Method setItemCheckable

packages/fairygui/src/widgets/PopupMenu.ts:182–196

* Set item checkable state by name * 通过名称设置菜单项可选中状态

(name: string, bCheckable: boolean)

     * 通过名称设置菜单项可选中状态
     */
    public setItemCheckable(name: string, bCheckable: boolean): void {
        const item = this._list.getChild(name);
        if (item && item instanceof GButton) {
            const c = item.getController('checked');
            if (c) {
                if (bCheckable) {
                    if (c.selectedIndex === 0) {
                        c.selectedIndex = 1;
                    }
                } else {
                    c.selectedIndex = 0;
                }
            }
        }
    }

    /**
     * Set item checked state by name