Qt5 mvc: revealing the secrets of data visualization

MVC Mode principle

Every program has its principle , We learn through their principles , To understand their work direction , It will make our study very simple .

Uncover the data hierarchy order

1. Create format layout
2. Call the visualization function
3. Build character list model
4. Define list source data columns
5. Add the data source list to the list model
6. Add the list model to the visualization function （ Visual Click to send signal – Activate the message box ）
7. Message box slot function , It is equivalent to the functional interaction of column number data , Complete data message function debugging
8. Add visualization to the layout , It is equivalent to placing it inside the window
9. Activate visual layout , It is equivalent to uncovering the red cloth on the plaque of data , Officially publicize the opening to the public .

Message slot function
def clicked(self,item):
QMessageBox.information()— Message box
Parameters 1： Inherited parent class self
Parameters 2：QListView— Trigger inherited from QListView
Parameters 3： Box information , Signal list index item.row()
remarks ：
item— Is the content of the list
.row()— Is to call the display row index of the current content （0,1,2…）

Program source code

from PyQt5.Qt import *
import sys
app = QApplication([])
class ListView(QWidget):
    def __init__(self,parent=None):
        super(ListView,self).__init__(parent)
        self.setWindowTitle('QListView  Example ')
        self.resize(300,270)
        layout = QVBoxLayout()
        listview = QListView()
        listmodel = QStringListModel()# A list of characters : Display models for lists 
        self.list = [' list 1',' list 2',' list 3']
        listmodel.setStringList(self.list)
        listview.setModel(listmodel)
        listview.clicked.connect(self.clicked) # Launch a item.row() Index data to self.clicked
        layout.addWidget(listview)
        self.setLayout(layout) # Layout effective statement , Must be complete , Otherwise, the added visualization template cannot be displayed 

    # Click to pop up the message box , Clicking on each list item will have a value stored in the slot function item in ,item.row() Method will display the index data of the corresponding item 
    def clicked(self,item):
        QMessageBox.information(self,'QListView',' You chose '+self.list[item.row()])

win = ListView()
win.show()
sys.exit(app.exec_())