How to set the theme for DialogFragment

Question

Can someone please explain why this statement works perfectly well:

setStyle(DialogFragment.STYLE_NO_TITLE, android.R.style.Theme_Holo); 

and the next statement does not deliver

setStyle(DialogFragment.STYLE_NO_TITLE, R.style.dialog); 

This is what I have in the style's department:

<style     name="dialog">     <!-- title encapsulating main part (backgroud) of custom alertdialog -->     <item         name="android:windowFrame">@null</item>         <!-- turn off any drawable used to draw a frame on the window -->     <item         name="android:windowBackground">@null</item>         <!-- turn off any drawable used to draw a frame on the window -->     <item         name="android:windowIsFloating">true</item>         <!-- float the window so it does not fill the screen -->     <item         name="android:windowNoTitle">true</item>         <!-- remove the title bar we make our own-->     <item         name="android:windowContentOverlay">@null</item>         <!-- remove the shadow from under the title bar --> </style> 

Answer 1

Try using the code in onCreate of the fragment as

@Override public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);              setStyle(DialogFragment.STYLE_NO_TITLE, R.style.dialog); } 

Answer 2

https://stackoverflow.com/a/24375599/2898715 it's also possible to omit the setStyle call altogether, and define the defulat style that DialogFragments will use throughout the whole app.

styles.xml

<?xml version="1.0" encoding="utf-8"?> <resources>      <style name="AppTheme" parent="android:Theme.Holo.Light">         <!-- makes all dialogs in your app use your dialog theme by default -->         <item name="alertDialogTheme">@style/DialogTheme</item>         <item name="android:alertDialogTheme">?alertDialogTheme</item>         <item name="dialogTheme">?alertDialogTheme</item>         <item name="android:dialogTheme">?alertDialogTheme</item>     </style>      <!-- define your dialog theme -->     <style name="DialogTheme" parent="Theme.AppCompat.DayNight.Dialog.MinWidth">         <item name="android:buttonStyle">@style/button_green</item>         <item name="android:textColorHint">@color/green</item>     </style>  </resources> 

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android">     .....     <application android:theme="@style/AppTheme">         .....     </application> </manifest>