How to Multitask in iOS 7 | ohwander.tk

 

barra multitasking ios 7

The powerful new multitasking and networking APIs in iOS 7 open up a whole range of possibilities for both new and existing apps. Consider the use cases in your app which can benefit from out-of-process network transfers and fresh data, and make the most of these fantastic new APIs. Aug 09,  · That’s multitasking in iOS 7. It knows what you want to do before you do. Another little new feature with iOS 7 multitasking, at least in the current beta 5 of iOS 7, is the ability to quit multiple apps at once via the multitasking bar. You can use a three . Get to know iOS 7: Multitasking. Of course, you may want more specific control over which apps are accessing information in the background. Visit Settings > General > Background App Refresh to find a list of all the apps updating in the background, as well as a slider to deactivate them. If you’re concerned about battery life.


Multitasking in iOS 7 · ohwander.tk


Prior to iOS 7, developers were pretty limited in what they could do when their apps left the foreground. Aside from VOIP and location-based features, the only way to execute code in the background was to use background tasks, restricted to running for a few minutes. The first, Background Fetch, allows you to fetch new content from the network at regular intervals.

The second, Remote Notifications, is a new feature leveraging Push Notifications to notify an app when an event has occurred. Background Fetch and Remote Notifications are simple application delegate hooks with 30 seconds of wall-clock time to perform work before your app is suspended. Social networking, news, or weather apps can now display the latest content without the user having to open the app.

Background Fetch is a kind of smart polling mechanism which works best for apps that have frequent content updates, like social networking, news, or weather apps. For example, if the user always uses an app at 1 p. The value of UIApplicationBackgroundFetchIntervalMinimum asks the system to manage when your app is woken, as often as possible, but you should specify your own time interval if this is unnecessary.

For example, barra multitasking ios 7, a weather app might only update conditions hourly. This is where you can perform work when you are woken by the system. Remember, you only have 30 seconds to determine whether new content is available, to process the new content, and to update your UI.

This should be enough time to fetch data from the network and to fetch a few thumbnails for your UI, but not much more. When your network requests are complete and your UI has been updated, you should call the completion handler.

The completion handler serves two purposes. First, the system measures the power used by your process and records whether new data was available based on the UIBackgroundFetchResult argument you passed.

Second, when you call the completion handler, a snapshot of your UI is taken and the app switcher is updated. The user will see the new content when he or she is switching apps. This completion handler snapshotting behavior is common to all of the completion handlers in the new multitasking APIs. If your app is currently suspended, the system will wake it before calling application: performFetchWithCompletionHandler:, barra multitasking ios 7.

If your app is not running, the system will launch it, calling the usual delegate methods, including application: didFinishLaunchingWithOptions:. You can think of it as the app running exactly the same way as if the user had launched it from Springboard, except the UI is invisible, rendered offscreen. There are two ways you can simulate a background fetch.

Alternatively, you can use a scheme to change how Xcode runs your app. From here, edit or add a new scheme and check the Launch due to a background fetch event checkbox as shown below. Remote notifications allow you to notify your app when important events occur.

Remote notifications are great for sporadic but immediately important content, where the delay between background fetches might not be acceptable. Remote Notifications can also be much more efficient than Background Fetch, as your application only launches when necessary.

A Remote Notification is really just a normal Push Notification barra multitasking ios 7 the content-available flag set. You might send a push with an alert message informing the user that something has happened, while you update the UI in the background. If your push notifications are throttled, they might be barra multitasking ios 7 until the next time the device sends a keep-alive packet or receives another notification.

To send a remote notification, set the content-available flag in a push notification payload. The content-available flag is the same key used to notify Newsstand apps, so most push scripts and libraries already support remote notifications.

