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.
Related
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.
I am using Instruments (for the first time) as I am trying to debug a lag time arising on a real device but not on the simulator. I have collected some data but I am stuck now since I don't know very well how to interpret them.
Briefly, when I try to present a presentationController in my app I am faced with a lag time (about 5 sec) before the UIView appears on screen. I want to display a UITextView with attributed text. I registered the process with Instruments and here is what I can see (4 figures):
All I have understood so far is that there is maybe a problem with Core Graphics and Font. Could anyone help me to figure out what is going wrong and how I could get rid of this problem? I can give more code if needed.
EDIT:
This is what I obtained when applying the advice given, but I can still not figure out how I can refer those lines to my code.
You want to click these check boxes at the bottom of the time profiler:
from:
http://imgur.com/j0anIdf
to:
http://imgur.com/8PFU5VX
Now you should see your calls rather than all calls
I am having a problem with iOS scrolling on an iPad. Every other platform tested works just fine. I love iOS, but hate it too. I was able to get the entire iframe contents scrolling within the parent, but there are two DIVs that are fixed that shouldn’t scroll within the iframe.
Before I spend a lot of time trying to work this out, I am just looking to leverage everyone’s experience for whether it, in fact, CAN be done. If it IS possible, then I will proceed to trying to work out a simple model and report it back for others. If experience shows that it can NOT be done, then you will all have saved me a lot of headache, not to mention time.
Here’s a drawing of what works on all other platforms but NOT iOS:
Simple question: Is it possible?
The simple answer is, in fact, YES.
I'm experiencing a weird issue with my Swift 2.0 app.
I have a (editable) UITextView defined in my storyboard.
If I leave the text property empty in the storyboard everything is working as expected. But when I enter the text Kaasje (in the storyboard and recompiling), the app freezes when loading the nib (navigating through segue) and the CPU jumps to 100% (the app remains stuck).
The app will never reach viewDidLoad at this point.
It makes no difference when changing between fonts or fontsizes, behavior remains.
Pausing in Xcode does not leave me with anything useful, the main thread is busy without specifying any function. Nothing is logged to output nor any logs are created.
I'm running iOS9 on a iPad Air, the app has a built target of iOS8 and runs landscape-only.
Has anyone ever experienced anything like this before, and might have an explanation for this behaviour?
As far as my assumptions: Something goes wrong when calculating the text-size which results in a infinite loop while either calculating the size or adjusting the frame.
P.S. It happens with other texts too, but "Kaasje" always fails. It seems to fail when the the text is only 1 line. Longer texts tend to succeed aswel as leaving it empty.
As suggested in the comments there seems to be a bug in Xcode 7 in combination with iOS9.
I ended up recreating the entire view, the problem did not occur again.
Does anyone know if the iPad has any limitations on the canvas tag?
Currently I'm working on a creative that uses a flipbook and audio tag combination to simulate inline video content. The animations are drawn to the canvas element and synced with the audio content being played. There are 4 short video clips that get played when someone clicks on the four buttons below.
http://cs.sandbox.millennialmedia.com/~tkirchner/rich/K/kungfupanda2_test/
The problem I'm having though is in iPad. After playing a few animations, mobile safari just suddenly crashes. It never happens when I play it on my iPhone but it happens every time on the iPad. Its not one particular animation either because if I click a different combination of buttons, the previous clip that it crashed on plays fine, and then it decides to crash on another clip.
I think the problem might have to do with the amount of memory Safari gives individual page views. I found a blog post that explains that problem pretty well.
http://roblaplaca.com/blog/2010/05/05/ipad-safari-image-limit-workaround/
According to that post, once mobile Safari reaches a particular threshold of memory, images begin to return blank. This is consistant with my finds so far. The iPad that I'm testing this all on is running iOS 3.2.1 (and before anyone tells me that I should just explain to my boss that nobody uses 3.X anymore, I tried... they still want me to investigate this). I borrowed a co-workers iPad running iOS 4.2.1 and that device didn't crash, but some of the images weren't being drawn to the canvas.
I'm pretty sure its a problem with the canvas tag too, because I tried experimenting with running the animation without drawing anything to the canvas element, and the page never crashed.
Thats why I think maybe its a limitation with Safari's support of the canvas tag. Of course, I'm open to anybody else's suggestions.
Feels kinda weird answering my own question again, buuuut I figured if anyone did a search on this kind of question, an answer would be helpful.
I believe my original hypothesis was correct. The total amount of images that the aniamtions were using was around 600+. I think the older iPad loaded as many as it could and then when it ran out of cache and the canvas tag was trying to draw images that weren't really there anymore, it crashed.
Eventually we ended up serving the ad to devices with iOS 4.2 and higher, since the problem didn't seem to occur on those newer devices. Plus, we compressed the image sizes further, so that helped reduce the amount of images we were storing into memory.
If anybody knows approximately what the cache threshold in iOS 4.2 or higher browsers are, I'd appreciate it if you commented. Just want to get an idea of how many KB of image data I can safely load.