The big question here is: how do I update my activity from a service? In the next example we are going to use two classes you may not be aware of: ResultReceiver and IntentService. ResultReceiver is the one that will allow us to update our thread from a service; IntentService is a subclass of Service which spawns a thread to do background work from there you should know that a Service runs actually in the same thread of your app; when you extends Service , you must manually spawn new threads to run CPU blocking operations.
Groundy is a library that basically helps you run pieces of code in a background service, and it is based on the ResultReceiver concept shown above. This library is deprecated at the moment. This is how the whole code would look like:. A GroundyTask implementation used by Groundy to download the file and show the progress:. It couldn't be easier I think.
Just grab the latest jar from Github and you are ready to go. Keep in mind that Groundy 's main purpose is to make calls to external REST apis in a background service and post results to the UI with easily. If you are doing something like that in your app, it could be really useful. GingerBread brought a new feature, DownloadManager , which allows you to download files easily and delegate the hard work of handling threads, streams, etc. Method's name explains it all. Once you are sure DownloadManager is available, you can do something like this:.
First and second methods are just the tip of the iceberg. There are lots of things you have to keep in mind if you want your app to be robust. Here is a brief list:. Unless you need detailed control of the download process, then consider using DownloadManager 3 because it already handles most of the items listed above. But also consider that your needs may change. For example, DownloadManager does no response caching.
It will blindly download the same big file multiple times. There's no easy way to fix it after the fact. So the initial effort of learning the basic, standard tools can be a good investment. This class was deprecated in API level ProgressDialog is a modal dialog, which prevents the user from interacting with the app.
Instead of using this class, you should use a progress indicator like ProgressBar, which can be embedded in your app's UI. Alternatively, you can use a notification to inform the user of the task's progress. For more details Link. Don't forget to add permissions to your manifest file if you're gonna be downloading stuff from the internet!
Yes the code above will work. But if you are updating your progressbar in onProgressUpdate of Asynctask and you press back button or finish your activity AsyncTask looses its track with your UI. And when you go back to your activity, even if download is running in background you will see no update on progressbar. So on OnResume try to run a thread like runOnUIThread with a timer task that updates ur progressbar with values updating from the AsyncTask running background.
I'd recommend you to use my Project Netroid , It's based on Volley. I have added some features to it such as multi-events callback, file download management. Learn more. Asked 4 years, 6 months ago. Active 4 months ago. Viewed 14k times. The problem File is downloading silently, no notification in the notification area. Request Uri. Build Information Here is my Gradle Build infformation. Improve this question. Christlin Panneer. Christlin Panneer Christlin Panneer 1, 1 1 gold badge 15 15 silver badges 29 29 bronze badges.
Add a comment. Active Oldest Votes. July 31, at pm. Sandeep says:. May 27, at am. Kashinath S. Chari says:. March 15, at pm. A notification in its most basic and compact form also known as collapsed form displays an icon, a title, and a small amount of content text. In this section, you'll learn how to create a notification that the user can click on to launch an activity in your app.
Figure 1. A notification with a title and text. For more details about each part of a notification, read about the notification anatomy. To get started, you need to set the notification's content and channel using a NotificationCompat.
Builder object. The following example shows how to create a notification with the following:. Notice that the NotificationCompat. Builder constructor requires that you provide a channel ID.
This is required for compatibility with Android 8. By default, the notification's text content is truncated to fit one line. If you want your notification to be longer, you can enable an expandable notification by adding a style template with setStyle.
For example, the following code creates a larger text area:. For more information about other large notification styles, including how to add an image and media playback controls, see Create a Notification with Expandable Detail. Before you can deliver the notification on Android 8. Because you must create the notification channel before posting any notifications on Android 8.
It's safe to call this repeatedly because creating an existing notification channel performs no operation. Notice that the NotificationChannel constructor requires an importance , using one of the constants from the NotificationManager class. This parameter determines how to interrupt the user for any notification that belongs to this channel—though you must also set the priority with setPriority to support Android 7.
In some cases the system might change the importance level based other factors, and the user can always redefine what the importance level is for a given channel.
For more information about what the different levels mean, read about notification importance levels. Every notification should respond to a tap, usually to open an activity in your app that corresponds to the notification.
To do so, you must specify a content intent defined with a PendingIntent object and pass it to setContentIntent. The following snippet shows how to create a basic intent to open an activity when the user taps the notification:. Notice this code calls setAutoCancel , which automatically removes the notification when the user taps it. The setFlags method shown above helps preserve the user's expected navigation experience after they open your app via the notification.
But whether you want to use that depends on what type of activity you're starting, which may be one of the following:.
For more about the different ways to configure your notification's intent, read Start an Activity from a Notification. To make the notification appear, call NotificationManagerCompat. For example:. A notification can offer up to three action buttons that allow the user to respond quickly, such as snooze a reminder or even reply to a text message.
But these action buttons should not duplicate the action performed when the user taps the notification. Figure 2. A notification with one action button. To add an action button, pass a PendingIntent to the addAction method. This is just like setting up the notification's default tap action, except instead of launching an activity, you can do a variety of other things such as start a BroadcastReceiver that performs a job in the background so the action does not interrupt the app that's already open.
For more information about building a BroadcastReceiver to run background work, see the Broadcasts guide. If you're instead trying to build a notification with media playback buttons such as to pause and skip tracks , see how to create a notification with media controls. The direct reply action, introduced in Android 7. For example, you can use a direct reply action to let users reply to text messages or update task lists from within the notification.
Figure 3. Tapping the "Reply" button opens the text input. The direct reply action appears as an additional button in the notification that opens a text input. When the user finishes typing, the system attaches the text response to the intent you had specified for the notification action and sends the intent to your app. Caution: If you re-use a PendingIntent , a user may reply to a different conversation than the one they thought they did.
You must either provide a request code that is different for each conversation or provide an intent that doesn't return true when you call equals on the reply intent of any other conversation.
The conversation ID is frequently passed as part of the intent's extras bundle, but is ignored when you call equals. The system prompts the user to input a response when they trigger the notification action, as shown in figure 3. To receive user input from the notification's reply UI, call RemoteInput. This is necessary to hide direct reply UI and confirm to the user that their reply was received and processed correctly. When working with this new notification, use the context that's passed to the receiver's onReceive method.
You should also append the reply to the bottom of the notification by calling setRemoteInputHistory. For more advice for notifications from a messaging apps, see best practices for messaging apps.
I tried going to the Files app as some sites mentioned , which states "Notifications: on", but when I select it, the Categories part is empty, so there is nothing to disable. So, which app is actually emitting the Download Manager notifications, and how can I disable them? List them by tapping on the three dots line in the upper right corner and choosing show system apps.
Download Manager is a system app and you would find it apps list. To disable the notifications from that app, tap on that app in the list, then Notifications, and choose an option there that fits your needs.
Just wanted to add an answer for this that I found on Reddit, in case it disappears. Scroll to Download Manager. Clear cache, clear storage, force stop, disable, enable. Of course, your download history will be cleared if you do this, but it's up to you to decide if that's worth it :.
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