Develop Reference

Android - DropDownPreference not working in Landscape orientation

I have a pretty weird issue. In my SettingsActivity, I have a DropDownPreference (the one that displays a list when clicked), and it works fine on Portrait mode.
However, when I go into Landscape mode, whenever the preference is clicked, it quickly disappears after being displayed, as if I had pressed the screen twice.
Here is my style, although I doubt there's something to do with it:
<style name="SettingsFragment">
<item name="android:navigationBarColor">?navBackground</item>
<item name="android:statusBarColor">?colorPrim</item>
<item name="android:colorBackground">?colorPrim</item>
<item name="android:colorForeground">?textForeground</item>
<item name="android:textColor">?textForeground</item>
<item name="alertDialogTheme">#style/DialogTheme</item>
<item name="colorAccent">?accentVariant</item>
<item name="preferenceCategoryTitleTextColor">?accentVariant</item>
</style>
Notes: My phone is a Samsung Galaxy Note 10, running Android 12 (API 31).
EDIT: Posting the activity's source code:
public class SettingsActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
ActivityUtils.applyTheme(this);
getTheme().applyStyle(R.style.SettingsFragment, true);
super.onCreate(savedInstanceState);
setContentView(R.layout.settings_activity);
if (savedInstanceState == null) {
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.settingsContainer, new SettingsFragment())
.commit();
}
}
public static class SettingsFragment extends PreferenceFragmentCompat {
#Override
public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
setPreferencesFromResource(R.xml.settings, rootKey);
}
}
}
PS: Parent theme does not change any attributes aside colors.

Cannot hide/remove an Activity's title

I cannot hide the title's view from an Activity that I'm styling as a Dialog.
android:windowNoTitle is set to false in the reference style, and RequestWindowFeature(WindowFeatures.NoTitle) is called from OnCreate.
Is there another setting for completely removing the title's view from an Activity?
styles.xml
<style name="Theme.AppCompat.Light.Dialog_Configuration" parent="Theme.AppCompat.Light.Dialog">
<item name="android:windowNoTitle">true</item>
<item name="android:windowCloseOnTouchOutside">false</item>
</style>
ConfigurationView
[Activity(
Label = "Configuration",
MainLauncher = false,
Theme = "#style/Theme.AppCompat.Light.Dialog_Configuration",
ExcludeFromRecents = true
)]
public class ConfigurationView : AppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
RequestWindowFeature(WindowFeatures.NoTitle);
SetContentView(Resource.Layout.Configuration);
}
}

Are you using toolbar? You can try this
getSupportActionBar().setDisplayShowTitleEnabled(false);
or
requestWindowFeature(Window.FEATURE_NO_TITLE);//will hide the title.
getSupportActionBar().hide(); //hide the title bar.

While you have removed the title, you also need to remove the title bar as well. Try adding the following line to your onCreate method:
getSupportActionBar().hide();

Write this in the OnCreate method just after SetContentView:
ActionBar.Hide();
Alternatively, you could try this
NavigationPage.SetHasNavigationBar(this, false);

Android - Using AppCompat/ActionBar for older devices(java.lang.NullPointerException)

