Creating a ContextMenu on a ListView
What you learn: You will learn how to create a ContextMenu on a ListView. This can easily be applied to other situations.
Difficulty: 2 of 5


What it will look like:

Description:
The Context-Menu gets visible when long-pressing an entry in the ListView.
Layout: "/res/main.xml"
Using xml Syntax Highlighting
- <?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="Long-Press on of the Items in the list." />
- <ListView android:id="@+id/list_favorites"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"/>
- </LinearLayout>
Parsed in 0.001 seconds, using GeSHi 1.0.8.4
We will create a ListView that gets filled by a list of a custom Class (Favorite). In the ContextMenu we will offer the user a possibility to delete the entry he long-pressed.
Using java Syntax Highlighting
- package org.anddev.contextmenusample;
- import java.util.ArrayList;
- import android.app.Activity;
- import android.os.Bundle;
- import android.view.ContextMenu;
- import android.view.View;
- import android.view.Menu.Item;
- import android.view.View.OnPopulateContextMenuListener;
- import android.widget.ArrayAdapter;
- import android.widget.ListView;
- import android.widget.AdapterView.ContextMenuInfo;
- public class ContextMenuSample extends Activity {
- // ===========================================================
- // Final Fields
- // ===========================================================
- protected static final int CONTEXTMENU_DELETEITEM = 0;
- // ===========================================================
- // Fields
- // ===========================================================
- protected ListView mFavList;
- protected ArrayList<Favorite> fakeFavs = new ArrayList<Favorite>();
- // ===========================================================
- // "Constructors"
- // ===========================================================
- /** Called when the activity is first created. */
- @Override
- public void onCreate(Bundle icicle) {
- super.onCreate(icicle);
- setContentView(R.layout.main);
- /* Add some items to the list the listview will be showing. */
- fakeFavs.add(new Favorite("John", "nice guy"));
- fakeFavs.add(new Favorite("Yasmin", "hot girl"));
- fakeFavs.add(new Favorite("Jack", "cool guy"));
- this.mFavList = (ListView) this.findViewById(R.id.list_favorites);
- initListView();
- }
- private void refreshFavListItems() {
- mFavList.setAdapter(new ArrayAdapter<Favorite>(this,
- android.R.layout.simple_list_item_1, fakeFavs));
- }
- private void initListView() {
- /* Loads the items to the ListView. */
- refreshFavListItems();
- /* Add Context-Menu listener to the ListView. */
- mFavList.setOnPopulateContextMenuListener(new OnPopulateContextMenuListener() {
- @Override
- public void onPopulateContextMenu(ContextMenu conMenu, View arg1, Object arg2) {
- conMenu.setHeader("ContextMenu");
- conMenu.add(0, CONTEXTMENU_DELETEITEM, "Delete this favorite!");
- /* Add as many context-menu-options as you want to. */
- }
- });
- }
- // ===========================================================
- // Methods from SuperClass/Interfaces
- // ===========================================================
- @Override
- public boolean onContextItemSelected(Item aItem) {
- ContextMenuInfo menuInfo = (ContextMenuInfo) aItem.getMenuInfo();
- /* Switch on the ID of the item, to get what the user selected. */
- switch (aItem.getId()) {
- case CONTEXTMENU_DELETEITEM:
- /* Get the selected item out of the Adapter by its position. */
- Favorite favContexted = (Favorite) mFavList.getAdapter()
- .getItem(menuInfo.position);
- /* Remove it from the list.*/
- fakeFavs.remove(favContexted);
- refreshFavListItems();
- return true; /* true means: "we handled the event". */
- }
- return false;
- }
- // ===========================================================
- // Inner and Anonymous Classes
- // ===========================================================
- /** Small class holding some basic */
- protected class Favorite {
- protected String name;
- protected String kindness;
- protected Favorite(String name, String kindness) {
- this.name = name;
- this.kindness = kindness;
- }
- /** The ListView is going to display the toString() return-value! */
- public String toString() {
- return name + " (" + kindness + ")";
- }
- public boolean equals(Object o) {
- return o instanceof Favorite && ((Favorite) o).name.compareTo(name) == 0;
- }
- }
- }
Parsed in 0.017 seconds, using GeSHi 1.0.8.4
That's it 

Regards,
plusminus