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Data entry example

With the widgets so far described, it is possible to make a small data entry example. It is not very sophisticated, and carries out no data validation, but illustrates the ease of creating a data entry screen.

The following personal data is to be collected:

Surname, First names, Address, Telephone number, Sex, Age

For the Surname, First names, Telephone number and Age, entry widgets will be used. For the Address, a text widget will be used, and for the Sex input, a radiobutton will be used.

The layout of the display will have a column of labels to the left, with a column of entry and other widgets to the right.

This can be implemented using two frames, one for each column.

Additionally, when all the data is entered, a Save button will store the data in a file, for future use, either by a TCL program, or by an external program, and a Quit button wll cause the program to finish.

#Define 2 frames - 1 to contain the columns, and 1 to contain the 
     #Save and Quit button.

     frame .fr1
     frame .fr2

     #Define two frames for the columns
     frame  .fr1.c1
     frame  .fr1.c2

     #define labels
     label .fr1.c1.lab1  -text "Surname"
     label .fr1.c1.lab2  -text "First Names"
     label .fr1.c1.lab3  -text "Address"
     label .fr1.c1.lab4  -text "Telephone Number"
     label .fr1.c1.lab5  -text "Sex"
     label .fr1.c1.lab6  -text "Age"

     #Now define the other widgets for the data
     entry .fr1.c2.surname1   -width 30 -relief sunken -textvariable surname
     entry .fr1.c2.firstname1 -width 30 -relief sunken  
                      -textvariable firstnames
     entry  .fr1.c2.address1   -width 30 -relief sunken  
                      -textvariable address
     entry .fr1.c2.telephone -width 20 -relief sunken -textvariable telno
     entry .fr1.c2.age1      -width 20 -relief sunken -textvariable age
     entry .fr1.c2.sex1      -width 20 -relief sunken -textvariable sex

     #We shall defer consideration of the use of radio buttons for
     #the next section, so we will simply allocate an entry widget for 
     #Sex for the moment.

     #Now define the buttons for saving and quitting
     button .fr2.button1 -text "Save" -command {savecommand}
     button .fr2.button2 -text "Quit" -command {exit}

     #Note: the command for save could be done by system
     #dependent commands, or by TCL commands.
     #For portability it is best to package them into a TCL procedure

     #Now pack all the widgets together - first within each frame
     #Column 1 widgets
     pack .fr1.c1.lab1 .fr1.c1.lab2 .fr1.c1.lab3 .fr1.c1.lab4  
          .fr1.c1.lab5 .fr1.c1.lab6 -pady 1m
     #Column 2 widgets
     pack .fr1.c2.surname1 .fr1.c2.firstname1 .fr1.c2.address1  
          .fr1.c2.telephone .fr1.c2.sex1 .fr1.c2.age1  
          -padx 3m -pady 1m -fill x
     #Now pack frames side by side     
     pack  .fr1.c1 .fr1.c2 -side left

     #now develop the procedure for saving the data file

     proc savecommand {} {
         #external variables have to be declared as "global"
       global surname firstnames address telno sex age
       set file [open /tmp/outfile w]
       puts $file $surname
       puts $file $firstnames
       puts $file $address
       puts $file $telno
       puts $file $sex
       puts $file $age
       close $file
       }

    #Note: In Unix this could have been written as
    #        proc savecommand {} {
    #           global surname firstnames address telno sex age
    #           exec echo $surname    > /tmp/outfile
    #           exec echo $firstnames >> /tmp/outfile
    #           exec echo $address    >> /tmp/outfile
    #           exec echo $telno      >> /tmp/outfile
    #           exec echo $sex        >> /tmp/outfile
    #           exec echo $age        >> /tmp/outfile
    #       }

    # And finally pack the Save and Quit buttons at the bottom
    pack .fr2.button1 .fr2.button2 -padx 2m -pady 1m -fill x
    pack .fr1 
    pack .fr2 -padx 2m -pady 1m  -fill x