I have Listpreferences in my app. They don't appear to be setting to their defaults right after installation - they appear to be null. I'm trying to figure out why my default preferences are not being set right after installation. In my main code I have:
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
InUnits = sp.getString("List1", "defValue");
InAngs = sp.getString("List2", "defValue");
OutUnits = sp.getString("List3", "defValue");
OutAngs = sp.getString("List4", "defValue");
Right after the above code executes, each variable contains "defValue" instead of the actual values I have assigned in my ListPreference below.
My preference xml file is called, "settings.xml". Here's what one of the ListPreferences there looks like:
<ListPreference
android:key="List1"
android:title="Input: Alph"
android:summary="Choose Alph or Ralph"
android:entries="#array/inputAlph"
android:entryValues="#array/input_Alph_codes"
android:dialogTitle="Input Alph"
android:defaultValue="ININ"/>
Here's what some of my strings.xml file looks like:
<string-array name="inputUnits">
<item>Alph</item>
<item>Ralph</item>
</string-array>
<string-array name="input_Alph_codes">
<item>ININ</item>
<item>INMM</item>
</string-array>
When I go to menu, and then settings, I can see my defaults checked (radiobuttoned). Then when I go back from the settings menu to my main screen - all is well - for life! ...then each var above is assigned the proper default value.
This only happens when I first install my app on the phone. After I go to the settings screen once and then right out of it, the app is fine and accepts any setting changes.
By the way, as you can see, "List1" is the android:key within a file called settings.xml in my res/xml folder.
They don't appear to be setting to
their defaults right after
installation - they appear to be null.
That's what's supposed to happen.
I'm trying to figure out why my
default preferences are not being set
right after installation.
They're not supposed to be. The preference XML you have listed there is only used for populating a PreferenceActivity, nothing more. Until the user opens the PreferenceActivity, the preferences will be null, and the defaults you supply to the SharedPreferences getters will be returned.
UPDATE
You can use setDefaultValues() on PreferenceManager to assign the defaults from your preference XML to a SharedPreferences. However, be careful of the timing -- this will do disk I/O, and therefore ideally is performed on a background thread.
Set the default values to SharedPreferences from your preference XML.
PreferenceManager.setDefaultValues(Context context, int resourceId, boolean readAgain)
PreferenceManager.setDefaultValues
You can specify a default value like this
SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(this);
pref.getString("thePrefKey", "theDefaultValue");
The android:defaultValue="..." in the "layout" settings.xml is only a visual help for user
Related
I'm trying to gain access to a (custom) list preference and change its selected value (i.e. if index 3 is selected, change the selection to index 1). However, findPreference() can only be used inside a PreferenceActivity. I need to access the preference and change its selection inside a regular Activity. Is there a way this can be done? I don't see anything in SharedPreferences that I can use to change the selection, only a list preferences value.
This is how you do it,
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreference(this);
prefs.getString(PREF_KEY, "default");
I have a settings.xml file that contains Preferences for my app. All the values by default are set to "true" and its used by PreferenceActivity in my app.
In my main activity I read the values through
SharedPreferences sp=PreferenceManager.getDefaultSharedPreferences(appContext);
Boolean key = sp.getBoolean("M", false);
it gets me whatever I need at any run except the first time. Only when I open my app for the first time and doesn't open my settings menu I get "false". I mean I have to open menu and only after that the app run correctly.
Any suggestions?
Because yor are getting the default value for first time.
that is false -->
Boolean key = sp.getBoolean("M", false);
use this
Boolean key = sp.getBoolean("M", true);
Use sp.getBoolean("M", true); instead. Default values in preferences file is what it will be when preferences activity is first started. SharedPreferences know nothing about your settings.xml.
Alternatively you can have a separate defaults.xml file (or any other name) containing all the default values for all preferences. Then you use these values in both settings.xml (#bool/default_M_value) and your application (sp.getBoolean("M", getResources().getBoolean(R.bool.default_M_value))).
I personally would stick to first approach though.
