Checkbox

Purpose

A checkbox is a control that permits the user to make multiple selections from a number of options. Checkboxes are used to toggle an option on or off, or to select or deselect an item. Users make a decision between two clearly opposite choices, e.g. ‘on vs. off’, ‘apply vs. don’t apply’, ‘show vs. hide’.

Guidelines

Is this the right control?

  • Use checkboxes for non-exclusive options that have clear alternatives. Mutually exclusive options should use a set of radio buttons or a combo box.

../../_images/Ambiguous_Opposite_Bad.qml.png

Don’t.
Don’t use a checkbox if the opposite is ambiguous.

../../_images/Ambiguous_Opposite_Good.qml.png

Do.
Use two radio buttons to remove the need to guess.

  • For more than five options, use either a list view or the dual-list pattern in case of multiple selections.

  • Don’t use the selection to perform commands.

../../_images/No_Command_2_Bad.qml.png

Don’t.
Don’t use the selection to perform commands.

../../_images/No_Command_2_Good.qml.png

Do.
Consider using a push button instead.

Behavior

  • Checking a checkbox should always “enable” an option or change the state of an option to “on”. Checking a negative or disabling option is a double negative and causes confusion and errors.

../../_images/Checkbox_Enable_Bad.qml.png

Don’t.
Don’t use checkboxes for negatives.

../../_images/Checkbox_Enable_Good.qml.png

Do.
Use checkboxes for positives.

  • Use the mixed state only to indicate that an option is set for some, but not all, child objects. Mixed state must not be used to represent a third state.

Example for mixed state.
  • Users must not be able to set a mixed state directly.

  • Clicking a mixed state checkbox enables all child objects.

  • Don’t use sliding switches in Desktop applications. They only offer good user interaction on touch screens, so they should only be used in applications for mobile devices.

../../_images/Checkbox_Switch_Desktop.qml.png

Don’t.
Don’t use sliding switches on desktop.

../../_images/Checkbox_Switch_Mobile.qml.png

Do.
Do use sliding switches on mobile.

Appearance

If you are using Qt Widgets you should use one of Qt’s Layout classes, which will take care of the layout and spacing of your controls.

  • The text of a checkbox is on the right of its tick rectangle, which can make it difficult to avoid blank areas on the left side of the form. To keep the layout of the form balanced you can use one of the following approaches:

    • Group checkboxes together in the widget column and add a label describing the group in the label column.

      Grouped checkboxes
    • If all else fails, add a label describing the checkbox on the left side of the checkbox, then set the text of the checkbox to “Enabled”, “On”, or similar.

      Using a separate title label for the checkbox.
  • When options are subordinate to a checkbox (e.g. Audio level can only be set if the Activate Audio option is selected), this relation should be visualized by indenting the sub-options. There are two options to do so:

    • When you are using a left-aligned checkbox, indent the sub-options by using a horizontal spacer of SizeType “Minimum”.

      Aligning sub-options with a horizontal spacer of SizeType "Minimum".
    • When you are using a checkbox that is placed right to its label, indent the sub-options in the same vertical axis as the checkbox.

      Aligning sub-options with the same vertical axis as the checkbox itself.|
  • If activating a choice affects the appearance or the enabled state of other controls, place them next to the checkbox (group).

  • Align checkboxes vertically rather than horizontally, as this makes them easier to scan visually. Use horizontal or rectangular alignments only if they greatly improve the layout of the window.

  • If certain controls in a configuration dialog are only relevant if a certain checkbox is checked (i.e. they are dependent controls), disable them instead of hiding them if that checkbox is unchecked.

  • Don’t separate checkbox and label. Clicking on both the box and the label should toggle the option.

  • Don’t add line breaks. If necessary, place an additional label below the checkbox.

../../_images/Checkbox_Alignment_Bad.qml.png

Don’t.
Don’t use linebreaks in a checkbox’s label.

../../_images/Checkbox_Alignment_Good.qml.png

Do.
Add another label if more explanation is required.

  • Label a group of checkbox with a descriptive caption to the top left of the group (cf. alignment).

  • Create a buddy relation so access keys are assigned.

  • Use sentence style capitalization for checkbox items.

Code

Kirigami

Plasma components

  • Plasma CheckBox