Android widget's fixed update frequency

Question

In order to have Widget, we need to maintain an XML file (AppWidgetProviderInfo) which describes the properties of the widget, e.g. size or fixed update frequency like this:

<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
    android:minWidth="160dp" 
    android:minHeight="72dp"
    android:initialLayout="@layout/widget_layout"
    android:updatePeriodMillis="1800000"
    android:configure="android.project.WidgetConfigure" >

</appwidget-provider>

and Maintain the App Widget configuration in the AndroidManifest.xml.

<meta-data
        android:name="android.appwidget.provider"
        android:resource="@xml/widget_info" />
 </receiver>

I know that we can not edit the updatePeriodMillis. programmatically and we need to use AlarmManager. (Android Widget set android:updatePeriodMillis programmatically)

But how can I read that value from the xml file programmatically. Is there any way ?

Addenda:

try {
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(getApplicationContext());
        AppWidgetProviderInfo info = appWidgetManager.getAppWidgetInfo(R.xml.widget_info);
        System.out.println("Time: " + info.updatePeriodMillis);
    } catch(Exception err) {
        err.printStackTrace();
    }

If I use this code in an Activity, it returns NullPointerException in catch.

avimak · Accepted Answer · 2013-07-05T13:31:02.780

1

updatePeriodMillis is a value which the system uses in order to send you a proper broadcast once that period's time has come. Why will you want to read it and trigger an AlarmManager intent for the exact same time?

After your edit: You are passing the wrong "id"; you should pass the actual widget id, not its XML metadata id. As I wrote in my last comment, try this: AppWidgetManager.getInstance(), then use AppWidgetManager.getAppWidgetIds() to retrieve your widget(s) id, then continue as discussed (AppWidgetManager.getAppWidgetInfo() ...)

edited Jul 05 '13 at 13:31

answered Jul 05 '13 at 12:35

avimak

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I don't want to do that. That sentence was just an information with the link, but I wanted to see how to read it. – Ali Jul 05 '13 at 12:36
Oh, I see. There is more then one way to do it, but did you consider simply read the file and parse it? Take a look here: http://stackoverflow.com/questions/4329308/open-xml-file-from-res-xml-in-android – avimak Jul 05 '13 at 12:39
It means that I have to parse the xml file and there is no simpler code. is it what you meant? – Ali Jul 05 '13 at 12:44
No, you mustn't read the file itself, you can call `AppWidgetManager.getAppWidgetInfo()`, then read `AppWidgetProviderInfo.updatePeriodMillis` – avimak Jul 05 '13 at 12:52
It was a good point. But then it seems that I can get it with this code as you said (and I add as Addenda) within the Widget Class (extends AppWidgetProvider). `not in other activities.` but +1 for your guides till now. – Ali Jul 05 '13 at 13:16
Have you tried the following code from your Activity? `AppWidgetManager.getInstance()`, then use `AppWidgetManager.getAppWidgetIds()` to retrieve your widget(s) id, then continue as above (`AppWidgetManager.getAppWidgetInfo()` ...) – avimak Jul 05 '13 at 13:21
Yes, the codes are added at the end of my question, but returns NullPointerException. – Ali Jul 05 '13 at 13:24

Android widget's fixed update frequency

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