View loading as blank/white screen in Mac desktop application Xamarin.Mac - xcode

I have a Mac desktop application developed using Xamarin.Mac and XCode. The application is loading views that should have a considerable amount of content as blank/white screens for a select few end users. While I've not been able to reproduce the issue locally and it doesn't appear to be impacting many people, it does happen consistently for a handful of users(6 out of over 4,000 at the moment). The app works just fine for the vast majority and uses a main window controller that sets the content view as needed by calling the applicable ViewController. When the views in question are loaded for the given users, it renders as a blank white area.
I did notice however that at least some of the objects in the views are actually there, just not visible. For instance, one view has buttons that are still "there" as you can click on them if you know where they are supposed to be positioned(and they also fire correctly) but they are not actually visible as the area is all white with no visible content. It's as if everything is loading properly but the UI just isn't cooperating in displaying objects that are actually there. The closest thing I could find was this Diagnosing run loop issue (partially frozen UI) in Cocoa application
However I'm not sure it's the same problem and there was no resolution for that either. Has anyone else ever encountered something like this?
Ok, got some new info. After doing a remote session with a user we had no luck with the hardware and the console didn't provide much insight, however we did stumble across a workaround that fixes the issue and may give some clues as to the real problem.
When the application is initially installed, we prompt the user to ask if they want it moved to the default Applications directory. They do not have to move it as it will work the same from pretty much anywhere but we do this for convenience. For the users having this problem, we noticed that they all had the app installed in the Applications folder. By sheer luck, one user accidentally chose to not move the app after reinstalling it per our support team. When the app was installed in his default Downloads directory, the problem vanished and the app worked as expected.
After testing various other directory locations(Downloads, Documents, etc.) we found that the issue only seemed to exist if the app was installed in the Applications directory. Furthermore, if the app was installed in the Applications directory, we could simply move it or copy/paste it to another directory outside Applications and when launching it from that new location the issue was resolved.
Seems like there is something specific to the default Applications directory that is causing this to happen(as odd as that sounds). Keep in mind that even when the app is installed in the Applications directory, this issue only happens to 7 people out of over 4,000.
Any ideas as to what might be special about that directory that could explain what we're seeing?

Related

Notifications not working on Windows 10 - Electron JS

I was learning Electron and made a basic electron app and packaged it for windows. The app was not showing notifications so I followed the instructions here
On Windows 10, a shortcut to your app with an Application User Model ID must be installed to the Start Menu. This can be overkill during development, so adding node_modules\electron\dist\electron.exe to your Start Menu also does the trick. Navigate to the file in Explorer, right-click and 'Pin to Start Menu'. You will then need to add the line app.setAppUserModelId(process.execPath) to your main process to see notifications.
I did as suggested here and the notifications started working. They were still working after packaging the app. So I wanted to check whether after a user uses an installer to install this app, the notifications would still work.
I don't have any experience with packaging software, and I used InstallForge to make an installer. Turns out, after installing the app using the installer, the app still works but notifications don't, even after pinning the exe to start.
I tried copying the build folder (direct build, not the installer one) to another location and trying the same thing and it still works. This also works if I copy the installation folder to another location. But it does not work from inside Program Files(x86)\myapp\appname\build\myapp.exe so I am assuming this must be something about permissions, but I do not understand exactly what is happening. I have't checked the app yet on Linux so I don't know if I would face similar problems there as well.
Any pointers would be great, Thank you.

Common dialogue control seems to keep my programs running after I close them

I currently run a 64bit Windows 10 development box. I have old VB6 source that I have to unfortunately keep updated for the time being. For some reason all the sudden I noticed that one of the applications I have just built seemed to stay running in the background after the GUI was closed.
I started debugging the issue more and more until I found out that the only time it would seem to persistently stay open in the background after the GUI was closed was if I clicked the button on my form that would call the Common Dialog control to show the file open GUI. I only have to show the file open window and then hit cancel for this to happen.
This ONLY seems to happen on ONE of my dev machines (not the other). Every time I use that CD file open box I have to open task manager up and end the task. I also tried to make sure all forms were closed when my main form starts to Unload. Nothing seems to work or shed any clue on what the issue is. I have also double checked that the following files are now all the same coping them from the known working dev machine to my broken one and re-registering them.
COMDLG32.OCX
comdlg32.oca
comdlg32.dll
COMDLG32.DEP
Both machines are running the same exact OS Win10 Pro 64bit.
That does sound strange, getting different results on the two machines. Pragmatically, you can work around the problem (without actually understanding it) by making sure that you execute an End statement. (You can put it in the QueryUnload event to make sure it's hit if the user clicks the "X".)

