Cannot arrow through signature help after clicking on widget

[mjbvz]

Issue Type: Bug

Repo

1. For a js file:

import * as fs from 'fs';

fs.readFile(

1. Trigger signature help on readFile
2. Click on signature help widget
3. Now try using arrow up and down to go through signatures

Bug
After clicking on the widget, the arrow keys stop going through the signatures

VS Code version: Code 1.30.1 (dea8705, 2018-12-18T18:05:00.654Z)
OS version: Darwin x64 18.2.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz (8 x 2200)
GPU Status	2d_canvas: enabled checker_imaging: disabled_off flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: enabled rasterization: enabled video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled
Load (avg)	5, 4, 4
Memory (System)	16.00GB (0.09GB free)
Process Argv
Screen Reader	no
VM	22%

[mjbvz]

This is caused by us using kbExpr: EditorContextKeys.editorTextFocus on these commands: https://github.com/Microsoft/vscode/blob/8a58c3e7a67a82f9ef2c0f318d67c411eaed6959/src/vs/editor/contrib/parameterHints/parameterHints.ts#L111

@alexandrudima or @jrieken Is there there's better context key we should use here? Or can we omit the context entirely since the precondition already restricts when the parameter hints are active?

[jrieken]

You would need your own context key expressing that the widget is visible

[alexdima]

Yes, I suggest introducing parameterHintsVisible (which would be true/false depending on the widget state) and using the keybinding condition editorFocus && parameterHintsVisible.

editorFocus means focus is somewhere in the dom node of an editor.
editorTextFocus means focus is in the editor's input textarea.

[mjbvz]

editorFocus seems to be the way to go but clicking on the signature help currently take focus out of the editor entirely. Will keep looking into this

[alexdima]

clicking on the signature help currently take focus out of the editor entirely

@mjbvz That is not what I am observing. editorFocus is true even if the focus is moved to the parameter hints widget because the dom node parameter-hints-widget is a child of the dom node monaco-editor. That is the reason there are two distinct context keys, editorFocus and editorTextFocus.

[mjbvz]

The context is correct when the signature help widget first appears but it gets lost as soon as I interact with the arrow buttons. editorFocus becomes false but the activeEditor context remains "workbench.editors.files.textFileEditor"

Looks like document.activeElement moves to the body element:

[alexdima]

@mjbvz You would need to make the widget focusable (tabIndex > 0) and then add keybinding rules for arrow up and arrow down. I think you are observing how browsers work. i.e. what you describe has nothing in particular to do with VS Code.

[mjbvz]

Thanks @alexandrudima! I tried a few different approaches but ended up calling editor.focus on button clicks. We still want to allow the user to type in the editor after clicking on the parameter hint buttons. Focusing the parameter hints widget prevents this