paint);
    }
}

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        // 添加自定义的View到布局中
        CustomView customView = new CustomView(this);
        LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.WRAP_CONTENT,
                LinearLayout.LayoutParams.WRAP_CONTENT
        );
        layoutParams.weight = 0.5f; // 设置第二比例
        customView.setLayoutParams(layoutParams);
        
        LinearLayout layout = findViewById(R.id.layout);
        layout.addView(customView);
    }
}