.. index:: 
	single: Building RingQt Applications for Mobile; Introduction

=======================================
Building RingQt Applications for Mobile
=======================================

In this chapter we will learn about Building RingQt Applications for Mobile.


.. index:: 
	pair: Building RingQt Applications for Mobile; Download Requirements

Download Requirements
=====================

Check the next link : http://doc.qt.io/qt-5/androidgs.html

Download 

* The Android SDK Tools

	https://developer.android.com/studio/index.html

* The Android NDK 

		https://developer.android.com/ndk/index.html

* Apache Ant v1.8 or later 

		http://ant.apache.org/bindownload.cgi

* Java SE Development Kit (JDK) v6 or later

		http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html

.. index:: 
	pair: Building RingQt Applications for Mobile; Update the Android SDK

Update the Android SDK
======================

Update the Android SDK to get the API and tools packages required for development

.. index:: 
	pair: Building RingQt Applications for Mobile; Install Qt for Android

Install Qt for Android
======================

* You can install Qt for Android from the next link

		https://download.qt.io/archive/qt/5.5/5.5.1/

* Run Qt Creator, Select Tools > Options > Android to add the 
    Android NDK and SDK paths. 

		http://doc.qt.io/qtcreator/creator-developing-android.html

*  Using Qt Creator Open the project 

	Folder : ring/android/ringqt/project

	Project file : project.pro

* You will find the code in resources\test.ring

	You can modify the code then build and run for Desktop or Mobile.

.. image:: ringqtandroid_shot1.png
	:alt: RingQt for Android

.. index:: 
	pair: Building RingQt Applications for Mobile; Comments about developing for Android using RingQt

Comments about developing for Android using RingQt
==================================================

(1) The main project file is main.cpp 

	This file load Ring Compiler/Virtual Machine and RingQt 

	Then copy files during the runtime from the resources to temp. folder 

	Then run the test.ring

	Through main.cpp you can extract more files from the resources to temp. folder once you
	add them (create projects with many files).

(2) The next functions are missing from this Ring edition

	* Database (ODBC, SQLite & MySQL)

	* Security and Internet functions (LibCurl & OpenSSL)

	* RingAllegro (Allegro Library)

	* RingLibSDL (LibSDL Library)

	Just use Qt Classes through RingQt.

	For database access use the QSqlDatabase Class

.. note:: All of the missing libraries ((LibCurl, OpenSSL & Allegro) can be compiled for Android, but they are not included in this Qt project.

(3) use if isandroid() when you want to modify the code just for android

Example:

.. code-block:: ring

	if isandroid()
		// Android code
	else
  		// other platforms
	ok

(4) Sometimes you will find that the button text/image is repeated in drawing !
it's Qt problem that you can avoid using the next code.

.. code-block:: ring

	if isandroid()
		setStyleSheet("
			border-style: outset;
			border-width: 2px;
			border-radius: 4px;
			border-color: black;
			padding: 6px;")
	 ok

(5)  Always use Layouts instead of manual setting of controls position and size. 

This is the best way to get the expected user interface to avoid problems like (controls with small/extra size)

(6) When you deal with Qt Classes you can determine the images from resources (you don't need to copy them using main.cpp)


Example: 

.. code-block:: ring

	if isandroid()
	    mypic = new QPixmap(":/resources/cardsimage")
	else
	    mypic = new QPixmap("cards.jpg")
	ok

In the previous example, cards.jpg  is added to the resources then we write the "cardsimage" as alias for "cards.jpg"


