python流式计算框架_pythonGUI框架pyqt5如何对图片进行流式布局（瀑布流flowlayout）...

流式布局

流式布局&＃xff0c;也叫做瀑布流布局&＃xff0c;是网页中经常使用的一种页面布局方式&＃xff0c;它的原理就是将高度固定&＃xff0c;然后图片的宽度自适应&＃xff0c;这样加载出来的图片看起来就像瀑布一样整齐的水流淌下来。

pyqt流式布局

那么在pyqt5中我们怎么使用流式布局呢&＃xff1f;pyqt没有这个控件&＃xff0c;需要我们自己去封装&＃xff0c;下面是流式布局的封装代码。

class FlowLayout(QLayout):

def __init__(self, parent&＃61;None, margin&＃61;0, spacing&＃61;-1):

super(FlowLayout, self).__init__(parent)

if parent is not None:

self.setContentsMargins(margin, margin, margin, margin)

self.setSpacing(spacing)

self.itemList &＃61; []

def __del__(self):

item &＃61; self.takeAt(0)

while item:

item &＃61; self.takeAt(0)

def addItem(self, item):

self.itemList.append(item)

def count(self):

return len(self.itemList)

def itemAt(self, index):

if index >&＃61; 0 and index

return self.itemList[index]

return None

def takeAt(self, index):

if index >&＃61; 0 and index

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 &＃61; 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 &＃61; QSize()

for item in self.itemList:

size &＃61; size.expandedTo(item.minimumSize())

margin, _, _, _ &＃61; self.getContentsMargins()

size &＃43;&＃61; QSize(2 * margin, 2 * margin)

return size

def doLayout(self, rect, testOnly):

x &＃61; rect.x()

y &＃61; rect.y()

lineHeight &＃61; 0

for item in self.itemList:

wid &＃61; item.widget()

spaceX &＃61; self.spacing() &＃43; wid.style().layoutSpacing(QSizePolicy.PushButton,

QSizePolicy.PushButton, Qt.Horizontal)

spaceY &＃61; self.spacing() &＃43; wid.style().layoutSpacing(QSizePolicy.PushButton,

QSizePolicy.PushButton, Qt.Vertical)

nextX &＃61; x &＃43; item.sizeHint().width() &＃43; spaceX

if nextX - spaceX > rect.right() and lineHeight > 0:

x &＃61; rect.x()

y &＃61; y &＃43; lineHeight &＃43; spaceY

nextX &＃61; x &＃43; item.sizeHint().width() &＃43; spaceX

lineHeight &＃61; 0

if not testOnly:

item.setGeometry(QRect(QPoint(x, y), item.sizeHint()))

x &＃61; nextX

lineHeight &＃61; max(lineHeight, item.sizeHint().height())

return y &＃43; lineHeight - rect.y()

封装好的流式布局类&＃xff0c;我们只要传入相应的layout之后&＃xff0c;他就会自动计算页面的元素&＃xff0c;适应页面的宽度。

下面是我们写的一个瀑布流显示图片的代码:

from PyQt5.QtCore import QPoint, QRect, QSize, Qt

import os

from PyQt5 import QtCore, QtGui, QtWidgets

from PyQt5.QtWidgets import (

QApplication, QLayout, QPushButton, QSizePolicy, QWidget, QGridLayout)

class Window(QWidget):

def __init__(self):

self.imageheight &＃61; 100

super(Window, self).__init__()

self.resize(400, 300)

flowLayout &＃61; FlowLayout()

highlight_dir &＃61; "./"

self.files_it &＃61; iter([os.path.join(highlight_dir, file)

for file in os.listdir(highlight_dir)])

print()

for file in iter(self.files_it):

layout &＃61; QGridLayout()

pixmap &＃61; QtGui.QPixmap(file)

if not pixmap.isNull():

autoWidth &＃61; pixmap.width()*self.imageheight/pixmap.height()

label &＃61; QtWidgets.QLabel(pixmap&＃61;pixmap)

label.setScaledContents(True)

label.setFixedHeight(self.imageheight)

print(autoWidth)

label.setFixedWidth(autoWidth)

#label.setFixedSize(100, 50)

layout.addWidget(label)

widget &＃61; QWidget()

widget.setLayout(layout)

flowLayout.addWidget(widget)

self.setLayout(flowLayout)

self.setWindowTitle("Flow Layout")

class FlowLayout(QLayout):

def __init__(self, parent&＃61;None, margin&＃61;0, spacing&＃61;-1):

super(FlowLayout, self).__init__(parent)

if parent is not None:

self.setContentsMargins(margin, margin, margin, margin)

self.setSpacing(spacing)

self.itemList &＃61; []

def __del__(self):

item &＃61; self.takeAt(0)

while item:

item &＃61; self.takeAt(0)

def addItem(self, item):

self.itemList.append(item)

def count(self):

return len(self.itemList)

def itemAt(self, index):

if index >&＃61; 0 and index

return self.itemList[index]

return None

def takeAt(self, index):

if index >&＃61; 0 and index

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 &＃61; 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 &＃61; QSize()

for item in self.itemList:

size &＃61; size.expandedTo(item.minimumSize())

margin, _, _, _ &＃61; self.getContentsMargins()

size &＃43;&＃61; QSize(2 * margin, 2 * margin)

return size

def doLayout(self, rect, testOnly):

x &＃61; rect.x()

y &＃61; rect.y()

lineHeight &＃61; 0

for item in self.itemList:

wid &＃61; item.widget()

spaceX &＃61; self.spacing() &＃43; wid.style().layoutSpacing(QSizePolicy.PushButton,

QSizePolicy.PushButton, Qt.Horizontal)

spaceY &＃61; self.spacing() &＃43; wid.style().layoutSpacing(QSizePolicy.PushButton,

QSizePolicy.PushButton, Qt.Vertical)

nextX &＃61; x &＃43; item.sizeHint().width() &＃43; spaceX

if nextX - spaceX > rect.right() and lineHeight > 0:

x &＃61; rect.x()

y &＃61; y &＃43; lineHeight &＃43; spaceY

nextX &＃61; x &＃43; item.sizeHint().width() &＃43; spaceX

lineHeight &＃61; 0

if not testOnly:

item.setGeometry(QRect(QPoint(x, y), item.sizeHint()))

x &＃61; nextX

lineHeight &＃61; max(lineHeight, item.sizeHint().height())

return y &＃43; lineHeight - rect.y()

if __name__ &＃61;&＃61; &＃39;__main__&＃39;:

import sys

app &＃61; QApplication(sys.argv)

mainWin &＃61; Window()

mainWin.show()

sys.exit(app.exec_())