Develop Reference

Why onConfigurationChanged doesn't detect screen rotation?

I'm trying to use onConfigurationChanged to detect screen rotation.
Activity
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public void onConfigurationChanged(#NonNull Configuration newConfig) {
super.onConfigurationChanged(newConfig);
Toast.makeText(getApplicationContext(), "Screen is rotated!", Toast.LENGTH_SHORT).show();
Log.i("ROTATEAPP", "Screen is rotated...");
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<application
android:allowBackup="true"
android:dataExtractionRules="#xml/data_extraction_rules"
android:fullBackupContent="#xml/backup_rules"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.ScreenRotate"
tools:targetApi="31">
<activity
android:name=".MainActivity"
android:configChanges="orientation"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<meta-data
android:name="android.app.lib_name"
android:value="" />
</activity>
</application>
</manifest>
I rotated the device (Pixel 3 running Android 12) a few times, and didn't see any Toast or log entry. What's wrong here?

Incorrect Activity when running App Android Studio

I have starting building an app in Android studio. I have established the MainPage as the launcher activity in the manifest.xml.
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.AppCompat.NoActionBar">
<activity android:name=".MainPage">
android:screenOrientation="portrait"
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".courseSelect" />
<activity android:name=".profile1" />
<activity android:name=".stats1" />
<activity android:name=".ReviewRounds" />
<activity android:name=".ReferFriends" />
<activity android:name=".RangeMode" />
</application>
I have double checked that the run configuration is set to 'Default' and yet the app is running a different activity, entitled courseSelect. It is also not running some code correctly on the NumberPicker. Even though I've set the picker to have a min, max, and default, the picker only shows 0 and will not scroll. The two issues seem to be related somehow, in terms of what activity is being run.
this is the courseSelectCode:
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.NumberPicker;
import co.ceryle.segmentedbutton.SegmentedButtonGroup;
public class courseSelect extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_course_select);
//Hole Picker
NumberPicker holePicker = (NumberPicker)findViewById(R.id.holePicker);
holePicker.setMaxValue(18);
holePicker.setMinValue(1);
holePicker.setWrapSelectorWheel(false);
holePicker.setValue(1);
SegmentedButtonGroup sbg = (SegmentedButtonGroup) findViewById(R.id.segmentedButtonGroup);
sbg.setOnClickedButtonPosition(new SegmentedButtonGroup.OnClickedButtonPosition() {
#Override
public void onClickedButtonPosition(int position) {
// if(position == 0)
}
});
}
}
I tried to set the run configuration specifically to the MainPage activity and it still opens in the courseSelect Page.
EDIT: on request, here is my MainPage.java code:
public class MainPage extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_course_select);
Window g = getWindow();
g.setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION, WindowManager.LayoutParams.TYPE_STATUS_BAR);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
...
}

edit the Mainfest.xml, in order to enforce portrait layout there already:
<activity android:name=".MainPage"
android:screenOrientation="portrait"
android:configChanges="orientation|keyboardHidden">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
...which makes this code merely useless (styles.xml can also be used for window styles):
Window g = getWindow();
g.setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION, WindowManager.LayoutParams.TYPE_STATUS_BAR);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
also update setContentView( R.layout.activity_course_select ); to the proper resource.
because it starts the MainPage Activity, but then inflates the wrong XML file.
one "suggested edit" before was to swap the order of setContentView() and the paragraph below ...which I've rejected, because setting it in Manifest.xml appeared more organized (less code).

First of all There is a mistake in your manifest file
you wrote screenOrientation attribute outside the opening tag
<activity android:name=".MainPage">
android:screenOrientation="portrait"
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
it should be
<activity
android:name=".MainPage"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
and you used wrong xml to setContenView

Try this and error was in 9th line because your code line is outside of the tag:
<activity android:name=".MainPage">
android:screenOrientation="portrait" // error
Do this :
<activity android:name=".MainPage"
android:screenOrientation="portrait"> // After doing this no error
and do also this thing :
public class MainPage extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_course_select); // error
do this :
public class MainPage extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.MAIN_PAGE_ACTIVITY_NAME); // no error

Your launcher activity is MainPage but you are calling the layout of courseselect activity inside MainPage activity's onCreate method on this line
setContentView(R.layout.activity_course_select);
Change it to your MainPage layout
setContentView(R.layout.yourMainPageLayout);

ListFragment does not show title bar in Android Studio

Why title bar not show it in the ListFragment?
I did not set fullscreen or other.Please help me
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".CrimeListActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity
android:name=".CrimePagerActivity"
android:label="#string/app_name">
</activity>
</application>
CrimeListFragment.java
public class CrimeListFragment extends ListFragment {
private ArrayList<Crime> mCrimes;
private static final String TAG = "CrimeListFragment";
private Crime c;
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
getActivity().setTitle(R.string.crimes_title);
mCrimes = CrimeLab.get(getActivity()).getCrimes();
CrimeAdapter adapter = new CrimeAdapter(mCrimes);
setListAdapter(adapter);
...
}
}

Check, if there isn't for example "AppTheme.NoActionBar" as your app theme at Design, in your fragment xml file.

change the theme of your activity in manifest.
android:theme=""

Hide Action Bar for Splash Screen

I'm trying to create splash screen without action bar.
Firstly before created splash screen, action bar in main activity and when I create splash screen, action bar comes to splash screen and main activity is full screen. I searched method like getwindow(), getActionBar(), but when I use these method program says to me unfortunately stopped. So what I'm missing?
How can I avoid actionBar in splash screen?
My code:
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash_item);
Thread th=new Thread(){
public void run(){
try {
sleep(4000);
Intent intent=new Intent(MainActivity.this,SplashScreen.class);
startActivity(intent);
} catch (Exception e) {
e.printStackTrace();
}
finally{
finish();
}
}
};
th.start();
}
MANİFEST:
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".SplashScreen"
android:label="#string/app_name"
>
<intent-filter>
<action android:name="android.intent.action.SPLASHSCREEN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>

First, import the support library in the top of your app:
import android.support.v7.app.ActionBarActivity;
and change your code as follows:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash_item);
getSupportActionBar().hide();
}

Using AppCompat for being supported for all versions:
<activity
android:theme="#style/Theme.AppCompat.Light.NoActionBar">

requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
Put that before your setContentView(...), should get the job done.

