Critique of Theme 'clam'

The theme clam encompasses some aspects from a modern Graphical User Interface. It shuns pseudo-3d and uses shape to communicate function. This positive attributes of 'clam' are the reason for me to write a critique about it.

Tk Controls using clam


Clam's entry features a solid, slightly rounded borders. Highlighting is in a different colour and inside the control.

The typical entry design can now being described as universally adhering to pseudo-3d.

Highlighting is better than in other clam controls; but to small (1 pixel) and inside the control, making it difficult to see it on high resolution displays such as in laptops. Using highlighting inside the control tends to increase the control's size –fortunately not so in this case.


Uses a flat outline with a solid border, square edges and a raised (pseudo-3d) slider. There is no highlighting.

This design is similar to Tk's scale. The control has a flat appearance.


The button has a small raised (pseudo-3d) border. Highlighting is done using a stippled line inside the control. The edges are slightly rounded – same as with the entry control.

The stippled line, indicating keyboard focus, will be completely unseeable on high resolution and / or high contrast displays. These technique is justly abandoned virtually everywhere else, now.

There is to much white space inside the button. I did reduce the internal white space to '-padding 2', which is OK.

To increase the font size and thus the control is a better approach to enlarge them. An overuse of white space inside active controls disrupts the visual cues of a control. Using internal focus highlighting yields the same negative effect.


Focus highlighting is the same as with buttons.

The check-indicator uses a sunken (pseudo-3d) border with white background. The check mark 'x' is used to depict its active state.

Depicting checkbuttons via a sunken indicator is a curiosity. A button (and a checkbutton is a button) is usually raised. Using a pseudo-3d sunken border is inconsistent with clam's general design –not even the entry uses a sunken border.

The 'x'-symbol, marking the active state, is an unfortunate choice. The 'x'-symbol has been frequently abused to signify terms such as 'cancel' or 'delete'. On paper, I use a 'check mark' (look into a dictionary) to indicate that the statement is correct etc.; whereas the 'x'-mark usually indicates something important is still pending.


Focus highlighting is the same as with buttons.

The check-indicator uses a sunken (pseudo-3d) border with a white background. A dot is used to indicate the active state.

The dot as an indicator is ok, otherwise the critique is the same as for the checkbutton.


The menubutton is a button with an additional menu-indicator. What was written about button does apply to the menubutton, too.

The menubutton indicator is a filled, down pointing angle –as it is frequently seen for comboboxes. The indicator is out of alignment with the text on the menubutton. The indicator does visually dominate the whole control –by being filled. The control could be improved by using two smaller filled angles pointing in opposite directions (see AQUA® for example). To leave the single angle unfilled would be an option, too; in this case text and angle have to be aligned.

There are four different ( scale, entry, button and combobox) highlighting mechanisms in clam alone, none of it identical to Tk.