Width of ButtonEdit/DateEdit/ComboBox

When using BUTTONEDIT/COMBOBOX/DATEEDIT fields, it is recommended that you account for the width of the widget button in addition to the input area.

The problem with BUTTONEDIT, DATEEDIT and COMBOBOX in versions prior to 1.30 is that a field [b ] got the width 3, the same width as an edit field with the same layout.

For example:

  [e  ]
  [b  ]
EDIT e=formonly.e; 
BUTTONEDIT b=formonly.b; 

In this example, the outer (visual) width of both elements was the same, but the edit portion of "b" was much smaller, because the button did not count at all. (In practice this meant that on average only one and a half characters of "b" was visible). However, you could input 3 characters! This resulted in a BUTTONEDIT where only one character was visible and inputting more than one character was possible.

Starting with version 1.30, for the Button, the Form Compiler subtracts two character positions from the width of BUTTONEDIT/COMBOBOX/DATEEDIT. This is possible because now the form compiler differentiates the width of the widget from the width of the entry part.

In fact, there is no visual difference between version 1.20 and 1.30 regarding this example, but in version 1.30 you can only enter one character, which is visually more correct.

In the example the BUTTONEDIT aligns with the Edit; that's why the Edit part of the BUTTONEDIT is usually still a bit bigger than one character (this depends on the button size, but if a button edit is contained by an HBox, it will get the exact size of "width" multiplied by the average character pixel width.

To express the BUTTONEDIT/COMBOBOX/DATEEDIT layout more visually, it is possible to specify:

  [e  ]
  [b- ]

the "-" sign marks the end of the edit portion and the beginning of the button portion ( edit width ="1", widget width ="3" ).

The two characters are also subtracted for a BUTTONEDIT which is child of an HBox.

   [b  :]

gets also width="1" , but no widget width, because the HBox stacks the elements horizontally without needing widget width definition.

The two extra characters are only used to show the real size relations more WYSIWYG, and to have the same calculation as in a field without an HBox parent.

  [e1:e2:e3:     ]
  [b1  :b2  :b3  ]

shows that three BUTTONEDIT fields are much larger than three EDIT fields with the same width.

You can even write:

  [e1:e2:e3:     ]
  [b1- :b2- :b3- ]


  [e1:e2:e3:  ]

to use slim buttons and

  [e1:e2:e3:        ]
  [b1-  :b2-  :b3-  ]

if one uses large buttons to get the maximum WYSIWYG effect.

Please note that buttons do not grow if two characters "- " are expanded to three characters "- "; the button always computes its size from the image used, it's just reserves more space in the form to match the real size.