1 2############################################################################ 3## 4## Copyright (C) 2013 Riverbank Computing Limited. 5## Copyright (C) 2020 The Qt Company Ltd. 6## Contact: http://www.qt.io/licensing/ 7## 8## This file is part of the Qt for Python examples of the Qt Toolkit. 9## 10## $QT_BEGIN_LICENSE:BSD$ 11## You may use this file under the terms of the BSD license as follows: 12## 13## "Redistribution and use in source and binary forms, with or without 14## modification, are permitted provided that the following conditions are 15## met: 16## * Redistributions of source code must retain the above copyright 17## notice, this list of conditions and the following disclaimer. 18## * Redistributions in binary form must reproduce the above copyright 19## notice, this list of conditions and the following disclaimer in 20## the documentation and/or other materials provided with the 21## distribution. 22## * Neither the name of The Qt Company Ltd nor the names of its 23## contributors may be used to endorse or promote products derived 24## from this software without specific prior written permission. 25## 26## 27## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 30## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 31## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 32## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 33## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 37## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." 38## 39## $QT_END_LICENSE$ 40## 41############################################################################# 42 43"""PySide2 port of the widgets/layouts/flowlayout example from Qt v5.x""" 44 45import sys 46from PySide2.QtCore import Qt, QMargins, QPoint, QRect, QSize 47from PySide2.QtWidgets import (QApplication, QLayout, QPushButton, 48 QSizePolicy, QWidget) 49 50 51class Window(QWidget): 52 def __init__(self): 53 super(Window, self).__init__() 54 55 flowLayout = FlowLayout(self) 56 flowLayout.addWidget(QPushButton("Short")) 57 flowLayout.addWidget(QPushButton("Longer")) 58 flowLayout.addWidget(QPushButton("Different text")) 59 flowLayout.addWidget(QPushButton("More text")) 60 flowLayout.addWidget(QPushButton("Even longer button text")) 61 62 self.setWindowTitle("Flow Layout") 63 64 65class FlowLayout(QLayout): 66 def __init__(self, parent=None): 67 super(FlowLayout, self).__init__(parent) 68 69 if parent is not None: 70 self.setContentsMargins(QMargins(0, 0, 0, 0)) 71 72 self._item_list = [] 73 74 def __del__(self): 75 item = self.takeAt(0) 76 while item: 77 item = self.takeAt(0) 78 79 def addItem(self, item): 80 self._item_list.append(item) 81 82 def count(self): 83 return len(self._item_list) 84 85 def itemAt(self, index): 86 if index >= 0 and index < len(self._item_list): 87 return self._item_list[index] 88 89 return None 90 91 def takeAt(self, index): 92 if index >= 0 and index < len(self._item_list): 93 return self._item_list.pop(index) 94 95 return None 96 97 def expandingDirections(self): 98 return Qt.Orientations(Qt.Orientation(0)) 99 100 def hasHeightForWidth(self): 101 return True 102 103 def heightForWidth(self, width): 104 height = self._do_layout(QRect(0, 0, width, 0), True) 105 return height 106 107 def setGeometry(self, rect): 108 super(FlowLayout, self).setGeometry(rect) 109 self._do_layout(rect, False) 110 111 def sizeHint(self): 112 return self.minimumSize() 113 114 def minimumSize(self): 115 size = QSize() 116 117 for item in self._item_list: 118 size = size.expandedTo(item.minimumSize()) 119 120 size += QSize(2 * self.contentsMargins().top(), 121 2 * self.contentsMargins().top()) 122 return size 123 124 def _do_layout(self, rect, test_only): 125 x = rect.x() 126 y = rect.y() 127 line_height = 0 128 spacing = self.spacing() 129 130 for item in self._item_list: 131 style = item.widget().style() 132 layout_spacing_x = style.layoutSpacing(QSizePolicy.PushButton, 133 QSizePolicy.PushButton, 134 Qt.Horizontal) 135 layout_spacing_y = style.layoutSpacing(QSizePolicy.PushButton, 136 QSizePolicy.PushButton, 137 Qt.Vertical) 138 space_x = spacing + layout_spacing_x 139 space_y = spacing + layout_spacing_y 140 next_x = x + item.sizeHint().width() + space_x 141 if next_x - space_x > rect.right() and line_height > 0: 142 x = rect.x() 143 y = y + line_height + space_y 144 next_x = x + item.sizeHint().width() + space_x 145 line_height = 0 146 147 if not test_only: 148 item.setGeometry(QRect(QPoint(x, y), item.sizeHint())) 149 150 x = next_x 151 line_height = max(line_height, item.sizeHint().height()) 152 153 return y + line_height - rect.y() 154 155 156if __name__ == '__main__': 157 app = QApplication(sys.argv) 158 mainWin = Window() 159 mainWin.show() 160 sys.exit(app.exec_()) 161