how to get a list item position by clicking the button inside it?

Question

actually I've read some previous questions about this...

this is the code that I use

auto = (ListView)findViewById(R.id.auto);
String[] projection = new String[] {Browser.BookmarkColumns._ID,Browser.BookmarkColumns.TITLE,Browser.BookmarkColumns.URL};

    String[] displayFields = new String[] {Browser.BookmarkColumns.TITLE, Browser.BookmarkColumns.URL};

    int[] displayViews = new int[] { R.id.text1,R.id.text2 };

    Cursor cur = managedQuery(android.provider.Browser.BOOKMARKS_URI,projection, null, null, null);

    //auto.setAdapter(new SimpleCursorAdapter(this, R.layout.mylist, cur,displayFields, displayViews));

    myAdapter apt = new myAdapter(this, R.layout.mylist, cur,displayFields, displayViews);
    auto.setAdapter(apt);

and class myAdapter

class myAdapter extends SimpleCursorAdapter{

    private Cursor c;
    private Context context;


    public myAdapter(Context context, int layout, Cursor c, String[] from,
            int[] to) {
        super(context, layout, c, from, to);
        // TODO Auto-generated constructor stub
        this.c = c;
        this.context = context;
        AutoList att = new AutoList();
        mListView = att.auto;

    }

    @Override
    public View getView(int pos, View inView, ViewGroup parent) {
           View vix = inView;

           if (vix == null) {
                LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                vix = inflater.inflate(R.layout.mylist, null);
           }
           this.c.moveToPosition(pos);      

           String title = this.c.getString(this.c.getColumnIndex(Browser.BookmarkColumns.TITLE));

           String cont = this.c.getString(this.c.getColumnIndex(Browser.BookmarkColumns.URL));

               TextView text1 = (TextView) vix.findViewById(R.id.text1);
               text1.setText(title);
               TextView text2 = (TextView) vix.findViewById(R.id.text2);
               text2.setText(cont);
               Button butt = (Button) vix.findViewById(R.id.button);
               butt.setOnClickListener(mButt);
               return vix;
    }

    private OnClickListener mButt = new OnClickListener() {
        @Override
        public void onClick(View v) {
        final int position = mListView.getPositionForView((View) v.getParent());
            Log.v("BUTT", "Title clicked, row "+position);
        }
    };

However, when I click the button, I still get a lot of errors like this:

04-10 22:30:55.152: ERROR/AndroidRuntime(695): FATAL EXCEPTION: main
04-10 22:30:55.152: ERROR/AndroidRuntime(695): java.lang.NullPointerException
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at             com.auto2.AutoList$myAdapter$1.onClick(AutoList.java:113)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at   android.view.View.performClick(View.java:2408)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at   android.view.View$PerformClick.run(View.java:8816)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at android.os.Handler.handleCallback(Handler.java:587)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at   android.os.Handler.dispatchMessage(Handler.java:92)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at android.os.Looper.loop(Looper.java:123)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at android.app.ActivityThread.main(ActivityThread.java:4627)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at java.lang.reflect.Method.invokeNative(Native Method)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at java.lang.reflect.Method.invoke(Method.java:521)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at   com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
04-10 22:30:55.152: ERROR/AndroidRuntime(695):     at   dalvik.system.NativeStart.main(Native Method)

That's it! I hope it won't be so difficult to be figured out!

Thanks!

Answer 1

Actually, I used the same approach - just added casting the parent layout and I got the position w/o any exception

public void deleteButtonClick(View v) {
        //TODO Remove favorite - DB + file system
        Toast.makeText(this, "Deleting bookmark", Toast.LENGTH_SHORT).show();
        final int position = getListView().getPositionForView((LinearLayout)v.getParent());
        if (position >= 0) {
            Favorite o = (Favorite) this.getListAdapter().getItem(position);
        }
}

My layout for listview row :

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res/com.bbox.application"
    android:orientation="vertical" android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <com.markupartist.android.widget.ActionBar
        android:id="@+id/actionbar" app:title="@string/ac_title" style="@style/ActionBar" />
    <ListView android:id="@+id/android:list" android:layout_width="fill_parent"
        android:layout_height="wrap_content" android:layout_weight="5"
        android:background="@drawable/categrory_bckgr" />
    <TextView android:id="@+id/android:empty"
        android:layout_width="fill_parent" android:layout_height="wrap_content"
        android:text="@string/main_no_items" />

</LinearLayout>

I hope it'll help.

Answer 2

An easier solution to this probably is when your Activity implements OnClickListener and you set the (casted) Context as OnClickListener to any view you want in the Adapter. For more robust code you can check with instanceof.

public class MyActivity implements OnClickListener {

    // ...

}

public class MyAdapter extends CursorAdapter {

    @Override
    public void bindView(View view, Context context, Cursor cursor) {

        final TextView tv = (View) view.findViewById(R.id.text1);

        setOnClickListener((OnClickListener)context);

        tv.setTag(cursor.getPosition());

    }

}

For convenience you can set the items position in the adapter as Tag of the view. That way you can easily lookup the whole item in the adapter.

