TR update

Author: lpozo

pyqt-calculator-tutorial/examples/signals_slots.py

@@ -1,6 +1,6 @@
 # Filename: signals_slots.py
 
-"""Signals and Slots example."""
+"""Signals and slots example."""
 
 import sys
 
@@ -13,7 +13,10 @@
 
 def greeting():
     """Slot function."""
-    msg.setText("Hello World!")
+    if msg.text():
+        msg.setText("")
+    else:
+        msg.setText("Hello World!")
 
 
 app = QApplication(sys.argv)

pyqt-calculator-tutorial/examples/signals_slots_partial.py

@@ -0,0 +1,36 @@
+# Filename: signals_slots_partial.py
+
+"""Signals and slots example."""
+
+import sys
+import functools
+
+from PyQt5.QtWidgets import QApplication
+from PyQt5.QtWidgets import QWidget
+from PyQt5.QtWidgets import QPushButton
+from PyQt5.QtWidgets import QLabel
+from PyQt5.QtWidgets import QVBoxLayout
+
+
+def greeting(who):
+    """Slot function."""
+    if msg.text():
+        msg.setText("")
+    else:
+        msg.setText(f"Hello {who}")
+
+
+app = QApplication(sys.argv)
+window = QWidget()
+window.setWindowTitle("Signals, and Slots")
+layout = QVBoxLayout()
+
+btn = QPushButton("Greet")
+btn.clicked.connect(functools.partial(greeting, "World!"))
+
+layout.addWidget(btn)
+msg = QLabel("")
+layout.addWidget(msg)
+window.setLayout(layout)
+window.show()
+sys.exit(app.exec_())

pyqt-calculator-tutorial/pycalc/pycalc.py

@@ -41,7 +41,7 @@ def __init__(self):
         # Set some main window's properties
         self.setWindowTitle("PyCalc")
         self.setFixedSize(235, 235)
-        # Create and set the central widget and the general layout
+        # Set the central widget and the general layout
         self.generalLayout = QVBoxLayout()
         self._centralWidget = QWidget(self)
         self.setCentralWidget(self._centralWidget)
@@ -164,7 +164,7 @@ def main():
     # Show the calculator's GUI
     view = PyCalcUi()
     view.show()
-    # Create an instance of the model and the controller
+    # Create instances of the model and the controller
     model = evaluateExpression
     PyCalcCtrl(model=model, view=view)
     # Execute calculator's main loop