Qt之监听窗口改变事件（最小化、最大化、还原）

#include "mainwindow.h" #include "ui_mainwindow.h" MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) , ui(new Ui::MainWindow) { ui->setupUi(this); setWindowTitle(QStringLiteral("Qt之监听窗口改变事件（最小化、最大化、还原）")); } MainWindow::~MainWindow() { delete ui; } void MainWindow::changeEvent(QEvent *event) { if(QEvent::WindowStateChange == event->type()) { QWindowStateChangeEvent * stateEvent = dynamic_cast<QWindowStateChangeEvent*>(event); if(Q_NULLPTR != stateEvent) { Qt::WindowStates x = stateEvent->oldState(); ui->textEdit->append(QString("oldState %1").arg(x)); if(Qt::WindowMinimized == stateEvent->oldState()) { ui->textEdit->append(QString("oldState %1").arg(x)); } else if(Qt::WindowMaximized == stateEvent->oldState()) { ui->textEdit->append(QString("oldState %1").arg(x)); } } } } void MainWindow::on_pushButton_clicked() { this->showMinimized(); } void MainWindow::on_pushButton_2_clicked() { this->showMaximized(); } void MainWindow::on_pushButton_3_clicked() { this->showNormal(); }