ActionBarの共有ボタンに共有履歴を表示する方法 ref: http://qiita.com/nein37/items/cf5af57f4a313958631d

file0.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".MyActivity">
    <item
        android:id="@+id/action_share_always"
        android:actionProviderClass="android.widget.ShareActionProvider"
        android:showAsAction="always"
        android:title="@string/action_share" />
</menu>

file1.java

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.my, menu);

        // ShareActionProvider の設定
        MenuItem actionItem = menu.findItem(R.id.action_share_always);
        ShareActionProvider actionProvider = (ShareActionProvider) actionItem.getActionProvider();
        // インテントの設定
        Intent shareIntent = ShareCompat.IntentBuilder.from(this)
                .setText("hogehoge")
                .setType("text/plain")
                .getIntent();
        // ShareActionProviderにインテントの設定
        actionProvider.setShareIntent(shareIntent);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // 何も書かなくてOK
        return super.onOptionsItemSelected(item);
    }

file2.xml

<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"
    tools:context=".MyActivity">
    <item
        android:id="@+id/action_share_always"
        android:icon="@android:drawable/ic_menu_share"
        android:title="共有"
        app:showAsAction="always" />
</menu>

file3.java

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.my, menu);

        // IntentBuilderの生成
        ShareCompat.IntentBuilder builder = ShareCompat.IntentBuilder.from(this);
        builder.setText("hogehoge")
                .setType("text/plain");
        // MenuItemにShareアクションの設定
        ShareCompat.configureMenuItem(menu, R.id.action_share_always, builder);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        return super.onOptionsItemSelected(item);
    }