I have an fullscreen apllication. I'm using requestWindowFeature(Window.FEATURE_NO_TITLE) to remove the title. This works very well for my 4.1.2 Smartphone and the 4.4.2 Emulator.
In the 2.2 Emulator, on my 2.2 Smartphone and on my 2.3.6 tablet the title is still being displayed. I tried very much things like changing styles in the Manifest or editing those styles in the styles.xml, nothing works.
Here's my onCreate():
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
GameData.display = new Display(this);
setContentView(GameData.display);
CoreData.mainActivity = this;
NetworkData.init();
}
If you want to remove the title, just add this style into your manifest file.
android:theme="#style/Theme.Black.NoTitleBar"
then the problem arises, notifying that you must use a derivative of an appcompat library. this is because you are using the support library v7, & on creating your project, an activity creates which doesn't extends as an Activity class, but ActionBarActivity class.
so, if you really want to use the support library, create the theme that you created under values, values-v11, values-v14 folders & apply your theme on your manifest.
else, change your ActionBarActivity class into Activity class & apply Theme.Black.NoTitleBar theme to your manifest.
hope that it helps.
I am new to android i made a project but every I create a project class it extends actionbaractivity always created, instead of extends activity before it was extends activity every time I created a class, maybe i press something But i dont really know what happned.
This is the result and actionbarActivity is error
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
If you set up your project to target API < 11 there will be checkboxes for certain support features. ActionBar, GridLayout, Fragments, and NavDrawer. If you check ActionBar the activity that is generated will extend ActionBarActivity (which is the support version of a fragment activity) It may be confusing at first but it's all in the name of supporting older versions of Android with the latest features.
http://developer.android.com/reference/android/support/v7/app/ActionBarActivity.html
If you set your minimum required SDK below 11 it will create the application like this because in API level below 11 there is no ActionBar. The default value is 8. You should set it 14 and then you can change it in your AndroidManifest.xml file.
I'm trying to add the actionbar of Android(4.0) to the webview activity of PhoneGap (2.0.0). I'm using the same actionbar in another activity in my application. It's in the menu.xml file and in the other activity everything is working without any problem.
When I load the webview, the actionbar is not shown.
I get a nullPointerExeption on the actionbar. I already have the #targetApi(14). And the resource is working for the homeactivity but not for the webviewactivity.
ActionBar actionBar = getActionBar();
actionBar.setBackgroundDrawable(getResources().getDrawable(R.drawable.bar));
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setIcon(R.drawable.logo);
I found getActionBar is a function from the Activity class and this is returning null. Probably phonegap is giving a twist to the activty and therefore it is not possible to load the actionbar.
Anybody experience with this? Thanks
#Override
public void onCreate(Bundle savedInstanceState) {
super.setBooleanProperty("showTitle", true);
super.onCreate(savedInstanceState);
The setBooleanProperty before super.onCreate was the answer for the problem
I'm having an odd problem.
I am making an app with targetsdk 13.
In my main activity's onCreate method i call getActionBar() to setup my actionbar. This works fine when running on the Android 3.2 emulator, but when using Android 3.0 and 3.1 the getActionBar() method returns null.
I find this extremely odd, and i cannot see any reason why it would do so.
Is this a bug with the emulators or is there something i need to do, in order to ensure that my application has an actionbar?
SOLUTION:
I think I've found a solution for this problem.
I wasn't using the setContentView to set a layout for the activity. Instead I was using fragmentTransaction.add(android.R.id.content, mFragment, mTag) to add a fragment to the activity.
This worked fine in 3.2, but in earlier honeycomb versions the action bar is apparently not set if you don't use the setContentView in the onCreate() method.
So I fixed it by using the setContentView() method in my onCreate() method and just supplying it with a layout that contained an empty FrameLayout.
I can still use the fragmentTransaction.add(android.R.id.content, mFragment, mTag) method the same way as before.
It's not the prettiest fix, but it works.
Can use getSupportActionBar() instead of getActionBar() method.
