ComboBox: iOS focusing on Text Input after tapping dropdown button

[jh2he]

On iOS, tapping on the drop-down button of the ComboBox will open the popout then immediately close it.
Possibly this is caused by the auto focus on the Text Input, highlighting the selection, which causes the flyout to lose focus.
This happens not all of the time, but very frequently.

Is there a property I can set to not have it auto focus on the Text Input when clicking on the Button/Icon?

Environment Information

• Package version(s): Latest 6.125 https://fabricweb.z5.web.core.windows.net/oufr/6.125.0/#/examples/ComboBox
• Browser and OS versions: iOS only, Chrome and Safari.
  Tested on iPhone X. iOS 12.

Actual behavior:

Tapping the dropdown button opens and immediately closes the popout.

Expected behavior:

Tapping the drop down button should show the flyout without issues.

Priorities and help requested:

Are you willing to submit a PR to fix? Yes, but I will need to take while to familiarize with ComboBox.

Requested priority: Normal

Products/sites affected: Microsoft Dynamics 365

[mikewheaton]

I'm not able to repro this in Safari on an iPhone 7 Plus or iPad Pro, both running iOS 12.1.2.

You mentioned that this doesn't always happen; do you see any patterns for when it does or doesn't happen?

[jh2he]

If the control is at the top of the page, it seems to have no trouble. If it's near the bottom or maybe lower-middle, the keyboard might be blocking/closing the popout instantly.

[mikewheaton]

It's not disappearing for me, but I can get into a weird state where the input I'm typing in is covered by the options.

Seems like the menu should be anchored to the top of the input and its height should be constrained to fit in the viewport so results can be seen.

[dzearing]

@jspurlin fyi

[dzearing]

I repro'd. Weird. It seems like the click on the chevron isn't getting prevented, and it flows up, which maybe selects the text.

[dzearing]

Shoot this is reproable in chrome. We should not select the text when clicking on the chevron.