Android. Change font color for whole app programaticcaly

Question

I want to let user change the font size or color in android app under settings. I had an idea to make style, apply it to chosen elements and finally in code just change its value, but now I have no idea how to make it. My default style looks like this

 <style name="myTextStyle" parent="AppTheme">
     <item name="android:textColor">#FF0000</item>
     <item name="android:textSize">10sp</item>
 </style>

I don't know how to change the default theme/style of app programmatically. Plz help!

Answer 1

You can create different styles with different font colors. Then you can apply the style to activity based on user preferences (maybe stored in SharedPreferences).

public void onCreate(Bundle savedInstanceState) {

    setTheme(android.R.style.Theme);
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}