ListView中的Android圆角

Question

我有一个带圆角的 ListView，使用以下形状作为背景:

<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
<solid android:color="#ffffff"/>
<corners android:bottomRightRadius="13px" android:bottomLeftRadius="13px" android:topLeftRadius="13px" android:topRightRadius="13px"/>
</shape>

问题出在选择器上。 It's rectangle shaped, so when selecting first or last item the corners aren't rounded anymore.我在 http://www.anddev.org/view-layout-resource-problems-f27/rounded-corners-on-listview-t8193-15.html 的最后一篇文章中找到了一个非常好的解决方案。 .问题是我不能让另一个类继承自 ListView。当我唯一拥有的是对现有 ListView 的引用时，如何应用此方法？我必须这样做的原因是布局是从 xml 扩展而来的。

我正在寻找类似的东西:

ListView lv = (ListView)findViewById(...);
lv.onSizeChanged = protected void onSizeChanged(int w, int h, int oldw, int oldh){ ... }

谢谢

Answer 1

看起来除了扩展 ListView 类并在 XML 中使用它之外别无他法。这是示例代码:

public class WListView extends LinearLayout
{
    // =================================================================
    // Variables
    // =================================================================
    private Path clipArea;

    // =================================================================
    // Public methods
    // =================================================================

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

    public WListView(Context context, AttributeSet attr)
    {
        super(context, attr);
    }

    // =================================================================
    // Private methods
    // =================================================================


    @Override
    protected void onSizeChanged(int w, int h, int oldW, int oldH)
    {
        super.onSizeChanged(w, h, oldW, oldH);
        clipArea = new Path();
        RectF rect = new RectF(0, 0, w, h);

        int cornerRadius = 13; // we should convert px to dp here
        clipArea.addRoundRect(rect, cornerRadius, cornerRadius, Path.Direction.CW);
    }

    @Override
    protected void dispatchDraw(Canvas canvas)
    {
        canvas.save();
        canvas.clipPath(clipArea);
        super.dispatchDraw(canvas);
        canvas.restore();
    }
}