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tk(attribtable) tk(attribtable) 





NAME


attribtable - Create an attribute table, used to query and modify
    arbitrary data attached to any widget.






SYNOPSIS


tk attribtable tableName








DESCRIPTION


This command creates an attribute table of the name
    tableName, implemented as a hash table and accessible as a command in
    the namespace of the calling context if not fully qualified, and returns the
    fully qualified name of the command just created.


An attribute table is used to query and modify arbitrary data
    attached to any widget. These data are commonly called
  attributes.


If an attribute table of the given name already exists then it is
    replaced with the new one and all the attributes of all widgets set using
    the old table instance will be unset.


REMARK 1: When the tableName command is deleted (via
    rename tableName "" or by deleting the containing
    namespace), all the attributes of all widgets set using this command are
    automatically unset and the underlying hash table is deleted. This will free
    all the memory used by the table.


REMARK 2: When a widget is destroyed, all of its attributes
    set by all attribute table commands are automatically unset. This will free
    all the memory used by the widget's attributes.


The command tableName created by this command has the
    signature






tableName set|get|unset|clear|exists|names|pathnames args




In the description of the supported forms below, pathName
    specifies a widget whose attributes are being queried or modified via the
    tableName command.



  

  
Sets (i.e., adds or updates) the attributes identified by the name
      arguments to the values given by the value arguments. Returns an
      empty string. Example:










# Save and then change the button's text
tk attribtable table
table set .btn prevText [.btn cget -text]
.btn configure -text "NewText"







  

  
If name is specified then returns the corresponding attribute
      value, or an empty string or defaultValue (if given) if no
      corresponding value exists. Otherwise returns a list consisting of all
      attribute names and values of the widget pathName. Example:










# Restore the button's previous text
.btn configure -text [table get .btn prevText]







  

  
Unsets the attributes identified by the name arguments. Returns an
      empty string. Example:










table unset .btn prevText







  

  
Unsets all attributes and removes pathName from the list of those
      widgets that have attributes set via tableName set. Returns
      an empty string. Example:










table clear .btn







  

  
If the optional argument is present then returns 1 if the attribute
      identified by name exists and 0 otherwise. Without the
      optional argument the return value is 1 if the widget
      pathName has at least one attribute set via tableName
      set and 0 otherwise. Example:










if [table exists .btn prevText] {


    # Restore the button's previous text


    .btn configure -text [table get .btn prevText]
}







  

  
Returns a list consisting of all attribute names of the widget
      pathName. Example:










puts "attribute names for .btn: [table names .btn]"







  

  
Returns a list consisting of the path names of all widgets that have
      attributes set via tableName set. Example:










puts "widgets in table: [table pathnames]"










KEYWORDS


widget, attribute, attribute table







  

    n
    9.1