Question

我一直在尝试在RelativeLayout中设置一个View，但是发生了一些奇怪的事情。当我将LayoutParams设置为MATCH_PARENT时，视图未显示。但是，当我手动设置LayoutParams的大小时，View会正确显示。这是我的代码：

protected void onCreate(Bundle savedInstanceState) {
...
    RelativeLayout layout = new RelativeLayout(this);
    RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
        LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
    layout.setLayoutParams(params);

    rectangle = new Rectangle (this);   
    RelativeLayout.LayoutParams rectParams = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT,
           LayoutParams.MATCH_PARENT);
    rectangle.setLayoutParams(rectParams); 
    //rectangle.setLayoutParams(new LayoutParams(2000, 1280)); If I do this the Rectangle shows correctly

    rectangle.setX(valueX);
    rectangle.setX(valueY);
    layout.addView(rectangle);
}
class Rectangle extends View {
    Paint paint = new Paint();
    Paint paint2 = new Paint();
    RectF rect = new RectF();
    public Rectangle(Context context) {
        super(context);   
    }

    @Override
    public void onDraw(Canvas canvas) {      
        paint.setColor(Color.rgb(255,20,147));
        rect.set(10, 10, 250, 90);
        paint.setStyle(Paint.Style.FILL);
        canvas.drawRoundRect(rect, 3, 3, paint);

        paint2.setColor(Color.WHITE);
        rect.set(10, 10, 250, 90);
        paint2.setStrokeWidth(5);
        paint2.setStyle(Paint.Style.STROKE);
        canvas.drawRoundRect(rect, 5, 5, paint2);
        canvas.drawLine(210, 39, 230,54, paint2);
        canvas.drawLine(210, 63, 230,52, paint2);
        super.onDraw(canvas);           
    }
}

布局对象位于滚动内。我一直试图改变LayoutParameters但没有成功。没有看到任何东西。有什么想法吗？

Answer 1

问题可能是您将容器的布局高度（RelativeLayout）设置为WRAP_CONTENT，将内容的高度（Rectangle）设置为MATCH_PARENT。尝试改变

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);

与

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);

此外，您调用两次setX（我想第二次调用setY）：

rectangle.setY(valueY);

Android RelativeLayout不会显示View

1 个答案: