As you know every time you create new project with some activity Android Studio generates default activity_main.xml file with RelativeLayout as the root element and one TextView. But I prefer to use LinearLayout without any nested views. How can I change a way Android Studio generates default activity_main.xml?
You can do that by editing default template files, which are located in:
so for example, default layout file for template of EmptyActivity (note: this one is specific, the other ones have their own res folders) is located in:
by simply replacing RelativeLayout with LinearLayout in your favourite text editor, you get what you want, but instead of that, I recommend you to make your own template, where you can define literally anything, according to your desires.
Edit: For the BlankActivity and a guide how to edit the other templates see this link: How to change a BlankActivity template default files and a guide how to do it for any others.