With the recent changes to lightbox image handling in #21145 and #20788
it is no longer necessary to have panning and zooming disabled by
default. This commit removes the enable/disable button and instead
replaces it with a "Reset Image" button, and enables panning and zooming
as the default state of the lightbox.
This commit attempts to prevent images with long filenames,
descriptions, or author names displayed in the lightbox from altering
the layout of the page.
It also adds a title prop to both the filename and author, allowing a
user to hover and see a tooltip of the full text in the case where the
text is truncated.
Fixes#21058.
This commit adds a method of marking an overlay as being meant to be
left open despite click events triggering that would normally close it.
This is to prevent the case where a user drags an image and "unclicks"
in an area where normally clicking would close the overlay.
This PR changes how the Pan & Zoom feature of images displayed in the
attachment lightbox are handled.
The existing method of using a canvas element is replaced by the Panzoom
library (timmywil/panzoom). This library is lightweight and has 0
transitive dependencies.
This fixes#20759 where the issue is that the viewport of a zoomed image
was not expanding to fill the available space on the page. Switching to
this new library also solves several other UX issues:
* Images are no longer blurred when in Pan & Zoom mode.
* The zoom behavior itself uses focal point zooming: zooming occurs
where the cursor is on the image instead of at the center of the
image, reducing the need for extra panning.
* CSS transitions are used for a more visually pleasing experience
when switching images, toggling zoom off, etc.
* The library has the potential to open other file types which
leaves that option open for us in the future.
The ‘t’ helper operates on text strings, not HTML. The ‘&’ works
fine, and is correctly escaped for output by Handlebars, like any text
string interpolated with ‘{{}}’.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Austin Riba
Austin Riba
Anders Kaseorg
Aman Agrawal
Ganesh Pawar