GUI: radio button group without selection?

Image a couple of objects for which one property can have 3 possible values. To edit them I want to use a radio button group with 3 buttons. If you have one object selected, it's obvious which radio button to select. But which what to select if multiple objects with different values of this proper开发者_Python百科ty are selected? A radio button group without a selected radio button looks somewhat "naked".

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One possible solution would be to add a 4th button to the group that indicates that the property is not set. You could have that one be the default when you need an 'indeterminate' default setting. This would allow the radio button group to start out with a selected radio button.

That being said, I'm having a hard time visualizing your situation. Do you think you could add some more detail to your question? I think you are talking about the default state of the radio buttons, but I'm not totally sure.

Hope this helps.