<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 the toggles are not used, the mat-button-toggle-group does not have a value, and ngModel is not supported.
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.