Android how to use adapter for listView without extending listActivity

Question

I have an application with tabs. In one tab I need to put data (strings) in rows. To do so I chose tableLayout but when I wanted to use a contextmenu on its rows it doesn't work.

I can show the contextmenu onLongClick but the problem is that I can't get the info about the selected row to edit or delete the selected row. Then I read in a discussion that using listView is better than tablelayout if we have many rows. But the examples I saw extend listactivity but I don't want to do this.

So when I try working on a listView without extending listactivity I don't know how to do it what I mean is that I've never used listView before so I try different examples I found on the internet to understand it but it's not working. Here's what I did so far for the listView:

String [] items=getRessources().getStringArray(R.arra.resolution);
 //Resolution is an array of strings
ListView lv=(ListeView) findViewById(R.id.listView);
v.setAdapter(new ArrayAdapter<string>(this, android.R.layout.simple_list_item_1, items);

When I compile it I get a list with elements of my array in it but first, I want to change the color of text which I can't. And secondly I want to add rows dynamically to the list which I don't know how to do either. I think I have to use an adapter to do it but I don't know how. Can someone please guide me through this. I just want to know how to attach my list to an adapter which'll allow me to dynamically add rows, add contextMenu etc.

Answer 1

It appears that noone has answered you contextMenu question. To get a context menu to work with your list , after you call ListView yourList = getListView(); you must call registerForContextMenu(yourList);

And to handle the menu creation you must implement the method

@Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo){ 
super.onCreateContextMenu(context, v,menuInfo);
MenuInflater inflater = getMenuInflater();
menu.setHeaderTitle("YOUR TITLE");
menu.setHeaderIcon(R.drawable.YOUR DRAWABLE);
inflater.inflate(R.menu.YOUR_MENU_RESOURCE, menu);
}

Then you can respond to clicks by implenting the method

@Override public boolean onContextItemSelected(MenuItem item){
switch(item.getItemId()){
case R.id.YOUR_MENU_ITEM: // do stuff if the item is selected
 return true;
case R.id.YOUR_MENU_ITEM: // do stuff if the item is selected
 return true;
case R.id.YOUR_MENU_ITEM: // do stuff if the item is selected
 return true;
 }
 return false; // nothing selected
}

Answer 2

main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/bg8"
    android:id="@+id/RootView"
    >
        <LinearLayout android:id="@+id/myLayout"
            android:layout_width="wrap_content"
            android:layout_height="fill_parent">
       </LinearLayout>

</LinearLayout>

You need to define an xml which will be used to hold data of each row:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" android:weightSum="1">

   <TableRow
       android:id="@+id/tableRow1"
       android:layout_width="793dp"
       android:layout_height="wrap_content"
       android:layout_weight="0.23" >

        <TextView android:id="@+id/col1"
            android:layout_height="fill_parent"
            android:layout_width="wrap_content"
            android:width="50dp"
           android:textSize="18sp"

        />
        <TextView android:id="@+id/col2"
            android:layout_height="fill_parent"
            android:layout_width="wrap_content"
            android:width="150dp"
            android:textSize="18sp"
        />
      <ImageView android:id="@+id/editimage"
            android:background="@drawable/edit"
            android:clickable="true"
            android:onClick="ClickHandlerForEditImage" 
            android:layout_width="35dp" 
         android:layout_height="35dp"/>  

    </TableRow>

</LinearLayout>

In the above xml i have also included the ImageView, it is not really required but this is just to update you that we can include the other controls also.

& at the last you should have a function in your related class:

private void LoadData()
{

    DBAdapter db = new DBAdapter(this);
    db.open();
    Cursor cur = db.GetData();
    private ListView lv = (ListView)findViewById(R.id.myLayout);
    lv.setAdapter(null);
    if(cur.moveToFirst())
    {
            String[] from = new String[] {"_id","column1"};
            int[] to = new int[] {R.id.col1, R.id.col2};
            SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,R.layout.grid_item, cur, from, to);
            lv.setAdapter(adapter);  

     }
       db.close();
         }
}

Answer 3

main Activity class:

import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;

public class SelectedActivity extends Activity {

private SelectedAdapter selectedAdapter;
private ArrayList<String> list;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.selected_example);

    // populate the model - a simple a list
    list = new ArrayList<String>();
    list.add("Apple");
    list.add("Orange");
    list.add("Grape");
    list.add("Grape1");
    list.add("Grape2");
    list.add("Grape3");
    list.add("Grape4");
    list.add("Grape5");
    list.add("Grape6");

    // create our SelectedAdapter
    selectedAdapter = new SelectedAdapter(this,0,list);
    selectedAdapter.setNotifyOnChange(true);

    ListView listview = (ListView) findViewById(R.id.listExample);
    listview.setAdapter(selectedAdapter);

    listview.setOnItemClickListener(new OnItemClickListener() {
        //@Override
        public void onItemClick(AdapterView arg0, View view,
                                       int position, long id) {
            // user clicked a list item, make it "selected"
            selectedAdapter.setSelectedPosition(position);
        }
    });
}

Adapter class:

   import java.util.List;
    import android.content.Context;
    import android.graphics.Color;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.ArrayAdapter;
    import android.widget.Button;
    import android.widget.TextView;

    public class SelectedAdapter extends ArrayAdapter{

        // used to keep selected position in ListView
        private int selectedPos = -1;   // init value for not-selected

        public SelectedAdapter(Context context, int textViewResourceId,
                       List objects) {
             super(context, textViewResourceId, objects);
        }
        public void setSelectedPosition(int pos){
        selectedPos = pos;
             // inform the view of this change
             notifyDataSetChanged();
        }
        public int getSelectedPosition(){
             return selectedPos;
        }
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
                 View v = convertView;
                 // only inflate the view if it's null
                 // if (v == null) {
                        LayoutInflater vi =   (LayoutInflater)this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                        v = vi.inflate(R.layout.selected_row, null);
                 //  }

                 // get text view
                     TextView label = (TextView)v.findViewById(R.id.txtExample);
                     Button btn=(Button)v.findViewById(R.id.btn1);

                     // change the row color based on selected state
                     if(selectedPos == position){
                        label.setBackgroundColor(Color.CYAN);
                        btn.setBackgroundResource(R.drawable.next);
                     }
                     else{
                        label.setBackgroundColor(Color.WHITE);
                     }

                     label.setText(this.getItem(position).toString());       
                     return(v);
        }
}