Question

I’ve this layout xml, named pagina.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_vertical" >

    <TextView
        android:id="@+id/descrizione"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <Button
        android:id="@+id/scelta1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="Button" />

    <Button
        android:id="@+id/scelta3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/scelta1"
        android:layout_alignLeft="@+id/scelta1"
        android:layout_marginBottom="16dp"
        android:text="Button" />

    <Button
        android:id="@+id/scelta2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/scelta3"
        android:layout_alignLeft="@+id/scelta3"
        android:layout_marginBottom="18dp"
        android:text="Button" />

</RelativeLayout>

I want to write the description of the element, but when I assign to a variable the textview element, the emulator crashes. This is the code:

public int posizione;
    public String stanza;
    public string[] azioni;
    public int[] vai;
    public XmlPullParser xpp;
    public EditText descr;
    public Button scelta_1, scelta_2, scelta_3;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pagina);

        try {
            carica_stanza(posizione);
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (XmlPullParserException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        descr = (EditText) this.findViewById(R.id.descrizione);
        scelta_1= (Button) this.findViewById(R.id.scelta1);
        scelta_2= (Button) this.findViewById(R.id.scelta2);
        scelta_3= (Button) this.findViewById(R.id.scelta3);

    }

Help me to understand!

Answer 1

Try

public TextView descr;
// ...
descr = (TextView) this.findViewById(R.id.descrizione);

instead of

public EditText descr;
// ...
descr = (EditText) this.findViewById(R.id.descrizione);

You are using TextView in xml layout. But you tried to cast this object to EditText

What are you going to use? If you want this text to be editable you need to change your component to EditText in xml and in your class.

• TextView – just prints text
• EditText – lets you to edit text in program