This could save you a few networking requests and increase the responsiveness of your app. Here the -n flag specifies that the content-available key should be included, and -d allows us to add our own data keys to the payload. Again, the barra multitasking ios 7 is launched into the background and given 30 seconds to fetch new content and update its UI, before calling the completion handler. There are barra multitasking ios 7 types of session tasks — data, download, and upload — each of which add syntactic sugar to NSURLSessionTaskbarra multitasking ios 7, so you should use the appropriate one for barra multitasking ios 7 use case.

Tasks added to a background session are run in an external process and continue even if your app is suspended, crashes, or is killed, barra multitasking ios 7. One option is the discretionary flag, which allows the system to schedule tasks for optimal performance. What this means is that your transfers will only go over Wifi when the device has sufficient power, barra multitasking ios 7. The discretionary flag only has an effect if the session configuration object has been constructed by calling the backgroundSessionConfiguration: method and if the background transfer is initiated while your app is in the foreground.

If the transfer is initiated from the background the transfer will always run in discretionary mode. We create a download task using the NSURLSession class method and configure its request, and provide a description for use later. You must remember to call [task resume] to actually start the task, barra multitasking ios 7, as all session tasks begin in the suspended state. If your app is still running in the foreground when the background session task completes, the above code will barra multitasking ios 7 sufficient.

In these cases, you must implement two application delegates methods so the system can wake your application. Unlike previous delegate callbacks, the application delegate is called twice, as your session and task delegates may receive several messages. In the former method, you store a background completionHandlerand in the latter you call it to update your UI:. Additionally, barra multitasking ios 7, if the app is not running at all when the background transfer finishes, iOS will launch it into the background, and the preceding application and session delegate methods are called after application:didFinishLaunchingWithOptions:.

You can use this to specify how long you want to allow for a transfer to complete before giving up entirely. In addition to download barra multitasking ios 7, NSURLSession fully supports upload tasks, so you might upload a video to your server in barra multitasking ios 7 background and assure your user that he or she no longer needs to leave the app running, as might have been done in iOS 6.

Efficient use of system resources keeps both iOS and the user happy. Finally, there are a couple of limitations in using background sessions. Launching your app into the background is relatively expensive, so HTTP redirects are always taken.

The system optimizes transfers based on available resources and you cannot force your transfer to progress in the background at all times.

Also note that NSURLSessionDataTasks are not supported in background sessions at all, and you should only use these tasks for short-lived, small requests, not for downloads or uploads. The powerful new multitasking and barra multitasking ios 7 APIs in iOS 7 open up a whole range of possibilities for both new and existing apps.

Consider the use cases in your app which can benefit from out-of-process network transfers and fresh data, and make the most of these fantastic new APIs. In general, implement background transfers as if your application is running in the foreground, making appropriate UI updates, and most of the work is already done for you.

In this article. Background Fetch Background Fetch is a kind of smart polling mechanism which works best for apps that have frequent content updates, like social networking, news, or weather apps. Remote Notifications Remote notifications allow you to notify your app when important events occur. Sending Remote Notifications To send a remote notification, set the content-available flag in a push notification payload. See backgroundURLSession above.

This should not happen. Summary The powerful new multitasking and networking APIs in iOS 7 open up a whole range of possibilities for both new and existing apps. Be efficient, and call completion handlers as early as possible.

 

Get to know iOS 7: Multitasking | Macworld

 

barra multitasking ios 7

 

Sep 23,  · 2 iOS Multitasking Orientation iOS 7 will match the orientation of your phone in the app manager. Note that once you enter the app manager, the orientation will remain locked until you exit again. 3 iOS Multitasking Homescreen To quickly jump to Author: Max Eddy. The powerful new multitasking and networking APIs in iOS 7 open up a whole range of possibilities for both new and existing apps. Consider the use cases in your app which can benefit from out-of-process network transfers and fresh data, and make the most of these fantastic new APIs. Apr 19,  · Use Multitasking gestures on your iPad to quickly see the app switcher, switch to another app, or return to the Home screen: See the app switcher: In iOS 12, swipe up with one finger from the bottom edge of the screen and hold in the middle of the screen until the app switcher appears.