How to turn on or turn off the lamp in your Android

To turn on the lamp, repeat

Ok Google, Lumos Maxima 

To turn off the lamp, repeat

Ok Google, Nox 

How to Enable the Hidden System UI Tuner Menu in Android Marshmallow

To enable the new hidden menu follow these steps.

Roll down the menu and press for some seconds the roller button:

How to retrieve the IMEI of your Phone

To retrieve the IMEI of your phone there are two way

Secret code of your Android Phone

Incredible, here the list of the secret code of the Andorid Phone:

Decompile Android’s DEX File

Android uses a DEX archive in place of JAR. Also, the Java classes are compiled differently.
To decompile the classes, you need to go through a few extra steps.

What Will You Need?

Dex2Jar from http://code.google.com/p/dex2jar/
A regular Java decompiler, such as JD (please, search "java decompiler" on google)

The Steps

First, extract the .apk file of the Android application.

jar  xvf  HelloWorld.apk

(in alternative you can use the 7zip program)

You will notice classes.dex file in the extracted folder.

Next, run dex2jar to convert the classes.dex file to a JAR file.

(you can extract the dex2jar file in the same folder of classes.dex)

dex2jar.bat  classes.dex   (for winfows)
dex2jar.sh  classes.dex   (for linux)

This will produce an improbably named classes.dex.dex2jar.jar file.

Launch JD decompiler.

Open the classes.dex.dex2jar.jar file and then view the .class files

Qt on Android : How to reset Inactivity Time

Publish the new topic about "how to rest Inactivity Time" for Android form QT

Here the java class called by JNI

1. //
2. // Next72Utility.java
3. //
4. package org.qtproject.example.Chronometer;
5.  
6. import android.content.Context;
7. import android.app.Activity;
8. import android.view.WindowManager;
9. import android.view.WindowManager.LayoutParams;
10. import android.os.Bundle;
11.  
12. public class Next72Utility extends org.qtproject.qt5.android.bindings.QtActivity
13. {
14.  
15.    public static Next72Utility m_istance;
16.  
17.  
18.    public Next72Utility()
19.    {
20.        m_istance = this;
21.    }
22.  
23.  
24.    public void onCreate(Bundle savedInstanceState)
25.    {
26.        super.onCreate(savedInstanceState);
27.        getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
28.                                         WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
29.    }
30.  
31. }

Here the link to post

Qt on Android : How to Vibrate the device

Publish the new topic about: "How to Vibrate the device" at following link

List below steps for all developers.

The Correct Size Of Splash Screen for Anforid

LDPI:
    Portrait: 200x320px
    Landscape: 320x200px
MDPI:
    Portrait: 320x480px
    Landscape: 480x320px
HDPI:
    Portrait: 480x800px
    Landscape: 800x480px
XHDPI:
    Portrait: 720px1280px
    Landscape: 1280x720px

What's the correct size icon for drawable

When you build your app in Android, you must respect the following icon size:

drawable-ldpi           120dpi                36px x   36px
drawable-mdpi         160dpi      1x       48px x   48px 
drawable-hdpi          240dpi     1.5x     72px x   72px
drawable-xhdpi        320dpi      2         96px x   96px
drawable-xxhdpi 480dpi      3x      144px x 144px
drawable-xxxhdpi 640dpi      4x      192px x 192px

Build and deploy Qt apps to Android using Qt 5.1 on Windows