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androidlistviewlogcat

Android listview trouble


I'm having problems trying to run an Android activity which implements a ListView, fills it with 20 elements and displays it: the activity crashes upon launch.

Here are the relevant LogCat errors:

You must supply a resource ID for a TextView
FATAL EXCEPTION: main
java.lang.IllegalStateException: ArrayAdapter requires the resource ID to be a TextView
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:386)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
at android.widget.AbsListView.obtainView(AbsListView.java:2177)
at android.widget.ListView.measureHeightOfChildren(ListView.java:1247)
at android.widget.ListView.onMeasure(ListView.java:15848)
at android.widget.RelativeLayout.measureChild(RelativeLayout.java:698)
at android.widget.RelativeLayout.onMeasure(ListView.java:1159)
at android.view.View.measure(View.java:15848)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.app.ActivityThread.main(ActivityThread.java:5013)
Caused by: java.lang.ClassCastException: android.widget.ListView cannot be cast to android.widget.TextView.
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:382)

ThirdActivity.java

package com.example.logger;

import android.os.Bundle;
import android.app.Activity;
import android.app.ListActivity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

public class ThirdActivity extends ListActivity implements OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_third);
        final ListView listview = (ListView) findViewById(android.R.id.list);
        String[] values = new String[] {"One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten", 
                "Eleven", "Twelve", "Thirteen", "Fourteen", "Fifteen", "Sixteen", "Seventeen", "Eighteen", "Nineteen",
                "Twenty"};
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.activity_third, android.R.id.list, values);
        setListAdapter(adapter);


    }

        @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.third, menu);
        return true;

        }

        public void attachButton()
        {
            findViewById(R.id.add).setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

        }
}

End .java

And the layout:

Activity_third.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".ThirdActivity" >

   <Button
       android:id="@+id/add"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_alignParentTop="true"
       android:text="@string/add"
       />

   <ListView 
       android:id="@android:id/list"
       android:layout_width="match_parent"
       android:layout_below="@+id/add"
       android:layout_height="wrap_content"

          ></ListView>

</RelativeLayout>

End .xml

Could you please tell me what I need to change to get it to work based on the LogCat error logs?

Thank you very much for your help.

Yours sincerely,

Mauro.


Solution

  • ArrayAdapter requires the resource ID to be a TextView

    This just means, that you have to supply a layout with a TextView as an argument. The Adapter will bind this TextView to your data. But you are currently passing in your layout with your ListView in it.

    So change this:

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.activity_third, android.R.id.list, values);
    

    to this:

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