<p>我已经用python翻译了第三个:</p>
<p><a href="https://i.stack.imgur.com/Ng19u.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ng19u.png" alt="screenshot"/></a></p>
<pre><code>import tkinter as tk
from math import pi, cos, sin
class Meter(tk.Frame):
def __init__(self, master=None, **kw):
tk.Frame.__init__(self, master, **kw)
self.meter = []
self.angle = []
self.var = tk.IntVar(self, 0)
self.canvas = tk.Canvas(self, width=200, height=110,
borderwidth=2, relief='sunken',
bg='white')
self.scale = tk.Scale(self, orient='horizontal', from_=0, to=100, variable=self.var)
for j, i in enumerate(range(0, 100, 5)):
self.meter.append(self.canvas.create_line(100, 100, 10, 100,
fill='grey%i' % i,
width=3,
arrow='last'))
self.angle.append(0)
self.canvas.lower(self.meter[j])
self.updateMeterLine(0.2, j)
self.canvas.create_arc(10, 10, 190, 190, extent=108, start=36,
style='arc', outline='red')
self.canvas.pack(fill='both')
self.scale.pack()
self.var.trace_add('write', self.updateMeter) # if this line raises an error, change it to the old way of adding a trace: self.var.trace('w', self.updateMeter)
self.updateMeterTimer()
def updateMeterLine(self, a, l=0):
"""Draw a meter line (and recurse for lighter ones...)"""
oldangle = self.angle[l]
self.angle[l] = a
x = 100 - 90 * cos(a * pi)
y = 100 - 90 * sin(a * pi)
self.canvas.coords(self.meter[l], 100, 100, x, y)
l += 1
if l < len(self.meter):
self.updateMeterLine(oldangle, l)
def updateMeter(self, name1, name2, op):
"""Convert variable to angle on trace"""
mini = self.scale.cget('from')
maxi = self.scale.cget('to')
pos = (self.var.get() - mini) / (maxi - mini)
self.updateMeterLine(pos * 0.6 + 0.2)
def updateMeterTimer(self):
"""Fade over time"""
self.var.set(self.var.get())
self.after(20, self.updateMeterTimer)
if __name__ == '__main__':
root = tk.Tk()
meter = Meter(root)
meter.pack()
root.mainloop()
</code></pre>
<p>相同但没有箭头的褪色效果:</p>
<pre><code>class Meter(tk.Frame):
def __init__(self, master=None, **kw):
tk.Frame.__init__(self, master, **kw)
self.var = tk.IntVar(self, 0)
self.canvas = tk.Canvas(self, width=200, height=110,
borderwidth=2, relief='sunken',
bg='white')
self.scale = tk.Scale(self, orient='horizontal', from_=0, to=100, variable=self.var)
self.meter = self.canvas.create_line(100, 100, 10, 100,
fill='black',
width=3,
arrow='last')
self.angle = 0
self.updateMeterLine(0.2)
self.canvas.create_arc(10, 10, 190, 190, extent=108, start=36,
style='arc', outline='red')
self.canvas.pack(fill='both')
self.scale.pack()
self.var.trace_add('write', self.updateMeter) # if this line raises an error, change it to the old way of adding a trace: self.var.trace('w', self.updateMeter)
def updateMeterLine(self, a):
"""Draw a meter line"""
self.angle = a
x = 100 - 90 * cos(a * pi)
y = 100 - 90 * sin(a * pi)
self.canvas.coords(self.meter, 100, 100, x, y)
def updateMeter(self, name1, name2, op):
"""Convert variable to angle on trace"""
mini = self.scale.cget('from')
maxi = self.scale.cget('to')
pos = (self.var.get() - mini) / (maxi - mini)
self.updateMeterLine(pos * 0.6 + 0.2)
</code></pre>