I'd like to push an alert to my iPhone users that are within a geographic range. I can get their location when my app is "alive," but not otherwise.
Would a good approach be: send the localized alert based on users that appeared "in-range" in the last hour? Otherwise, I'm not sure how to only alert relevant users.
Is there a smarter approach?
The lack of background processing really hurts applications like this. I think your solution is probably the best approach, given that rather severe limitation. However, you definitely should offer the ability to tone this down, as it could start to get really annoying.
Related
I know quite a few questions have been asked around this topic; however, am penning this as they don't seem to specifically answer my question, & some don't have any correct answer listed.
What I want to do in my iPhone App
Fetch some data when the App is not running (basically, it's a prefetch, so as to quicken it when the user uses the App the next time). What's the best way to do this?
Some Potential Solutions
Those that I could think of & some from Stackoverflow & such resources:
Possibility 1 : Fetch the data at a specific time of the day (maybe after midnight ?). Am not seeing 'clearly' how to do this if this this possible in the first place. Some suggest using a NSTimer -> but the timer is put off when the application is suspended, right?
Possibility 2 : Using local notification (?) But I see that Apple's documentation specifically mentioning that notification is to be used to convey something to the user & so this would defy Apple's doc then, right?
Possibility 3 : Through applicationDidEnterBackground -> beginBackgroundTaskWithExpirationHandler . This wouldn't run the fetch at a specific time of the day though. However, it might serve its purpose of 'pre'-fetching. Is this better than the other two?
Any thoughts please?
as you already know that none of the option you have presented are not going to work with ios and user can always close the background applications anyway so I would suggest that it'd be a good idea to fetch the data for next calendar day whenever the app is running.
As samfisher is saying none of your specs. fit with the Apple active background requirements. The only thing that I can suggest you is to use the beginBackgroundTaskWithExpirationHandler I understand that is a "post fetching" instead of prefetching but I guess is the only way.
The other way, but is a little bit trickier, is masquerade your prefetching with some sort of geolocation, in this way you could opt for an active background. This involve a lot of aspects such as:
Appstore rejection
Battery consumption
There are plenty of app on the appstore that use this trick, I can remember one that calculate data traffic.
My app is calling a web service to retrieve some data, and I want to make the experience as best as possible. I figured out that using NSURLConnection it's very hard to give good timely feedback.
Sometimes my iPhone tries to load the data for a minute or two and I see no way of figuring out what is taking so long, or why the download is so troublesome. Then after a few minutes I sometimes end up with an error code.
I'd like to display exactly what is happening. Messages like:
"Establishing internet connection"
"Trying to connect to server"
"Connected..."
"Downloading data..."
"Download complete!"
And when there is trouble like server not reachable or DNS could not be resolved, it would be nice to just try again a few times and not simply quit and throw error.
Are there replacements for NSURLConnection which handle these things more gracefully and give better in-time feedback about what is happening?
I've been a big fan of the AFNetworking library. Very easy to use and wraps all your networking calls in blocks that are very easy to work with.
It is also is kept very current, so you should be safe in getting all the updates it needs as your project progresses and ages.
I think you should be misusing NSURLConnection and NSURLConnectionDelegate, since you can do most of you needs with them.
But, what about MKNetworkKit? I've been using it and it really makes those kind of issues easier to deal with.
Something that can help you achieve what you want. Since ASIHTTPRequest is no longer being supported MKNetworkKit would be your best choice. To check for connectivity, you can always use Reachability.
I'm developing a navigation app which uses the UIBackgroundModes=location setting and receives CLLocationManager updates via didUpdateToLocation. That works fine.
The problem is that the intervals between location updates are very hard to predict and I need to make sure the app is called something like once every few seconds to do some other (tiny) amounts of work even if the location did not change significantly.
Can I do that? Am I allowed to do that? And how can I do that?
I found a blog post, but I'm not sure if this is really the way to proceed.
Permissible background operations are pretty limited in scope. You cannot, for example, just leave an NSTimer running to perform some arbitrary code while your application is in the background - so the simple answer to your question is no, you cannot. Definitely read the Apple documentation regarding what is and isn't allowed (most of what's allowed pertains to apps that "need" specific ongoing services, like the ability to play music, or respond to location changes (GPS type apps...). You may be able to construct a viable solution by responding to location or significant location change notifications...
Is there a way to simulate user activity on desktop on Windows? This is the situation: A friend of mine works from his home. His company recently decided to provide their employees with a communication tool which they have to keep running in the background. Apart from its main functionality it also has a very intimidating side effect: It tracks user activity. This means that the programm monitors keystrokes and mouse movements. If a user is idle for say 5 minutes or something, an icon next to his name indicates his idle status to all other users, much similar to instant messengers like skype for example. Now while this may be useful in IM programms, we both find it a bit disturbing in a work related context, for obvious reasons.
Doing some google search only gave me shareware links or cheating tools for MMORPGs. But maybe I searched for the wrong terms. My first guess would have been to have a small process running in the background which imitates keystrokes or mouse movement in regular intervals. But maybe there is another way to deal with this. (Oh, and complaining about lack of privacy to the employer is not an option ;) Also please note that I don't want to promote laziness or question an employer's rights over his employees.)
Any comments and help appreaciated. Thanks!
There is an easy way to make cursor move in C++.
its something like:
pos.X = 10;
pos.Y = 10;
I dont know if this is the best way, but it works.
If you dont want to program your own program, Im sure there are a lot of programs on the internet. You just need to google :) .
I've just started playing around with opengl es on the iphone the past couple of weeks and i'm looking at refactoring some of my code to use Vertex Buffer Objects(VBO). Before I do though I would like to make sure it'll be worth it. The problem is that afaik the only reason you create VBO's is to shift a chunk of data onto the graphics card so that it doesn't need to be retrieved from system ram when it's used. The iPhone however does not have any dedicated ram that I'm aware of so i'm struggling to see why I would benefit at all from using VBO's. I have seen talk around the internet with conflicting opinions and apple certainly want dev's to use it so there's probably still a reason to use them but just wanted to see if anyone on SO had an opinion to add.
I saw no performance improvement on an iPhone 3G. I moved a bunch of stuff to VBOs, but eventually backed it out as it made it more difficult for me to pursue other performance gains. It's not the quick 25% performance increase that I was hoping for.
I've read somewhere that it can make a difference on the newer hardware (3GS), but I don't have references to back that up.
It depends. (sorry).
Rob didn't see an improvement for his setup, but here is an interesting post that did see a large improvement.
The main reason to existence of VBO's is the presence of static data on 3D models. The first bottleneck you encounter is the slowness of copying data to video memory (by using the unavailable glBegin/glEnd block or glVertexPointer, glBufferData and friends).
Let's imagine the old "flying toaster" screensaver. All toasts are static (changing only the position) - why waste resources copying them every frame from CPU's memory to GPU's? Copy it once with buffers and draw it with a single command. And, depending on how you do animations, even the animated toasters can be described in a static fashion.
My first 2D game I started without VBOs. When I changed to VBOs, no difference (like Rob). But, when I refactored to use more static buffers, FPS gone from 20 to 40. Since my goal was to reach 30, I was satisfied. I had some ideas to refactor even more, leaving everything static, but I don't have time now (game is on review, next one to come).