Answer 3

We can get the position by implementing onClickListener inside the getView method of adapter.

ADAPTER :

public class DetailsListAdapter extends BaseAdapter {
Context context;
ArrayList<Profile> data;

public DetailsListAdapter(Context context, ArrayList<Profile> data) {
    this.context = context;
    this.data = data;
}

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

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

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

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    ViewHolder viewHolder;
    if (convertView == null) {
        convertView = LayoutInflater.from(context).inflate(R.layout.list_item_logs_details, null);
        viewHolder = new ViewHolder();
        viewHolder.btn = (Button) convertView.findViewById(R.id.log_details_1_a);
        viewHolder.btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                    Log.d("statusPosition","position "+position);
            }
        });
        convertView.setTag(viewHolder);
    } else {
        viewHolder = (ViewHolder) convertView.getTag();
    }

    return convertView;
}

public static class ViewHolder {
    TextView tv2, tv3, tv3a, tv4, tv4a;
    Button btn;
}
}

Answer 4

ListView with Clickable Buttons!!!

Well...., here's the rough method to solve my problem SO FAR....

item.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="fill_parent"
            android:orientation="horizontal"
            android:layout_height="wrap_content">
<TextView android:id="@+id/showTv"
      android:layout_alignParentLeft="true"
      android:gravity="center_vertical"
      android:textSize="24dip"
      android:layout_height="wrap_content"
      android:layout_width="wrap_content" /> 
 <RelativeLayout android:id="@+id/jjjj"
                 android:layout_alignParentRight="true"
                 android:layout_height="wrap_content"
                 android:layout_width="wrap_content">        
      <Button android:id="@+id/gointoBt"
               android:focusable="false"
               android:layout_alignParentRight="true"
               android:text="abc"
               android:layout_height="wrap_content"
               android:layout_width="wrap_content"/> 
      <Button android:id="@+id/chooseBt"
              android:layout_toLeftOf="@id/gointoBt"
              android:layout_marginRight="10dip"
              android:text="text"
              android:focusable="false"
              android:layout_height="wrap_content"
              android:layout_width="wrap_content"/>
  </RelativeLayout> 

MySimpleAdapter：

import ........;

public class MySimpleAdapter extends SimpleAdapter {

private final Context context;
private List<Map<String, Object>> data;
private int resource;
private String[] from;
private int[] to;

public MySimpleAdapter(Context context,List<? extends Map<String, ?>> data, int resource, String[] from,
int[] to) {
   super(context, data, resource, from, to);
   this.context=context;
   this.data=(List<Map<String, Object>>) data;
   this.resource=resource;
   this.from=from;
   this.to=to;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

   LayoutInflater inflater = ((Activity)context).getLayoutInflater();
   View rowView = inflater.inflate(resource, null, true); 
   Map<String, Object> medMap=data.get(position);
   final TextView[] showTv=new TextView[from.length]; 

   for (int i = 0; i < from.length; i++) { 
    showTv[i]=(TextView)rowView.findViewById(to[i]);
    showTv[i].setText(""+medMap.get(from[i]));
   }
Button btn=(Button)rowView.findViewById(R.id.gointoBt);
   Button.OnClickListener mOkOnClickListener = new Button.OnClickListener()
      {
         public void onClick(View v) {
         Log.v("ttttttt", ""+showTv[0].getText());
         Toast.makeText(context,""+showTv[0].getText(), Toast.LENGTH_LONG).show();
         }
     };
 btn.setOnClickListener(mOkOnClickListener); 

     Button btn2=(Button)rowView.findViewById(R.id.chooseBt);
   Button.OnClickListener mOkOnClickListener2 = new Button.OnClickListener()
      {
          public void onClick(View v) {
          Log.v("hhhhhhh", ""+showTv[0].getText());
          Toast.makeText(context,"abc"+showTv[0].getText(), Toast.LENGTH_LONG).show();
          }
      };
   btn2.setOnClickListener(mOkOnClickListener2);     
   return rowView; 
}
}

Activty：

import .......;

public class   ActivityMain extends Activity {

ListView listview;
List<Map<String,Object>> data;
@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setTitle("My work");
   prepareData(); 
   listview =new ListView(this);
   MySimpleAdapter adapter=new MySimpleAdapter(this,data,R.layout.item,new String[]      {"uu"},new int[]{R.id.showTv});

   listview.setAdapter(adapter);                            
     setContentView(listview);

}
private void prepareData(){
   data=new ArrayList<Map<String,Object>>();
   Map<String,Object> item;
   item=new HashMap<String,Object>();
   item.put("uu", "hello");
   data.add(item);
   item=new HashMap<String,Object>();
   item.put("uu", "myyou");
   data.add(item);
   item=new HashMap<String,Object>();
   item.put("uu", "piero");
   data.add(item);
}

}

Thanks for that Man that is so kind to provide this AWESOME yet Mightiest tutorial.... which anyone here couldn't give to the noobs....