I need to display a huge image (at least 2000x2000) on Android with Titanium and let the user scroll around, just like they were using a scroll view on iOS. However, I know Android doesn't support the same kind of scroll view, so I opted to use an ImageView.
I'm unable to display this image properly or at least the way I'd like (without it being blurry when you zoom in) because of memory issues. Has anyone found a way to make large scrollable images work in Titanium on Android without potential memory crashes?
I tried WebView also, but it seemed to resize my image and when you zoomed it was blurry as well. I was hoping Android webview supported SVG, but it looks like they don't on a majority of devices.
This is by far the best answer I've found:
http://www.tenxperts.com/2011/07/13/working-with-large-images-in-android/
I tried it and it works well with Titanium web views.
Related
I have an angular 2 application in production environment that allows you to choose a profile picture. Recently, performing tests with safari mobile, specifically for IOS 13.3.1 version(older) and IOS 13.4.1(new) version. I noticed that the image is shown rotated depending of safari browser version used (I built a stackblitz for this that you can review):
IOS 13.3.1 version(older)
IOS 13.4.1(new)
When I take images from an iPhone's in portrait mode and upload the image to my app it is shown rotated only for IOS 13.3.1 version(older). However, I examined the EXIF meta-information images from each of my devices and found that both images have the same value in the orientation property:
IOS 13.3.1 version(older)
IOS 13.4.1(new)
My question is. Why does the image display change depending on the IOS version, knowing that in both cases the orientation EXIF is the same value (6)?
This is a subject that worries me since I had already solved this problem by rotating the image depending of EXIF orientation value for its correct display (e.g. exif.js have been created to handle this situation by detecting the exif orientation flag), but this problem now appears again with the new version of IOS. What would be an example of code that I can use to make it sustainable over time? Is there not a consensus among the browsers to manage the orientation of the images?
What is the explanation for this illogical behavior?
Thank you so much!
We also stumbled upon this when our mobile suddenly behaved differently and finally find the root cause of this.
Both WebKit (iOS) and Android (Chrome) have just recently changed the default behavior of the image-orientation CSS propterty. While it was none before, it is now from-image. This means: Before, they ignored the EXIF data of an image by default, while they are now using it to auto-correct the image. Which break our own auto-correction based on the exifreader library.
Here are some relevant links:
https://www.fxsitecompat.dev/en-CA/docs/2020/jpeg-images-are-now-rotated-by-default-according-to-exif-data/
https://bugs.webkit.org/show_bug.cgi?id=89052
Funny enough, also the Slack team seems to have run into this:
https://bugzilla.mozilla.org/show_bug.cgi?id=1634180
Fortunately, the author of the exifreader library (who just some weeks later ran into the same problems) also guided me to a way to detect the behavior. You can find his answer here:
https://github.com/mattiasw/ExifReader/issues/99#issuecomment-640217716
I also noticed that Modernizr has a test for this, so I am actually using a custom modernizr build now to detect the browser behavior.
The webkit browser is rotating the images before you upload them based on the EXIF data then it gets applied again by your app. We were able to confirm this on new (81) version of Chrome and Mobile Safari on 13.4. then the app is rotating them further and it gets twisted.
I am having performance and "jank" issues while scrolling on a Android React Native app. The JS FPS drops from ~60fps down to ~3-10fps while scrolling.
The content being scrolled DOES include images containing transparency and text layered over images. If I remove the images, performance increases significantly.
The above scenario sounds like a perfect case for renderToHardwareTextureAndroid. That said, enabling this property on a View containing the images/text seems to have no effect at all.
How can I confirm this feature is truly turned on and working as expected? Is it possible that something I am doing/not doing is forcing the hardware rendering to not take place?
So I made a project using Three.js and everything works how I want it to on desktop browsers, tested using chrome, and firefox. When I try to open the project on any mobile browser, safari, chrome, or IE, some objects are not rendered these objects have normal maps and textures which appear fine on desktop but are not rendered at all on mobile. In addition objects appear to be overly bright on mobile and sometimes flicker going from behind one another to in front of one another.
One user suggested adding this.image = image; to the three.js file at line 18420 but this did not solve the issue. Here is a link to the project here http://pixelpusher.ninja/Ocean%20World/OceanWorld.html. You can inspect the page to view the source code. Has anyone ran into problems like this on mobile before? Any help is appreciated. Thanks!
Very strange problem:
I've created a small HTML5 canvas game with box2dweb.js.
So far, all my work has been on desktop and today I've decided to move it to the iPhone (which usually consists of wrapping the app in a PhoneGap/Cordova application, change a few settings, and that's it.
The problem is, when I run the app on my desktop browsers (Chrome, Safari) as well as the iPhone and iPad simulators - everything works correctly - but when I actually deploy to my device (iPhone 4S) only some of the pictures show up. In fact, only the player sprite animation plays, and everything else (while still there physically) does not get drawn unless it doesn't have a specific animation (whether it's a sequence of images or just one image).
What seems even more strange, is that only the player entity is being drawn (with animation, too!) but all other entities that have animations are simply not drawn.
I've attached images to show the differences:
My question is - where do I even start debugging this? I tried running the index.html page without the cordova app on the iOS simulator so I could access the debug console, but there were no issues. How is this even possible? I was under the impression that if it worked as a web page, it should work as a PhoneGap app.
Alright, I've solved the problem. It was incredibly simple but hard to find. It's not even a PhoneGap problem:
The game has a level editor, and so it also has a saving/loading mechanism. While I specify all the images as './graphics/image.png', when a level gets deserialized it saves the loaded image's source, and not the original './graphics...' path. So the problem was that I was trying to load local files from my computer to my iPhone. I guess it was a path problem after all...
I have a problem with a Wordpress-run website: http://www.igorlipinski.com - Safari freezes and eventually crashes on iOS devices while using the zoom option, either double tap or pinch to zoom option. It looks and works very well on desktop browsers. I can't quite locate the problem... any thoughts? Thanks in advance!
UPDATE: I disabled javascript on my iPhone and the site worked beautifully, so at least I know where to look now! I would appreciate if anyone had a direct solution for this particular site, but I will work on it in the meantime.
I have faced similar kind of issue. Found issue with canvas drawing.
Basically there is one issue with canvas drawing. when we draw or erase something using canvas's methods like drawRect(), lineTo(), moveTo(), etc... it will create extra layer (like pixels on canvas) which causes memory leakage issue in safari browser for ipads/mobiles.
I am still looking for solution/alternative for memory leakage while using canvas.
Hope this will help you find any clue related to your project.