If you are using the support library
import android.support.v7.app.ActionBarActivity;
public class MainActivity extends ActionBarActivity {
use getSupportActionBar() instead of getActionBar()
* Update:
The class ActionBarActivity now is deprecated:
import android.support.v7.app.ActionBarActivity;
I recommend to use:
import android.support.v7.app.AppCompatActivity
if you are using android.support.v7.app.AppCompatActivity
public class HomeActivity extends AppCompatActivity {
Then you should be using android.support.v7.app.ActionBar
ActionBar ab = getSupportActionBar();
If you are using android.support.v4.app.FragmentActivity
public class HomeActivity extends FragmentActivity {
then you should be using android.app.ActionBar
ActionBar ab = getActionBar();
If you are using android.support.v7.app.ActionBarActivity
public class HomeActivity extends ActionBarActivity {
you should be using android.support.v7.app.ActionBar
ActionBar ab = getSupportActionBar();
You have to define window type as actionbar before activity render its view.
use
requestWindowFeature(Window.FEATURE_ACTION_BAR);
before calling setContentView() method.
I faced the above issue where getActionBar() method returns null. I was calling the getActionBar() after setting the setContentView() and still its returning a null.
I resolved the issue by setting the min-sdk version in Android Manifest file that was missing initially.
<uses-sdk android:minSdkVersion="11" />
ActionBar needs application or activity's Theme to have an app title. Make sure you have not styled your application or activity as Theme.NOTITLE.
<application
android:name="com.xxx.yyy"
android:debuggable="false"
android:icon="#drawable/icon"
android:label="#string/app_name"
android:theme="#style/Theme.NoTitle"> // remove this line if you have this in your code
<activity
android:name="com.xxx.yyy.Activity"
android:configChanges="orientation|keyboardHidden|screenSize"
android:theme="#style/Theme.NoTitle" // remove this line if you have in your code
android:windowSoftInputMode="adjustResize|stateHidden" >
import android.support.v7.app.AppCompatActivity;
then
extends AppCompatActivity
then use
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
This answer is late but might be helpful to anyone who arrives from Google: You might well need to declare
<item name="android:windowActionBar">true</item>
in your styles.xml. It seems false can be the default. You also need to be on API 11 or higher.
More details can be found in the documentation here. Specifically, quote:
Tip: If you have a custom activity theme in which you'd like to remove
the action bar, set the android:windowActionBar style property to
false. However, if you remove the action bar using a theme, then the
window will not allow the action bar at all, so you cannot add it
later—calling getActionBar() will return null.
I had the same problem and one of the solutions was to use setContentView() before calling getActionBar().
But there was another thing that fixed the problem. I specified theme for the application to be #android:style/Theme.Holo.Light.
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#android:style/Theme.Holo.Light" >
...
</application>
I think any theme, which has <item name="android:windowActionBar">true</item> in it, can be used.
The main reason for that is using themes that are not supporting ActionBar:
In manifest file add the following either in your target activity or application element (if you want to unify the theme over whole application)
Examples of themes that are supporting action bar "Theme.AppCompat.Light" or "Theme.Holo.Light" ...
android:theme="#android:style/Theme.Holo.Light"
It is better to put all styles in styles.xml and use it everywhere using "#style/themName" so the previous one will be
android:theme="#style/AppTheme"
and styles.xml will have the following:
<style name="AppTheme" parent="Theme.AppCompat.Light">
Hints:
There is some themes that can not be used in old SDKs like "#android:style/Theme.Holo.Light.DarkActionBar" is not supported before SDKs version 14.
To allow your app to support minimum specific version of SDK you could add the following under <app> element:
<uses-sdk android:minSdkVersion="14" />
To specify min SDK version in AndroidStudio, you could by using app's Gradle file.
android{
defaultConfig{
minSdkVersion 14
targetSdkVersion 21
}
}
I ran into this problem . I was checking for version number and enabling the action bar only if it is greater or equal to Honeycomb , but it was returning null. I found the reason
and root cause was that I had disabled the Holo Theme style in style.xml under values-v11 folder.
go to the AndroidManifest.xml and replace
android:theme="#style/AppTheme"
by
android:theme="#android:style/Theme.Holo.Light.DarkActionBar"
Use getSupportActionBar() instead of getActionBar()
In my case, I had this in my code which did not work:
#Override
protected void onCreate(Bundle savedInstanceState) {
context = getApplicationContext();
requestWindowFeature(Window.FEATURE_ACTION_BAR);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
Then I played with the order of the code:
#Override
protected void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_ACTION_BAR);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = getApplicationContext();
}
And it worked!
