Pyqt5 controls qpixmap, qlineedit qsplitter, qcombobox

QPixmap

• QPixmap Is a control for processing images . Is the optimized display image on the screen . In our code example , We will use QPixmap The window displays an image .

# -*- coding: utf-8 -*-

""" PyQt5 tutorial In this example, we dispay an image on the window. author: py40.com last edited: 2017 year 3 month  """
import sys
from PyQt5.QtWidgets import (QWidget, QHBoxLayout,
                             QLabel, QApplication)
from PyQt5.QtGui import QPixmap


class Example(QWidget):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        hbox = QHBoxLayout(self)
        pixmap = QPixmap("icon.png")

        lbl = QLabel(self)
        lbl.setPixmap(pixmap)

        hbox.addWidget(lbl)
        self.setLayout(hbox)

        self.move(300, 200)
        self.setWindowTitle('Red Rock')
        self.show()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

• Show a picture on the window

pixmap = QPixmap("icon.png")

• Create a QPixmap object , It takes the passed in file name as a parameter .

lbl = QLabel(self)
lbl.setPixmap(pixmap)

• This will make us pixmap Put it in QLabel Control .

The text box QLineEdit

• QLineEdit Is a control for entering or editing single line text . It also has undo redo 、 Cut, copy and drag .

# -*- coding: utf-8 -*-

""" PyQt5 tutorial This example shows text which is entered in a QLineEdit in a QLabel widget. author: py40.com last edited: 2017 year 3 month  """
import sys
from PyQt5.QtWidgets import (QWidget, QLabel,
                             QLineEdit, QApplication)


class Example(QWidget):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        self.lbl = QLabel(self)
        qle = QLineEdit(self)

        qle.move(60, 100)
        self.lbl.move(60, 40)

        qle.textChanged[str].connect(self.onChanged)

        self.setGeometry(300, 300, 280, 170)
        self.setWindowTitle('QLineEdit')
        self.show()

    def onChanged(self, text):
        self.lbl.setText(text)
        self.lbl.adjustSize()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

• The example shows a QLineEdit With a QLabel. We are QLineEdit The text entered in will be displayed in real time QLabel Control .

qle = QLineEdit(self)

• establish QLineEdit

qle.textChanged[str].connect(self.onChanged)

• When the content of the text box changes , Would call onChanged Method

def onChanged(self, text):
    
    self.lbl.setText(text)
    self.lbl.adjustSize() 

• stay onChanged() In the method, we will QLabel Control to the input . By calling adjustSize() Methods will QLabel Control is resized to the length of the text .

QSplitter

• adopt QSplitter, The user can drag the border of the child control to adjust the size of the child control . In the following example , We show three by two QSplitter The organization's QFrame Control .

# -*- coding: utf-8 -*-

""" PyQt5 tutorial This example shows how to use QSplitter widget. author: py40.com last edited: 2017 year 3 month  """
import sys
from PyQt5.QtWidgets import (QWidget, QHBoxLayout, QFrame,
                             QSplitter, QStyleFactory, QApplication)
from PyQt5.QtCore import Qt


class Example(QWidget):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        hbox = QHBoxLayout(self)

        topleft = QFrame(self)
        topleft.setFrameShape(QFrame.StyledPanel)

        topright = QFrame(self)
        topright.setFrameShape(QFrame.StyledPanel)

        bottom = QFrame(self)
        bottom.setFrameShape(QFrame.StyledPanel)

        splitter1 = QSplitter(Qt.Horizontal)
        splitter1.addWidget(topleft)
        splitter1.addWidget(topright)

        splitter2 = QSplitter(Qt.Vertical)
        splitter2.addWidget(splitter1)
        splitter2.addWidget(bottom)

        hbox.addWidget(splitter2)
        self.setLayout(hbox)

        self.setGeometry(300, 300, 300, 200)
        self.setWindowTitle('QSplitter')
        self.show()

    def onChanged(self, text):
        self.lbl.setText(text)
        self.lbl.adjustSize()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

• In the example, we created three QFrame With two QSplitter. Note these in some topics QSplitter May not be visible .

topleft = QFrame(self)
topleft.setFrameShape(QFrame.StyledPanel)

• We use a style framework in order to see QFrame Boundaries between widgets .

splitter1 = QSplitter(Qt.Horizontal)
splitter1.addWidget(topleft)
splitter1.addWidget(topright)

• We create a QSplitter Widget and add two frames .

splitter2 = QSplitter(Qt.Vertical)
splitter2.addWidget(splitter1)

• We can also put QSplitter Add to another QSplitter Control .

The drop-down list QComboBox

• QComboBox Is a control that allows the user to select from a drop-down list .

# -*- coding: utf-8 -*-

""" PyQt5 tutorial This example shows how to use a QComboBox widget. author: py40.com last edited: 2017 year 3 month  """
import sys
from PyQt5.QtWidgets import (QWidget, QLabel,
                             QComboBox, QApplication)


class Example(QWidget):
    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):
        self.lbl = QLabel("Ubuntu", self)

        combo = QComboBox(self)
        combo.addItem("Ubuntu")
        combo.addItem("Mandriva")
        combo.addItem("Fedora")
        combo.addItem("Arch")
        combo.addItem("Gentoo")

        combo.move(50, 50)
        self.lbl.move(50, 150)

        combo.activated[str].connect(self.onActivated)

        self.setGeometry(300, 300, 300, 200)
        self.setWindowTitle('QComboBox')
        self.show()

    def onActivated(self, text):
        self.lbl.setText(text)
        self.lbl.adjustSize()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

• The example shows a QComboBox With a QLabel,QComboBox Control has 5 An option (Linux Several release names of the system ).QLabel Control displays QComboBox An option selected in .

combo = QComboBox(self)
combo.addItem("Ubuntu")
combo.addItem("Mandriva")
combo.addItem("Fedora")
combo.addItem("Arch")
combo.addItem("Gentoo")

• Created a with five options QComboBox

combo.activated[str].connect(self.onActivated) 

• When an entry is selected, it calls onActivated() Method .

def onActivated(self, text):
  
    self.lbl.setText(text)
    self.lbl.adjustSize() 

• In the method we will QLabel The content of the control is set to the selected item , Then adjust its size .