Missing required icon file - exactly 120x120, 76X76, etc... Attempted solutions but no success

So I've recently redesigned the UI of one of my apps, which I'm looking to update. As a finishing touch, I've also redone the app icon for iPhone and iPad. Like the first time, I used a mac app Asset Catalog Creator and Prepo or websites like MakeAppIcon.com and AppIcon.build, or some other closely related online app to create Homescreen and other icons. Typically, these are successful right off the bat. Unfortunately, after a number of failed attempts, as soon as I try to "validate", I receive several errors regarding missing icons.
I've used the mentioned apps and websites several times in the hopes of some success... no avail. I've tried adding the individual files directly from Sketch, with no luck. I even added each item in my assets in the info.plist and I'm still receiving the same errors. I am unsure how to proceed and would greatly appreciate some assistance.
After a week of frustration, it would seem all I had to do was select my project and under the "genera" tab, look for the "App Icons and Launch Images" section, and select the "App Icons Source" to "Use Asset Catalog." From there, I was able to simply drag and drop the images created from my icon generator and drop them into one of the icon image spots. From here, all you have to worry about is adding any extra images the generator may not have automatically created.

How to implement "Open With" contextual menu in OS X

Apps in OS X that can open files to launch their respective applications often let the user choose the app that'll open the file. An example is the Finder.
I am still unclear about what's the best solution to implement this. The challenges are performance and showing the app's icon.
First, to get the list of apps, I found only LSCopyApplicationURLsForURL().
The major difficulty for me now is to get the app icons. All I have is the URLs (paths) to the apps. The only way I know of to get the icons would be to create a CFBundle object and then read the app's plist to get the icon data. But that appears to invole lots of disk access, and I could imagine it'll be quite inefficient if the app is located on a remote file server.
I believe that there's also a cached database about the apps, which includes icons and display names (without extension), and such. But where is the API for that?
Note: The app is Carbon based, but I can make use of Cocoa (NS...) functions if necessary. Also, Support for 10.5, even 10.4, would be appreciated.
Alright. I solved it eventually.
I now use the Carbon function GetIconRefFromFileInfo(), which still works in Lion, though it's marked deprecated/obsolete.
I had also tried to use QLThumbnailImageCreate(), but that didn't get me any results, oddly. No idea what I did wrong.
For Cocoa apps, [[NSWorkspace sharedWorkspace] iconForFile:path] can be used (thanks to C. Grunenberg of DevonTechnologies for this tip, where it's used with EasyFind).

Mobile Safari application cache bugs?

I'm using Mobile Safari's cache manifest file to store a multi-page data entry application that is run on an iPod Touch (version 3.1.3) in offline mode. The application writes to the client-side database by way of the persistence.js ORM. This all works fine.
However, I run into the occasional, extremely hard to reproduce problem whereby Safari just seems to forget that the pages are cached. When this happens, the "Cannot Open Page" alert appears, which is the same one that comes up when you attempt to visit a non-cached website with the wi-fi turned off. The only way that I've found to fix this is to reconnect to a wireless signal and visit the site while online, which seems to set the cache straight. This is easy to do when you're in the office, but not so easy to do out in the field.
I'm not trying to reference anything outside of the cached resources, and I've verified that the application is cached by running through the entire site while disconnected, sometimes successfully for days on end. I feel like there's a bug in the OS that messes with the validity of the cache. I'm not necessarily looking for a solution to the problem (but that would be nice), but rather just some confirmation that others have encountered this problem.
Using a cache manifest and lot of troubleshooting, I am able to reliably cache an entire application; Do note that this is a single page app with only a few separate file resources.
As a further enhancement, I have been trying to modify the DOM based on
window.applicationCache status
to inform the user about updates, ie:
tap here to apply update
If that were possible, I could swap the cache
window.applicationCache.swapCache();
Which would allow me to swap in the updated cache and then restart the page to provide a streamlined update mechanism.
Potentially even more streamlined than apps from the apple store.
I suspect that the applicationCache API was hamstrung by Apple to hinder web apps for this very reason. Having said that, I believe the level of support for "html5" APIs on mobile devices is among the most robust in apple's safari.
Following are a few problems I have noticed so far, in no particular order. Please note that this is not a comprehensive list of bugs.
I never get an 'updateready' event; this alert line never runs:
window.applicationCache.addEventListener('updateready', function(e) {
alert('updateready event status=' + window.applicationCache.status );
}, false);
I can not manually check for updates. The following code gives me an exception
try{
window.applicationCache.update();
}catch (err){
alert('exception:\n' + err);
}
It seems that as soon as I start to interact with the cache state at all, the caching stops working. The bugs are fiendishly elusive; pinning down & isolating any one issue can take a lot of time, especially since all this code runs flawlessly on other browsers (chrome).
Now here's a good one:
I suspect that if you pin an app to your home screen, iCloud "backs up" resources and restores them after you run the app for the first time from the home screen. To avoid this issue, you may sometimes have to rename files. I have proven that apple makes discrete backups of obsolete components by
removing them entirely from my app server
deleting the pinned web apps from home screen
clearing all the caches
opening the app url in safari
verify that its the newest version
pin to home
verify that the pinned app the newest version
close it
run again - and its back to the old one, no longer on your server.
Finally, if you run the pinned app while the phone is in airplane mode, iCloud will not be able to restore the obsolete files. This proves that it's coming from over the air.

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