Android 使用自定义listview适配器时,屏幕上不会显示任何内容

Android 使用自定义listview适配器时,屏幕上不会显示任何内容,android,android-listview,Android,Android Listview,正如标题所述,我在让自定义listview适配器正常工作时遇到了一些问题。该应用程序在列表中不显示任何内容,只显示一个空白的白色屏幕。我用一个已经设置好的简单列表测试了数据,效果很好 History.java public class History { public String score; public String gametype; public int icon; public History() { super(); }

正如标题所述,我在让自定义listview适配器正常工作时遇到了一些问题。该应用程序在列表中不显示任何内容,只显示一个空白的白色屏幕。我用一个已经设置好的简单列表测试了数据,效果很好

History.java

public class History {
    public String score;
    public String gametype;
    public int icon;

    public History() {
        super();
    }

    public History(String score, String gametype, int icon) {
        super();
        this.score = score;
        this.gametype = gametype;
        this.icon = icon;
    }
}
HistoryAdapter.java

public class HistoryAdapter extends ArrayAdapter<History> {

    Context context;
    int layoutResId;
    History data[] = null;

    public HistoryAdapter(Context context, int layoutResId, History[] data) {
        super(context, layoutResId, data);
        this.layoutResId = layoutResId;
        this.context = context;
        this.data = data;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        HistoryHolder holder = null;

        if(convertView == null)
        {
            LayoutInflater inflater = ((Activity)context).getLayoutInflater();
            convertView = inflater.inflate(layoutResId, parent, false);

            holder = new HistoryHolder();
            holder.imageIcon = (ImageView)convertView.findViewById(R.id.icon);
            holder.textTitle = (TextView)convertView.findViewById(R.id.gameType);
            holder.textScore = (TextView)convertView.findViewById(R.id.score);

            convertView.setTag(holder);
        }
        else
        {
            holder = (HistoryHolder)convertView.getTag();
        }

        History history = data[position];
        holder.textScore.setText(history.score);
        holder.textTitle.setText(history.gametype);
        holder.imageIcon.setImageResource(history.icon);


        return convertView;
    }

    static class HistoryHolder
    {
        ImageView imageIcon;
        TextView textTitle;
        TextView textScore;
    }
}
公共类HistoryAdapter扩展了ArrayAdapter{
语境;
int layoutResId;
历史数据[]=null;
公共HistoryAdapter(上下文上下文、int-layoutResId、历史[]数据){
super(上下文、layoutResId、数据);
this.layoutResId=layoutResId;
this.context=上下文;
这个数据=数据;
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组父视图){
HistoryHolder=null;
if(convertView==null)
{
LayoutInflater充气器=((活动)上下文)。getLayoutInflater();
convertView=充气机。充气(layoutResId,父项,false);
holder=新历史holder();
holder.imageIcon=(ImageView)convertView.findViewById(R.id.icon);
holder.textTitle=(TextView)convertView.findViewById(R.id.gameType);
holder.textScore=(TextView)convertView.findViewById(R.id.score);
convertView.setTag(支架);
}
其他的
{
holder=(HistoryHolder)convertView.getTag();
}
历史=数据[位置];
holder.textScore.setText(history.score);
holder.textTitle.setText(history.gametype);
holder.imageIcon.setImageResource(history.icon);
返回视图;
}
静态类历史持有者
{
图像视图图像图标;
文本视图文本标题;
TextView textScore;
}
}
实施

for(int i = 0; i < games.length(); i++) {
                    JSONObject c = games.getJSONObject(i);
                    JSONObject gameStats = games.getJSONObject(i).getJSONObject(TAG_STATS);
                    type[i] = c.getString(TAG_TYPE);
                    champId[i] = c.getString("championId");
                    cs[i] = gameStats.getString("minionsKilled");
                    kills[i] = gameStats.getString("championsKilled");
                    deaths[i] = gameStats.getString("numDeaths");
                    assists[i] = gameStats.getString("assists");
                    win[i] = gameStats.getString("win");

                    if(win[i].equals("true"))
                        win[i] = "Victory";
                    else
                        win[i] = "Defeat";

                    if(type[i].equals("RANKED_SOLO_5x5"))
                        type[i] = "Ranked (Solo)";

                    if(type[i].equals("CAP_5x5"))
                        type[i] = "TeamBuilder";

                    if(type[i].equals("NORMAL"))
                        type[i] = "Unranked";

                    score[i] = kills[i] +"/" + deaths[i] + "/" + assists[i];

                    historyData[i] = new History(score[i], champId[i], R.drawable.ic_launcher); // Placeholder image