For Android 3.0 or higher use ActionBarAPI#hide
For lower versions you will need to use Android Support Library.
Use ActionBar as
ActionBar actionBar = getSupportActionBar();
actionBar.hide();
Ref docs
Also if your requirement in static, then you can choose a theme for your activity that dos not have actionbar such as
android:theme="#android:style/Theme.Holo.Light.NoActionBar"
You can do this as:
<activity android:theme="#android:style/Theme.Holo.Light.NoActionBar"
android:name=".name_here"
android:label="#string/app_name" >

use a style without actionbar, also in your splash screen activity java extend Activity and make the splash screen your MAIN activity and in this activity you call an Intent to open your MainActivity after some seconds
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
</activity>
<activity android:theme="#android:style/Theme.Holo.Light.NoActionBar"
android:name=".SplashScreen"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Example:
In your SplashScreen activity write this code. This will open your MainActivity after 2 seconds.
new Handler().postDelayed(new Runnable()
{
public void run()
{
Intent localIntent = new Intent(SplashScreen.this, MainActivity.class);
SplashScreen.this.startActivity(localIntent);
SplashScreen.this.finish();
}
}, 2000L);

This is the simplest method.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
}
where R.layout.activity_main is replaced by your layout activity e.g. activity_splash

How to change title of Activity in Android?

I am using
Window w = getWindow();
w.setTitle("My title");
to change title of my current Activity but it does not seem to work.
Can anyone guide me on how to change this?

Try setTitle by itself, like this:
setTitle("Hello StackOverflow");

Just an FYI, you can optionally do it from the XML.
In the AndroidManifest.xml, you can set it with
android:label="My Activity Title"
Or
android:label="#string/my_activity_label"
Example:
<activity
android:name=".Splash"
android:label="#string/splash_activity_title" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

If you want it one time & let system handle the rest (not dynamic) then do like this in your manifest file:
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name_full" > //This is my custom title name on activity. <- The question is about this one.
<intent-filter android:label="#string/app_launcher_name" > //This is my custom Icon title name (launcher name that you see in android apps/homescreen)
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

setTitle(getResources().getText(R.string.MyTitle));

There's a faster way, just use
YourActivity.setTitle("New Title");
You can also find it inside the onCreate() with this, for example:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
this.setTitle("My Title");
}
By the way, what you simply cannot do is call setTitle() in a static way without passing any Activity object.

This worked for me.
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment, container, false);
getActivity().setTitle("My Title");
//...
}

If you have multiple activities, you can set it like this in AndroidManifest.xml
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".NumbersActivity"
android:label="#string/category_numbers"
android:theme="#style/category_numbers" />
<activity
android:name=".FamilyActivity"
android:label="#string/category_family"
android:theme="#style/category_family" />
<activity
android:name=".ColorsActivity"
android:label="#string/category_colors"
android:theme="#style/category_colors" />
<activity
android:name=".PhrasesActivity"
android:label="#string/category_phrases"
android:theme="#style/category_phrases" />
<activity
android:name=".ExperimentActivity"
android:label="#string/category_experiment"
android:theme="#style/category_experiment" />
</application>

I'm using Android Studio 3.0.1.
WIth an Activity:
setTitle("Title Text");
Inside a fragment:
getActivity().setTitle("Title Text");

#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.Main_Activity);
this.setTitle("Title name");
}

If you want to set title in Java file, then write in your activity onCreate
setTitle("Your Title");
if you want to in Manifest then write
<activity
android:name=".MainActivity"
android:label="Your Title" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

In Kotlin, this way:
this.title = resources.getText(R.string.fast_learning)

I have a Toolbar in my Activity and a Base Activity that overrides all Titles. So I had to use setTitle in onResume() in the Activity like so:
#Override
protected void onResume() {
super.onResume();
toolbar.setTitle(R.string.title);
}

The code helped me change the title.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_name);
ActivityName.this.setTitle("Your Activity Title");}

Inside a MainActivity:
public class act1 extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act1);
setTitle("First Activity");
}
}

setTitle("Whatever apps");
in MainActivity.java is simplier
I would say.

If you want to change Title of activity when you change activity by clicking on the Button. Declare the necessary variables in MainActivity:
private static final String TITLE_SIGN = "title_sign";
ImageButton mAriesButton;
Add onClickListener in onCreate() and make new intent for another activity:
mTitleButton = (ImageButton) findViewById(R.id.title_button);
mTitleButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this,
SignActivity.class);
String title_act = getText(R.string.simple_text).toString();
intent.putExtra("title_act", title_act);
startActivity(intent);
finish();
}
});
SecondActivity code in onCreate():
String txtTitle = getIntent().getStringExtra("title_act");
this.setTitle(txtTitle);

If you're using onCreateOptionsMenu, you can also add setTitle code in onCreateOptionsMenu.
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu, menu);
setTitle("Neue Aktivität");
return true;
}

setTitle("Welcome Activity");