Improve resize on tooltip content change - use appropriate corner to pin tooltip, depending on gravity

[puzrin]

This issue is followup to #27.

Pinning point should be selected, depending on popover location. Then, if content grows, popover will change in proper direction without additional position recalulation.

1. Use-case for corners:

We load content in 2 stages:

• show dummy popup with "loading" progress
• substitute content

If popup grows on second step, then it overlap link (now). So, now we have to call recacculation, to move it up. But if you pin popup with bottom left corner, then it will automatically extend in proper direction (up and right).

IMHO, in practice, it would be very convenient to select "proper" pinned corner for each gravity option. Then it will change inproper direction without additional JS call.

2. Comments about side-placed (left-right-top-bottom) popups:

For side-placed tooltip there are no unique pinning solution. But it's limited to 2 possible choices, instead of 4. I don't have strong opinion, how to choose the best corner of 2.

IMHO, rigth now you can select any of 2, and if someone will have the real case in practice, then you could improve it. IMHO, if someone have top or bottom placed popup, he will fix width. Then content change will only affect height - no problem.

[stevenbenner]

This is on the to-do. Thanks for creating the issue!

[stevenbenner]

I've started working on this, and it has become apparent that using the bottom CSS attribute makes PowerTip vastly more vulnerable to body tag styling.

Because of the static position of the body tag, and the way it inherits the unique properties of the html tag, the bottom attribute for a child of body is relative to the window height. For example, setting bottom to 0px on a completely un-styled body tag will result in the element being placed at a position of however tall the view port is, not however tall the document is. (See: example)

This means that if anyone sets the position on the body tag to relative (or fixed, or absolute) it will totally break tooltip positioning.

Styling the body tag can already have some negative effects on tooltip placement, but none so devastating or difficult for a developer implementing PowerTip to diagnose.

I'm debating whether this is worth the risk.

[puzrin]

Got your point. Honestly, i'm not enougth competent, to guarantee good solution without risks. I think, it's better to postpone this issues to next milestone. May be, after 1-2 months we'll get better ideas, or someone with stronger experiance will decide to help.

[stevenbenner]

Update on this issue: The tooltip positioning was changed to use right positioning for w, nw, sw, ne-alt, and se-alt in commits f6b60c2 and 8be25f5.