If you add the button with:
editor.addButton('customFullscreen', {
tooltip: 'Fullscreen',
shortcut: 'Ctrl+Alt+F',
onClick: toggleCustomFullscreen,
onPostRender: function() {
var self = this;
editor.on('CustomFullscreenStateChanged', function(e) {
if (e.state) {
self.name('Close fullscreen');
//self.active(e.state); // uncomment for "pressed" look
} else {
self.name('Fullscreen');
}
});
}
});
and handle the event with
var customFullscreenState = false;
function toggleFullscreen() {
customFullscreenState = !customFullscreenState;
if (customFullscreenState) {
// do something, we are active
} else {
// do something else, we're unactive
}
editor.fire('CustomFullscreenStateChanged', {state: fullscreenState});
}
You should be able to have it look like wo different button and do two different things depending on state, but it will still just be one button that changes action and text.