Unanswered: How do I make a combo _always_ show in a grid even if the property is empty
I haven't found documentation that helps me with this. I have a SimpleComboBox which is used as an editor for a property; I want the combo to show even if the property contains no value. Right now users find it confusing, because they don't know that they can click on the field to choose a value, since there's nothing to prompt them to click.
What have you tried? Do you need this just for the trigger icon, or do you want some blank text to tell the user [not set, click here to set a value]? If the former, have you looked at the samples (like http://www.sencha.com/examples/#ExamplePlace:cellgrid specifically the Light column, with a custom cell set)? If the latter, a custom cell that renders a special 'empty' string when it is given a blank value might be for you.
If you don't get a reply, please don't assume that everyone is ignoring you. In a Q/A forum, it is important to not just ask questions, but to ask good questions.
GXT is extremely flexible, so there are not a lot of reasonable things that are 'not possible'. This is part of what makes it difficult to use - we've tried very hard to allow for many many ways to configure and extend the widgets. In my book, drawing the [V] icon on every single row looks bad - it looks like a row on its own, not just a marker that makes it easier to know you can click something. Which means changing the question you are asking to "How can I make it clearer that the user can click to edit?". I would answer that with "Write help text above the Grid", or "On hover, have the cell highlighted slightly so the user recognizes that they can interact with it".