Hello fellow programmers, I have a little problem with Preferences activity.
http://developer.android.com/reference/android/preference/PreferenceActivity.html
I've got just one preference category and a listPreference:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceCategory android:title="#string/basic_settings" >
<ListPreference
android:defaultValue="70"
android:entries="#array/listArray"
android:entryValues="#array/listValues"
android:key="updates_interval"
android:persistent="true"
android:summary="#string/SOME_SUMMARY"
android:title="#string/SOME_TITLE" />
</PreferenceCategory>
I need to have the selected value (the default one or the user defined one) written in the summary of the listPreference, for example:
We will have at least 70 characters.
How can I do this from the code?
Any help is appreciated
Try like this..
Preference customPref = (Preference) findPreference("updates_interval");<-- your preferences key
customPref.setSummary("desired string");
here is a short example:
Preference etp = (Preference) findPreference("the_pref_key");
etp.setSummary("New summary");
This requires that you display your preferences either from a PreferenceActivity or from a PreferenceFragment, since findPreference() is a method of these classes. You most likely do that already.
To change the summary every time the user changes the actual preference, use a OnPreferenceChangeListener and check if the relevant key changed in the callback. After it has changed, just edit the summary like above.
You can create a subclass of ListPreference in which you set an OnPreferenceChangedListener from which you will have access to the new value, and set the text on your ListPreference. I think the setSummary() function on the ListPreference will update the text under the name of the preference. If that doesn't work you can also override getView() to implement your own custom view for the Preference on which you can set the text directly.
I am tryig to write an Android Honeycomb application and I am having trouble subclassing Preference: http://developer.android.com/reference/android/preference/Preference.html
I want to make a similar layout with title and summary but also a progress bar.
I have created the layout and added the custom preference class but I can't seem to get hold of the instance of it to set the values of the items in it.
It seems that the preference key doesn't work for the custom class.
Here is my preference definition compared to the standard preference class:
<Preference
android:key="int_free_storage"
android:title="Free Space"
android:summary="free storage value here"/>
<com.hamid.storageether.SpacePreference
android:key="int_space_test"
android:title="Test"
android:summary="This is my custom preference"/>
My my preference subclass then sets my XML layout as it's layout resource in its constructor
setLayoutResource(R.layout.space_pref_layout);
it also overrides the setTitle and setSummary methods....
In my main PreferenceActivity I try to get hold of my Preference by it's key but no luck it seems, since the preference never gets updated:
// These Two work
Preference intTotal = (Preference)findPreference("int_total_storage");
Preference intFree = (Preference)findPreference("int_free_storage");
intTotal.setSummary("Standard Preference Summary 1");
intFree.setSummary("Standard Preference Summary 2");
// My subclass doesn't - It just displays the default text defined in the layout xml.
SpacePreference intTest = (SpacePreference)findPreference("int_test_space");
intTest.setTitle("Testtttyyy");
intTest.setSummary("Test Summary");
Could someone please point me towards where I may be going wrong?
Is this code copied straight from the program or retyped? If copied, then your key is "int_space_test" in XML and "int_test_space" in code. It should be throwing a null pointer exception on the next line where you use intTest if that's the case.
I have a simple Preferences Activity that I populate via XML, defining the values as array resources.
In the MAIN Activity of the application, I get a handle to this via:
mSharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
In the XML for the only preference I have, which is a display setting, I have the following XML that defines the ListPreference:
<ListPreference
android:title="#string/pref_title_sort"
android:summary="#string/pref_summary_sort"
android:key="#string/pref_key_sort"
android:defaultValue="modified"
android:entries="#array/sort_order"
android:entryValues="#array/sort_order_values" />
You can see I am trying to set the default value to 'modified', which is a value found in #array/sort_order_values:
<string-array name="sort_order_values">
<item>modified</item>
<item>created</item>
<item>name</item>
</string-array>
However, when the Preferences Activity is launched, none of the items are selected by default.
I've tried adding the following line to my Activity, but it did not change anything (where pref_main is the XML file that defines the preferences):
PreferenceManager.setDefaultValues(this, R.xml.pref_main, false);
Any help appreciated!
Paul
Maybe You have just set a wrong value (without corresponding item in the value array) at the first time you run application. Now Android remembers your first choice. Try to manually uninstall app (Menu >> Settings >> Applications >> Manage Applications >> >> Uninstall ). This should help.