如何配置ListView以自动更改其高度?

我以这种方式实现了它(代码正在进行中,所以它更像是一个想法源,而不是解决方案):

package com.customcontrols;
public class NoScrollListView extends ListView
{
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
    {
        super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0) );

        // here I assume that height's being calculated for one-child only, seen it in ListView's source which is actually a bad idea
        int childHeight = getMeasuredHeight() - (getListPaddingTop() + getListPaddingBottom() +  getVerticalFadingEdgeLength() * 2);

        int fullHeight = getListPaddingTop() + getListPaddingBottom() + childHeight*(getCount());

        setMeasuredDimension(getMeasuredWidth(), fullHeight);
    }
}

com.customcontrol.NoScrollListView /滚动视图

scrollView非常重要,因为您可以很容易地超出屏幕范围。

由于ListView中的大多数计算方法;Co是包私有的,这对于UI的可公开继承类来说是一个非常奇怪的选择。

这里不是编辑我以前的答案,而是我的实际版本(在案件最终成为问题之后,我不得不修复它)

    @Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
    super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0));

    int childHeight = getMeasuredHeight() - (getListPaddingTop() + getListPaddingBottom() +  getVerticalFadingEdgeLength() * 2);

    // on a first run let's have a space for at least one child so it'll trigger remeasurement
    int fullHeight = getListPaddingTop() + getListPaddingBottom() + childHeight*(getCount());

    int newChildHeight = 0;
    for (int x = 0; x<getChildCount(); x++ ){
        View childAt = getChildAt(x);

        if (childAt != null) {
            int height = childAt.getHeight();
            newChildHeight += height;
        }
    }

    //on a second run with actual items - use proper size
    if (newChildHeight != 0)
        fullHeight = getListPaddingTop() + getListPaddingBottom() + newChildHeight;

    setMeasuredDimension(getMeasuredWidth(), fullHeight);
}

最棘手的部分是onMeasure被调用了两次,首先用于近似布局,然后在添加项之后用于精确布局,两者都必须返回正常的结果。

set ListView Height Based On Children ,这项工作

public static void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter(); 
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
    listView.requestLayout();
}

列表视图xml编码

<ListView
 android:id="@+id/my_listview"
 android:layout_width="match_parent"
 android:layout_height="match_parent" />

列表视图java编码

    ListView lView = (ListView)findViewById(R.id.my_listview);
    lView.setAdapter(adapter);
    setListViewHeightBasedOnChildren(lView);

setListViewHeightBasedOnChildren方法

public static void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null) {
        return;
    }

    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
    listView.requestLayout();
}

您可以尝试在 ListView ViewGroup ),找出他们的高度,求和,然后改变你的想法 列表视图

话虽如此,我完全认为这会很糟糕:

• 你需要考虑屏幕的大小,这样你的列表就不会超出屏幕的界限
• 你需要考虑到方向的变化
• 等。

MergeAdapter 我可以在这里帮忙。