main.py
from kivy.base import EventLoop
from kivy.config import Config
from kivy.graphics import Color, Line
from kivy.uix.behaviors import ToggleButtonBehavior
from kivy.uix.togglebutton import ToggleButton
from kivy.uix.widget import Widget
from kivy.utils import get_color_from_hex
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.popup import Popup
from kivy.clock import Clock
CURSOR = (
' @@@@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @@@@ ',
' ',
'@@@@@@ @@@@ @@@@@@ ',
'@----@ @--@ @----@ ',
'@----@ @--@ @----@ ',
'@@@@@@ @@@@ @@@@@@ ',
' ',
' @@@@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @@@@ ',
' ',
' ',
' ',
' ',
' ',
' ',
)
class Update_Location(Widget):
pass
class CanvasWidget(Widget):
line_width = 2
def on_touch_down(self, touch):
if Widget.on_touch_down(self, touch):
return
with self.canvas:
touch.ud['current_line'] = Line(
points=(touch.x, touch.y),
width=self.line_width)
def on_touch_move(self, touch):
if 'current_line' in touch.ud:
touch.ud['current_line'].points += (touch.x, touch.y)
def set_color(self, new_color):
self.last_color = new_color
self.canvas.add(Color(*new_color))
def set_line_width(self, line_width='Normal'):
self.line_width = {
'Thin': 1, 'Normal': 2, 'Thick': 4
}[line_width]
def clear_canvas(self):
saved = self.children[:]
self.clear_widgets()
self.canvas.clear()
for widget in saved:
self.add_widget(widget)
self.set_color(self.last_color)
def start_server(self):
host = '127.0.0.1'
port = 5000
notification_text="Server started on host: "+host+" and port: "+str(port)
server_start=Popup(title='Notification',content=Label(text=notification_text),size_hint=(.75,.75),auto_dismiss=True)
server_start.open()
Clock.schedule_interval(server_start.dismiss, 3)
class PaintApp(App):
def build(self):
EventLoop.ensure_window()
if EventLoop.window.__class__.__name__.endswith('Pygame'):
try:
from pygame import mouse
a, b = pygame_compile_cursor()
mouse.set_cursor((24, 24), (9, 9), a, b)
except:
pass
#boxlayout
self.layout = BoxLayout(orientation='vertical')
self.canvas_widget = CanvasWidget()
self.canvas_widget.set_color(
get_color_from_hex('#2980b9'))
self.layout.add_widget(self.canvas_widget)
#self.layout.add_widget(Label(text="Started Server : False , Connected to Server : False",color=(1,1,1),size_hint=(1, .1)))
return self.layout
#return self.canvas_widget
class RadioButton(ToggleButton):
def _do_press(self):
if self.state == 'normal':
ToggleButtonBehavior._do_press(self)
def pygame_compile_cursor(black='@', white='-'):
aa, bb = [], []
a = b = 0
i = 8
for s in CURSOR:
for c in s:
a <<= 1
b <<= 1
i -= 1
if c == black:
a |= 1
b |= 1
elif c == white:
b |= 1
if not i:
aa.append(a)
bb.append(b)
a = b = 0
i = 8
return tuple(aa), tuple(bb)
if __name__ == '__main__':
Config.set('graphics', 'width', '960')
Config.set('graphics', 'height', '540') # 16:9
# Config.set('graphics', 'resizable', '0')
# Config.set('input', 'mouse', 'mouse,disable_multitouch')
from kivy.core.window import Window
Window.clearcolor = get_color_from_hex('#ffffff')
PaintApp().run()
server.py
import socket
def start_server(host,port):
s = socket.socket()
s.bind((host,port))
s.listen(1)
c, addr = s.accept()
print "Connection from: " + str(addr)
while True:
data = c.recv(1024)
if not data:
break
print "from connected user: " + str(data)
data = str(data).upper()
print "sending: " + str(data)
c.send(data)
c.close()
if __name__ == '__main__':
start_server()
以上是我的简单绘画应用程序的代码（采用kivy blue print）。
我的目标是在localhost上的一个应用程序上启动服务器，然后其他应用程序连接到它。那些可以连接到它的人应该从他们连接的服务器上更新他们的画布。如何发送数据和更新画布。我使用python的套接字库在上面的代码中创建了一个服务器。
我不想使用http请求/线程来代替与套接字建立连接并使用async.io。
答案 0 :(得分：4)
我使用支持post的/ canvas端点创建了一个快速的REST烧瓶服务。我还创建了CanvasWidget类的一个line成员来保存如何重新创建数据以将其发送到服务器。我曾考虑逐像素地进行操作，但我认为跟踪Line创建更加优雅，并且如果有要求的话会支持撤消重做功能。
路线
main.py
from kivy.app import App
from kivy.base import EventLoop
from kivy.config import Config
from kivy.graphics import Color, Line
from kivy.uix.behaviors import ToggleButtonBehavior
from kivy.uix.togglebutton import ToggleButton
from kivy.uix.widget import Widget
from kivy.utils import get_color_from_hex
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.popup import Popup
from kivy.clock import Clock
