This document provides code examples for developing a simple notepad application using RingQt. It defines global variables to store the active file name, text and background colors, font, and a website URL. It then shows how to create the main window with menus to open, save, and exit files, as well as options to change colors and font.
The Ring programming language version 1.10 book - Part 79 of 212
1. Ring Documentation, Release 1.10
65.51 Change Focus
The next example change the focus using the ENTER key.
load "guilib.ring"
new qApp {
win = new qWidget() {
resize(600,600)
SetWindowTitle("Change Focus")
text1 = new qLineEdit(win)
text2 = new qLineEdit(win)
text3 = new qLineEdit(win)
text4 = new qLineEdit(win)
layout1 = new qVBoxLayout() {
AddWidget(text1)
AddWidget(text2)
AddWidget(text3)
AddWidget(text4)
}
setLayout(Layout1)
65.51. Change Focus 748
2. Ring Documentation, Release 1.10
aList = [text1,text2,text3,text4]
oFilter = new qallevents(win)
oFilter.setKeyPressEvent("pWork()")
installeventfilter(oFilter)
show()
}
exec()
}
func pWork
nCode = oFilter.getkeycode()
if nCode = 16777220 # ENTER Key
for x=1 to len(aList)
if aList[x].HasFocus()
t = x+1
if t > len(aList) t=1 ok
aList[t].SetFocus(0)
exit
ok
next
ok
65.52 Regular Expressions
The next example uses the Regular Expressions classes.
load "guilib.ring"
new qApp
{
see "Using Regular Expressions" + nl
exp = new qregularexpression() {
setPattern("dd w+")
see pattern() + nl
match = match("33 one",0,0,0)
see match.hasmatch() + nl
match = match("3 one",0,0,0)
see match.hasmatch() + nl
match = match("welcome 11 one",0,0,0)
see match.hasmatch() + nl
matched = match.captured(0)
see matched + nl
}
exp = new qregularexpression() {
setPattern("^(dd)/(dd)/(dddd)$")
see pattern() + nl
match = match("08/12/1985",0,0,0)
see match.hasmatch() + nl
day = match.captured(1)
month = match.captured(2)
year = match.captured(3)
see day + nl + month + nl + year + nl
see "(" + match.capturedStart(1) + "," + match.capturedEnd(1)+ ")" + nl
see "(" + match.capturedStart(2) + "," + match.capturedEnd(2)+ ")" + nl
see "(" + match.capturedStart(3) + "," + match.capturedEnd(3)+ ")" + nl
65.52. Regular Expressions 749
3. Ring Documentation, Release 1.10
}
}
Output
Using Regular Expressions
dd w+
1
0
1
11 one
^(dd)/(dd)/(dddd)$
1
08
12
1985
(0,2)
(3,5)
(6,10)
65.53 Simple Client and Server Example
In this section we will learn about creating simple Client and Server Application
Load "guilib.ring"
new qApp {
oClient = new Client { client() }
oServer = new Server { server() }
exec()
}
Class Client
win1 lineedit1 cOutput=""
oTcpSocket
func client
win1 = new qwidget()
new qpushbutton(win1) {
setgeometry(50,50,100,30)
settext("connect")
setclickevent("oClient.Connect()")
}
lineedit1 = new qtextedit(win1) {
setGeometry(150,50,200,300)
}
win1 {
setwindowtitle("client")
setgeometry(10,100,400,400)
show()
65.53. Simple Client and Server Example 750
4. Ring Documentation, Release 1.10
}
func connect
cOutput = "Connect to host 127.0.0.1 port 9999" + nl
lineedit1.settext(cOutput)
oTcpSocket = new qTcpSocket(win1) {
setconnectedevent("oClient.pConnected()")
setreadyreadevent("oClient.pRead()")
