Suggestion: Make Fixed widgets state their preferred size about brick HOT 1 CLOSED

Thanks for writing this up.

The reason this isn't already the way things are implemented is because it's not as straightforward as one might like. The reason is because the space taken up by a widget (even if it declares Fixed) is not static but depends on the box in which it is rendered. Fixed doesn't exactly mean "the same size every time" or "a fixed size", but rather "not greedy."

For example, a text string that needs to be wrapped has a definite size and won't greedily consume the whole window the way a list might, but it can't say with certainty how big it will be in the future once rendered, because that depends on how much space you give it, and that depends on the layout conditions that exist at rendering time, and those conditions depend on other rendering operations that cannot be statically determined. If you give it enough width, it might be one row high, but it might wrap to two or more rows if not given enough columns. So if it reported a size, anything that used that size to make decisions would get the wrong answer under certain layout conditions.

It allows UI elements to degenerate in an orderly fashion when not given enough space. Currently the highest level boxRenderer just crops the resulting table. It would be more sensible if it instead rendered the sub-widgets with less space than requested.

On this note, I suspect this is going to result in behaviors that are very difficult to predict. For example, would you prefer a dialog box to get cropped, or would you prefer only its buttons to disappear? Which one would be easier to detect visually when you resize the terminal? Cropping at the top level (as a consequence of greed policies, mind you) may seem messy, but I think that makes it more obvious that you just made your terminal too small.

from brick.