Introduction to QtGUI HistorySlide 3Slide 4Slide 5Apple gets a GUISlide 7Unix Gets a GUIMicrosoft Gets a GUIShellsWindows TimelineThe Qt StoryWhy GUI Toolkits?Why Cross-Platform GUI toolkitsStategies for Implementing Cross-Platform GUIsSlide 16Slide 17Qt AssistantA Simple Example /* HelloWorld.cpp */Line-by-lineSlide 21Callback FunctionSlide 23Event HandlingSignals and SlotsSignals and Slots (cont)Signals and Slots(cont)Slide 28qmakeDefining Signals and SlotsEventsWidgetsQt, a GUI toolkitOther Features of QtAcknowledgementsDale RobertsIntroduction to QtIntroduction to QtDale Roberts, LecturerComputer Science, IUPUIE-mail: [email protected] of Computer and Information Science,School of Science, IUPUIDale RobertsGUI HistoryGUI HistoryIn 1962, Douglas Engelbart In 1962, Douglas Engelbart invented the first “mouse,” invented the first “mouse,” which he called an “X-Y which he called an “X-Y Position Indicator.”Position Indicator.”It was a little gizmo housed in It was a little gizmo housed in a wooden box on wheels that a wooden box on wheels that moved around the desktop and moved around the desktop and took the cursor with it on the took the cursor with it on the display. display. Source: US Patent OfficeDale RobertsGUI HistoryGUI HistoryIn 1963 a grad student at In 1963 a grad student at MIT, Ivan Sutherland, MIT, Ivan Sutherland, submitted as his thesis a submitted as his thesis a program called program called “Sketchpad.” This was “Sketchpad.” This was the first GUI (Graphical the first GUI (Graphical User Interface) long User Interface) long before the term was before the term was coined." coined." http://accad.osu.edu/~waynec/history/images/ivan-sutherland.jpgDale RobertsGUI HistoryGUI HistoryIn the 1970s, at Xerox’s In the 1970s, at Xerox’s PARC facility, Alan Keys PARC facility, Alan Keys created an object-created an object-oriented graphical oriented graphical programming language programming language called “Smalltalk.” called “Smalltalk.” Smalltalk featured a Smalltalk featured a graphical user interface graphical user interface (GUI) that looked (GUI) that looked suspiciously similar to suspiciously similar to later iterations from both later iterations from both Apple and Microsoft. Apple and Microsoft. http://www.sra.co.jp/people/aoki/SqueakIdioms/chapter01/Xerox1100SIP.jpgDale RobertsGUI HistoryGUI History1981, Xerox attempted to 1981, Xerox attempted to market the “Star.” It market the “Star.” It introduced the idea of what introduced the idea of what you see is what you get you see is what you get (WYSIWYG). (WYSIWYG). Commercial failureCommercial failurecost ($15,000); cost ($15,000); IBM had just announced a less IBM had just announced a less expensive machineexpensive machinelimited functionalitylimited functionalitye.g., no spreadsheete.g., no spreadsheetclosed architecture, closed architecture, 3rd party vendors could not add 3rd party vendors could not add applicationsapplicationsperceived as slow perceived as slow but really fast!but really fast!slavish adherence to direct slavish adherence to direct manipulationmanipulationhttp://www.catb.org/~esr/writings/taouu/html/graphics/xerox_star.jpgDale RobertsApple gets a GUIApple gets a GUIIn 1983, the Apple Lisa In 1983, the Apple Lisa was first GUI offering.was first GUI offering.http://fp3.antelecom.net/gcifu/applemuseum/lisa2.htmlhttp://www.s-line.de/homepages/horber-privat/bilder/apple2a.jpgApple II, 1980LisaDale RobertsApple gets a GUIApple gets a GUIIn 1984, Macintosh was the first In 1984, Macintosh was the first computer with a GUI marketed to computer with a GUI marketed to the masses.the masses.““old ideas” but well done! old ideas” but well done! Commercial success because:Commercial success because:aggressive pricing ($2500)aggressive pricing ($2500)did not need to trail blaze did not need to trail blaze learned from mistakes of Lisa and learned from mistakes of Lisa and corrected them; ideas now “mature”corrected them; ideas now “mature”market now ready for themmarket now ready for themdeveloper’s toolkit encouraged 3rd developer’s toolkit encouraged 3rd party non-Apple software party non-Apple software interface guidelines encouraged interface guidelines encouraged consistency between applicationsconsistency between applicationsdomination in desktop publishing domination in desktop publishing because of affordable laser printer because of affordable laser printer and excellent graphicsand excellent graphicsFull Microsoft Office suiteFull Microsoft Office suite(Apple was the dominant player at (Apple was the dominant player at this time.)this time.)http://computermuseum.50megs.com/images/collection/apple-mac-plus.jpghttp://toastytech.com/guis/bigmac1.gifDale RobertsUnix Gets a GUIUnix Gets a GUIThe X Windows System was The X Windows System was introduced in the mid-1980s to introduced in the mid-1980s to provide graphical support for provide graphical support for unix operating systems.unix operating systems.The implementation was a The implementation was a client-server approach, where client-server approach, where an X window system server an X window system server ran on the displaying machine, ran on the displaying machine, and the client programs and the client programs communicated with it using a communicated with it using a network protocol.network protocol.X provides only a X provides only a communication communication mechanism, mechanism, not policynot policy. At least three major . At least three major user interface look & feel user interface look & feel styles are widely used on X - styles are widely used on X - MIT's own Athena style, Sun MIT's own Athena style, Sun and AT&T's OpenLook, and and AT&T's OpenLook, and OSF's Motif (supported OSF's Motif (supported primarily by HP and IBM). primarily by HP and IBM). http://www.pattosoft.com.au/jason/Articles/HistoryOfComputers/X11.gifDale RobertsMicrosoft Gets a GUIMicrosoft Gets a GUIMicrosoft introduced Microsoft introduced Windows 1.0 in 1985Windows 1.0 in 1985Tiled Windows, no Tiled Windows, no overlappingoverlappingWindows 2.03 in 1987Windows 2.03 in 1987Overlapping windowsOverlapping windowsWindows 3.0 in 1990Windows 3.0 in 1990Features Program ManagerFeatures Program ManagerDale RobertsShellsShellsUnix and DOS operating systems circa 1980s do support Unix and DOS operating systems circa 1980s do support text-based user interfaces via a program called a