Develop Reference

How to Get Apps to Show Full Screen on Chromebook?

I've been making Android apps for a long time and can get them to open in full screen mode on every device except Chromebook. No matter what I do, they only open about half screen and a user has to click the "maximize" button to get them to open further.
Here is the code I use to try to get the apps full screen:
<item name="android:windowFullscreen">true</item>
in the relevant style in themes.xml
as well as
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
in MainActivity's onCreate() method.
I've also tried putting
android:theme="#android:style/Theme.NoTitleBar.Fullscreen"
in the application block of AndroidManifest.xml.
Is there something else I can do to get the apps to open full screen on Chromebook?
(I'm using HP Chromebook x360, if that helps)

So there is a section of the Android documentation for using Android on ChromeOS which makes reference to Window Management - Launch Size which seems appropriate.
Quoting from the documentation:
Use a launch size only in desktop environments. This helps the window manager to give you the proper bounds and orientation. To indicate a preferences when used in desktop mode, add the following meta tags inside the <activity>:
<meta-data android:name="WindowManagerPreference:FreeformWindowSize"
android:value="[phone|tablet|maximize]" />
<meta-data android:name="WindowManagerPreference:FreeformWindowOrientation"
android:value="[portrait|landscape]" />
Use static launch bounds. Use inside the manifest entry of your activity to specify a "fixed" starting size. See this example:
<layout android:defaultHeight="500dp"
android:defaultWidth="600dp"
android:gravity="top|end"
android:minHeight="450dp"
android:minWidth="300dp" />
Use dynamic launch bounds. An activity can create and use ActivityOptions.setLaunchBounds(Rect) when creating a new activity. By specifying an empty rectangle, your app can be maximized.
Note: These options work only if the activity started is a root activity. You can also do this using a springboard activity to clear the activity stack in the task with a new start.

How to add app icon properly in android react-native

Hi I added icons to android/app/src/main/res/..., the app icon showing perfectly in home screen like first image, but when minimize the app it showing default app icon like second image. how can change that icon also.
I cleaned build folder, gradlew and reinstalled the app but no changes.
Please help me on this

put this on AndroidManifest.xml and try
<application
...
android:icon="#drawable/ic_launcher"
...
</application>
also hope you update the icons properly. please refer this
https://code.tutsplus.com/tutorials/how-to-update-the-launcher-icon-for-your-android-app--cms-30624

I'm not sure if this comes after you setup androidManifest.xml but you will need icons in these two folders:
android/app/src/main/res/mipmap.
ios//Images.xcassets/AppIcon.appiconset
I've used the resize-reactnative-launcher-icon shell scrip to generate my icons. It takes a png image and creates the 25 variations you need by size and resolution.
bash resize.sh my-cool-new-app-logo.png

cordova/phonegap has quick loading screen on android

When ever I load my app on android I get a grey screen with the words "player needed"(the apps name) across the top for about a second before my app actually starts. It does not appear on the development testing app only when I do an actual build, and then only when I start the app. If I change windows back and forth it does not appear again. How can I remove this?example of grey screen
Thank you!

You could try this, worked for me, it's something about the MainActivity theme on Android.
In the "platforms\android" folder under your project, open the AndroidManifest.xml and search for android:theme inside the <activity> tag that contains android:name="MainActivity" and change the default value (that is android:theme="#android:style/Theme.DeviceDefault.NoActionBar") to android:theme="#android:style/Theme.Translucent". Save the file and build your project again, the grey screen should desapear.

Android full screen without three dots

I create empty app. I want set full screen without three dots(menu/search/back).
Please help!

Set in the manifest
<activity android:theme="#android:style/Theme.NoTitleBar.Fullscreen" .... >

If you use a tablet you cannot get rid of the system bar. You may be able to get rid of the navigation bar and status bar on phones. Please read the "Controls for system UI visibility" section of the Android 4.0 SDK release notes. http://developer.android.com/sdk/android-4.0.html

Configure Android Activity full screen with white background color

I'm pretty much new to Android application development. I want my first Activity to display in full screen with white background. How can I do that?

Add following attribute to your Activity in Android Manifest file
android:theme="#android:style/Theme.Light.NoTitleBar.Fullscreen"