How to set a simple adapter to listview?

Prady picture Prady · Apr 11, 2012 · Viewed 29.5k times · Source

I have problem adding arraylist to list view, will explain about my problem here.. tell me what is wrong here... I have three linear layouts, and in the middle layout i have list view, as shown in the xml file below.. `

 <LinearLayout
    android:id="@+id/linearLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_weight="0.59"
        android:src="@drawable/x_title" />

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button" />
</LinearLayout>

<LinearLayout
    android:id="@+id/linearLayout_grouplist"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="0.09"
    android:orientation="vertical"
    android:weightSum="1" >

    <ListView
        android:id="@+id/listview_grouplist"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" >
    </ListView>

</LinearLayout>

<LinearLayout
    android:id="@+id/linearLayout2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <Button
        android:id="@+id/button4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="0.39"
        android:text="TextView" />

    <Button
        android:id="@+id/button5"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button" />
  </LinearLayout>
</LinearLayout>`

when I try to add items to the list with array adapter, its working fine for me..but its not working for List Adapter. It is crashing.

ListAdapter adapter = new SimpleAdapter(this,
      mylist, 
      R.layout.grouplistlayout, 
      new String[] { "Group Name" }, 
      new int[] { R.id.listview_grouplist });

String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
      "Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
      "Linux", "OS/2" };

ArrayAdapter<String> adapter1 = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, values);
lst_projlist.setAdapter(adapter1);

could someone tell me what is missing here ?

Answer

Barak picture Barak · Apr 11, 2012

Your problem is in here:

    R.layout.grouplistlayout,
    new int[] { R.id.listview_grouplist }); 

The top one should be pointing to a list layout, like android.R.layout.simple_list_item_1 The bottom one should be pointing to to a TextView, not a list view.

Also, I don't see where you are binding the adapter to the listview.

From the SimpleAdapter docs:

public SimpleAdapter(Context context, 
                     List<? extends Map<String, ?>> data, 
                     int resource, 
                     String[] from, 
                     int[] to)

Since: API Level 1

Constructor

Parameters
context The context where the View associated with this SimpleAdapter is running
data A List of Maps. Each entry in the List corresponds to one row in the list. The Maps contain the data for each row, and should include all the entries specified in "from"
resource Resource identifier of a view layout that defines the views for this list item. The layout file should include at least those named views defined in "to"
from A list of column names that will be added to the Map associated with each item.
to The views that should display column in the "from" parameter. These should all be TextViews. The first N views in this list are given the values of the first N columns in the from parameter.