App Crashes On Startup Due To java.lang.UnsupportedOperationException: addView(View, LayoutParams) is not supported in AdapterView

Question

My app crashes every time I start it in the emulator. Here is the logcat:

01-02 17:20:58.859: ERROR/AndroidRuntime(249): Uncaught handler: thread main exiting due to uncaught exception

01-02 17:20:58.889: ERROR/AndroidRuntime(249): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.shoppinglist/com.shoppinglist.ShoppingList}: java.lang.UnsupportedOperationException: addView(View, LayoutParams) is not supported in AdapterView

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.app.ActivityThread.access$2100(ActivityThread.java:116)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.os.Handler.dispatchMessage(Handler.java:99)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.os.Looper.loop(Looper.java:123)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at android.app.ActivityThread.main(ActivityThread.java:4203)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at java.lang.reflect.Method.invokeNative(Native Method)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at java.lang.reflect.Method.invoke(Method.java:521)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)

01-02 17:20:58.889: ERROR/AndroidRuntime(249):     at dalvik.system.NativeStart.main(Native Method)**

Here is my .java file:

package com.shoppinglist;

import android.app.ListActivity;
import android.app.Dialog;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class ShoppingList extends ListActivity {
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    Button button1main = (Button) findViewById(R.id.Button01main);
     button1main.setOnClickListener(new OnClickListener()  {
     @Override
      public void onClick(View v)  {
       final Dialog dialog = new Dialog(ShoppingList.this);
       dialog.setContentView(R.layout.maindialog);
       dialog.setCancelable(true);
       Button button = (Button) dialog.findViewById(R.id.cancel);
       button.setOnClickListener(new OnClickListener()  {
        @Override
         public void onClick(View v)  {
          dialog.dismiss();
        }
        });
       dialog.show();
       }
     });
    }
}

My layout.xml:

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFCC00"
    android:padding="10dp"
    android:id="@+id/listview">
        <Button
            android:id="@+id/Button01main"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
   android:text="Add item..."/>
</ListView> 

My dialog xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:id="@+id/layout_root"
  android:orientation="vertical"
  android:background="#FFFFFF"
  android:minHeight="100dp"
  android:minWidth="300dp">
  <EditText
    android:id="@+id/edittext"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:hint="Type the name of an item here...">
   </EditText>
 <LinearLayout
  android:id="@+id/button_layout"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="horizontal"
  android:layout_gravity="right">
  <Button
   android:id="@+id/ok"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:text="OK"
   android:layout_gravity="bottom">
   </Button>
  <Button
   android:id="@+id/cancel"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:text="Cancel"
   android:layout_gravity="bottom">
   </Button>
  </LinearLayout> 
</LinearLayout>

Any help will be appreciated. I need code samples for fixes, I am not very experienced.

Answer 1

In your layout xml, you're trying to add a button inside a ListView. The ListView is an AdapterView , as the error says, so it must be populated by an adapter which provides a list of similar 'things' - these could be a list of strings (from an array list) or a list of custom views which you create, but they are all basically the same type of thing - you cant, for instance, add a button, then to another one add a string. Create an adapter to provide the things you want in your ListView.