from kivy.network.urlrequest import UrlRequest
import flask
CURSOR = (
' @@@@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @@@@ ',
' ',
'@@@@@@ @@@@ @@@@@@ ',
'@----@ @--@ @----@ ',
'@----@ @--@ @----@ ',
'@@@@@@ @@@@ @@@@@@ ',
' ',
' @@@@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @--@ ',
' @@@@ ',
' ',
' ',
' ',
' ',
' ',
' ',
)
class Update_Location(Widget):
pass
class CanvasWidget(Widget):
line_width = 2
lines = []
def __init__(self, **kwargs):
super(CanvasWidget, self).__init__(**kwargs)
self._keyboard = Window.request_keyboard(self._keyboard_closed, self)
self._keyboard.bind(on_key_down=self._on_keyboard_down)
def _keyboard_closed(self):
self._keyboard.unbind(on_key_down=self._on_keyboard_down)
self._keyboard = None
def _on_keyboard_down(self, keyboard, keycode, text, modifiers):
if keycode[1] == 's':
print 'send'
json = flask.json.dumps(self.lines)
req = UrlRequest('http://127.0.0.1:5000/canvas', req_body=json)
elif keycode[1] == 'r':
print 'receive'
req = UrlRequest('http://127.0.0.1:5000/canvas', self.load_state)
def on_touch_down(self, touch):
if Widget.on_touch_down(self, touch):
return
with self.canvas:
touch.ud['current_line'] = Line(
points=(touch.x, touch.y),
width=self.line_width)
self.lines.append({'points':[touch.x,touch.y], 'width':self.line_width})
def on_touch_move(self, touch):
if 'current_line' in touch.ud:
touch.ud['current_line'].points += (touch.x, touch.y)
self.lines[-1]['points'].append(touch.x)
self.lines[-1]['points'].append(touch.y)
def set_color(self, new_color):
self.last_color = new_color
self.canvas.add(Color(*new_color))
def set_line_width(self, line_width='Normal'):
self.line_width = {
'Thin': 1, 'Normal': 2, 'Thick': 4
}[line_width]
def clear_canvas(self):
saved = self.children[:]
self.clear_widgets()
self.canvas.clear()
for widget in saved:
self.add_widget(widget)
self.set_color(self.last_color)
def load_state(self, req, results):
print 'load_state req', repr(req)
print 'load_state results', repr(results)
#needs some validation here
self.clear_canvas()
with self.canvas:
for line in results:
Line(points=line['points'], width=line['width'])
self.line = results
def start_server(self):
host = '127.0.0.1'
port = 5000
notification_text="Server started on host: "+host+" and port: "+str(port)
server_start=Popup(title='Notification',content=Label(text=notification_text),size_hint=(.75,.75),auto_dismiss=True)
server_start.open()
Clock.schedule_interval(server_start.dismiss, 3)
class PaintApp(App):
def build(self):
EventLoop.ensure_window()
if EventLoop.window.__class__.__name__.endswith('Pygame'):
try:
from pygame import mouse
a, b = pygame_compile_cursor()
mouse.set_cursor((24, 24), (9, 9), a, b)
except:
pass
#boxlayout
self.layout = BoxLayout(orientation='vertical')
self.canvas_widget = CanvasWidget()
self.canvas_widget.set_color(
get_color_from_hex('#2980b9'))
self.layout.add_widget(self.canvas_widget)
#self.layout.add_widget(Label(text="Started Server : False , Connected to Server : False",color=(1,1,1),size_hint=(1, .1)))
return self.layout
#return self.canvas_widget
class RadioButton(ToggleButton):
def _do_press(self):
if self.state == 'normal':
ToggleButtonBehavior._do_press(self)
def pygame_compile_cursor(black='@', white='-'):
aa, bb = [], []
a = b = 0
i = 8
for s in CURSOR:
for c in s:
a <<= 1
b <<= 1
i -= 1
if c == black:
a |= 1
b |= 1
elif c == white:
b |= 1
if not i:
aa.append(a)
bb.append(b)
a = b = 0
i = 8
return tuple(aa), tuple(bb)
if __name__ == '__main__':
Config.set('graphics', 'width', '960')
Config.set('graphics', 'height', '540') # 16:9
# Config.set('graphics', 'resizable', '0')
# Config.set('input', 'mouse', 'mouse,disable_multitouch')
from kivy.core.window import Window
Window.clearcolor = get_color_from_hex('#ffffff')
PaintApp().run()
server.py
from flask import Flask, jsonify, request, json
app = Flask(__name__)
data = []
@app.route('/canvas', methods = ['GET', 'POST'])
def canvas():
global data
if request.method == 'GET':
tmp = jsonify({})
tmp.set_data(json.dumps(data))
return tmp
if request.method == 'POST':
data = json.loads(request.data)
tmp = jsonify({})
tmp.set_data(json.dumps(data))
return tmp
if __name__ == '__main__':
app.run(debug=True)