How to show an Android Activity as a Dialog

It’s possible to show an Activity as a Dialog. All we need to do is use a Dialog theme for the android:theme attribute in the AndroidManifest.xml file. You can use any Dialog theme.

<activity
android:name="com.example.demoapp.MainActivity"
android:label="@string/title_dialog_activity"
android:theme="@android:style/Theme.Holo.Light.Dialog" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

But the dialog will cancel if you touch outside. To prevent this use setFinishOnTouchOutside(false) in the onCreate method of the activity.