1page.title=Displaying Progress in a Notification 2page.tags=notifications 3helpoutsWidget=true 4 5trainingnavtop=true 6 7@jd:body 8 9<div id="tb-wrapper"> 10<div id="tb"> 11 12<!-- table of contents --> 13<h2>This lesson teaches you to</h2> 14<ol> 15 <li><a href="#FixedProgress">Display a Fixed-duration progress Indicator</a></li> 16 <li><a href="#ActivityIndicator">Display a Continuing Activity Indicator</a></li> 17</ol> 18 19<!-- other docs (NOT javadocs) --> 20<h2>You should also read</h2> 21 22<ul> 23 <li> 24 <a href="{@docRoot}guide/topics/ui/notifiers/notifications.html">Notifications</a> API Guide 25 </li> 26 <li> 27 <a href="{@docRoot}guide/components/intents-filters.html"> 28 Intents and Intent Filters 29 </a> 30 </li> 31 <li> 32 <a href="{@docRoot}design/patterns/notifications.html">Notifications</a> Design Guide 33 </li> 34</ul> 35 36 37</div> 38</div> 39 40 41 42<p> 43 Notifications can include an animated progress indicator that shows users the status 44 of an ongoing operation. If you can estimate how long the operation takes and how much of it 45 is complete at any time, use the "determinate" form of the indicator 46 (a progress bar). If you can't estimate the length of the operation, use the 47 "indeterminate" form of the indicator (an activity indicator). 48</p> 49<p> 50 Progress indicators are displayed with the platform's implementation of the 51 {@link android.widget.ProgressBar} class. 52</p> 53<p> 54 To use a progress indicator, call 55 {@link android.support.v4.app.NotificationCompat.Builder#setProgress setProgress()}. The 56 determinate and indeterminate forms are described in the following sections. 57</p> 58<!-- ------------------------------------------------------------------------------------------ --> 59<h2 id="FixedProgress">Display a Fixed-duration Progress Indicator</h2> 60<p> 61 To display a determinate progress bar, add the bar to your notification by calling 62 {@link android.support.v4.app.NotificationCompat.Builder#setProgress 63 setProgress(max, progress, false)} and then issue the notification. 64 The third argument is a boolean that indicates whether the 65 progress bar is indeterminate (<strong>true</strong>) or determinate (<strong>false</strong>). 66 As your operation proceeds, 67 increment <code>progress</code>, and update the notification. At the end of the operation, 68 <code>progress</code> should equal <code>max</code>. A common way to call 69 {@link android.support.v4.app.NotificationCompat.Builder#setProgress setProgress()} 70 is to set <code>max</code> to 100 and then increment <code>progress</code> as a 71 "percent complete" value for the operation. 72</p> 73<p> 74 You can either leave the progress bar showing when the operation is done, or remove it. In 75 either case, remember to update the notification text to show that the operation is complete. 76 To remove the progress bar, call 77 {@link android.support.v4.app.NotificationCompat.Builder#setProgress 78 setProgress(0, 0, false)}. For example: 79</p> 80<pre> 81int id = 1; 82... 83mNotifyManager = 84 (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE); 85mBuilder = new NotificationCompat.Builder(this); 86mBuilder.setContentTitle("Picture Download") 87 .setContentText("Download in progress") 88 .setSmallIcon(R.drawable.ic_notification); 89// Start a lengthy operation in a background thread 90new Thread( 91 new Runnable() { 92 @Override 93 public void run() { 94 int incr; 95 // Do the "lengthy" operation 20 times 96 for (incr = 0; incr <= 100; incr+=5) { 97 // Sets the progress indicator to a max value, the 98 // current completion percentage, and "determinate" 99 // state 100 mBuilder.setProgress(100, incr, false); 101 // Displays the progress bar for the first time. 102 mNotifyManager.notify(id, mBuilder.build()); 103 // Sleeps the thread, simulating an operation 104 // that takes time 105 try { 106 // Sleep for 5 seconds 107 Thread.sleep(5*1000); 108 } catch (InterruptedException e) { 109 Log.d(TAG, "sleep failure"); 110 } 111 } 112 // When the loop is finished, updates the notification 113 mBuilder.setContentText("Download complete") 114 // Removes the progress bar 115 .setProgress(0,0,false); 116 mNotifyManager.notify(id, mBuilder.build()); 117 } 118 } 119// Starts the thread by calling the run() method in its Runnable 120).start(); 121</pre> 122<p> 123 The resulting notifications are shown in figure 1. On the left side is a snapshot of the 124 notification during the operation; on the right side is a snapshot of it after the operation 125 has finished. 126</p> 127<img 128 id="figure1" 129 src="{@docRoot}images/ui/notifications/progress_bar_summary.png" 130 height="84" 131 alt="" /> 132<p class="img-caption"> 133<strong>Figure 1.</strong> The progress bar during and after the operation.</p> 134<!-- ------------------------------------------------------------------------------------------ --> 135<h2 id="ActivityIndicator">Display a Continuing Activity Indicator</h2> 136<p> 137 To display a continuing (indeterminate) activity indicator, add it to your notification with 138 {@link android.support.v4.app.NotificationCompat.Builder#setProgress setProgress(0, 0, true)} 139 and issue the notification. The first two arguments are ignored, and the third argument 140 declares that the indicator is indeterminate. The result is an indicator 141 that has the same style as a progress bar, except that its animation is ongoing. 142</p> 143<p> 144 Issue the notification at the beginning of the operation. The animation will run until you 145 modify your notification. When the operation is done, call 146 {@link android.support.v4.app.NotificationCompat.Builder#setProgress 147 setProgress(0, 0, false)} and then update the notification to remove the activity indicator. 148 Always do this; otherwise, the animation will run even when the operation is complete. Also 149 remember to change the notification text to indicate that the operation is complete. 150</p> 151<p> 152 To see how continuing activity indicators work, refer to the preceding snippet. Locate the following lines: 153</p> 154<pre> 155// Sets the progress indicator to a max value, the current completion 156// percentage, and "determinate" state 157mBuilder.setProgress(100, incr, false); 158// Issues the notification 159mNotifyManager.notify(id, mBuilder.build()); 160</pre> 161<p> 162 Replace the lines you've found with the following lines. Notice that the third parameter 163 in the {@link android.support.v4.app.NotificationCompat.Builder#setProgress setProgress()} 164 call is set to {@code true} to indicate that the progress bar is 165 indeterminate: 166</p> 167<pre> 168 // Sets an activity indicator for an operation of indeterminate length 169mBuilder.setProgress(0, 0, true); 170// Issues the notification 171mNotifyManager.notify(id, mBuilder.build()); 172</pre> 173<p> 174 The resulting indicator is shown in figure 2: 175</p> 176<img 177 id="figure2" 178 src="{@docRoot}images/ui/notifications/activity_indicator.png" 179 height="99" 180 alt="" /> 181<p class="img-caption"><strong>Figure 2.</strong> An ongoing activity indicator.</p> 182