I have an application which currently works on Android versions 4.x and more.
I am trying to change it so it can be usable by older devices such as 2.x and more.
Everything is working fine except the action bar. I am getting a null pointer exception every time I am trying to getSupportActionBar. This is am issue that have been discussed a lot in forums but I still cannot solve it.
The application uses the appCompat library but it does not seem to work on older devices.
styles.xml file
<style name="AppBaseTheme" parent="Theme.MyApp">
<item name="android:spinnerItemStyle">#style/SpinnerItem</item>
<item name="android:spinnerDropDownItemStyle">#style/SpinnerItem.DropDownItem</item>
<item name="android:windowNoTitle">true</item>
</style>
MyApp.xml file
<style name="Theme.MyApp" parent="#style/Theme.AppCompat">
<item name="actionBarItemBackground">#drawable/selectable_background</item>
<item name="popupMenuStyle">#style/PopupMenu.MyApp</item>
<item name="dropDownListViewStyle">#style/DropDownListView.MyApp</item>
<item name="actionBarTabStyle">#style/ActionBarTabStyle.MyApp</item>
<item name="actionDropDownStyle">#style/DropDownNav.MyApp</item>
<item name="actionBarStyle">#style/ActionBar.Transparent.MyApp</item>
<item name="actionModeBackground">#drawable/cab_background_top</item>
<item name="actionModeSplitBackground">#drawable/cab_background_bottom</item>
<item name="actionModeCloseButtonStyle">#style/ActionButton.CloseMode.MyApp</item>
Activity trying to get the actionbar
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_auction_list);
if (android.os.Build.VERSION.SDK_INT >=11)
{
getActionBar().setIcon(R.drawable.gem);
getActionBar().setDisplayHomeAsUpEnabled(false);
this.getActionBar().setDisplayShowCustomEnabled(true);
this.getActionBar().setDisplayShowTitleEnabled(false);
LayoutInflater inflator = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflator.inflate(R.layout.actionbar_title, null);
((CFTextView)v.findViewById(R.id.actionbarTitle)).setText(this.getTitle());
//assign the view to the actionbar
this.getActionBar().setCustomView(v);
}
else
{
//This calls a private class inside the same class to get a supported action bar
notActionBar nab = new notActionBar();
nab.getNotActionBar(); //THIS IS THE ERROR LINE
}
Private class that gets the supported action bar. I have used a private class instead of directly getting the actionbar because i could not extend the ActionBarActivity because the activity all ready extends fragments.
private class notActionBar extends ActionBarActivity {
public void getNotActionBar(){
ActionBar actionBar = getSupportActionBar(); //NULL POINTER EXCEPTION
actionBar.setIcon(R.drawable.gem);
actionBar.setDisplayHomeAsUpEnabled(false);
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
actionBar.setDisplayShowCustomEnabled(true);
this.getSupportActionBar().setDisplayShowCustomEnabled(true);
this.getSupportActionBar().setDisplayShowTitleEnabled(false);
LayoutInflater inflator = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflator.inflate(R.layout.actionbar_title, null);
((CFTextView)v.findViewById(R.id.actionbarTitle)).setText(this.getTitle());
//assign the view to the actionbar
this.getSupportActionBar().setCustomView(v);
}
public void setTitleActionBar(String a){
getSupportActionBar().setTitle(a);
}
}

you should not try to instantiate Activities like this in Android:
notActionBar nab = new notActionBar();
the way to start Activities in Android is with startActivity(Intent intent) or startActivityForResult method.
But anyhow, The solution for your Problem should be extending ActionBarActivity instead FragmentActivity in your main Activity.
You can do this also if you use Fragments! Because ActionBarActivity extends FragmentActivity.
see related answer here

You should also consider using only getSupportActionBar() or getActionBar() either one of them. Since you wanna target earlier version, use only getSupportActionBar() and remove all the refernces to getActionBar() from your code.
A complete guide to Action Bar is here.

Android: Apply different themes to fragments of one activity

What I want to do:
I want each Fragment of my MainActivity to use a different theme, so that the ActionBar has different background-colors, depending on the visible Fragment.
The Situation:
I created a MainActivity which uses the Tabs + Swipe Navigation. I Added 7 Tabs (=7 Fragments). I created one Theme which should be applied only to the first Fragment (fragment_main_1).
Here the Theme:
<resources xmlns:android="http://schemas.android.com/apk/res/android">
<style name="Blue" parent="android:Theme.Holo.Light">
<item name="android:actionBarStyle">#style/Blue.ActionBarStyle</item>
</style>
<style name="Blue.ActionBarStyle" parent="android:Widget.Holo.Light.ActionBar">
<item name="android:titleTextStyle">#style/Blue.ActionBar.TitleTextStyle</item>
<item name="android:background">#33B5E5</item>
</style>
<style name="Blue.ActionBar.TitleTextStyle" parent="android:TextAppearance.Holo.Widget.ActionBar.Title">
<item name="android:textColor">#FFFFFF</item>
</style>
</resources>
After creating 6 more Themes it should be possible to swipe through the Tabs while the ActionBar changes its background-color automatically.
What didn't work:
Adding those lines (which I found here on stackoverflow) to the Fragment1.java:
// create ContextThemeWrapper from the original Activity Context with the custom theme
final Context contextThemeWrapper = new ContextThemeWrapper(getActivity(), R.style.Blue);
// clone the inflater using the ContextThemeWrapper
LayoutInflater localInflater = inflater.cloneInContext(contextThemeWrapper);
// inflate the layout using the cloned inflater, not default inflater
return localInflater.inflate(R.layout.fragment_main_1,container, false);
I hope you can help me:) Thank you.