connecttohost("127.0.0.1",9999,3,0)
waitforconnected(5000)
}
func pConnected
cOutput += "Connected!" + nl
lineedit1.settext(cOutput)
func pRead
cOutput += "Ready Read!" + nl
lineedit1.settext(cOutput)
cOutput += oTcpSocket.readall().data() + nl
lineedit1.settext(cOutput)
Class Server
win1 lineedit1
oTcpServer oTcpClient
cOutput = ""
func server
win1 = new qwidget()
lineedit1 = new qtextedit(win1) {
setGeometry(150,50,200,300)
}
win1 {
setwindowtitle("Server")
setgeometry(450,100,400,400)
show()
}
oTcpServer = new qTcpServer(win1) {
setNewConnectionEvent("oServer.pNewConnection()")
oHostAddress = new qHostAddress()
oHostAddress.SetAddress("127.0.0.1")
listen(oHostAddress,9999)
}
cOutput = "Server Started" + nl +
"listen to port 9999" + nl
lineedit1.settext(cOutput)
Func pNewConnection
oTcpClient = oTcpServer.nextPendingConnection()
65.53. Simple Client and Server Example 751
5. Ring Documentation, Release 1.10
cOutput += "Accept Connection" + nl
lineedit1.settext(cOutput)
oTcpClient {
cStr ="Hello from server to client!"+char(13)+char(10)
write(cStr,len(cStr))
flush()
waitforbyteswritten(300000)
close()
}
The application during the runtime
65.54 Dynamic Objects
We may create objects in the runtime and add them to windows.
Example:
load "guilib.ring"
oFormDesigner = new FormDesigner { start("oFormDesigner") }
Class FormDesigner
winToolBox winForm
aObjects = []
func start cObjectName
oApp = new qApp
winToolBox = new qWidget()
winToolBox.setWindowTitle("ToolBox")
65.54. Dynamic Objects 752
6. Ring Documentation, Release 1.10
winToolBox.move(10,10)
winToolBox.resize(300,600)
btn = new qPushButton(winToolBox)
btn.resize(300,30)
btn.setText("Create Button")
btn.setClickEvent(cObjectName+".pCreateButton()")
btn.show()
winToolBox.show()
winForm = new qWidget() {
move(400,50)
setWindowTitle("Form Designer")
resize(600,600)
show()
}
oApp.exec()
func pCreateButton
nCount = len(aObjects)
aObjects + new MyButton(winForm)
{
nIndex = nCount + 1
setText("Button"+ nIndex)
Move(30*nIndex,30*nIndex)
resize(100,30)
show()
}
Class MyButton from qPushButton
nIndex = 0
65.55 Weight History Application
The next sample help in recording (Date, Time and Weight).
Load "guilib.ring"
MyApp = new qApp
{
$ApplicationObject = "oApp" # To be used when calling events
oApp = new App
exec()
oApp.CloseDatabase()
}
class App
cDir = currentdir() + "/"
oCon
65.55. Weight History Application 753
7. Ring Documentation, Release 1.10
aIDs = []
win1 = new qWidget()
{
setWindowTitle("Weight History")
resize(600,600)
layoutButtons = new qhboxlayout()
{
label1 = new qLabel(win1) { setText("Weight") }
text1 = new qlineedit(win1)
btnAdd = new qpushbutton(win1) {
setText("Add")
setClickEvent($ApplicationObject+".AddWeight()")
}
btnDelete = new qpushbutton(win1) {
setText("Delete")
setClickEvent($ApplicationObject+".Deleteweight()")
}
addwidget(label1)
addwidget(text1)
addwidget(btnAdd)
addwidget(btnDelete)
}
layoutData = new qhboxlayout()
{
Table1 = new qTableWidget(win1) {
setrowcount(0)
setcolumncount(3)
setselectionbehavior(QAbstractItemView_SelectRows)
setHorizontalHeaderItem(0, new QTableWidgetItem("Date"))
setHorizontalHeaderItem(1, new QTableWidgetItem("Time"))
