How to format an EditText's numeric value on unfocus (or at all!?) in Android to use commas

Question

I'm trying to take the user input, which may or may not have a comma in it, and put a comma in the correct places upon the user deselecting the field (or at all, if that's not possible).

I would also like to know how I can subtract the commas to make the number just an integer.

Thanks in advance for your help!

Answer 1

I don't know about Android specifically, but if you are programming in Swing then you probably want to look at javax.swing.InputVerifier. It triggers a verification check on a Swing component when it is unfocussed, which I believe includes the ability to modify the contents. An extra advantage is being able to check that the text field really does contain a number.

Answer 2

I don't know for certain but I can speculate. Add a focus listener and implement all the logic associated with modifying the content of the TextView in the listener.

As far as commas go, I assume you store the value as a String. So, you can use NumberFormat, parse the String and then call intValue method

NumberFormat format = NumberFormat.getNumberInstance();
String numAsStr = "1,000,000";
int num = format.parse(numAsStr).intValue();

You can use NumberFormat.format to format the input:

format.format(1000000)//will yield a string "1,000,000"