如何在另一个自定义视图中添加自定义视图

Question

我有一个自定义视图，想在该自定义视图上再添加一个自定义视图。这是我的自定义视图类：

public class CustomCircle extends View{
float radius;
Paint paint = new Paint();
String message = "";
public CustomCircle(Context context, AttributeSet attrs) {
    super(context, attrs);
}
@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    canvas.drawCircle(getWidth()/2, getHeight()/2,radius, paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
    boolean isClickInCircle = false;
    float x = event.getX();
    float y = event.getY();
    double check = Math.sqrt((x-getWidth()/2)*(x-getWidth()/2) + (y-getHeight()/2)*(y-getHeight()/2));
    if (check<=radius) {
        isClickInCircle= true;
    }
    if (isClickInCircle) {
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            Toast.makeText(getContext(),message, Toast.LENGTH_LONG).show();
            return true;
        case MotionEvent.ACTION_UP:
            Toast.makeText(getContext(), message, Toast.LENGTH_LONG).show();
            return true;
        default:
            break;
        }
    }
    return false;
}

并且正在使用另一个扩展LinearLayout的类：

public class B extends LinearLayout {
private Paint paint;
public B(Context context) {
    super(context);
    paint = new Paint();
    paint.setColor(Color.WHITE);
    paint.setStyle(Style.FILL);
}
public void addCircle() {
    CustomCircle circleBlue = new CustomCircle(getContext(), null);
    circleBlue.paint.setColor(Color.WHITE);
    circleBlue.paint.setAntiAlias(true);
    circleBlue.radius = 160;
    circleBlue.message = "Clicked";
    addView(circleBlue);
    CustomCircle circleRed = new CustomCircle(getContext(), null);
    circleRed.paint.setColor(Color.RED);
    circleRed.paint.setAntiAlias(true);
    circleRed.radius = 80;
    circleRed.message = "Clicked";
    addView(circleRed);
}

我使用以下命令从主活动类调用 B 类：

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    B root = new B(this);
    root.addCircle();
    setContentView(root);
}

输出只显示一个圆圈，而不是另一个圆圈内的圆圈。我的代码有什么问题？

Answer 1

输出只向我显示一个圆圈而不是里面的圆圈 圈。

如果你想重叠孩子，你选错了布局，RelativeLayout或FrameLayout是要走的路。另外，关于您的代码：

public class B extends RelativeLayout {
//...
public void addCircle() {
    // the constructor that uses the AttributeSet should be added if you use the 
    // custom component in the xml layout
    CustomCircle circleBlue = new CustomCircle(getContext());
    // ...
    // add it with LayoutParams
    RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(
                RelativeLayout.LayoutParams.WRAP_CONTENT,
                RelativeLayout.LayoutParams.WRAP_CONTENT);
    rlp.addRule(RelativeLayout.CENTER_IN_PARENT);
    addView(circleBlue, rlp);
    // the same for the other view
}

此外，您的两个圆将具有相同的尺寸，因此它们将完美重叠（并且您将无法看到它们），您需要通过LayoutParams为它们提供不同的尺寸，例如：

RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(200, 200);

对于第一个和：

RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(100, 100);

对于第二个。

Answer 2

布局中是否有 2 个圆圈，但您只能看到一个圆圈因为它与第一个圆圈的颜色相同，并且它们彼此重叠？

更改circleRed.paint.setColor(Color.WHITE);到circleRed.paint.setColor(Color.BLACK);看看它能带来什么