 
 subsubsection3_8_5_1.html  section3_8.html  subsubsection3_8_4_5.html  tableofcontents3_1.html   Next: subsubsection3_8_5_1.html Initialization of Public Up: section3_8.html Tix Object Oriented  Previous: subsubsection3_8_4_5.html The SetBindings Method    Declaring and Using Variables  
The private variables of a widget class do not need to be
  declared. In fact they can be initialized and used anywhere by any
  method. Usually, however, general purpose private variables are
  initialized by the 
InitWidgetRec method and subwidget
  variables are initialized in the 
ConstructWidget method.
We have seen in the tixArrowButton:InitWidgetRec example that
  the private variable 
data(count) was initialized there. Also,
  the private variable 
data(w:button) was initialized in tixArrowButton:ConstructWidget and subsequently used in tixArrowButton:SetBindings.
In contrast, public variables must be declared inside the class
  declaration. The following arguments are used to declare the public
  variables and specify various options for them:
 -flag: As shown in the class declaration in figure
  6-2, the 
-flag argument declares all the public
  variables of the TixArrowButton class, 
-direction and -state-configspec: We can use the -configspec argument to
  specify the details of each public variable. For example, the
  following declaration
  -configspec {    {-direction direction Direction e}
    {-state state State normal}
}
specifies that the -direction variable has the resource
  name 
direction and resource class Direction; its default
  value is 
e. The application programmer can assign value to
  this variable by using the 
-direction option in the command
  line or by specifying resources in the Tk option database with its
  resource name or class. The declaration of 
-state installs
  similar definitions for that variable.
-alias: The -alias argument is used to specify
  alternative names for public variables. In our example, the setting
  -alias {    {-dir -direction}
}
specifies that -dir is the same variable as -direction. Therefore, when the application issue the command
  .up config -dir w
it is the same as issuing
  .up config -direction w
   The 
-alias option provides only an alternative name for
  the application programmer. Inside the widget's implementation code,
  the variable is still accessed as 
data(-direction), not  
data(-dir).  
 
 subsubsection3_8_5_1.html#SECTION00085100000000000000 Initialization of Public Variables   subsubsectionstar3_8_5_2.html#SECTION00085200000000000000  Type Checker   subsubsection3_8_5_3.html#SECTION00085300000000000000 Public Variable Configuration Methods   subsubsectionstar3_8_5_4.html#SECTION00085400000000000000  Configuration Methods and Public Variable Initialization  http://tix.sourceforge.nethttp://tix.sourceforge.net 