I created a hidden button "show" with the "icon-add" image. when the button "hide" is clicked, it get hidden and the button "show" get shown.
toolbar: {
name: 'toolbar',
items: [
{ type: 'button', id: 'hide', caption: 'Menü', img: 'icon-delete' },
{ type: 'button', id: 'show', hidden: 'true', caption: 'Menü', img: 'icon-add' }
],
onClick: function (target, data) {
if (target == 'hide' ) {w2ui['layout'].toggle('left', window.instant);
this.hide('hide');
this.show('show');
}
if (target == 'show' ) {w2ui['layout'].toggle('left', window.instant);
this.hide('show');
this.show('hide');
}
}
}