Question

所以我有一个片段，一旦进度条加载完毕，就会出现一个项目的列表视图，但是当LogCat显示我确实收集了这些项目时，屏幕上没有任何内容。为什么是这样？这是我的代码和xml：

爪哇：

private class showView extends AsyncTask<Object,Void,Boolean>{
    Ride[] rides;
    ArrayList<String>aList = new ArrayList<String>();
    List<Ride> ri = new ArrayList<Ride>();
    String[] rideInfo;
    String sessionToken;
    String deviceId;
    String startZip;
    long start;

    protected void onPreExecute(){
        deviceId = device.getDeviceId();
        sessionToken = SessionManager.getSessionToken(getActivity());
        if(sessionToken == null){
            MainActivity.startSignIn(ctx);
        }

    }

    protected Boolean doInBackground(Object... stuff){





        Log.d("addressList", addressList.toString());

        startZip = addressList.get(0).getPostalCode();

        start = (long)c.get(Calendar.DATE);

        reRi = RestQuery.rideSearch(sessionToken, deviceId, startZip, 20, null, 0, start, start);
        if(!(reRi == null)){
        ri = reRi.getRides();
        if(!(ri == null)){
        rides = ri.toArray(new Ride[ri.size()]);
        if(!(rides == null)){

        for(int x = 0; x < rides.length; x++){
            String name = rides[x].getName();
            String type = rides[x].getType();
            String date = rides[x].getStartDate();
            String startL = rides[x].getStartLocation();
            String endL = rides[x].getEndLocation();

            String rideI = type + "/n" + name + "/n" + date + "/n" + startL + "-" + endL;
            Log.d("ride info",rideI);
            System.out.println(rideI);

            aList.add(rideI);
        }

        rideInfo = aList.toArray(new String[aList.size()]);
        }
        else{
            MainActivity.startSignIn(ctx);
        }
        }
        else{
            MainActivity.startSignIn(ctx);
        }
        }

        else{
            MainActivity.startSignIn(ctx);
        }

        return true;
    }

    public void onPostExecute(Boolean results){
        results = false;
        if(reRi.getResult().getType().equalsIgnoreCase("Ok") || reRi.getResult().getMessage().getCode().equalsIgnoreCase("I00001")){
            results = true;
        }
        if(results){
        Adapter adapter = new Adapter(ctx,rideInfo);
        adapter.notifyDataSetChanged();
        listview.setAdapter(adapter);
        switcher.showNext();
        }

        else if(!results){
            if(reRi.getResult().getMessage().getCode().equalsIgnoreCase("E00012") || reRi.getResult().getMessage().getCode().equalsIgnoreCase("E00011")){
                MainActivity.startSignIn(ctx);
            }
            else{
                Toast.makeText(ctx, "Couldn't access rides", Toast.LENGTH_SHORT).show();
            }
        }
        }
    }





private class Adapter extends ArrayAdapter<String>{
    private final Context context;
      private final String[] values;


      public Adapter(Context context, String[] values) {
        super(context, R.layout.browse_fragment, values);
        this.context = context;
        this.values = values;



      }

      public View getView(int position, View convertView, ViewGroup parent) {
            LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View rowView = inflater.inflate(R.layout.browse_fragment, parent, false);
            TextView txtView = (TextView)rowView.findViewById(R.id.yo);

            txtView.setText(Html.fromHtml(values[position]));

            return rowView;
    }


}

}的xml：

<ViewSwitcher 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/browse_fragment_switcher"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="center" >

          <TextView
            android:id="@+id/sup"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Finding possible rides"
            android:textSize="25sp"/>

        <ProgressBar
            android:id="@+id/progressBar1"
            style="?android:attr/progressBarStyleLarge"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />



    </LinearLayout>
<LinearLayout
                android:id="@+id/llCollection"
                android:layout_width="match_parent"
                android:layout_height="match_parent" 
                android:orientation = "vertical">
    <ListView
        android:id="@+id/show_listview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </ListView>

     <TextView
            android:id="@+id/yo"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="No rides could be found at this time"
            android:textSize="25sp"/>

    </LinearLayout>

</ViewSwitcher>

Answer 1

我相信你需要打电话：

adapter.notiftyDataSetChanged();

更新aList内容后。

http://developer.android.com/reference/android/widget/BaseAdapter.html#notifyDataSetChanged()

试试看，让我知道它是否有帮助。

如果你想发布你的其余代码（如果，你在哪里启动异步任务），我可以提供更多的评论。

ListView文本未显示视图切换器

1 个答案: