Weird behavior UIComponents - ios

I'm newbie to iOS programming and I'm having a little trouble with UIComponents. I don't know why, but they aren't working properly. This images illustrates it:
It's weird because I've just drop the elements and in some cases, I change the font but not any big deal. As you can see, my labels and the "Register" button don't show up. The worst is that the log don't say anything, so I can't know what's going on. I cleaned the project, but it doesn't work.
Any clue what's wrong? It's not the number of lines or the value of alpha, I checked that
Thanks!

Related

How to get iOS app to work on all iPhones? (Constraints)

I am fairly new to developing for iOS. I have a fully functioning program written in Swift and the UI was created in the scene builder on Xcode. I created an app for my work to simplify closing out the registers and other financial aspects. The app is complete and works perfectly, but was designed on the iPhoneX. The problem is that only a few of the employees have an iPhoneX, but they all have some kind of iPhone. I have tried setting up constraints but it never works. Ive tried scaling restraints and position restraints but I can't get the layout to look right on any other phone, and when I add the constraints it affects the view on the iPhoneX as well and doesn't look good on any iPhone. I need help getting this to work on all iPhones. I would like it to look and act the exact same regardless of the size of the phone, basically just scaled down. There are a lot of things on the screen and I can't figure out how to do this. Please help!!!
I have been working on this for a long time and I really need help. Please let me know if I need to clarify anything. I have posted links to some pictures of my UI so you have an idea of whats going on.
Constraints I tried adding, although I have played around with some other options.
Here's what it looks like on the iPhoneX, this is how I want it to look.
What it looks like on iPhoneSE (with constraints).
One thing I noticed in your Xcode project that none of your features are in UIView. Without it, it will be quite challenging and somewhat always different results. In theory, if you use AutoLayout features correctly it should work without UIView, but they make life so much easier. This is something I learned the hard way at the beginning of my iOS development. First set up your UIViews without any content inside it, give them some background colour to differentiate, once they are working on all devices. You can pin your features to superviews with no difficulty.
Since you have a repetitive features, you could also consider using Stack Views. You don't have complicated features, so as long as AutoLayout is set up correctly you should have no problems seeing it ok on all devices

Random glitchy rendering of SVG on iOS/WKWebView

We are experiencing a bizarre intermittent (very occasional) render glitch when displaying SVG icons in our iOS app based on WKWebView.
When it does happen, it seems to be possibly tied to CSS in that if I change some random (even completely unrelated) CSS classes in Safari while debugging the page, the glitching can go away or come back randomly. There seems to be no rhyme nor reason to it though, and we don't have any way to reliably reproduce it yet.
Just wondering if anyone has any thoughts or may have encountered this before.
As you can see there are a couple kinds of glitches: the obvious garbled icons, but also there is only supposed to be one Metrics tab. That part is especially strange because the "Metrics" label is just text, not even part of the icon!
If I debug the element, it looks as it should in the debugger. The element has the right background image url and the label is as it should be (I can even hover over the label in the elements tree and it will highlight the label on the page, even though the text is completely wrong). It seems to get completely screwed up in the actual rendering somehow.
So we ended up finally solving this and it turned out not to have anything to do with SVG after all. The culprit was actually the CSS greyscale filter that was being applied, probably in combination with something else we were doing.
In short, removing the greyscale filter fixed the glitchy rendering.

Xamarin.Forms labels not working anymore, on iOS

I am making a Xamarin.Forms project, and I am in the end of my app, but something really strange have happened. My app starts up with no labels (!?), meaning they are invisible or not created at all. Everything else seems to be working, until I press a button that is supposed to change the label - when I do this, the app freezes. I get no exception in Visual Studio, though.
One problem is that my breakpoints in PLC code never hits, only those I place in the iOS code. However, the buttons not related to changing a label works, so I know the PLC code have been ran. If I let the app run for a little while, and then press the pause-button in VS debugging to see where in the code I am, it stops at
UIApplication.Main(args, null, "AppDelegate");
.. in Main.cs. I dont know if this is correct or not, when I run on Android, I get a Break Mode - No code is currently running.
I have been trying for hours to debug, reinstall, restart, clean and rebuild, but nothing seems to help. My code works perfectly in Android, and it worked in iOS 1 week ago. Anyone have any ideas what is going on, or what I can do to debug some more? Or must I make a new project and try start over?
Edit: I have also tried different starting pages, and all are the same: all views loads except those with text in them. I have a page with an Editor in it, and I can write in it, but no text is appearing inside of it. Only button have visible text. I do not use a custom font for my labels, I have not specified anything.
Waking up fresh in the morning, I found my issue in 15 minutes..
After altering my Google search to TextView iOS instead of Label Xamarin, I found much more answers. Thanks to this question and answer.
Basically, changing anything on the labels in the constructor of the page (even after InitializeComponent()), will mess up the view. I moved my code outside of the constructor (in the protected override void OnAppearing() method), and now it is working again.
The freeze part was not related - this was my custom menu that covered my screen with an invisible layout eating up all clicking events. A bit confusing, none of these issues are present in Android, but there you go.

UIButton image/backgroundimage scaling issues

I have tried everything, so I finally decided to post this question. I have a button (well, quite a few actually) that holds an image, which was working fine, until my employer decided they were too small. First thing I did was get some new pictures, that were bigger, so the resolution wouldn't be bad. Now when I tried to "oversize" my button, at some point the image just didn't want to follow anymore and stopped scaling. I went searching on the internet, and saw that everybody was telling ppl to put their image as background image instead. I did that, but then a new problem raised: resolution was awful. So basically I have two question.
1. Is it really not possible to make a buttons image scaletofill; do you really have to work around by using background image.
2. Is there any reason that somebody else can think of why my resolution would be bad, as the picture I use is actually bigger than the background (and the proportions are correct). I originally had smaller pictures, but I deleted them from images assets and loaded in the new ones. I can't imagine Xcode somehow retaining a snapshot of the old pictures, but this makes no sense to me.
Any clearance on the subject greatly appreciated!
Try to remove app from simulator or device and clean Xcode build cache (Build->Clean)

Flash text disappearing when using draw method

Working on an AIR iOS app and noticed a strange thing.
In my app I have a navigation panel that displays over the main content-holding Sprite. Having this panel display was causing the app to crash on iPad1 (guessing too much memory). So I added a function to basically draw the content-holder Sprite (via BitmapData draw function) into a Sprite above it, and turn the content-holder visibility off. Basically, taking a screenshot.
However, I'm seeing on 2 different iPads now that any dynamically added text in the content-holder isn't being drawn. Sometimes, the first time it does, but not after.
One thing noticed is that turning off the cacheAsBitmap property of the text fields fixes the problem. Unfortunately, that is not an option as the app is very text heavy and the performance is noticeably slower if the dynamically generated text isn't bitmapped.
Any ideas on what may be going on?
Thanks in advance for any help.
-Mark
Looks like cacheAsBitmap on the dynamic text fields was the problem. By turning that off temporarily, taking the screenshot and then turning back on when done with screenshot, I was able to work around the issue.
Not sure if it's an AIR/iOS issue or maybe a lack of memory?
FYI, in case somebody sees similar problem. Hope that helps.

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