After Updating to Flutter 3.7.0 i get this error message when i build my App:
[app_en.arb:scanCode_fieldNotMatched] ICU Syntax Error: Expected "identifier" but found "0". field to match is "{0}"
It seems as if something had changed in how the variables are written in the .arb localization files.
If what you are trying is to use the characters {, }, ' (or any other syntax character for that matter) in your strings, then you will have to escape them. To do that enable the use-escaping flag by adding the following to l10n.yaml
use-escaping: true
Now use pairs of single quotes to escape syntax characters, like "{". To escape single quotes you just have to write it as a double-single quote as follows:
{
"some_text": "Using the '{' character '{isn''t}' trivial?"
}
More details on this in the flutter docu.
Follow details in this issue.
I found out that the reason for this error is that in Flutter 3.7
Internationalization support has been completely revamped! [they]’ve completely rewritten the gen-l10n tool...
as stated in a release post.
Previously i was declaring strings in my .arb file as follows
"scanCode_fieldNotMatched": "field to match is \"{0}\"",
where afterwards i was replacing {0} by some other value.
Well, it seems that now the gen-l10n tool takes what is between brackets as special parameters, and the name "0" is not accepted so i had to change my string to
"scanCode_fieldNotMatched": "field to match is \"{value0}\"",
and AppLocalizations can be now called as:
AppLocalizations.of(context)!.scanCode_fieldNotMatched("something here to replace value0!")
Further details on this can be found here: Placeholders, plurals, and selects in Flutter.