This code works in basic Activity, but it doesn't in Tabbed activity. I want to use the ListView with custom view. Common code:
list_row.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="@+id/textView2" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Medium Text"
android:id="@+id/textView3" />
</LinearLayout>
It is my simple data class, I want to show it:
String nev;
String szakma;
public String getNev() {
return nev;
}
public void setNev(String nev) {
this.nev = nev;
}
public String getSzakma() {
return szakma;
}
public void setSzakma(String szakma) {
this.szakma = szakma;
}
public Adat(String nev, String szakma) {
this.nev = nev;
this.szakma = szakma;
}
And my custom ListAdapter:
public class EgyeniAdapter extends BaseAdapter {
Context context;
ArrayList<Adat> adatok;
public EgyeniAdapter(Context context, ArrayList<Adat> adatok) {
this.context = context;
this.adatok = adatok;
}
@Override
public int getCount() {
return adatok.size();
}
@Override
public Object getItem(int position) {
return adatok.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_row,null); // itt rendelem hozza a saját viewet
if (convertView != null)
{
TextView Cim = (TextView) convertView.findViewById(R.id.textView2);
TextView Alcim = (TextView) convertView.findViewById(R.id.textView3);
Adat adatom = adatok.get(position);
Cim.setText(adatom.getNev());
Alcim.setText(adatom.getSzakma());
}
return convertView;
}
}
And it is my MainActivity:
@Override
protected void onCreate(Bundle savedInstanceState) {
...
betolt();
}
private void betolt()
{
ArrayList<Adat> adataim = new ArrayList<>();
adataim.add(new Adat("Title","Subtitle"));
adataim.add(new Adat("Title2","Subtitle2"));
final ListView myList= (ListView) findViewById(R.id.listView);
EgyeniAdapter egyeniAdapter = new EgyeniAdapter(this,adataim);
myList.setAdapter(egyeniAdapter);
}
This works, but when I want use it in another application in Tabbed activity, it throws:
NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
What is the problem?
My fragment code:
<FrameLayout 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"
tools:context="com.example.mpet8.englishtest.Tesztek">
<!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="@string/hello_blank_fragment"
android:id="@+id/tesztek_label"
/>
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/tesztek_listView"
android:layout_gravity="left|top" />
</FrameLayout>
I call my method in onStart method:
@Override
protected void onStart() {
super.onStart();
betolt();
}
