Creating ListView that has RadioButton in ListView custom item.
Here are the key ideas
- when a
RadioButton
is checked we must call notifyDataSetChanged()
, so that all views get updated.
- when a
RadioButton
is checked we must set a selectedPosition
, to keep track of which RadioButton
is selected
View
s are recycled inside ListView
s. Therefore, their absolute position changes in the ListView
. Therefore, inside ListAdapter#getView()
, we must call setTag()
on each RadioButton
. This allows us to determine the current position of the RadioButton
in the list when the RadioButton
is clicked.
RadioButton#setChecked()
must be updated inside getView()
for new or pre-existing View
s.
1.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="wrap_content"
android:id="@+id/ll_parent">
<RadioButton
android:id="@+id/radio"
android:layout_width="match_parent"
android:layout_height="50dp"
android:clickable="false"/>
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:clickable="false"/>
</LinearLayout>
To make RadioButton works correctly when click, you need to set
android:clickable="false" to child elements.
2.activity_list_view_custom_item_with_radio_button.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ListView
android:id="@+id/listView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:choiceMode="singleChoice"/>
</LinearLayout>
3.ListViewCustomItemWithRadioButtonActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.RadioButton;
import android.widget.TextView;
import java.util.ArrayList;
public class ListViewCustomItemWithRadioButtonActivity extends AppCompatActivity {
private int selected_pos = -1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list_view_custom_item_with_radio_button);
ListView listView = (ListView) findViewById(R.id.listView);
ArrayList<String> arrayList = new ArrayList<>();
for (int i = 0 ; i < 50; i++){
arrayList.add("Item : " + (i + 1));
}
MyAdapter arrayAdapter = new MyAdapter(arrayList);
listView.setAdapter(arrayAdapter);
}
private class MyAdapter extends BaseAdapter {
private ArrayList< String>arrayList;
private MyAdapter(ArrayList< String>arrayList){
this.arrayList = arrayList;
}
@Override
public int getCount() {
return arrayList.size();
}
@Override
public Object getItem(int position) {
return arrayList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = convertView;
if (view == null){
view = View.inflate(ListViewCustomItemWithRadioButtonActivity.this, R.layout.row, null);
}
final LinearLayout ll_parent = (LinearLayout) view.findViewById(R.id.ll_parent);
final RadioButton radioButton = (RadioButton) view.findViewById(R.id.radio);
radioButton.setText(arrayList.get(position));
radioButton.setChecked(position == selected_pos);
radioButton.setTag(position);
ll_parent.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
selected_pos = (Integer) v.findViewById(R.id.radio).getTag();
notifyDataSetChanged();
}
});
TextView textView = (TextView) view.findViewById(R.id.text);
textView.setText("Position : ".concat(String.valueOf(position)));
return view;
}
}
}