Stroke on only one side of a square?

cripes, this is a simple thing to do in ms word.

steal it from them, adobe, they steal everything else...

I've also been trying this method: drawing a line and then setting is as an anchored object. The downside is that you may need to manually resize the line if the text box changes. The upside is it's simple to use and the line can easily be manipulated like any other stroke in InDesign:

I found this:

Setting a dots stroke to the yellow squares and directional feather to eliminate the stroke of each side.

The window below is for the bottom left yellow shape:

so it took Adobe 5 years, but now you can...

Use a table with a single cell.

It's not possible - but it should be.

Yet it is possible in Adobe Muse!!!

Are you listening Adobe? We want this feature in InDesign.

This was bugging me too, and I tried this solution:

1. Select your object
2. Create a new Object Style (Window >  Styles > Object Styles)
3. Under options for the object style, select "Inner Shadow"
4. Turn "Preview" on because you're going to need to finagle with the settings
5. Key settings to adjust:
   1. Blending mode should be normal,
   2. Opacity should be 100%
   3. Choke must be 100%
   4. Size should be 0
   5. Play with the position values. Usually X and Y offset will be 0
   6. Distance will determine the "border" width.
   7. Angle determines the side the border will be on
6. Save the style

What I'm essentailly doing here is choking the inner shadow on the box to a solid line, then adjusting the position of that shadow to just stick in on one side. This creates the illustion of a solid line. You won't have to cut up the object, you don't need multiple objects grouped together, the line will always move and adjust with the object, and you don't need to add text to mimic a line. The downsides are that it takes a few minutes to adjust the thickness and position just right, so be sure to turn on your preview; and this works best on 4-sided objects.

You could draw a 0.5pt line, then <cut> it and <paste> it in using the text insertion cursor at the top of your text frame. Select the line, and nudge it up by about 9pt.

Alternatively, you could use a Right-indent tab <shift+tab> at the top of your text frame, and give that line a paragraph rule above. If you offset the rule by about 3mm, it lines up okay.

Either way, it's a kludge. It would be nice if frames supported different strokes on each side. When going to HTML/CSS feels 'easy and liberating', something's screwy :/

For non-quadrilateral polygons, Adobe could just do what they do everywhere else, and grey-out the options where a feature isn't supported. Given the number of times I use triangles and stars, this would inconvenience me approximately never.

That would be a very useful feature. You can do it in tables but not in boxes.   I'm going to submit a feature request for it -- you can do the same and maybe we'll get it eventually!

The only way to have a stroke on one side of a squrae that I know of, other than drawing a separate rule (presuming you mean you want a stroke on a vertical edge -- for horizontal you could use a paragraph rule), is to use a one-cell table.