How to create a standalone app with Glamorous Toolkit

Creating a standalone app based on Glamorous Toolkit is as simple as opening an application specific window and closing the existing GT window. This can be achieved in just a few steps.

Open a space with a scene

		
			BlSpace
			
				Object subclass: #BlSpace
	uses: TBlEventTarget + TBlSpaceProperties + TBlDebug
	instanceVariableNames: 'id host hostSpace extent position root resizable borderless dirtyAreas eventDispatcher eventListener eventRecorder mouseProcessor focusProcessor keyboardProcessor focusChain dragboard nextPulseRequested currentCursor session focused title fullscreen fullsize layoutError tasks time touchProcessor frame gestureProcessor elementsNeedingPaint elementsNeedingLayout telemetry reference elementsNeedingStyle elementsNeedingPropertiesComputation iconStencil'
	classVariableNames: 'UniqueIdGenerator'
	package: 'Bloc-Space'

is responsible for displaying a scene in a separate window. Users can customise window's title or extent. To spawn a window send

		
			BlSpace>>#show
			
				show
	"Open me in a window and show it to the user"

	"delegate showing work to the Universe"	
	(BlParallelUniverse forHost: self host class) openSpace: self

to an instance of the space.

			
| aContainer aSpace | 
aContainer := BrVerticalPane new
		matchParent;
		alignCenter.
aContainer addChild: (BrLabel new
		look: (BrGlamorousLabelLook new fontSize: 100; bold);
		text: 'Hello world!').
		
aSpace := BlSpace new
		addChild: aContainer;
		extent: 800@600;
		title: 'Hello World'.

aSpace show.
]

Clean up existing windows

Glamorous Toolkit comes with a

		
			GtWorld
			
				BlSpace subclass: #GtWorld
	instanceVariableNames: 'worldElement'
	classVariableNames: ''
	package: 'GToolkit-World-UI'

opened by default. When creating a standalone app based on GT we should close that window, which can be done in two steps.

Disable shutdown-on-close listener

To shutdown the process when a window is closed, we add a

		
			BlSpaceShutdownOnCloseListener
			
				BlBasicEventHandler subclass: #BlSpaceShutdownOnCloseListener
	instanceVariableNames: 'shouldSave'
	classVariableNames: ''
	package: 'Bloc-Space - Events'

as an event handler to a

		
			BlSpace
			
				Object subclass: #BlSpace
	uses: TBlEventTarget + TBlSpaceProperties + TBlDebug
	instanceVariableNames: 'id host hostSpace extent position root resizable borderless dirtyAreas eventDispatcher eventListener eventRecorder mouseProcessor focusProcessor keyboardProcessor focusChain dragboard nextPulseRequested currentCursor session focused title fullscreen fullsize layoutError tasks time touchProcessor frame gestureProcessor elementsNeedingPaint elementsNeedingLayout telemetry reference elementsNeedingStyle elementsNeedingPropertiesComputation iconStencil'
	classVariableNames: 'UniqueIdGenerator'
	package: 'Bloc-Space'

. It should be removed before we close such spaces.

			
GtWorld allInstances do: [ :eachWorld | eachWorld removeShutdownListener ]
]

Closing an existing GtWorld

To close an opened window, it is enough to just send

		
			BlSpace>>#close
			
				close
	"Delegate closing work to the Universe"
	
	(BlParallelUniverse forHost: self host class) closeSpace: self

to the associated space.

			
GtWorld allInstances do: [ :eachWorld | eachWorld close ]
]

Save the image

Once the intended application window is opened and there are no more GT windows we can save the image (without quitting):

			
Smalltalk snapshot: true andQuit: false
]