Polish the flow layout example

- Import by class
- Rename variables and functions,
- Fix long lines

Task-number: PYSIDE-841
Change-Id: Icb4615e15d0b54d3e2893ffa7981ced7b7526952
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

1 files changed, 54 insertions, 49 deletions

diff --git a/examples/widgets/layouts/flowlayout.py b/examples/widgets/layouts/flowlayout.py
index f63fd5549..970d5ac07 100644
--- a/examples/widgets/layouts/flowlayout.py
+++ b/examples/widgets/layouts/flowlayout.py
@@ -2,7 +2,7 @@
 ############################################################################
 ##
 ## Copyright (C) 2013 Riverbank Computing Limited.
-## Copyright (C) 2016 The Qt Company Ltd.
+## Copyright (C) 2020 The Qt Company Ltd.
 ## Contact: http://www.qt.io/licensing/
 ##
 ## This file is part of the Qt for Python examples of the Qt Toolkit.
@@ -42,34 +42,34 @@
 
 """PySide2 port of the widgets/layouts/flowlayout example from Qt v5.x"""
 
-from PySide2 import QtCore, QtWidgets
+import sys
+from PySide2.QtCore import Qt, QMargins, QPoint, QRect, QSize
+from PySide2.QtWidgets import (QApplication, QLayout, QPushButton,
+                               QSizePolicy, QWidget)
 
 
-class Window(QtWidgets.QWidget):
+class Window(QWidget):
     def __init__(self):
         super(Window, self).__init__()
 
-        flowLayout = FlowLayout()
-        flowLayout.addWidget(QtWidgets.QPushButton("Short"))
-        flowLayout.addWidget(QtWidgets.QPushButton("Longer"))
-        flowLayout.addWidget(QtWidgets.QPushButton("Different text"))
-        flowLayout.addWidget(QtWidgets.QPushButton("More text"))
-        flowLayout.addWidget(QtWidgets.QPushButton("Even longer button text"))
-        self.setLayout(flowLayout)
+        flowLayout = FlowLayout(self)
+        flowLayout.addWidget(QPushButton("Short"))
+        flowLayout.addWidget(QPushButton("Longer"))
+        flowLayout.addWidget(QPushButton("Different text"))
+        flowLayout.addWidget(QPushButton("More text"))
+        flowLayout.addWidget(QPushButton("Even longer button text"))
 
         self.setWindowTitle("Flow Layout")
 
 
-class FlowLayout(QtWidgets.QLayout):
-    def __init__(self, parent=None, margin=0, spacing=-1):
+class FlowLayout(QLayout):
+    def __init__(self, parent=None):
         super(FlowLayout, self).__init__(parent)
 
         if parent is not None:
-            self.setMargin(margin)
+            self.setContentsMargins(QMargins(0, 0, 0, 0))
 
-        self.setSpacing(spacing)
-
-        self.itemList = []
+        self._item_list = []
 
     def __del__(self):
         item = self.takeAt(0)
@@ -77,79 +77,84 @@ class FlowLayout(QtWidgets.QLayout):
             item = self.takeAt(0)
 
     def addItem(self, item):
-        self.itemList.append(item)
+        self._item_list.append(item)
 
     def count(self):
-        return len(self.itemList)
+        return len(self._item_list)
 
     def itemAt(self, index):
-        if index >= 0 and index < len(self.itemList):
-            return self.itemList[index]
+        if index >= 0 and index < len(self._item_list):
+            return self._item_list[index]
 
         return None
 
     def takeAt(self, index):
-        if index >= 0 and index < len(self.itemList):
-            return self.itemList.pop(index)
+        if index >= 0 and index < len(self._item_list):
+            return self._item_list.pop(index)
 
         return None
 
     def expandingDirections(self):
-        return QtCore.Qt.Orientations(QtCore.Qt.Orientation(0))
+        return Qt.Orientations(Qt.Orientation(0))
 
     def hasHeightForWidth(self):
         return True
 
     def heightForWidth(self, width):
-        height = self.doLayout(QtCore.QRect(0, 0, width, 0), True)
+        height = self._do_layout(QRect(0, 0, width, 0), True)
         return height
 
     def setGeometry(self, rect):
         super(FlowLayout, self).setGeometry(rect)
-        self.doLayout(rect, False)
+        self._do_layout(rect, False)
 
     def sizeHint(self):
         return self.minimumSize()
 
     def minimumSize(self):
-        size = QtCore.QSize()
+        size = QSize()
 
-        for item in self.itemList:
+        for item in self._item_list:
             size = size.expandedTo(item.minimumSize())
 
-        size += QtCore.QSize(2 * self.contentsMargins().top(), 2 * self.contentsMargins().top())
+        size += QSize(2 * self.contentsMargins().top(),
+                      2 * self.contentsMargins().top())
         return size
 
-    def doLayout(self, rect, testOnly):
+    def _do_layout(self, rect, test_only):
         x = rect.x()
         y = rect.y()
-        lineHeight = 0
-
-        for item in self.itemList:
-            wid = item.widget()
-            spaceX = self.spacing() + wid.style().layoutSpacing(QtWidgets.QSizePolicy.PushButton, QtWidgets.QSizePolicy.PushButton, QtCore.Qt.Horizontal)
-            spaceY = self.spacing() + wid.style().layoutSpacing(QtWidgets.QSizePolicy.PushButton, QtWidgets.QSizePolicy.PushButton, QtCore.Qt.Vertical)
-            nextX = x + item.sizeHint().width() + spaceX
-            if nextX - spaceX > rect.right() and lineHeight > 0:
+        line_height = 0
+        spacing = self.spacing()
+
+        for item in self._item_list:
+            style = item.widget().style()
+            layout_spacing_x = style.layoutSpacing(QSizePolicy.PushButton,
+                                                   QSizePolicy.PushButton,
+                                                   Qt.Horizontal)
+            layout_spacing_y = style.layoutSpacing(QSizePolicy.PushButton,
+                                                   QSizePolicy.PushButton,
+                                                   Qt.Vertical)
+            space_x = spacing + layout_spacing_x
+            space_y = spacing + layout_spacing_y
+            next_x = x + item.sizeHint().width() + space_x
+            if next_x - space_x > rect.right() and line_height > 0:
                 x = rect.x()
-                y = y + lineHeight + spaceY
-                nextX = x + item.sizeHint().width() + spaceX
-                lineHeight = 0
+                y = y + line_height + space_y
+                next_x = x + item.sizeHint().width() + space_x
+                line_height = 0
 
-            if not testOnly:
-                item.setGeometry(QtCore.QRect(QtCore.QPoint(x, y), item.sizeHint()))
+            if not test_only:
+                item.setGeometry(QRect(QPoint(x, y), item.sizeHint()))
 
-            x = nextX
-            lineHeight = max(lineHeight, item.sizeHint().height())
+            x = next_x
+            line_height = max(line_height, item.sizeHint().height())
 
-        return y + lineHeight - rect.y()
+        return y + line_height - rect.y()
 
 
 if __name__ == '__main__':
-
-    import sys
-
-    app = QtWidgets.QApplication(sys.argv)
+    app = QApplication(sys.argv)
     mainWin = Window()
     mainWin.show()
     sys.exit(app.exec_())