scrolling not coming inside grid view

Question

I am developing an app in android.I have one grid view inside my layout. The text to be inserted in grid view i am obtaining from a web service.. This i am putting to an array.. Array size is greater than 18. But when i am using adapter to set to the gridview, it just appears as a bar on the screen.When data is large, scrolling will be enabled ryt?.. but its not coming.

This is my xml layout

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

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >

<ImageButton
    android:id="@+id/cancelbutton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_alignParentRight="true"
    android:background="@android:color/transparent"
    android:onClick="onButtonClick"
    android:src="@drawable/cancel"/>

<Button 
    android:id="@+id/page4" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="@string/Page4"
    android:textSize="20sp"
    android:layout_alignParentBottom="true"
    android:layout_alignParentRight="true"
    android:onClick="page4ButtonClick" />
<Button 
    android:id="@+id/page3" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="@string/Page3"
    android:textSize="20sp"
    android:layout_alignParentBottom="true"
    android:layout_toLeftOf="@+id/page4"
    android:onClick="page3ButtonClick" />
<Button 
    android:id="@+id/page2" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="@string/Page2"
    android:textSize="20sp"
    android:layout_alignParentBottom="true"
    android:layout_toLeftOf="@+id/page3" 
    android:onClick="page2ButtonClick"/>
<Button 
    android:id="@+id/page1" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="@string/Page1"
    android:textSize="20sp"
    android:layout_alignParentBottom="true"
    android:layout_toLeftOf="@+id/page2"
    android:onClick="page1ButtonClick" />

<TextView
    android:id="@+id/qr_code_label"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:text="@string/qr_code_label" />

<Button
    android:id="@+id/imageButton"
    style="?android:attr/buttonStyleSmall"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:onClick="onImageButtonClick"
    android:text="@string/image" />

<Button
    android:id="@+id/qrButton"
    style="?android:attr/buttonStyleSmall"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_toRightOf="@+id/imageButton"
    android:onClick="onQRButtonClick"
    android:text="@string/qr" />
<GridView 
    android:id="@+id/gridView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"

    android:columnWidth="80dp"
    android:gravity="center_horizontal"
    android:layout_centerInParent ="true"
    android:layout_marginTop="150dp"
    android:verticalSpacing="0dp"
    android:horizontalSpacing="0dp"
    android:numColumns="2"
    android:stretchMode="columnWidth"
    android:background="@color/peach"
    android:visibility="invisible"
    >
</GridView>



    </RelativeLayout>

And this is the function where i am calling web service and inserting data

    private ArrayList<String> callService()
{
    ArrayList<String> devices;
    devices=new ArrayList<String>();
    try
    {
        ODataConsumer con=ODataJerseyConsumer.create("url of web service");
        List<OEntity> listEntities = con.getEntities("Devices").execute().toList();
        if (listEntities.size() > 0)
        {

           for (OEntity entity : listEntities)
           {

               devices.add(entity.getProperty("Name").getValue().toString());


           }            
         }

        String[] devices_list= new String[devices.size()];
        devices_list = devices.toArray(devices_list);
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, devices_list);

        mGrid.setAdapter(adapter);
    }
    catch(Exception e)
    {

    }

    return devices;
 }      

And in another function i am setting the visibility of grid view to visible. This is being done in UI thread. Grid view is appearing, but not having any data, its coming as a small bar.

Please help me as i am new to android..

Answer 1

change android:layout_width and android:layout_height to fill_parent. try like this.

<GridView
    android:id="@+id/gridView1"
    android:numColumns="3"
    android:gravity="center"
    android:columnWidth="50dp"
    android:stretchMode="columnWidth"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

</GridView>

Tell me if it doesn't work ;)