In android, Context Menu is like a floating menu and that appears when the user performs a long press or click on an element and it is useful to implement actions that affect the selected content or context frame.
The android Context Menu is more like the menu which displayed on right-click in Windows or Linux.
Following is the pictorial representation of using Context Menu in our android applications.
In android, the Context Menu offers actions that affect a specific item or context frame in the UI and we can provide a context menu for any view. The context menu won’t support any item shortcuts and item icons.
The views which we used to show the context menu on long-press, we need to register that views using registerForContextMenu(View) in our activity and we need to override onCreateContextMenu() in our activity or fragment.
When the registered view receives a long-click event, the system calls our onCreateContextMenu() method. By using the onCreateContextMenu() method, we can create our menu items as shown below.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.btnShow);
registerForContextMenu(btn);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.setHeaderTitle("Context Menu");
menu.add(0, v.getId(), 0, "Upload");
menu.add(0, v.getId(), 0, "Search");
}
If you observe above code, we registered our Button control using registerForContextMenu() to show the context menu on button long-click and binding the Context Menu items using onCreateContextMenu() method.
In android, we can handle a context menu item click events using the onContextItemSelected() method.
Following is the example of handling a context menu item click event using onContextItemSelected() method.
@Override
public boolean onContextItemSelected(MenuItem item) {
if (item.getTitle() == "Save") {
// do your coding
}
else {
return false;
}
return true;
}
Note: If you are using Android 3.0 +, the Context Menu won’t support any item shortcuts and item icons in the menu.
Following is the example of implementing a Context Menu in android application.
Create a new android application using android studio and give names as ContextMenuExample. In case if you are not aware of creating an app in android studio check this article Android Hello World App.
Now open an activity_main.xml file from \res\layout path and write the code like as shown below
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="@+id/btnShow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Long press me"
android:layout_marginTop="200dp" android:layout_marginLeft="100dp"/>
</LinearLayout>
If you observe above code we created a one Button control in XML Layout file to show the context menu when we do long press on Button.
Once we are done with the creation of layout with required control, we need to load the XML layout resource from our activity onCreate() callback method, for that open main activity file MainActivity.java from \java\com.tutlane.contextmenuexample path and write the code like as shown below.
package com.tutlane.contextmenuexample;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.btnShow);
registerForContextMenu(btn);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.setHeaderTitle("Context Menu");
menu.add(0, v.getId(), 0, "Upload");
menu.add(0, v.getId(), 0, "Search");
menu.add(0, v.getId(), 0, "Share");
menu.add(0, v.getId(), 0, "Bookmark");
}
@Override
public boolean onContextItemSelected(MenuItem item) {
Toast.makeText(this, "Selected Item: " +item.getTitle(), Toast.LENGTH_SHORT).show();
return true;
}
}
If you observe above code we are overriding onCreateContextMenu() method in activity to create context menu and registered view for context menu using registerForContextMenu().
Generally, during the launch of our activity, onCreate() callback method will be called by android framework to get the required layout for an activity.
When we run above example using an android virtual device (AVD) we will get a result like as shown below.
This is how we can create Context Menu in android applications to show the menu list when the user long press on the defined element in our application.