setHorizontalHeaderItem(2, new QTableWidgetItem("Weight"))
setitemChangedEvent($ApplicationObject+".ItemChanged()")
setAlternatingRowColors(true)
horizontalHeader().setStyleSheet("color: blue")
verticalHeader().setStyleSheet("color: red")
}
addWidget(Table1)
}
layoutClose = new qhboxlayout()
{
btnclose = new qpushbutton(win1) {
setText("Close")
setClickEvent("MyApp.Quit()")
}
addwidget(btnClose)
}
layoutMain = new qvboxlayout()
{
addlayout(layoutButtons)
addLayout(LayoutData)
addLayout(layoutClose)
}
setlayout(layoutMain)
self.OpenDatabase()
self.ShowRecords()
show()
}
65.55. Weight History Application 754
8. Ring Documentation, Release 1.10
Func OpenDatabase
lCreate = False
if not fexists(cDir + "weighthistory.db")
lCreate = True
ok
new QSqlDatabase() {
this.oCon = addDatabase("QSQLITE") {
setDatabaseName("weighthistory.db")
Open()
}
}
if lCreate
new QSqlQuery( ) {
exec("create table weighthistory (id integer primary key,"+
" f_date varchar(10),"+
" f_time varchar(8), f_weight varchar(8) );")
delete()
}
ok
Func CloseDatabase
oCon.Close()
Func AddWeight
cWeight = text1.text()
AddRecord(cWeight)
Func DeleteWeight
Table1 {
nRow = CurrentRow()
if nRow >= 0
nID = this.aIDs[nROW+1]
new QSqlQuery( ) {
exec("delete from weighthistory where id = " + nID )
}
Del(this.aIDs,nRow+1)
removerow(nRow)
selectrow(nRow)
ok
}
Func AddRecord cWeight
new QSqlQuery( ) {
cStr = "insert into weighthistory (f_date,f_time,f_weight) values"+
" ('%f1','%f2','%f3')"
cDate = Date()
cTime = Time()
cStr = substr(cStr,"%f1",cDate)
cStr = substr(cStr,"%f2",cTime)
cStr = substr(cStr,"%f3",cWeight)
exec(cStr)
delete()
}
ShowRecords()
Table1.selectrow(table1.rowcount()-1)
65.55. Weight History Application 755
9. Ring Documentation, Release 1.10
Func ShowRecords
table1.setitemChangedEvent("")
aIDs = []
query = new QSqlQuery() {
exec("select * from weighthistory")
nRows = 0
this.Table1.setrowcount(0)
while movenext()
this.table1 {
insertRow(nRows)
this.aIDs + query.value(0).tostring()
for x = 1 to 3
cStr = query.value(x).tostring()
item = new qTableWidgetItem(cStr)
setItem(nRows,x-1,item)
next
}
nRows++
end
delete()
}
table1.setitemChangedEvent($ApplicationObject+".ItemChanged()")
Func ItemChanged
nRow = table1.currentrow()
if nRow >= 0
myitem = Table1.item(table1.currentrow(),0)
cDate = myitem.text()
myitem = Table1.item(table1.currentrow(),1)
cTime = myitem.text()
myitem = Table1.item(table1.currentrow(),2)
cWeight = myitem.text()
new QSqlQuery( ) {
cStr = "update weighthistory set f_date ='%f1' , f_time = '%f2' , "+
"f_weight ='%f3' where id = " + this.aIDs[nROW+1]
cStr = substr(cStr,"%f1",cDate)
cStr = substr(cStr,"%f2",cTime)
cStr = substr(cStr,"%f3",cWeight)
exec(cStr)
delete()
}
ok
The next screen shot for the application during the runtime
65.55. Weight History Application 756
10. Ring Documentation, Release 1.10
65.56 Notepad Application
In the next example we will see simple Notepad developed using the RingQt
Load "guilib.ring"
cActiveFileName = ""
aTextColor = [0,0,0]
aBackColor = [255,255,255]
cFont = "MS Shell Dlg 2,14,-1,5,50,0,0,0,0,0"
cWebsite = "http://www.google.com"
65.56. Notepad Application 757