Open rkwright opened 9 years ago
danielweck
commented
9 years ago @nodehack (Tom Feldman), this looks like the first event is a "ghost" of the first one (see the different idref). @JCCR (Juan Corona) I seem to remember you mentioning having come across the same issue recently, but maybe I am mistaken?
nodehack
commented
9 years ago Looks like readium fires a pageDidChange event when setting view settings. The code shows that each time you open a page..if the the view type did not change then we set the view settings. I think this is incorrect. We should only be setting view settings if the desired view type changes.
In reader_view.js :
function openPage(pageRequest, dir) {
initViewForItem(pageRequest.spineItem, function(isViewChanged){
if(!isViewChanged) {
_currentView.setViewSettings(_viewerSettings);
}
_currentView.openPage(pageRequest, dir);
});
}I think you only want to setViewSettings if the desired view type changed..so it should read:
function openPage(pageRequest, dir) {
initViewForItem(pageRequest.spineItem, function(isViewChanged){
if(isViewChanged) {
_currentView.setViewSettings(_viewerSettings);
}
_currentView.openPage(pageRequest, dir);
});
}Thoughts?
Edit: Actually..upon further investigation I'm not sure why we need that if statement. initViewForItem already calls setViewSettings if the view type did change.
jdempcy
commented
9 years ago I had to code around this issue. Here is my workaround, which I do not advise as a permanent solution, but may be of assistance.
My goal was to register an onclick event on particular elements like audio and video tags. I need to register the event handler any time the DOM is overwritten and I assume it has to be triggered by a PAGINATION_CHANGED ("pageDidChange") event.
I was getting the problem where hooking into this event resulted in multiple registrations of my event handlers, so a single click would fire a function multiple times.
My solution was to set a flag on the HTML root node itself, knowing that I only need to re-register the event handlers when the HTML node was destroyed. You can see my code here:
// Register event handlers inside the iframe when it is loaded
ReadiumSDK.on(ReadiumSDK.Events.READER_INITIALIZED, function () {
ReadiumSDK.reader.on(ReadiumSDK.Events.PAGINATION_CHANGED, function () {
var $iframe = $('iframe');
var $htmlElement = $iframe.contents().find('html');
if ($htmlElement.attr('isEventHandlingRegistered')) {
// Do nothing
} else {
$htmlElement.attr('isEventHandlingRegistered', 'true');
$iframe.contents().find('audio, video')
.on('click', function (e) {
// Event handler code
});
}
}); // End PAGINATION_CHANGED
}); // End READER_INITIALIZEDIf I could rely on PAGINATION_CHANGED to only be triggered when the DOM is overwritten, I could remove the code which checks for a flag. But the solution outlined above seems to be working okay for me for now, so it isn't a blocking issue for me.
danielweck
commented
9 years ago FYI, I filed an issue here about the duplicated event: https://github.com/readium/readium-shared-js/issues/172
@jdempcy note that PAGINATION_CHANGED is triggered every time a reflowable document's page layout is potentially (but strictly-speaking: not necessarily) altered, for example due to changes in font size, line spacing, margins, viewport resizing, etc. The CONTENT_DOCUMENT_LOADED event is probably the one to use, if you need to inject behaviours only once per HTML DOM.
nodehack
commented
9 years ago @danielweck I added ReadiumSDK.reader.on(ReadiumSDK.Events.CONTENT_DOCUMENT_LOADED, this.onDocumentLoaded, this); to host_app_feedback.js and it does fire however I don't get any feedback to the native side via the request.
My onDocumentLoaded looks like:
this.onDocumentLoaded = function() {
window.location.href = "epubobjc:documentLoaded";
};Am I missing a step somewhere?
danielweck
commented
9 years ago @nodehack to wire the event into a native behaviour, add some handling code here: https://github.com/readium/SDKLauncher-iOS/blob/master/Classes/EPubViewController.m#L593
NSString *s = @"epubobjc:";
if ([url hasPrefix:s]) {
url = [url substringFromIndex:s.length];
if ([url isEqualToString:@"documentLoaded"]) {
From Tom Feldman: Hi all, I'm wondering if there is an api somewhere in the readium-shared-js or maybe even some standard javascript I can execute to know when javascript is done figuring out its paging routine. I was previously under the impression that a call to ReadiumSDK.reader.openPageNext() would result in a single callback request of pageDidChange when it was finished. If the spine item changes however, this callback is being requested more than once.
Here's a log of the requests:
You'll notice one call to the open next script and two pageDidChange events.