<mat-button-toggle> are on/off toggles with the appearance of a button. These toggles can be
configured to behave as either radio-buttons or checkboxes. While they can be standalone, they are
typically part of a mat-button-toggle-group.
By default, mat-button-toggle-group acts like a radio-button group- only one item can be selected.
In this mode, the value of the mat-button-toggle-group will reflect the value of the selected
button and ngModel is supported.
Adding the multiple attribute allows multiple items to be selected (checkbox behavior). In this
mode the values of the toggles are not used, the mat-button-toggle-group does not have a value,
and ngModel is not supported.
By default, the appearance of mat-button-toggle-group and mat-button-toggle will follow the
latest Material Design guidelines. If you want to, you can switch back to the appearance that was
following the previous Material Design spec by using the appearance input. The appearance can
be configured globally using the MAT_BUTTON_TOGGLE_DEFAULT_OPTIONS injection token.
Default appearance:
Legacy appearance:
The button-toggles will present themselves as either checkboxes or radio-buttons based on the
presence of the multiple attribute.
For button toggles containing only icons, each button toggle should be given a meaningful label via
aria-label or aria-labelledby.
For button toggle groups, each group should be given a meaningful label via aria-label or
aria-labelledby.
The button-toggles can be rendered in a vertical orientation by adding the vertical attribute.