Double parameter with 2 digits after dot in strings.xml?

lomza picture lomza · Mar 22, 2012 · Viewed 36.6k times · Source

I want to have a parameter in one string in strings.xml and this parameter should be a double value. So I use %1$f. Here - http://developer.android.com/reference/java/util/Formatter.html there are many examples, but what if I want to have have a few double/float parameters and I want only the second one to have 2 digits after .? I tried to use combinations like %2$.2f or %2.2$f. Nor of them worked. %.1f does not work as well. So, does anybody know how can I "customize" a float/double value inside a strings.xml? Thanks.

Answer

Nik Reiman picture Nik Reiman · Sep 24, 2015

Just adding to @David Airam's answer here; the "incorrect" solution he gives is actually correct, but with a bit of tweaking. The XML file should contain:

<string name="resource1">Hello string: %1$s, and hello float: %2$.2f.</string>

Now in the Java code:

String svalue = "test";
float sfloat= 3.1415926;
String sresult = getString(R.string.resource1, svalue, sfloat);

The exception that @David Airam reported is from trying to jam a String into a format specifier with %f, which requires a floating point type. Use float and there is no such exception.

Also, you can use Float.valueOf() to convert a String to a float in case your input data was originally a string (say, from a EditText or something). However, you should always try/catch valueOf() operations and handle the NumberFormatException case, since this exception is unchecked.