I would like to format number using text type wiget like Label.
I know Grid has 'Configure Grid Columns' menu to configure number format, but above widget doesn't.
Should I make Thing's services to format number? or make a new Mashup to extend existing widgets?
Just use the value display widget instead of the label. It allows you to format your number any way you would like. If for some reason you do not want to use that widget, you will have to write a service to format your number for you.
Value Display has a renderer that you can configure.
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