Too easy to accidentally close the drawer when scrolling on mobile (regression of #73)

[ronnyroeller]

Description

Issue #73 occurs again:

When the drawer contains a tall list and the user wants to scroll that list, it is way too easy to accidentally close the drawer because the finger will drag diagonally and a very little horizontal movement will close the drawer.

In the Inbox app, you have to drag left past 50% width to make the drawer close, similar for opening the drawer. Also, in the Inbox app, when you start scrolling the drawer up or down, the drawer is prevented from closing. The drawer will either close or scroll, but not do both.

I think paper-drawer-panel could temporarily disable dragging when a upward or downward finger movement has been detected.

Expected outcome

Horizontal scrolling should be locked when scrolling vertically through the drawer.

Actual outcome

One closes the drawer accidentally when scrolling vertically through a drawer because horizontal scrolling isn't locked any longer.

Live Demo

Example: https://output.jsbin.com/hopikoxeqa

Browsers Affected

• Safari on iOS 9.3 (13E233)
• Chrome on iOS 9.3 (13E233)

[frankiefu]

This is because setScrollDirection in Polymer is not working: Polymer/polymer#3667

[5amfung]

Polymer team had a chance to look into this issue?