### 把matplotlib包裝成獨立視窗
```python
class Plot2D(Frame):
    def __init__(self, parent, dataCollector, **kwargs):
        Frame.__init__(self, parent.mainWindow, **kwargs)

        self.parent = parent
        self.mainWindows = Toplevel(parent.mainWindow)
        self.mainWindows.title("AF State")
        self.figure = plt.Figure(figsize=(9,5), dpi=100)
        self.figure.suptitle('AF value plot', fontsize=16)
        self.ax = self.figure.add_subplot(111)
        self.canvas = FigureCanvasTkAgg(self.figure, master=self.mainWindows)
        self.canvas.get_tk_widget().pack(fill='both')
        self.axline = None

        self.dataCollector = dataCollector
        self.dataCollector.start()

    def close(self):
        print("Plot2D close")
        self.mainWindows.destroy()
        self.dataCollector.stop()
        self.dataCollector = None

    def draw(self):
        if self.dataCollector:
            datax, datay = self.dataCollector.getPlotData()
            self.ax.clear()
            self.ax.set_xlabel('Last {} datas'.format(self.dataCollector.getDataLength()))
            self.axline, = self.ax.plot(datax, datay)
            self.canvas.draw()

    def getWindow(self):
        return self.mainWindows

    def getLastData(self):
        return self.dataCollector.getLastData()
```

其中這一行：
```python
self.mainWindows = Toplevel(parent.mainWindow)
```
是用來開一個新的視窗，其中的`parent.mainWindow`就是用`tk.TK()`所產生出來的root。

因為需要一直更新資料，所以需要的一個`DataCollector`來提供資料，`DataCollector`會提供畫圖需要的list，如：
```python
datax, datay = self.dataCollector.getPlotData()
```

`DataCollector`的定義如下：
```python
class AfStateCollector(threading.Thread):
    def __init__(self, dataLength=100, pollingInterval=0.033):
        threading.Thread.__init__(self)
        self.dataLength = dataLength
        self.pollingInterval = pollingInterval
        self.stopEvent = threading.Event()
        self.data = []
        self.xdata = []

    def run(self):
        while True:
            if self.stopEvent.is_set():
                break

            afValue = self.readAf()
            self.data.append(afValue)
            self.xdata.append(len(self.xdata))
            if len(self.data) > self.dataLength:
                self.data = self.data[-self.dataLength:]
                self.xdata = list(range(self.dataLength))

            # print(f'afValue = {afValue}')
            time.sleep(self.pollingInterval)

        print("AfStateCollector stopped.")

    def readAf(self):
        ReadTestXUreg_cmd = "lvreg testxu read 10"
        ReadTestXUreg_cmd_process = subprocess.Popen(ReadTestXUreg_cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)

        outstring, err = ReadTestXUreg_cmd_process.communicate()
        outstring = outstring.strip().decode('utf-8')
        outstring = int(outstring, 16)
        outstring_H = (outstring & 0xFF00) / 256
        outstring_L = outstring & 0xFF
        outAFStat = int(outstring_L * 256 + outstring_H)

        return outAFStat
```

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