Many fragments (such as PreferenceFragment) read the styled attributes directly from the Context returned by Fragment.getContext() method, so you might need to override that too:
private var themedContext: Context? = null
override fun onAttach(context: Context) {
super.onAttach(context).also {
themedContext = ContextThemeWrapper(context, R.style.ThemeForThisFragment)
// if you want to apply a theme overlay:
// themedContext.theme.applyStyle(R.style.MyThemeOverlay, true)
}
}
override fun onDetach() {
super.onDetach()
themedContext = null
}
override fun getContext(): Context? {
return themedContext ?: super.getContext()
}

Try LayoutInflater localInflater = inflater.from(contextThemeWrapper); instead.

How to set the title of DialogFragment?

This should be a simple task, but for some reason I can find a way to set the title of a DialogFragment. (I am setting the dialog contents using onCreateView overload).
The default style leaves a place for the title, but I can't find any method on the DialogFragment class to set it.
The title is somehow magically set when the onCreateDialog method is used to set the contents, so I wonder if this is by design, or there is a special trick to set it when using the onCreateView overload.

You can use getDialog().setTitle("My Dialog Title")
Just like this:
public static class MyDialogFragment extends DialogFragment {
...
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Set title for this dialog
getDialog().setTitle("My Dialog Title");
View v = inflater.inflate(R.layout.mydialog, container, false);
// ...
return v;
}
// ...
}

Does overriding onCreateDialog and setting the title directly on the Dialog work? Like this:
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
Dialog dialog = super.onCreateDialog(savedInstanceState);
dialog.setTitle("My Title");
return dialog;
}

Jason's answer used to work for me, but now it needs the following additions to get the title to show.
Firstly, in your MyDialogFragment's onCreate() method, add:
setStyle(DialogFragment.STYLE_NORMAL, R.style.MyDialogFragmentStyle);
Then, in your styles.xml file, add:
<style name="MyDialogFragmentStyle" parent="Theme.AppCompat.Light.Dialog.Alert">
<item name="windowActionBar">false</item>
<item name="windowNoTitle">false</item>
<item name="android:windowActionBar">false</item>
<item name="android:windowNoTitle">false</item>
</style>
After hours of trying different things, this is the only one that has done the trick for me.
NB - You may need to change the Theme.AppCompat.Light.Dialog.Alert to something else in order to match the style of your theme.

DialogFragment could be represented as dialog and as Activity. Use code below that would work properly for both
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
if (getShowsDialog()) {
getDialog().setTitle(marketName);
} else {
getActivity().setTitle(marketName);
}
}

You can take a look at the official docs.
The way i did is like this:
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity())
.setTitle("My Title");
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.my_layout, null);
builder.setView(view);
return builder.create();
}

Similar to Ban Geoengineering's answer, but with a few modifications, so instead of coding what specific theme to use in the DialogFragment, I override the default style used by DialogFragments in my styles.xml.
set the title in the androidx.fragment.app.DialogFragment.
class EditBatteryLevelFragment:DialogFragment(),SelfClosingFragment.Host
{
override fun onCreateView(
inflater:LayoutInflater,container:ViewGroup?,savedInstanceState:Bundle?
):View
{
// set dialog title
requireDialog().setTitle(R.string.edit_battery_level__title)
// .....
return someView
}
}
in your app theme in styles.xml, override android:dialogTheme, which is the default style used by DialogFragment instances.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="AppTheme" parent="Theme.MaterialComponents">
<!-- BONUS READING: override material colors here, too https://material.io/develop/android/theming/color -->
<!-- override DialogFragment theme of those spawned by activities with this theme -->
<item name="android:dialogTheme">#style/AppTheme.Dialog</item>
</style>
<!-- ... -->
also in styles.xml, declare the dialog theme that will be used by DialogFragment instances. it's important for this style to inherit from ThemeOverlay so that it will preserve your app's theme colors.
<!-- ... -->
<!-- define the style for your dialog -->
<style name="AppTheme.Dialog" parent="ThemeOverlay.MaterialComponents.Dialog">
<!-- add a minimun width to the dialog, so it's not too narrow -->
<item name="android:windowMinWidthMajor">#dimen/abc_dialog_min_width_major</item>
<item name="android:windowMinWidthMinor">#dimen/abc_dialog_min_width_minor</item>
<!-- display the title for dialogs -->
<item name="android:windowNoTitle">false</item>
</style>
</resources>
make sure that the activity that is spawning the DialogFragment is using the defined AppTheme.

If you are using view binding:
#NonNull
#Override
public Dialog onCreateDialog(#Nullable Bundle savedInstanceState) {
binding = YourDialogXmlBinding.inflate(getLayoutInflater());
AlertDialog.Builder builder = new AlertDialog.Builder(requireActivity());
builder.setTitle("Your title here")
.setView(binding.getRoot());
return builder.create();
}