Android ListView with Checkboxes: How to capture checked items?
I have to do a ListView
with CheckBoxes
and then display the checked and unchecked items when user presses the button. The problem is I don't know how to do it, I manage to display the ListView
with the CheckBox
with this code:
package guestCheckBox.com;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
public class GuestCheckBox extends Activity {
private ListView lView;
ArrayList<String> guest= new ArrayList <String>();
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
lView = (ListView) findViewById(R.id.ListView01);
try{
URL url = new URL(
"http://tanjungrhu.jigsy.com/files/documents/Check.xml");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document开发者_如何学运维 doc = db.parse(new InputSource(url.openStream()));
doc.getDocumentElement().normalize();
NodeList words = doc.getElementsByTagName("Guest");
for(int i=0;i<words.getLength();i++){
Node node = words.item(i);
Element fstElmnt = (Element) node;
NodeList NameList = fstElmnt.getElementsByTagName("Name");
Element NameElement = (Element) NameList.item(0);
NameList = NameElement.getChildNodes();
guest.add((((Node) NameList.item(0)).getNodeValue()));
}
}
catch (Throwable t){
Toast.makeText(this, "Exeption:" + t.toString(), 2000).show();
}
//Set option as Multiple Choice. So that user can able to select more the one option from list
lView.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_multiple_choice, guest));
lView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
}
}
and here my main.xml
:
<?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" />
<ListView
android:id="@+id/ListView01"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
</ListView>
</LinearLayout>
Would somebody show me how can I do a buttons and how will I show the checked and unchecked items when the user presses that buttons?
I didn't completely understand what the problem is but I can provide you one useful extension of ListView which helps you manipulate with string data (set\get checked values):
public class MultipleChoiceListView extends ListView {
public MultipleChoiceListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public MultipleChoiceListView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MultipleChoiceListView(Context context) {
super(context);
}
@Override
public void setAdapter(ListAdapter adapter) {
throw new RuntimeException(
"This component doesn't support custom adapter. Use setData method to supply some data to show.");
}
/**
* Sets the data that should be displayed for choosing
*
* @param data List<String>
*/
public void setData(List<String> data) {
super.setAdapter(new ArrayAdapter<String>(getContext(), android.R.layout.simple_list_item_multiple_choice, data));
super.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
}
/**
* Sets the data that should be choosen by default
*
* @param checkedData List<String>
*/
public void setCheckedData(List<String> checkedData) {
for (int index = 0; index < getCount(); index++) {
if (checkedData.contains(getItemAtPosition(index))) {
setItemChecked(index, true);
}
}
}
/**
* Returns checked by the user data passed in {@link #setData(List)}
*
* @return List<String>
*/
public List<String> getCheckedData() {
SparseBooleanArray checked = getCheckedItemPositions();
List<String> checkedResult = new ArrayList<String>();
for (int i = 0; i < checked.size(); i++) {
if (checked.valueAt(i)) {
checkedResult.add(getAdapter().getItem(checked.keyAt(i)).toString());
}
}
return checkedResult;
}
}
Example of using:
private void initListMultiple() {
String[] data = new String[] {"first", "second", "third", "forth"};
String[] checkedData = new String[] {"second", "forth"};
multipleChoiceListView.setData(Arrays.asList(data));
multipleChoiceListView.setCheckedData(Arrays.asList(checkedData));
}
private void onTestListButtonClicked(View view) {
listResultTextView.setText(Arrays.toString(listView.getCheckedData().toArray()));
}
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