我到处寻找这个问题的解决方案,我能找到的唯一答案似乎是“不要把一个ListView放入一个ScrollView”。不过,我还没有看到任何真正的解释。我能找到的唯一原因似乎是谷歌认为你不应该这么做。我知道,所以我做了。

问题是,如何将ListView放到ScrollView中而不缩到最小高度?


当前回答

下面是我的计算列表视图总高度的代码版本。这个对我很有用:

   public static void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null || listAdapter.getCount() < 2) {
        // pre-condition
        return;
    }

    int totalHeight = 0;
    int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(BCTDApp.getDisplaySize().width, View.MeasureSpec.AT_MOST);
    int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    ViewGroup.LayoutParams lp = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);

    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        if (listItem instanceof ViewGroup) listItem.setLayoutParams(lp);
        listItem.measure(widthMeasureSpec, heightMeasureSpec);
        totalHeight += listItem.getMeasuredHeight();
    }

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

其他回答

虽然建议的setListViewHeightBasedOnChildren()方法在大多数情况下都可以工作,但在某些情况下,特别是对于许多项,我注意到最后一个元素不显示。所以我决定模仿一个简单版本的ListView行为,以便重用任何适配器代码,这里是ListView的替代方案:

import android.content.Context;
import android.database.DataSetObserver;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.ListAdapter;

public class StretchedListView extends LinearLayout {

private final DataSetObserver dataSetObserver;
private ListAdapter adapter;
private OnItemClickListener onItemClickListener;

public StretchedListView(Context context, AttributeSet attrs) {
    super(context, attrs);
    setOrientation(LinearLayout.VERTICAL);
    this.dataSetObserver = new DataSetObserver() {
        @Override
        public void onChanged() {
            syncDataFromAdapter();
            super.onChanged();
        }

        @Override
        public void onInvalidated() {
            syncDataFromAdapter();
            super.onInvalidated();
        }
    };
}

public void setAdapter(ListAdapter adapter) {
    ensureDataSetObserverIsUnregistered();

    this.adapter = adapter;
    if (this.adapter != null) {
        this.adapter.registerDataSetObserver(dataSetObserver);
    }
    syncDataFromAdapter();
}

protected void ensureDataSetObserverIsUnregistered() {
    if (this.adapter != null) {
        this.adapter.unregisterDataSetObserver(dataSetObserver);
    }
}

public Object getItemAtPosition(int position) {
    return adapter != null ? adapter.getItem(position) : null;
}

public void setSelection(int i) {
    getChildAt(i).setSelected(true);
}

public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
    this.onItemClickListener = onItemClickListener;
}

public ListAdapter getAdapter() {
    return adapter;
}

public int getCount() {
    return adapter != null ? adapter.getCount() : 0;
}

private void syncDataFromAdapter() {
    removeAllViews();
    if (adapter != null) {
        int count = adapter.getCount();
        for (int i = 0; i < count; i++) {
            View view = adapter.getView(i, null, this);
            boolean enabled = adapter.isEnabled(i);
            if (enabled) {
                final int position = i;
                final long id = adapter.getItemId(position);
                view.setOnClickListener(new View.OnClickListener() {

                    @Override
                    public void onClick(View v) {
                        if (onItemClickListener != null) {
                            onItemClickListener.onItemClick(null, v, position, id);
                        }
                    }
                });
            }
            addView(view);

        }
    }
}
}

这肯定会工作............ 你必须替换你的<ScrollView ></ScrollView>在布局XML文件与这个自定义ScrollView像<com.tmd.utils。VerticalScrollview > </com.tmd.utils。VerticalScrollview >

package com.tmd.utils;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.ScrollView;

public class VerticalScrollview extends ScrollView{

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

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

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

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        final int action = ev.getAction();
        switch (action)
        {
            case MotionEvent.ACTION_DOWN:
                    Log.i("VerticalScrollview", "onInterceptTouchEvent: DOWN super false" );
                    super.onTouchEvent(ev);
                    break;

            case MotionEvent.ACTION_MOVE:
                    return false; // redirect MotionEvents to ourself

            case MotionEvent.ACTION_CANCEL:
                    Log.i("VerticalScrollview", "onInterceptTouchEvent: CANCEL super false" );
                    super.onTouchEvent(ev);
                    break;

            case MotionEvent.ACTION_UP:
                    Log.i("VerticalScrollview", "onInterceptTouchEvent: UP super false" );
                    return false;

            default: Log.i("VerticalScrollview", "onInterceptTouchEvent: " + action ); break;
        }

        return false;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        super.onTouchEvent(ev);
        Log.i("VerticalScrollview", "onTouchEvent. action: " + ev.getAction() );
         return true;
    }
}

你不应该把ListView放到ScrollView中因为ListView已经是一个ScrollView了。这就像把一个ScrollView放到一个ScrollView中。

你想要完成什么?

这是DougW、Good Guy Greg和Paul的答案组合。我发现当尝试使用自定义列表视图适配器和非标准列表项时,这都是需要的,否则列表视图会导致应用程序崩溃(也会导致Nex的答案崩溃):

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

        int totalHeight = listView.getPaddingTop() + listView.getPaddingBottom();
        for (int i = 0; i < listAdapter.getCount(); i++) {
            View listItem = listAdapter.getView(i, null, listView);
            if (listItem instanceof ViewGroup)
                listItem.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
            listItem.measure(0, 0);
            totalHeight += listItem.getMeasuredHeight();
        }

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

我把@DougW的实用程序转换成c#(在Xamarin中使用)。下面的代码对于列表中固定高度的项目很有效,如果只有一些项目比标准项目稍大一点,那么大多数项目都将很好,或者至少是一个良好的开端。

// You will need to put this Utility class into a code file including various
// libraries, I found that I needed at least System, Linq, Android.Views and 
// Android.Widget.
using System;
using System.Linq;
using Android.Views;
using Android.Widget;

namespace UtilityNamespace  // whatever you like, obviously!
{
    public class Utility
    {
        public static void setListViewHeightBasedOnChildren (ListView listView)
        {
            if (listView.Adapter == null) {
                // pre-condition
                return;
            }

            int totalHeight = listView.PaddingTop + listView.PaddingBottom;
            for (int i = 0; i < listView.Count; i++) {
                View listItem = listView.Adapter.GetView (i, null, listView);
                if (listItem.GetType () == typeof(ViewGroup)) {
                    listItem.LayoutParameters = new LinearLayout.LayoutParams (ViewGroup.LayoutParams.MatchParent, ViewGroup.LayoutParams.WrapContent);
                }
                listItem.Measure (0, 0);
                totalHeight += listItem.MeasuredHeight;
            }

            listView.LayoutParameters.Height = totalHeight + (listView.DividerHeight * (listView.Count - 1));
        }
    }
}

谢谢@DougW,当我不得不使用其他人的代码时,这让我摆脱了困境。: -)