This document discusses building Ring games for Android using Ring Game Engine and SDL. It covers downloading requirements like the Android SDK and NDK, setting up the project folder to add source code and assets, and building the project using Ant to create an APK file. It also discusses creating desktop and mobile applications using Qt classes in Ring for GUI development. Examples are provided for basic GUI apps, using layouts, QTextEdit, and QListWidget widgets.

1. CHAPTER
FORTYSIX
BUILDING GAMES FOR ANDROID
In this chapter we will learn about Building RingLibSDL Games for Mobile.
So we can create packages (*.apk) for the applications that are developed using Ring Game Engine for 2D Games.
46.1 Download Requirements and Update the Android SDK
• 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
• Update the Android SDK to get the API and tools packages required for development
46.2 Project Folder
Open the project folder : ring/android/ringlibsdl/project
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You can add the source code (*.ring) and Images/Sound Files to the assets folder.
You will find the Flappy Bird 3000 Game ready for building.
The execution starts from the start.ring file
load "game2.ring"
46.3 Building the project
Move to the ring/android/ringlibsdl/project folder
We can build using the next command (We need to do this for one time only).
ndk-build
Then we can create the package (*.apk) using the next command.
46.3. Building the project 381

3. Ring Documentation, Release 1.2
ant debug
46.3. Building the project 382

4. CHAPTER
FORTYSEVEN
DESKTOP AND MOBILE DEVELOPMENT USING RINGQT
In this chapter we will learn how to use the Qt framework classes in our Ring applications to create Desktop and
Mobile Applications.
47.1 The First GUI Application
In this example we will create an application to ask the user about his/her name. When the user type the name in the
textbox then click on “Say Hello” button, the textbox value will be updated by adding “Hello ” to the name.
Load "guilib.ring"
MyApp = New qApp {
win1 = new qWidget() {
setwindowtitle("Hello World")
setGeometry(100,100,370,250)
label1 = new qLabel(win1) {
settext("What is your name ?")
setGeometry(10,20,350,30)
setalignment(Qt_AlignHCenter)
}
btn1 = new qpushbutton(win1) {
setGeometry(10,200,100,30)
settext("Say Hello")
setclickevent("pHello()")
}
btn1 = new qpushbutton(win1) {
setGeometry(150,200,100,30)
settext("Close")
setclickevent("pClose()")
}
lineedit1 = new qlineedit(win1) {
setGeometry(10,100,350,30)
}
show()
}
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exec()
}
Func pHello
lineedit1.settext( "Hello " + lineedit1.text())
Func pClose
MyApp.quit()
Program Output:
At first we type the name in the textbox
Then we click on the say hello button
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47.2 Using Layout
The next example is just an upgrade to the previous application to use the vertical layout.
Load "guilib.ring"
MyApp = New qApp {
win1 = new qWidget() {
setwindowtitle("Hello World")
setGeometry(100,100,400,130)
label1 = new qLabel(win1) {
settext("What is your name ?")
setGeometry(10,20,350,30)
setalignment(Qt_AlignHCenter)
}
btn1 = new qpushbutton(win1) {
setGeometry(10,200,100,30)
settext("Say Hello")
setclickevent("pHello()")
}
btn2 = new qpushbutton(win1) {
setGeometry(150,200,100,30)
settext("Close")
setclickevent("pClose()")
}
lineedit1 = new qlineedit(win1) {
setGeometry(10,100,350,30)
}
layout1 = new qVBoxLayout() {
addwidget(label1)
addwidget(lineedit1)
addwidget(btn1)
addwidget(btn2)
}
win1.setlayout(layout1)
show()
}
exec()
}
Func pHello
lineedit1.settext( "Hello " + lineedit1.text())
Func pClose
MyApp.quit()
The application during the runtime!
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47.3 Using the QTextEdit Class
In this example we will use the QTextEdit Class
Load "guilib.ring"
New qApp {
win1 = new qWidget() {
setwindowtitle("QTextEdit Class")
setGeometry(100,100,500,500)
new qtextedit(win1) {
setGeometry(10,10,480,480)
}
show()
}
exec()
}
During the runtime we can paste rich text in the qtextedit widget
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47.4 Using the QListWidget Class
In this example we will use the QListWidget Class
Load "guilib.ring"
New qApp {
win1 = new qWidget() {
setGeometry(100,100,400,400)
list1 = new qlistwidget(win1) {
setGeometry(150,100,200,200)
alist = ["one","two","three","four","five"]
for x in alist additem(x) next
setcurrentrow(3,2)
win1.setwindowtitle("Items Count : " + count() )
}
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btn1 = new qpushbutton(win1) {
setGeometry(10,200,100,30)
settext("selected item")
setclickevent("pWork()")
}
btn2 = new qpushbutton(win1) {
setGeometry(10,240,100,30)
settext("Delete item")
setclickevent("pWork2()")
}
show()
}
exec()
}
func pWork
btn1.settext(string(list1.currentrow()))
func pWork2
list1 {
takeitem(currentrow())
}
The application during the runtime
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Another Example:
Load "guilib.ring"
New qApp {
win1 = new qWidget() {
setGeometry(100,100,500,400)
list1 = new qlistwidget(win1) {
setGeometry(150,100,200,200)
alist = ["one","two","three","four","five"]
for x in alist additem(x) next
setcurrentrow(3,2)
win1.setwindowtitle("Items Count : " + count() )
}
btn1 = new qpushbutton(win1) {
setGeometry(10,200,100,30)
settext("selected item")
setclickevent("pWork()")
}
btn2 = new qpushbutton(win1) {
setGeometry(10,240,100,30)
settext("Delete item")
setclickevent("pWork2()")
}
show()
}
exec()
}
func pWork
nbrOfItems = list1.count()
curItemNbr = list1.currentrow()
curValue = list1.item(list1.currentrow()).text()
win1.setwindowtitle( "After Select - NbrOfItems: " + nbrOfItems +
" CurItemNbr: " + curItemNbr + " CurValue: " + curValue )
btn1.settext( string(list1.currentrow() ) + " --- " +
list1.item(list1.currentrow()).text() )
func pWork2
list1 {
takeitem(currentrow())
nbrOfItems = count()
curItemNbr = currentrow()
curValue = item(currentrow()).text()
47.4. Using the QListWidget Class 389