Contextual Action Mode in android

In this tutorial we will learn, how to activate the contextual action mode, which is very similar to the floating context menu, but shows the menu options in the action bar instead of a pop up menu. We will activate this contextual action menu on a long click, by setting an onLongClickListener on our View. We will set it’s title and implement an ActionMode.Callback interface, in which we then override the oncreateActionMode, onPrepareActionMode, onActionItemClicked and onDestroyActionMode methods. There we inflate our app bar menu with our own menu xml file and handle click events on the single menu items.
Lastly we will learn, how to change the color of our action mode app bar and how to prevent it from pushing our toolbar away, instead of displaying on top of it, by using the windowActionBarOverlay attribute in our styles.xml file.



In activity_main.xml file add these lines of codes:-


<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        android:textSize="30sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


</android.support.constraint.ConstraintLayout>

In res file add a directory menu within these directory add a file example_menu.xml within this file add this line of code :-

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/option_1"
        android:icon="@drawable/ic_delete"
        android:title="Option 1" />

    <item
        android:id="@+id/option_2"
        android:icon="@drawable/ic_share"
        android:title="Option 2" />


</menu>

In  MainActivity.java  class file add these lines of codes:-

public class MainActivity extends AppCompatActivity {
    private ActionMode mActionMode;

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

        TextView textView = findViewById(R.id.text_view);
        textView.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                if (mActionMode != null) {
                    return false;
                }

                mActionMode = startSupportActionMode(mActionModeCallback);
                return true;
            }
        });
    }

    private ActionMode.Callback mActionModeCallback = new ActionMode.Callback() {
        @Override
        public boolean onCreateActionMode(ActionMode mode, Menu menu) {
            mode.getMenuInflater().inflate(R.menu.example_menu, menu);
            mode.setTitle("Choose your option");
            return true;
        }

        @Override
        public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
            return false;
        }

        @Override
        public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
            switch (item.getItemId()) {
                case R.id.option_1:
                    Toast.makeText(MainActivity.this, "Option 1 selected", Toast.LENGTH_SHORT).show();
                    mode.finish();
                    return true;
                case R.id.option_2:
                    Toast.makeText(MainActivity.this, "Option 2 selected", Toast.LENGTH_SHORT).show();
                    mode.finish();
                    return true;
                default:
                    return false;
            }
        }

        @Override
        public void onDestroyActionMode(ActionMode mode) {
            mActionMode = null;
        }
    };
}


Under res folder within styles.xml file add these lines of codes:-

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>

        <item name="actionModeBackground">@color/colorPrimary</item>
        <item name="windowActionBarOverlay">true</item>
    </style>


</resources>


Now, run the code on your emulator and see the output of contextual action menu on action bar in android.