There's a bunch of code, in the viewer, which for historical reasons use `switch` statements to add and remove CSS classes.
This code can be simplified, and unnecessary duplication avoided, by using `classList.toggle` instead.
The intention with preferences such as `sidebarViewOnLoad`/`scrollModeOnLoad`/`spreadModeOnLoad` were always that they should be able to *unconditionally* override their view history counterparts.
Due to the way that these preferences were initially implemented[1], trying to e.g. force the sidebar to remain hidden on load cannot be guaranteed[2]. The reason for this is the use of "enumeration values" containing zero, which in hindsight was an unfortunate choice on my part.
At this point it's also not as simple as just re-numbering the affected structures, since that would wreak havoc on existing (modified) preferences. The only reasonable solution that I was able to come up with was to change the *default* values of the preferences themselves, but not their actual values or the meaning thereof.
As part of the refactoring, the `disablePageMode` preference was combined with the *adjusted* `sidebarViewOnLoad` one, to hopefully reduce confusion by not tracking related state separately.
Additionally, the `showPreviousViewOnLoad` and `disableOpenActionDestination` preferences were combined into a *new* `viewOnLoad` enumeration preference, to further avoid tracking related state separately.
The new "private" method will return a boolean, indicating if the `sidebarviewchanged` event was dispatched, thus allowing some simplification of the `PDFSidebar.setInitialView` method.
This is similar to the format used by a number of other viewer components, and should simplify the `PDFSidebar` initialization slightly.
Furthermore, by using the `eventBus` it's no longer necessary for `PDFSidebar` to have a direct dependency on `PDFOutlineViewer`.
There's still room for improvement here, but this patch is at least a start (since it's not clear to me how best to handle the viewers).
If we want to (eventually) make it possible to resize the sidebar, then having its width indirectly affect the toolbar is going to wreck havoc on the media queries used to show/hide buttons in the main toolbar (since many of them depend on the toolbar state, and thus its width).
Updating all of the media queries dynamically with JavaScript seems like a non-starter, given that it'd cause *very* messy code. It thus seem to me that we'd need to fix the position of the sidebar, to have any hope of (in the short term) addressing issue 2072.
Hence, I'm suggesting that the we always layout the sidebar in a consistent vertical position, and only animate the `viewerContainer` rather than the entire `mainContainer`.
Fixes 4052.
Fixes bug 850591.
Since the very early days of the viewer, it's been possible to pass in a `scale` when opening a PDF file. However, most of the time it was/is actually being ignored, which limits its usefulness considerably.
In older versions of the viewer, if a document hash was present (i.e. `PDFViewerApplication.initialBookmark` being set) or if the document existed in the `ViewHistory`, the `scale` passed to `PDFViewerApplication.open` would thus always be ignored.
In addition to the above, in the current viewer there's even more cases where the `scale` parameter will be ignored: if a (valid) browser history entry exists on document load, or if the `defaultZoomValue` preference is set to a non-default value.
Hence the result is that in most situation, a `scale` passed to `PDFViewerApplication.open` will be completely ignored.
A much better, not to mention supported, way of setting the initial scale is by using the `defaultZoomLevel` preference. In comparision, this also has the advantage of being used in situations where the `scale` would be ignored.
All in all this leads to the current situation where we have code which is essentially dead, since no part of the viewer (by default) relies on it.
To clean up this code, and to avoid having to pass (basically) unused parameters around, I'd thus like to remove the ability to pass a `scale` to `PDFViewerApplication.open`.
As discussed in PR 8673, we cannot solve the general issue (since that would require parsing every single page). However, we can mitigate the effect somewhat, by waiting for the FileAttachment annotations of the initially rendered page.
Note that these files were among the first to be converted to ES6 classes, so it probably makes sense to do another pass to bring them inline with the most recent ES6 conversions.
Note that as discussed on IRC, this makes the viewer slightly slower to load *only* in `gulp server` mode, however the difference seem slight enough that I think it will be fine.
A longstanding issue with the viewer is that you cannot tell if a PDF document includes an outline and/or attachments without actually opening the sidebar.
This patch contains a suggested solution for that, by displaying an hide-on-interaction notification on the `sidebarToggle` button (and the relevant sidebar view buttons). Note that this was inspired by e.g. the update notification that is displayed on the menu button in Firefox.
For an initial implementation, I've tried to do this in such a way that the notification isn't too distracting. Without being an UX expert, I don't think that we'd want something too in-your-face, in order to keep the viewer toolbars reasonable clean. (We probably do *not* want e.g. an entire notification bar in these situations, since that would take up unnecessary screen space and require actions from the user to close.)
However it's certainly possible that the current notification might simply be *too* inconspicuous to be truly helpful to users, but we could probably iterate on that if the feature itself is deemed useful.
We cannot piggy-back on the `updateviewarea` event in order to update the stored sidebar state, since there're a number of cases where opening/switching the sidebar view won't fire a `updateviewarea` event.
Note that `updateviewarea` only fires when the position changes in the *viewer*, which means that it won't fire if e.g. the viewer is narrow, such that the sidebar overlays the document transparently; or when switching views, without the document position also changing.
This patch also moves the handling of `forceOpen` parameter in `PDFSidebar_switchView`, to prevent triggering back-to-back rendering and dispatching of events.
Functionality wise, `ensureThumbnailVisible` is essentially just a shorthand for `scrollThumbnailIntoView`. (And note that `PDFViewer` doesn't implement a `ensurePageVisible` method.)
The only remaining usage of `PDFThumbnailViewer_ensureThumbnailVisible` is inside `PDFPresentationMode`, which introduces an otherwise unnecessary `PDFThumbnailViewer` dependency there.
We're already relying on the `presentationmodechanged` event, in various files, to track the state of Presentation Mode. Thus we can simply listen for that event in `PDFSidebar` too, and update the thumbnails if necessary.
The sidebar code has, except for minor fixes/additions (such as attachments), been largely untouch for years.
To avoid having a bunch of sidebar code sprinkled throughout viewer.js, this patch moves the sidebar code into a separate file (pdf_sidebar.js), similar to how most other functionality has been moved in the last few years.
Besides simply moving code around, this patch also has the added benefit that we now keep track of the sidebar state (not just opened/closed).
This now makes it possible to handle both `Preferences` *and* `ViewHistory` settings for the sidebar state in a cleaner way, preventing strange and confusing interactions between the two.
