Your content must have a ListView whose id attribute is 'android.R.id.list' when extending ListActivity [duplicate]

Answer 1

You have defined a ListViewActivity (I guess), but it doesn't have a @android:id/list. You should change the ID of your ListView like this:

<ListView
  android:id="@android:id/list"
  android:layout_width="match_parent"
  android:layout_height="wrap_content" >
</ListView> 

Answer 2

Your problem is you are trying to extends ListActivity and you don't have a ListView with

android:id="android.R.id.list"

You need to have a ListView in your xml with that id. Please add it to your xml

You can tell by the following line in your logcat

Caused by: java.lang.RuntimeException: Your content must have a ListView whose id attribute is 'android.R.id.list'

If you find the next line that references your Activity it will tell you the class and line number

at testing.android.application.three.MainActivityNext.onCreate(MainActivityNext.java:28)

So MainActivityNext line 28 is showing the exception.

Note

As stated in a comment, please don't just post unformatted logcat when asking for help. Please try to look for where the error is occurring and post relevant code along with a description of what the problem is. This one was easy to see from the error but usually we will need to see some code

You can use CTRL+K to format your code and logcat or use the coding brackets above {}