Repeat steps 5 - 7 for as many custom directories as you desire.

Put the XML files you want inside the new 'layout' directory from the backup you made on your desktop.

(Note: This MUST be named 'layout'!!! very important).

Right click the 'fragment' or 'activities' directory (Note: this doesn't have to be 'fragment' or 'activities' that's just what i'm using as an example) and select new > directory once again and name this directory 'layout'.(This will be the name of the type of XML files you will have in it, for example, 'fragments' and 'activities'). Right click the new 'layouts' directory and select new > directory.(This can be whatever you want, but it will not be a 'fragment' directory or 'activity' directory, that comes later). Right click the res directory and select new > directory.Delete the entire layout directory (Make sure you backed everything up from step 1!!!).Copy all of the XML files out of your layout directory, and put them into a directory on the desktop or something for backup.This is how I got mine to work with an already built project. (Note: This will only work and look like separate directories inside the 'project' view, not the 'android' view unfortunately.) Here is the code of my mainActivity.java: package just wanted to add onto eskis' fantastic answer for people having trouble.

Then for the calculation, I searched the ArrayList for the operator and took the numbers that are to left and to the right of it, and replaced those with the answer of those. My main idea was to have an ArrayList in wich every number and every operator gets stored. can take multiple digits and floating point numbers as input.For my first project, I made a basic calculator app. I recently decided to try some app development with Android Studio and Java. I'm a college student in my first year of my bachelor in IT.

Android studio java subfolders