Fix issue "$apply in progress....."

[andy-maca]

Sometime cause error: $apply already in progress.

[wesleycho]

Explain your situation in detail as to why this is necessary. On its face, this looks like a potentially dangerous fix that will prevent proper garbage collection of the element.

[andy-maca]

This issue only happen in case some other operation trigger the $rootScope.$apply at the same time when move out a popover directive, I can only reproduce this issue by fast clicking some buttons with 'ng-click'.

[wesleycho]

In this case, I think a safer fix would be to do

$timeout(function() {
  hide();
});

There is a garbage collection danger in your approach that would not properly GC the tooltip due to the possibility that the hide function never gets run.

[andy-maca]

Right, this would be better.