Q:

How do you display a string on Android?

Edit: it turned out the XML Viewer wasn't the emulator, and does not actually run code.
So, I'm starting my first app in Android Studio 1.1.0, and I realized that I can't even manage to display a string (created in the java file).
I did all research I could, but no matter what snippets of code I copy/paste, it never works.
I tried copy/pasting the snippet of code from the first answer here: Android Eclipse: Change the text in the app to a string created withing the program and it doesn't work. The findViewById method is in red, and so is my_text_view :
String displaythisgoddammit = "display this goddammit";
    private TextView text = (TextView) findViewById(R.id.my_text_view);
    text.setText(displaythisgoddammit);

And my textview (in activity_main.xml) is:
 <TextView
    android:id="@+id/my_text_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/displaythisgoddammit"/>

It can't find the string, no matter what I do. Apparently I must put it in the strings.xml file, but then how do I edit it...? In the question I linked, the snippet of code apparently worked for a string in the java file.
Here is my main file (I'm not sure if it's really relevant though, it's just snippets of code I copy/pasted): http://pastebin.com/7uuHyJWP I put the string at line 144, should I put it elsewhere?
Some help please? I've been researching for 5 hours but none of the solutions I tried work...

A:

The issue with your code is on the line when you use 
TextView text = (TextView) findViewById(id.my_text_view);

It is occuring because when you define a TextView or any other object by it's Id you need to use R.id.my_text_view.
So, to fix it simply change it to
TextView text = (TextView) findViewById(R.id.my_text_view);

