How to make background Activity smaller while opening the Navigation Drawer?

Hey you can also give best effect for smaller activity . Check ResideMenu

demo with library.

You can perform this effect using the ActionBarDrawerToggle in the support library v4.

All you have to do is to Override onDrawerSlide method to retrieve the opening % of the drawer menu, and then scale your FrameLayout where your fragment is placed in.

Example with code:

main_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">

    <FrameLayout android:id="@+id/content_frame"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>    

    <ListView android:id="@+id/left_drawer"
    android:layout_width="240dp"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:choiceMode="singleChoice"
    android:divider="@android:color/transparent"
    android:dividerHeight="0dp"/>

</android.support.v4.widget.DrawerLayout>

Now in your Activity which holds the Drawer:

public class ConfigurerActivity extends ActionBarActivity 
{
    private DrawerLayout mDrawerLayout;
    private ListView mDrawerList;
    private ActionBarDrawerToggle mDrawerToggle;
    private FrameLayout frame;
    private float lastScale = 1.0f;

    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_layout);

        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerList = (ListView) findViewById(R.id.left_drawer);
        frame = (FrameLayout) findViewById(R.id.content_frame);

        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.drawable.ic_drawer, R.string.acc_drawer_open, R.string.acc_drawer_close) 
        {            
            @SuppressLint("NewApi")
            public void onDrawerSlide(View drawerView, float slideOffset)
            {
                float min = 0.9f;
                float max = 1.0f;
                float scaleFactor = (max - ((max - min) * slideOffset));

                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) 
                {
                    frame.setScaleX(scaleFactor);
                    frame.setScaleY(scaleFactor);
                }
                else
                {               
                    ScaleAnimation anim = new ScaleAnimation(lastScale, scaleFactor, lastScale, scaleFactor, frame.getWidth()/2, frame.getHeight()/2);
                    anim.setDuration(0);
                    anim.setFillAfter(true);
                    frame.startAnimation(anim);

                    lastScale = scaleFactor;
                }
            }
        };

        mDrawerLayout.setDrawerListener(mDrawerToggle);

        // ... more of your code
    }
}

Note that i use 2 different methods to scale, because setScaleX/Y are not available in PRE - Honeycomb Android versions.

With this, you can set your own scaleFactor (i think 0.9f its small enough) or maybe try new effects (change color) based on the opening % of the drawer.

Hope it helps.