ShareActionProvider implementation using v7 Appcompat library.

This example explains how to implement effective share action in your actionbar using ShareActionProvider class. ActionProvider is made available since Android 4.0 (API Level 14), But to have a share widget in older versions (Android 2.1 and higher) we will use appcompat library. An ActionProvider, once attached to a menu item in the action bar, handles both the appearance and behavior of that item. In the case of ShareActionProvider, you provide a share intent and it does the rest.

Specifying The Action Provider Class

To use the ShareActionProvider, add http://schemas.android.com/apk/res-auto schema to your menu items XML. set the actionProviderClass attribute on a menu item in the XML for the Action Bar’s menu.

 <menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools" >
    <item
        android:id="@+id/action_share"
        app:actionProviderClass="android.support.v7.widget.ShareActionProvider"
        app:showAsAction="always"
        android:title="Share" />
</menu>

Update your mainActivity to create shareActionProvider

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.MenuItemCompat;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.ShareActionProvider;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends ActionBarActivity {
    private ShareActionProvider mShareActionProvider;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        // Get the menu item.
        MenuItem menuItem = menu.findItem(R.id.action_share);
        // Get the provider and hold onto it to set/change the share intent.
        mShareActionProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(menuItem);
        // Set share Intent.
        // Note: You can set the share Intent afterwords if you don't want to set it right now.
        mShareActionProvider.setShareIntent(createShareIntent());
        return true;
    }

    // Create and return the Share Intent
    private Intent createShareIntent() {
        Intent shareIntent = new Intent(Intent.ACTION_SEND);
        shareIntent.setType("text/plain");
        shareIntent.putExtra(Intent.EXTRA_TEXT, "http://droiddevguide.blogspot.ae/");
        return shareIntent;
    }

    // Sets new share Intent.
    // Use this method to change or set Share Intent in your Activity Lifecycle.
    private void changeShareIntent(Intent shareIntent) {
        mShareActionProvider.setShareIntent(shareIntent);
    }
}

Output: