ListView setChoiceMode not showing up

2020-07-27 03:35发布

问题:

I have a ListView that is put together using a special adapter so that I can show every other listview in a different color. How do I write my code so that I am able to see a checklist without having to extend ListActivity (my activity only extends Activity) Here is my code.

 public class TrackingMe extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);

    setContentView(R.layout.trackingme_layout);

    getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE,
            R.layout.custom_title_3);

    SharedPreferences prefs = getSharedPreferences("Settings", 0);
    final String id = prefs.getString("ID", "");

    final TextView myTitleText = (TextView) findViewById(R.id.tvTitle3);
    if (myTitleText != null)
        myTitleText.setText(getResources().getString(R.string.Trackingme));

    ImageButton addFriends = (ImageButton) findViewById(R.id.btnAddFriends);
    addFriends.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Intent addFriends = new Intent("com.cellphone.INVITEFOLLOWER");
            startActivity(addFriends);
        }
    });

    final ListView lv2 = (ListView) findViewById(R.id.trackingmelistview);
    lv2.setChoiceMode(2);
    lv2.setTextFilterEnabled(true);
    refreshList(id,lv2);

    ImageButton refresh = (ImageButton) findViewById(R.id.btnRefresh2);
    refresh.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub

            refreshList(id, lv2);

        }
    });
}

static final ArrayList<HashMap<String, String>> list2 = new ArrayList<HashMap<String, String>>();

private void refreshList(String id, ListView lv) {
    // removes the list and rebuilds it will choose different response
    // string to get the refreshed times.
    DefaultHttpClient httpclient = new DefaultHttpClient();
    HttpPost httpost = new HttpPost(
            "http://iphone-radar.com/people_i_follow");

    JSONObject holder = new JSONObject();
    try {
        holder.put("userid", id);
        // pacific time zone for now

        StringEntity se = new StringEntity(holder.toString());
        httpost.setEntity(se);
        httpost.setHeader("Accept", "application/json");
        httpost.setHeader("Content-type", "application/json");

        ResponseHandler responseHandler = new BasicResponseHandler();
        final String response = httpclient
                .execute(httpost, responseHandler);
        list2.removeAll(list2);


        SpecialAdapter adapter = new SpecialAdapter(this, list2,
                R.layout.trackingme_row_layout, new String[] { "name" }, new int[] { R.id.tvTrackingMeNames});


        org.json.JSONObject obj = new org.json.JSONObject(response);
        JSONArray tracking_users = obj.getJSONArray("d");

        for (int i = 0; i < tracking_users.length(); i++) {
            // for loop to get all data
            HashMap<String, String> temp = new HashMap<String, String>();
            JSONObject user = tracking_users.getJSONObject(i);
            temp.put("name", user.getString("full_name"));
            list2.add(temp);
            // upload location time

        }

        lv.setAdapter(adapter);
    } catch (JSONException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

}
    //here is the special adapter so that everyother line is a different color
    public class SpecialAdapter extends SimpleAdapter {
private int[] colors = new int[] { Color.GRAY, Color.WHITE };

public SpecialAdapter(Context context,
        ArrayList<HashMap<String, String>> list, int resource,
        String[] from, int[] to) {
    super(context, list, resource, from, to);

}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View view = super.getView(position, convertView, parent);
    int colorPos = position % colors.length;
    view.setBackgroundColor(colors[colorPos]);
    return view;
}
  }

So far it shows up as a line of text based on what I get from my source. However, when I click on individual lines, they don't highlight and even though I wrote lv.setChoiceMode(2), there was no checkbox next to the listview. Thanks

EDIT here is my trackingme_row_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">

    <TextView 
        android:id="@+id/tvTrackingMeNames"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_marginLeft="31dp"              
        android:text="TextView"  
        android:textAppearance="?android:attr/textAppearanceMedium"  
        android:textColor="#000000"/>

</RelativeLayout>

and trackingme_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">

    <ListView   
        android:id="@+id/trackingmelistview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:paddingTop="10dp"/>

    <ImageButton 
        android:id="@+id/btnRefresh2" 
        android:text="Refresh" 
        android:src="@android:drawable/stat_notify_sync" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:layout_alignParentBottom="true" 
        android:layout_alignParentLeft="true"/>

</RelativeLayout>

回答1:

Calling setChoiceMode is not enough to display checkboxes beside your list rows. If you are using a basic layout for the rows, try android.R.layout.simple_list_item_multiple_choice. Else, you will have to add a checkbox to your row layout & manage its on/off state yourself in the adapter's getView method.

HTH,

Akshay

P.S: call setChoiceMode(ListView.CHOICE_MODE_MULTIPLE) instead of setChoiceMode(2) .



回答2:

The short answer is that the listView doesn't work good with Layouts.

The easy solution for your problem is remove the outter layout and use a checkbox or an CheckedTextView instead.

Here is the longer answer (Martin answer is the best). What is the difference between the states selected, checked and activated in Android?