树莓派 python绘图 树莓派 python ui

基于树莓派的python界面开发实例教程

• 环境测试
• 添加label实例

• 时钟程序
• 添加天气

环境测试

点击树莓派的开始菜单，找到programming-Python3(IDLE)，点击打开。

打开后如下：

在home/pi下面建立home/pi/py3prog的文件夹，专门用来存放python脚本，利用IDLE来新建一个home/pi/py3prog/digitalClock.py文件，用来存放让实例文件。

用IDLE打开刚刚新建的文件，填入以下带代码：

from tkinter import *

root = Tk()
root.titlle('this is my digital clock')
root.geometry('300x100')
app = Application(root)
app.mainloop()

保存，运行，应当出现以下界面：

添加label实例

特别注意的是__init__的下划线是由两段‘_’组成的，如果拼写为一个下划线，虽然不报错，但是运行后控件无效，不显示。

from tkinter import *

class Application(Frame):
	"""Build the basic window frame template"""

	def __init__(self, master):
		super(Application, self).__init__(master)
		self.grid()
		self.create_widgets()

	def create_widgets(self):
		self.lable1 = Label(self, text='Welcome to my window!')
		self.lable1.grid(row=0, column=0, sticky= W)

root =Tk()
root.title('Test Application window with label1')
root.geometry('300x100')
app=Application(root)
app.mainloop()

运行后结果如下：

时钟程序

from tkinter import *
import time
import threading


class Application(Frame):
        """Build the basic window frame template"""

        def __init__(self, master):
                super(Application, self).__init__(master)
                self.grid()
                self.create_widgets()

        def create_widgets(self):
                t = time.localtime()
                current_time = time.strftime('%H:%M:%S',t)
                self.lable1 = Label(self, text=current_time)
                self.lable1.grid(row=0, column=0, sticky= NSEW)
                self.lable1.config(font=('Arial',370))
                self.lable1.config(bg='black',fg='white')
                self.lable1.after(1000,self.Refresher)
                
        def Refresher(self):
                t = time.localtime()
                current_time = time.strftime('%H:%M:%S',t)
                self.lable1.configure(text=current_time)
                self.lable1.after(1000,self.Refresher)
                
root =Tk()
root.title('Test Application window with label1')
width= root.winfo_screenwidth()
height= root.winfo_screenheight()
root.geometry("%dx%d" % (width, height))
root.config(bg='black')
app=Application(root)      
app.mainloop()

运行后如下：

添加天气

时钟写完以后，觉得有点空洞，决定加入天气情况的信息。经初步调研，选择用‘openweathermap’的API，官网见此。
此提供商有集成好的python包，注册一个账号可免费获取（目前免费版三小时更新一次）。需要导入“pyowm”包。

官网有示例文档。

代码如下（特别备注：pyowm.OWM括号里面的是API Key，去官网注册一个账户，会自动生成一个，代码里的是示例，我已更改过，不可用，请替换成自己的）：

from tkinter import *
import time
import threading
import pyowm
import json


class Application(Frame):
        """Build the basic window frame template"""

        def __init__(self, master):
                super(Application, self).__init__(master)
                self.grid()
                self.create_widgets()

        def create_widgets(self):
                t = time.localtime()
                current_time = time.strftime('%H:%M:%S',t)
                self.lable1 = Label(self, text=current_time)
                self.lable1.grid(row=0, column=0, sticky= NSEW)
                self.lable1.config(font=('Arial',370))
                self.lable1.config(bg='black',fg='white')
                self.lable1.after(1000,self.Refresher)
                owm = pyowm.OWM('02f7e0006144dc293dcd49ec8c4750dd')
                mgr = owm.weather_manager()
                weather = mgr.weather_at_place('Shanghai,CN').weather
#                sf = owm.weather_at_place('London,uk')
                temp_dict_celsius = weather.temperature('celsius')
                wetherInfo = json.dumps(temp_dict_celsius)
                self.labelweatherlocal = Label(self,text = current_time + wetherInfo)
                self.labelweatherlocal.grid(row=1, column=0, sticky= NSEW)
                self.labelweatherlocal.config(font=('Arial',34))
                self.labelweatherlocal.config(bg='black',fg='white')
                self.labelweatherlocal.after(600000,self.weatherRefresher)
               
        def Refresher(self):
                t = time.localtime()
                current_time = time.strftime('%H:%M:%S',t)
                self.lable1.configure(text=current_time)
                self.lable1.after(1000,self.Refresher)

        def weatherRefresher(self):
                t = time.localtime()
                current_time = time.strftime('%H:%M:%S',t)
                owm = pyowm.OWM('02f7e0006144dc293dcd49ec8c4750dd')
                mgr = owm.weather_manager()
                weather = mgr.weather_at_place('Shanghai,CN').weather
#                sf = owm.weather_at_place('London,uk')
                temp_dict_celsius = weather.temperature('celsius')
                wetherInfo = json.dumps(temp_dict_celsius)
                self.labelweatherlocal.configure(text = current_time + wetherInfo)
                self.labelweatherlocal.after(600000,self.weatherRefresher)
                

                
root =Tk()
root.title('Test Application window with label1')
width= root.winfo_screenwidth()
height= root.winfo_screenheight()
root.geometry("%dx%d" % (width, height))
root.config(bg='black')
app=Application(root)      
app.mainloop()

运行结果如下：

下面返回的是时间（用以显示更新时间，目前十分钟更新一次），后面会写一个好看的窗口把数据搞得好看些。目前返回信息依次是当前温度、最高温度、最低温度、体感温度。作者在上海，所以参数传进去的是上海。