Treat collection of lines as a single object, so I can apply colors?

[Tz Ico]

I drew a custom triangle object with lines, but since they're not connected (DrawIO won't let me), I'm unable to do a 'fill color' on it.

Note to mods: I reposted this, due to previous post showing email address.

[draw.io Q&A]

In draw.io you can only apply a fill color to closed shapes. The individual line objects don’t form a “closed polygon,” so the editor doesn’t see them as something that can be filled.

Here are your options to fix it:

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Option 1 — Use the built-in triangle shape

1. In the General shape library (left toolbar), drag the triangle shape (second row, rightmost).

2. Resize it as needed.

3. You can then apply a fill color directly.

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Option 2 — Draw a custom closed shape

1. Select the Insert → Shape → Polygon tool (or use the freehand / polyline tool from the toolbar).

2. Click to place each vertex of the triangle.

3. Double-click to close the polygon.

4. With the polygon selected, apply a fill color.

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Option 3 — Convert your lines into a filled shape

1. Select all three lines.

2. Right-click → Arrange → Group (they’re still just grouped lines).

3. Unfortunately grouping alone won’t create a fill. You’d need to redraw as a polygon if you want to fill.