Python GUI编程入门(31)-Treeview控件

Treeview是Tkinter8.5新引入的控件，可以用于实现较为复杂的GUI界面。本文使用一个FileBrowser实例来说明它的用法。

构建主窗口和退出菜单的代码和前一篇文章几乎相同：

root = Tk() root.title('Tkinter Treeview and PanedWindow Demo V1.0') root.grid_rowconfigure(0, weight=1) root.grid_columnconfigure(0, weight=1) screen_w = root.winfo_screenwidth() screen_h = root.winfo_screenheight() root.maxsize(width=screen_w, height=screen_h) rw = int(screen_w / 2) rh = int(screen_h / 2) root.geometry('{}x{}+{:g}+{:g}'.format(rw, rh, rw / 2, rh / 2)) top_menu = Menu(root) root.config(menu=top_menu) file_menu = Menu(top_menu, tearoff=False) top_menu.add_cascade(label='File', menu=file_menu) file_menu.add_command(label="Exit", command=root.quit) 

构建一个水平方向的PanedWindow控件，grid布局时sticky属性设置为四面填充。

paned_window = PanedWindow(root, orient=HORIZONTAL)paned_window.grid(row=0, column=0, sticky='eswn') 

构建管理左侧控件的Frame对象：

tree_area = Frame(paned_window) tree_area.grid_rowconfigure(0, weight=1) tree_area.grid_columnconfigure(0, weight=1) paned_window.add(tree_area) 

准备Treeview图标文件：

cur_path = os.path.abspath(os.path.dirname(__file__)) pc_image = PhotoImage(file=cur_path + '\\images\\pc.png') drive_image = PhotoImage(file=cur_path + '\\images\\drive.png') folder_image = PhotoImage(file=cur_path + '\\images\\folder.png') file_image = PhotoImage(file=cur_path + '\\images\\file.png') 

构建Treeview控件。将show属性指定为’tree’可以消除顶部的标题行。

tree_view = Treeview(tree_area, show='tree', selectmode='browse') tree_view.grid(row=0, column=0, sticky='nsew') 

添加水平和垂直滚动条：

scroll_ty = Scrollbar(tree_area, orient=VERTICAL, command=tree_view.yview) scroll_ty.grid(row=0, column=1, sticky=N+S) tree_view['yscrollcommand']=scroll_ty.set scroll_tx = Scrollbar(tree_area, orient=HORIZONTAL, command=tree_view.xview) scroll_tx.grid(row=1, column=0, sticky=E+W) tree_view['xscrollcommand']=scroll_tx.set 

增加根节点及驱动器节点：

pc_node= tree_view.insert('', 'end', text=os.environ.get('COMPUTERNAME'), image=pc_image, open=False) for c in string.ascii_uppercase: disk = c + ':' if os.path.isdir(disk): drive_node = tree_view.insert(pc_node, 'end', text=disk, image=drive_image) 

给定节点，获得节点路径的函数：

def node_path(node): path = '' parent = node while parent: node_text = tree_view.item(parent, 'text') if len(path) > 0: path = os.path.join(node_text, path) else: path = node_text parent = tree_view.parent(parent) return path 

由于磁盘目录的结构一般都会非常复杂，因此本示例采用以下策略：

1. 展开节点时才会读入下级节点目录结构
2. 关闭节点时删除下级节点的目录结构

def open_node(event): focus = tree_view.focus() for node in tree_view.get_children(focus): insert_child_items(node) tree_view.bind('<<TreeviewOpen>>', open_node) def close_node(event): focus = tree_view.focus() for node in tree_view.get_children(focus): children = tree_view.get_children(node) for c in children: tree_view.delete(c) 

insert_child_items的实现如下：

def insert_child_items(parent_node): path = node_path(parent_node) if os.path.isdir(path): try: dir_items = os.scandir(path) for item in dir_items: if item.is_dir() and ('.