Add NoBorderScrollArea, example and tests (#155)

CHANGELOG.md

@@ -1,5 +1,6 @@
-# Version x.x.x
-- Edit next and prev in UIMultiStepWidget #151
+# Version 1.0.1
+- Add NoBorderScrollArea, example and tests (#155)
+- Edit next and prev in UIMultiStepWidget (#151)
 - Remove question mark from form dialog (#150)
 
 # Version 1.0.0

eqt/ui/NoBorderScrollArea.py

@@ -0,0 +1,40 @@
+import re
+
+import qdarkstyle
+from PySide2.QtWidgets import QPushButton, QScrollArea, QWidget
+
+
+class NoBorderScrollArea(QScrollArea):
+    def __init__(self, widget, parent=None):
+        """Creates an instance of a QScrollArea and sets its border to none.
+        Sets its widget to resizable. Due to a bug in `qdarkstyle`, the PushButtons in the
+        widget do not inherit the right style. The init applies `qdarkstyle` to all the buttons
+        present in the widget when the object is created. Any button added to the widget after the
+        init is invoked will not be styled as expected. In this case, the method
+        `apply_qdarkstyle_to_buttons` would need to be invoked by the user after the object is
+        instanced."""
+        super().__init__(parent)
+        self.setStyleSheet("QScrollArea { border: none; }")
+        self.setWidgetResizable(True)
+        self.setWidget(widget)
+        self.apply_qdarkstyle_to_buttons(widget)
+
+    def apply_qdarkstyle_to_buttons(self, widget):
+        """Applies the qdarkstyle to all the buttons in the widget explicitly.
+        This ensures that the style is consistent with the rest of the app."""
+        if isinstance(widget, QPushButton):
+
+            button_style = self._extract_qdarkstyle_button_style()
+            widget.setStyleSheet(button_style)
+        for child in widget.findChildren(QWidget):
+            self.apply_qdarkstyle_to_buttons(child)
+
+    def _extract_qdarkstyle_button_style(self):
+        """Returns the QPushButton styles from qdarkstyle, including the different
+        button styles."""
+        style = qdarkstyle.load_stylesheet(qt_api='pyside2')
+        pattern = re.compile(r"(QPushButton\s*{[^}]*}|QPushButton\s*:[^}]*{[^}]*})", re.DOTALL)
+        matches = pattern.findall(style)
+        if matches:
+            return ''.join(matches)
+        return ""

examples/NoBorderScrollArea_example.py

@@ -0,0 +1,39 @@
+import sys
+
+from PySide2 import QtWidgets
+from PySide2.QtWidgets import QPushButton
+
+from eqt.ui.NoBorderScrollArea import NoBorderScrollArea
+
+
+class MainUI(QtWidgets.QMainWindow):
+    def __init__(self, parent=None):
+        """Any button added after the `NoBorderScrollArea` is instanced will not be styled as
+        expected, due to the bug in `qdarkstyle`. The method `apply_qdarkstyle_to_buttons` needs
+        to be invoked."""
+        QtWidgets.QMainWindow.__init__(self, parent)
+
+        layout = QtWidgets.QVBoxLayout()
+        widg = QtWidgets.QWidget()
+        widg.setLayout(layout)
+
+        layout.addWidget(QPushButton("Test"))
+        layout.addWidget(QPushButton("Test2"))
+
+        self.scroll_area_widget = NoBorderScrollArea(widg)
+
+        layout.addWidget(QPushButton("Test3"))
+        self.scroll_area_widget.apply_qdarkstyle_to_buttons(widg)
+        layout.addWidget(QPushButton("Test4"))
+
+        self.setCentralWidget(self.scroll_area_widget)
+
+        self.show()
+
+
+if __name__ == "__main__":
+    app = QtWidgets.QApplication(sys.argv)
+
+    window = MainUI()
+
+    sys.exit(app.exec_())

test/test_NoBorderScrollArea.py

@@ -0,0 +1,26 @@
+import unittest
+
+from PySide2.QtWidgets import QHBoxLayout, QPushButton, QWidget
+
+from eqt.ui.NoBorderScrollArea import NoBorderScrollArea
+
+from . import is_ci, skip
+
+if is_ci:
+    skip("Running in CI (no GUI)", allow_module_level=True)
+
+
+class TestNoBorderScrollArea(unittest.TestCase):
+    def setUp(self):
+        '''Initialises a NoBorderScrollArea widget and adds it to a layout.'''
+        self.main_widget = QWidget()
+        self.layout = QHBoxLayout(self.main_widget)
+        self.scroll_area_widget = NoBorderScrollArea(QPushButton())
+        self.layout.addWidget(self.scroll_area_widget)
+
+    def test_scroll_area_creation(self):
+        '''
+        Tests the init method of the NoBorderScrollArea class.
+        '''
+        self.assertIsNotNone(self.scroll_area_widget,
+                             "NoBorderScrollArea widget should be created")