                }

                adapter = new HistoryAdapter(MatchHistoryActivity.this,
                        R.layout.list_adapter,
                        historyData);

                list.setAdapter(adapter);
for(int i=0;i
listview.xml

<?xml version="1.0" encoding="utf-8"?>

<ListView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/list"
    android:background="#111111"> 
    </ListView>

list_item.xml

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="?android:attr/listPreferredItemHeight"
    android:background="#111111"
    android:padding="6dip" >

    <ImageView
        android:id="@+id/icon"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_alignParentBottom="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="6dip"
        android:contentDescription="TODO"
        android:src="@drawable/ic_launcher" />

    <TextView
        android:id="@+id/score"
        android:textColor="#C49246"
        android:layout_width="fill_parent"
        android:layout_height="26dip"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="5dp"
        android:layout_toRightOf="@id/icon"
        android:ellipsize="marquee"
        android:singleLine="true"
        android:text="0/0/0 KDA"
        android:textSize="12sp" />

    <TextView
        android:id="@+id/gameType"
        android:textColor="#C49246"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/score"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_alignWithParentIfMissing="true"
        android:layout_marginLeft="5dp"
        android:layout_toRightOf="@id/icon"
        android:gravity="center_vertical"
        android:textSize="16sp" />

</RelativeLayout>

您需要覆盖自定义适配器中的
getCount()
。 它将返回ListView中的条目数

@Override
public int getCount() {
    return myArrayList.size();
}

我认为您应该将
ArrayAdapter
替换为
BaseAdapter
,并实现所有必需的方法,例如
getItemId()、getItem()、getCount()、getView()
它应该很好用!。
下面是我的示例代码,不关心什么是MusicModel

protected class MusicCustomAdapter extends BaseAdapter {

        private Activity context;
        private List<MusicModel> musicModelList;
        private SimpleDateFormat sdf = new SimpleDateFormat("mm:ss");

        public MusicCustomAdapter(Activity context, List<MusicModel> musicModelList) {
            this.context = context;
            this.musicModelList = musicModelList;
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public Object getItem(int position) {
            return this.musicModelList.get(position);
        }

        @Override
        public int getCount() {
            return this.musicModelList.size();
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View view = convertView;
            if (view == null) {
                view = context.getLayoutInflater().inflate(R.layout.song_item, null);
            }

            MusicModel musicModel = (MusicModel) getItem(position);

            TextView tvMusicName = (TextView) view.findViewById(R.id.tv_song_name);
            tvMusicName.setText(musicModel.getName());

            TextView tvArtist = (TextView) view.findViewById(R.id.tv_artist);
            tvArtist.setText(musicModel.getArtist());

            TextView tvDuration = (TextView) view.findViewById(R.id.tv_duration);
            tvDuration.setText(sdf.format(musicModel.getDuration()));

            ImageView imgThumbnail = (ImageView) view.findViewById(R.id.img_thumbnail);
            imgThumbnail.setImageDrawable(musicModel.getThumbnail());

            return view;
        }
    }
受保护类MusicCustomAdapter扩展BaseAdapter{
私人活动语境;
私人名单音乐模特;
私有SimpleDataFormat sdf=新SimpleDataFormat(“mm:ss”);
公共MusicCustomAdapter(活动上下文、列表MusicModelist){
this.context=上下文;
this.musicModelList=musicModelList;
}
@凌驾
公共长getItemId(int位置){
返回0;
}
@凌驾
公共对象getItem(int位置){
返回此.musicModelList.get(位置);
}
@凌驾
public int getCount(){
返回此.musicModelList.size();
}
@凌驾
公共视图getView(int位置、视图转换视图、视图组父视图){
视图=转换视图;
如果(视图==null){
view=context.GetLayoutFlater().inflate(R.layout.song_项,空);
}
MusicModel MusicModel=(MusicModel)获取项目(位置);
TextView tvMusicName=(TextView)view.findViewById(R.id.tv\u song\u name);
tvMusicName.setText(musicModel.getName());
TextView tvArtist=(TextView)view.findViewById(R.id.tv\u-artist);
tvastr.setText(musicModel.getArtist());
TextView tvDuration=(TextView)view.findViewById(R.id.tv_duration);
setText(sdf.format(musicModel.getDuration());
ImageView imgThumbnail=(ImageView)view.findViewById(R.id.img_缩略图);
imgThumbnail.setImageDrawable(musicModel.getThumbnail());
返回视图;
}
}

希望能有所帮助。

透明的
更改你的
列表视图
背景,也用
android:background=“#其他颜色”
@SimplePlan更改你的
列表项相对布局
背景。这样做没有任何结果,留给我同样的东西,一个空白的白色屏幕。您能解释一下为什么我们需要重写getCount()方法,反之亦然。我试图重写getCount()和getItem()方法