ImageChoiceBox

AboutToHide AboutToShow CalcBoundsBox CalcInsidePart Draw DrawControlMechanism FilterChoices Notice TextFromValue UpdateChoices

Attributes

Choices EmptyMessage Filter Image Level

Fields

instance ImageChoiceBox tag;
 relativeOrigin: <0.0,0.0>;
    contentSize: <0.0,0.0>;
      viewFlags: 0x00000000;
     labelStyle: nilObject;
          color: 0;
       altColor: 0;
         shadow: nilObject;
          sound: nilObject;
         border: nilObject;
          image: nilObject;
      textStyle: nilObject;
   controlFlags: 0;
          level: 0;
            min: 0;
            max: 0;
         target: nilObject;
targetAttribute: nilOperation;
   upDownImages: nilObject;
        choices: nilObject;
lastOneEditable: false;
     resetValue: false;
transientChoices: false;
  choiceObjects: false;
    matchByName: false;
 useObjectIndex: false;
     choiceWrap: false;
 maxFromChoices: false;
useObjectAttribute: false;
matchWithSameChoice: false;
neverAdjustBoxSize: false;
   lookForGroup: false;
 destroyChoices: false;
    numericText: false;
hasOtherChoiceObject: false;
   emptyMessage: nilObject;
         source: nilObject;
sourceAttribute: nilOperation;
         filter: nilClass;
end instance;

Define Class ImageChoiceBox;
    inherits from ChoiceBox;
    
    field emptyMessage: Viewable, getter, setter;
        // used by EmptyMessage attribute
    field source: Object;
        // object that determines, along with sourceAttribute, choice list for choicebox
    field sourceAttribute: OperationNumber;
        // attribute number used to get choice list for choice box from source;
        // if zero, choice list for choice box is source object itself
    field filter: ClassNumber, getter, setter;      
        // used by Filter attribute
    
    attribute EmptyMessage: Viewable, safe;
        // a viewable (typically a text field) that is made visible and brought
        // to the front when choice list is empty (can be nilObject)
    attribute Filter: ClassNumber, safe;
        // a class number or 0;
        // if non-zero, FilterChoices weeds out all items that do not implement this class number
        // override occasionally to weed out items differently -- may override FilterChoices
        // or SetChoices (rarely) as well.

    operation FilterChoices(newChoices: ObjectList; filter: ClassNumber);
        // implements the behavior described under Filter (only called if Filter is non-zero)
        // called from SetChoices
        // override to do different filtering

    overrides AboutToHide;
        // stops observing source
    overrides AboutToShow;
        // synchs choice list with source object;
        // shows or hides empty message as appropriate;
        // begins observing source
    overrides CalcBoundsBox;
        // accounts for image bounds
    overrides CalcInsidePart;
        // uses part code returned by InsideImage if any;
        // otherwise delegates to Viewable_
    overrides Draw;
        // draws nothing at all if no choices;
        // does not draw control mechanism (left/right arrows) if only 1 choice;
        // draws image at center of choice box;
    overrides DrawControlMechanism;
        // delegates to Meter to draw the left/right arrow ends;
        // draws light gray background between ends
    overrides Image;
        // if item at current level in choice list is image, returns it;
        // otherwise returns Image() of item at current level in choice list
    overrides Notice;
        // synchs choice list with source object if source object changed
    overrides SetLevel;
        // handles bounds changing due to different image sizes;
    overrides SetChoices;
        // if Filter is non-zero, calls FilterChoices on the new choices
        // shows or hides empty message as appropriate
    overrides TextFromValue;
        // returns nilObject if value as integer is greater than count of choice list;
        // otherwise returns inherited value;
    overrides UpdateChoices;
        // shows or hides empty message as appropriate
end class;