Object subclass: #Visualizer
        instanceVariableNames: 'data bars '
        classVariableNames: ''
        poolDictionaries: ''
        category: 'Visualizer'!


!Visualizer methodsFor: 'showing'!

show
        | gc numberOfBars max|
      numberOfBars := bars size.
        gc := (ExamplesBrowser prepareScratchWindowOfSize: 500 @ 200 ) 
              graphicsContext.
        max := bars first height.
        bars do: [:aBar | (max < (aBar height)) ifTrue: [max := aBar height]].
      bars do: [:aBar | aBar showAt: gc withSize: (500/numberOfBars)@200 highest:max]! !

!Visualizer methodsFor: 'initialization'!

data: aDictionary 
        "connect this visualizer to a dictionary"

        data := aDictionary.
      bars := OrderedCollection new.!

forHeight: anItem

     | collection aBar i|

      collection := data at: anItem.
        i := 0.
      collection do: [:aValue | 
                                        aBar := Bar new.
                                        aBar height: aValue.
                                        aBar index: i.
                                        bars add: aBar.
                                        i := i+1].! !
"-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- "!

Visualizer class
        instanceVariableNames: ''!


!Visualizer class methodsFor: 'demo'!

demo
        | cities v |
        cities := Dictionary new.
        cities at: #names put: #(#Atlanta #Detroit #MexicoCity #Oz #NYC).
        cities at: #populations put: #(100000 1000000 10000000 10.78 3000000).
        cities at: #avetemp put: #(72 61 91 13 65).
        cities at: #meanness put: #(4 7 5 2 6).
        
        v := Visualizer new data: cities.       "Opens up the Visualization window --just a Graphics pane."
        v forHeight: #avetemp.
        v show! !

Object subclass: #Bar
        instanceVariableNames: 'height index '
        classVariableNames: ''
        poolDictionaries: ''
        category: 'Visualizer'!


!Bar methodsFor: 'showing'!

showAt: gc withSize: size highest: max 
        | aBarShape x y |
        aBarShape := OrderedCollection new.
        x := size x.
        y := size y * 4 / 5.
        aBarShape add: x / 4 @ (y - (height * y * 3 / (max * 4))); 
                        add: x * 3 / 4 @ (y - (height * y * 3 / (max * 4))); 
                        add: x * 3 / 4 @ y; 
                        add: x / 4 @ y.
        gc displayPolygon: aBarShape at: index * x @ 0! !

!Bar methodsFor: 'accessing'!

height 
        ^height!

height: aValue 
        height := aValue!

index: anIndex 
        index := anIndex! !