On the line: lv = (ListView) findViewById(R.id.list); You are trying to get a handle on a ListView that does not exist in the XML that you are showing.
On Aug 12, 1:34 pm, Warrior <[email protected]> wrote: > can anyone tell me whats wrong or suggest the best way to populate a > ListView on runtime from one screen to another. > Please see my code below > 1. the list always ends up empty > 2. I get a invalid resource error in the end. > > <?xml version="1.0" encoding="utf-8"?> > <LinearLayout xmlns:android="http://schemas.android.com/apk/res/ > android" > android:orientation="vertical" > android:layout_width="fill_parent" > android:layout_height="fill_parent" > > <TextView > android:layout_width="fill_parent" > android:layout_height="wrap_content" android:text="@string/hello" /> > <EditText > android:id="@+id/entry" android:layout_width="fill_parent" > android:layout_height="wrap_content" > android:background="@android:drawable/editbox_background"/> > <Button android:id="@+id/ok" > android:layout_width="wrap_content" > android:layout_height="wrap_content" android:layout_below="@id/ > entry" android:layout_alignParentRight="true" > android:layout_marginLeft="10dip" android:text="Add to List" /> > <Button android:id="@+id/viewlist" > android:layout_width="wrap_content" > android:layout_height="wrap_content" > android:layout_below="@id/ok" > android:layout_alignParentRight="true" > android:layout_marginLeft="10dip" > android:text="View List" /> > </LinearLayout> > > public class HelloWorld extends Activity { > > /** Called when the activity is first created. */ > > public ListView lv; > public ArrayList<String> arr = new ArrayList<String>(); > > @Override > public void onCreate(Bundle savedInstanceState) { > super.onCreate(savedInstanceState); > setContentView(R.layout.main); > > Button okButton = (Button) findViewById(R.id.ok); > okButton.setOnClickListener(new View.OnClickListener() { > public void onClick(View v) { > EditText et = (EditText) findViewById(R.id.entry); > arr.add(et.getText().toString()); > Toast.makeText(HelloWorld.this, "Added: " + et.getText(), > Toast.LENGTH_SHORT).show(); > et.bringToFront(); > } > }); > > Button viewListButton = (Button) findViewById(R.id.viewlist); > viewListButton.setOnClickListener(new View.OnClickListener() { > public void onClick(View v) { > setContentView(R.layout.text); > lv = (ListView) findViewById(R.id.list); > lv.setAdapter(new > ArrayAdapter<String>(HelloWorld.this, R.id.list, arr)); > } > }); > } > > > > } -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
