PyQt/QFlowLayout/Lib/flowlayout.py
2021-07-13 14:52:26 +08:00

160 lines
5.3 KiB
Python

#!/usr/bin/env python
#############################################################################
##
# Copyright (C) 2013 Riverbank Computing Limited.
# Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
# All rights reserved.
##
# This file is part of the examples of PyQt.
##
# $QT_BEGIN_LICENSE:BSD$
# You may use this file under the terms of the BSD license as follows:
##
# "Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
# the names of its contributors may be used to endorse or promote
# products derived from this software without specific prior written
# permission.
##
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
# $QT_END_LICENSE$
##
#############################################################################
from PyQt5.QtCore import QPoint, QRect, QSize, Qt
from PyQt5.QtWidgets import (QApplication, QLayout, QPushButton, QSizePolicy,
QWidget)
class Window(QWidget):
def __init__(self):
super(Window, self).__init__()
flowLayout = FlowLayout()
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.setLayout(flowLayout)
self.setWindowTitle("Flow Layout")
class FlowLayout(QLayout):
def __init__(self, parent=None, margin=0, spacing=-1):
super(FlowLayout, self).__init__(parent)
if parent is not None:
self.setContentsMargins(margin, margin, margin, margin)
self.setSpacing(spacing)
self.itemList = []
def __del__(self):
item = self.takeAt(0)
while item:
item = self.takeAt(0)
def addItem(self, item):
self.itemList.append(item)
def count(self):
return len(self.itemList)
def itemAt(self, index):
if index >= 0 and index < len(self.itemList):
return self.itemList[index]
return None
def takeAt(self, index):
if index >= 0 and index < len(self.itemList):
return self.itemList.pop(index)
return None
def expandingDirections(self):
return Qt.Orientations(Qt.Orientation(0))
def hasHeightForWidth(self):
return True
def heightForWidth(self, width):
height = self.doLayout(QRect(0, 0, width, 0), True)
return height
def setGeometry(self, rect):
super(FlowLayout, self).setGeometry(rect)
self.doLayout(rect, False)
def sizeHint(self):
return self.minimumSize()
def minimumSize(self):
size = QSize()
for item in self.itemList:
size = size.expandedTo(item.minimumSize())
margin, _, _, _ = self.getContentsMargins()
size += QSize(2 * margin, 2 * margin)
return size
def doLayout(self, rect, testOnly):
x = rect.x()
y = rect.y()
lineHeight = 0
for item in self.itemList:
wid = item.widget()
spaceX = self.spacing() + wid.style().layoutSpacing(QSizePolicy.PushButton,
QSizePolicy.PushButton, Qt.Horizontal)
spaceY = self.spacing() + wid.style().layoutSpacing(QSizePolicy.PushButton,
QSizePolicy.PushButton, Qt.Vertical)
nextX = x + item.sizeHint().width() + spaceX
if nextX - spaceX > rect.right() and lineHeight > 0:
x = rect.x()
y = y + lineHeight + spaceY
nextX = x + item.sizeHint().width() + spaceX
lineHeight = 0
if not testOnly:
item.setGeometry(QRect(QPoint(x, y), item.sizeHint()))
x = nextX
lineHeight = max(lineHeight, item.sizeHint().height())
return y + lineHeight - rect.y()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
mainWin = Window()
mainWin.show()
sys.exit(app.exec_())