<resources>

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

        <item name="android:windowBackground">@color/white</item>
        <item name="android:colorBackground">@color/white</item>
    </style>

    <style name="MyDialogTheme" parent="Theme.AppCompat.Light.Dialog.Alert">
        <item name="android:background">@color/white</item>
    </style>

</resources>

<resources>

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

        <item name="android:windowBackground">@color/white</item>
        <item name="android:colorBackground">@color/white</item>

        <item name="android:windowFullscreen">true</item>
    </style>

    <style name="MyDialogTheme" parent="Theme.AppCompat.Light.Dialog.Alert">
        <item name="android:background">@color/white</item>
    </style>

</resources>

Make the app full screen
Make the app full screen

