Android Application Development For Dummies, 2nd Edition

Creating Your Preferences Screen

Creating preferences using the PreferenceActivity and a preference XML file is a fairly straightforward process. The first thing you do is create the preference XML file, which defines the layout of the preferences and the string resource values that show up onscreen. These string resources are presented as TextViews onscreen to help the user determine what the preference does.

Your PreferenceScreen should give users the chance to set the default time for a reminder (in minutes) and a default title for a new task. As the application stands now, the default title is empty and the default reminder time is set to the current time. These preferences allow the user to save a couple of steps while building new tasks. For example, if the user normally builds tasks with a reminder time of 60 minutes from the current time, the user can now specify it in the preferences. This new value becomes the value of the reminder time when the user creates a new task.

Building the preferences file

To build your first preferences screen, create a res/xml folder in your project. Inside the res/xml folder, create an XML file and name it task_preferences.xml. Add the code in Listing 15-1 to the file.

Listing 15-1: The task_preferences.xml File

<?xml version=”1.0” encoding=”utf-8”?>

<PreferenceScreen →2

xmlns:android=”http://schemas.android.com/apk/res/android”>

<PreferenceCategory →4

android:key=”@string/pref_category_task_defaults_key” →5

android:title=”@string/pref_category_task_defaults_title”> ...