[plot] first sketch of plot screen

plot_screen.py

@@ -0,0 +1,36 @@
+from PyQt5.QtWidgets import QHBoxLayout, QPushButton, QVBoxLayout, QWidget
+from PyQt5.QtCore import QObject, pyqtSignal, Qt
+import matplotlib
+matplotlib.use('Qt5Agg')
+from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg
+from matplotlib.figure import Figure
+
+class MplCanvas(FigureCanvasQTAgg):
+
+    def __init__(self, parent=None, width=5, height=4, dpi=100):
+        fig = Figure(figsize=(width, height), dpi=dpi)
+        self.axes = fig.add_subplot(111)
+        super(MplCanvas, self).__init__(fig)
+
+
+class PlotScreen(QWidget):
+    close_signal = pyqtSignal()
+    
+    def __init__(self, parent) -> None:
+        super().__init__(parent=parent)
+        sc = MplCanvas(self, width=5, height=4, dpi=100)
+        sc.axes.plot([0,1,2,3,4], [10,1,20,3,40])
+        
+        self.setLayout(QVBoxLayout())
+        self.layout().addWidget(sc)
+        
+        close_btn = QPushButton("close")
+        close_btn.clicked.connect(self.on_close)
+        
+        self.layout().addWidget(close_btn)
+    
+    def on_close(self):
+        self.close_signal.emit()
+        
+    def plot(self, item):
+        print("plot!", item)