Conclusion: requestWindowFeature should be the first thing you call in the onCreate method.
I had the same issue. It solved by chaning App theme in styles.xml
Before
<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
After
<!-- Base application theme. -->
<style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">
One thing I wanted to add since I just ran into this, if you are trying to getActionBar() on an Activity that has a parent, it will return null. I am trying to refactor code where my Activity is contained inside an ActivityGroup, and it took a good few minutes for me to go "oh duh" after looking at the source of how an ActionBar gets created in source.
I solve it by this changes:
change in minifest android:theme="#android:style/Theme.Holo.Light" >
add to class extends ActionBarActivity
add import to class import android.support.v7.app.ActionBarActivity
To add to the other answers:
Make sure you call setActionBar() or setSupportActionBar() in your onCreate() method before calling the getActionBar():
Define some Toolbar in your activity.xml, then in the onCreate():
Toolbar toolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(toolbar);
// Now you can use the get methods:
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
In my case I simply had to extend AppCompatActivity instead of Activity
supportActionBar?.setDisplayHomeAsUpEnabled(true)
Full activity example class:
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
//class LocationFound : Activity() { <-----Does not seem to work with ActionBar in recent versions
class LocationFound : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_location_found)
supportActionBar?.setDisplayHomeAsUpEnabled(true)
} }
On Versions
minSdkVersion 22
targetSdkVersion 29
I know I am late to the party (and new to Android) on this question but I found the information here very helpful and thought I should add the findings of my own endeavours with getting ActionBar to work as I wanted in case others like me come looking for help.
I have a widget which is a floating window with no window title. I use a style theme to implement android:windowIsFloating, android:backgroundDimEnabled and android:windowNoTitle. The widget worked fine until I wanted to add a button that called a fragment pager with several list fragment pages and used the ActionBar. It would crash on the pager activity with a null pointer exception. I narrowed it down to the ActionBar being null. Following the findings of previous people who contributed to this thread I removed my theme from the manifest file and the ActionBar worked fine but now my window now longer floated (it was fullscreen) and it had a page title I did not want.
Further research took me to the Styles and Themes API Training Guide which led me to a solution. I discovered I could add my custom theme to individual activities in the manifest file whereas before I was applying it to the application. All my windows now have the desired appearance.
Try extending your Activity class from ActionBarActivity. This solved it for me. Do something like the following:
public class MyActivity extends ActionBarActivity
{
. . .
In my case the class was extending only from Activity.
This may also help some people.
In my case, it was because I had not defined a context in the menu.xml
Try this:
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.example.android.ActionBarActivity">
Instead of this:
<menu xmlns:android="http://schemas.android.com/apk/res/android">
Just check the implementation of source code by command click:
private void initWindowDecorActionBar() {
Window window = getWindow();
// Initializing the window decor can change window feature flags.
// Make sure that we have the correct set before performing the test below.
window.getDecorView();
if (isChild() || !window.hasFeature(Window.FEATURE_ACTION_BAR) || mActionBar != null) {
return;
}
mActionBar = new WindowDecorActionBar(this);
mActionBar.setDefaultDisplayHomeAsUpEnabled(mEnableDefaultActionBarUp);
mWindow.setDefaultIcon(mActivityInfo.getIconResource());
mWindow.setDefaultLogo(mActivityInfo.getLogoResource());
}
requestWindowFeature(Window.FEATURE_ACTION_BAR); Fixed my issue as I saw requestWindowFeature(Window.FEATURE_ACTION_BAR) is failing; code is open source use it !!
android.support.v7.app.ActionBar actionBar = getSupportActionBar();
works pretty quickly
If calling this method from Fragment the make sure to call this in onActivityCreated()