Databases
StackOverflow2013
Postsdbo
POHow to manage a Bluetooth connection on Android through configuration changes?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to manage a Bluetooth connection on Android through configuration changes?
    primarykey
    data
    text
    <p><strong>Question:</strong><br> How can I manage (Connect, Read, Write, Disconnect) a bluetooth connection that persists through configuration changes?</p> <p>Prefer solutions that are compatible with device version 2.2 "Froyo" using <a href="http://actionbarsherlock.com" rel="nofollow noreferrer">ActionBarSherlock</a>.</p> <p><strong>Problems...</strong> </p> <ul> <li><p>Neither <code>BluetoothDevice</code> nor <code>BluetoothSocket</code> can be retained in <code>onSaveState</code>. </p></li> <li><p>In order to <a href="http://developer.android.com/training/articles/perf-anr.html" rel="nofollow noreferrer">keep my app responsive</a>, the 12 second blocking call <a href="http://developer.android.com/reference/android/bluetooth/BluetoothSocket.html#connect()" rel="nofollow noreferrer"><code>BluetoothSocket.connect()</code></a> must be made on a separate thread. Starting a <code>Runnable</code> is the recommended way to thread long tasks, but it's a nightmare trying to recover on a configuration change. The official docs point to three different solutions. </p> <ul> <li><p>Use <a href="http://developer.android.com/reference/android/app/Activity.html#getLastNonConfigurationInstance()" rel="nofollow noreferrer"><code>getLastNonConfigurationInstance()</code></a>, which is deprecated (seriously?!). </p></li> <li><p>Set <code>android:configChanges="keyboardHidden|orientation"</code> like the <a href="http://developer.android.com/tools/samples/index.html" rel="nofollow noreferrer">BluetoothChat Sample</a>. However, this does not account for all types of configuration changes.</p></li> <li><p>Cancel &amp; restart tasks like the <a href="http://code.google.com/p/shelves/" rel="nofollow noreferrer">Shelves Example</a>. In this case, this could potentially waste another 12 seconds.</p></li> </ul></li> </ul> <p><strong>Update 1</strong></p> <ul> <li><p>Further research led me to <a href="http://developer.android.com/reference/android/content/AsyncTaskLoader.html" rel="nofollow noreferrer">asyncTaskLoader</a>, but it seems like this can only update the UI on completion, and cannot provide updates. </p></li> <li><p>The BluetoothHDP sample uses a service. Services seem focused on inter-process communication and the need to persist beyond the activity life-cycle. I don't need either of these features. </p></li> </ul> <p><strong>Update 2</strong></p> <p><a href="https://stackoverflow.com/a/15731702/884677">As pointed out by Reuben</a>, <a href="http://developer.android.com/reference/android/app/Fragment.html#setRetainInstance(boolean)" rel="nofollow noreferrer"><code>Fragment.setRetainInstance(bool)</code></a> has replaced the deprecated <code>getLastNonConfigurationInstance()</code>. At this point, it seems like the best option is to make a persistent non-UI fragment using <code>setRetainInstance(true)</code>. </p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. USfiryice
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to manage a Bluetooth connection on Android through configuration changes?
      1. USfiryice
      1. VTBountyStart
    2. VO
      singulars
      1. POHow to manage a Bluetooth connection on Android through configuration changes?
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload