python系列5：python图形界面PySimpleGUI
1. 简介
使用pip安装即可。注意如果是python2.7版本，安装的是pySimpleGUI27。
pySimpleGUI可以绘制的界面元素可以从官方case中看出：
import PySimpleGUI
pySimpleGUI.main()
内部代码如下：
import PySimpleGUI as sg
sg.ChangeLookAndFeel('GreenTan')
# ------ Menu Definition ------ #
menu_def = [['File', ['Open', 'Save', 'Exit', 'Properties']],
['Edit', ['Paste', ['Special', 'Normal', ], 'Undo'], ],
['Help', 'About...'], ]
# ------ Column Definition ------ #
column1 = [[sg.Text('Column 1', background_color='#F7F3EC', justification='center', size=(10, 1))],
[sg.Spin(values=('Spin Box 1', '2', '3'), initial_value='Spin Box 1')],
[sg.Spin(values=('Spin Box 1', '2', '3'), initial_value='Spin Box 2')],
[sg.Spin(values=('Spin Box 1', '2', '3'), initial_value='Spin Box 3')]]
layout = [
[sg.Menu(menu_def, tearoff=True)],
[sg.Text('All graphic widgets in one window!', size=(30, 1), justification='center', font=("Helvetica", 25), relief=sg.RELIEF_RIDGE)],
[sg.Text('Here is some text.... and a place to enter text')],
[sg.InputText('This is my text')],
[sg.Frame(layout=[
[sg.Checkbox('Checkbox', size=(10,1)), sg.Checkbox('My second checkbox!', default=True)],
[sg.Radio('My first Radio! ', "RADIO1", default=True, size=(10,1)), sg.Radio('My second Radio!', "RADIO1")]], title='Options',title_color='red', relief=sg.RELIEF_SUNKEN, tooltip='Use these to set flags')],
[sg.Multiline(default_text='This is the default Text should you decide not to type anything', size=(35, 3)),
sg.Multiline(default_text='A second multi-line', size=(35, 3))],
[sg.InputCombo(('Combobox 1', 'Combobox 2'), size=(20, 1)),
sg.Slider(range=(1, 100), orientation='h', size=(34, 20), default_value=85)],
[sg.InputOptionMenu(('Menu Option 1', 'Menu Option 2', 'Menu Option 3'))],
[sg.Listbox(values=('Listbox 1', 'Listbox 2', 'Listbox 3'), size=(30, 3)),
sg.Frame('Labelled Group',[[
sg.Slider(range=(1, 100), orientation='v', size=(5, 20), default_value=25),
sg.Slider(range=(1, 100), orientation='v', size=(5, 20), default_value=75),
sg.Slider(range=(1, 100), orientation='v', size=(5, 20), default_value=10),
sg.Column(column1, background_color='#F7F3EC')]])],
[sg.Text('_' * 80)],
[sg.Text('Choose A Folder', size=(35, 1))],
[sg.Text('Your Folder', size=(15, 1), auto_size_text=False, justification='right'),
sg.InputText('Default Folder'), sg.FolderBrowse()],
[sg.Submit(tooltip='Click to submit this window'), sg.Cancel()]
]
window = sg.Window('Everything bagel', default_element_size=(40, 1), grab_anywhere=False).Layout(layout)
event, values = window.Read()
sg.Popup('Title',
'The results of the window.',
'The button clicked was "{}"'.format(event),
'The values are', values)
要导出exe的话，安装PyInstaller，然后执行pyinstaller -wF 程序.py即可。
2. 全局设置
可以对window/row/element使用setOptions方法，可配参数如下：
icon=None
button_color=(None,None)
element_size=(None,None),
margins=(None,None),
element_padding=(None,None)
auto_size_text=None
auto_size_buttons=None
font=None
border_width=None
slider_border_width=None
slider_relief=None
slider_orientation=None
autoclose_time=None
message_box_line_width=None
progress_meter_border_depth=None
progress_meter_style=None
progress_meter_relief=None
progress_meter_color=None
progress_meter_size=None
text_justification=None
text_color=None
background_color=None
element_background_color=None
text_element_background_color=None
input_elements_background_color=None
element_text_color=None
input_text_color=None
scrollbar_color=None, text_color=None
debug_win_size=(None,None)
window_location=(None,None)
tooltip_time = None
3. 事件处理
PySimpleGUI的事件处理使用while循环实现，下面是一个例子：
import PySimpleGUI as sg
layout = [[sg.Text('Persistent window')],
[sg.Input(key = 'a')],
[sg.Input(key = 'b')],
[sg.Button('Read'), sg.Exit()]]
window = sg.Window('Window that stays open').Layout(layout)
while True:
event, values = window.Read()
if event is None or event == 'Exit':
break
print(event, values)
window.Close()
3.1 获取部件
使用window.Element(部件名称).update()可以获取到部件并更改值（部分部件可更改属性，参考API文档），例如：
import PySimpleGUI as sg
layout = [ [sg.Text('My layout', key='_TEXT_')],
[sg.Button('Read')]]
window = sg.Window('My new window').Layout(layout)
while True: # Event Loop
event, values = window.Read()
if event is None:
break
window.Element('_TEXT_').Update('My new text value')
3.2 blocking事件响应
Layout的read方法会等待用户进行响应，称为blocking event，分为三种情况：
第一种响应是按钮点击响应。每次用户点击按钮后，会返回两个值，一个是按钮的名称，一个是返回值。返回值是字典的形式，key是部件name，value是对应的值。
第二种响应是Enter响应。在属性中设置change_submits = True即可，这样按下Enter键就会触发响应。
第三种响应是鼠标/键盘事件。在属性中设置return_keyboard_events = True即可。
import PySimpleGUI as sg
with sg.Window("Keyboard Test", return_keyboard_events=True, use_default_focus=False) as window:
text_elem = sg.Text("", size=(18, 1))
layout = [[sg.Text("Press a key or scroll mouse")],
[text_elem]]
window.Layout(layout)
# ---===--- Loop taking in user input --- #
while True:
event, value = window.Read()
if event is None:
break
text_elem.Update(event)
window.Close()
3.3 non-blocking事件响应
如果想定时响应，比如动画每1/24秒刷新一次页面，可以使用non-blocking event。设置read方法的timeout属性即可（时间单位为毫秒），此时返回的event == sg.TIMEOUT_KEY。
import PySimpleGUI as sg
layout = [ [sg.Text('non-blocking example', key='_TEXT_')],
[sg.Button('Read')]]
window = sg.Window('My new window').Layout(layout)
while True: # Event Loop
event, values = window.Read(timeout=3000)
if event is None:
break # the use has closed the window
if event == sg.TIMEOUT_KEY:
print("Nothing happened")
else:
print(event)
window.Close()