Question

我有以下自定义相对布局：

public class CircleView extends RelativeLayout implements OnDragListener {
    private DropCallback onDrop = null;
    private ImageButton imageButton = null;
    private int radius = -1;
    private double step = -1;
    private double angle = -1;
    private static final int CENTER_ID = 111;

    public CircleView(Context context, DropCallback onDrop, int radius, List<View> views) {
        super(context);

        this.onDrop = onDrop;
        this.radius = radius;
        this.step = (2 * Math.PI) / views.size();

        this.initView(context, views);
    }

    private void initView(Context context, List<View> views) {
        RelativeLayout.LayoutParams layoutParamsView = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.MATCH_PARENT);

        this.setLayoutParams(layoutParamsView);

        RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
        layoutParams.addRule(RelativeLayout.CENTER_HORIZONTAL);
        layoutParams.addRule(RelativeLayout.CENTER_VERTICAL);

        this.imageButton = new ImageButton(context);
        this.imageButton.setId(CENTER_ID);
        this.imageButton.setLayoutParams(layoutParams);
        this.imageButton.setImageResource(R.drawable.ic_power_on);
        this.imageButton.getBackground().setAlpha(0);
        this.imageButton.setOnDragListener(this);

        this.addView(this.imageButton);

        for(View view : views) {
            this.addView(this.placeView(view));
        }
    }

    private View placeView(View view) {
        view.measure(0, 0);
        this.imageButton.measure(0, 0);

        int x = (int)((view.getMeasuredWidth() / 2) + this.radius * Math.cos(this.angle));
        int y = (int)((view.getMeasuredHeight() / 2) + this.radius * Math.sin(this.angle));

        this.angle += this.step;

        int deltaX = view.getMeasuredWidth();
        int deltaY = view.getMeasuredHeight();
        int deltaImageX = this.imageButton.getMeasuredWidth() / 2;
        int deltaImageY = this.imageButton.getMeasuredHeight() / 2;
        int xToDraw = ((x - deltaX) - deltaImageX);
        int yToDraw = ((y - deltaY) - deltaImageY);

        RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
        layoutParams.addRule(RelativeLayout.ABOVE, CENTER_ID);
        layoutParams.addRule(RelativeLayout.RIGHT_OF, CENTER_ID);
        layoutParams.setMargins(xToDraw, 0, 0, yToDraw);

        view.setLayoutParams(layoutParams);

        return view;
    }

    @Override
    public boolean onDrag(View view, DragEvent event) {
        return this.onDrop.onDrop(view, event);
    }
}

我没有这个的xml布局文件，它一直工作到现在。今天我使用这个自定义布局将活动更改为Fragment，我现在需要设置布局。不幸的是，以下内容是不可能的：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    ...

    return inflater.inflate(new CircleView(this, this, 240, this.views), container, false);
}

那么我如何夸大我的自定义相对布局？

Answer 1

您应该创建xml布局，例如circle_view.xml：

<your_package.CircleView android:id="@+id/gcircle_view"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"/>

然后：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    ...

    return inflater.inflate(R.layout.circle_view, container, false);
}

不过，你应该实现构造函数：

    public CircleView(Context context){
        super(context);

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

    }
    public CircleView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

    }

Answer 2

您可以像这样创建充气机：

 LayoutInflater inflater = LayoutInflater.from(context);

然后使用充气机来充气。

Answer 3

只需创建Circle视图的实例并将其添加到容器中：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    ...
    CircleView circleView = new CircleView(this, this, 240, this.views);
    ...
    return circleView;
}

如何以编程方式膨胀自定义RelativeLayout？

3 个答案: