1.浮动窗口

代码：

    //制作核心控件：文本编辑框QTextEdit* pTextEdit=new QTextEdit;//制作浮动控件connect(pMenu1,&QMenu::triggered,[=](QAction* pAction){qDebug()<<pAction->text()<<endl;if(pAction->text()=="浮动控件"){QDockWidget* pDockWidget=new QDockWidget;QTextEdit* pTextEdit2=new QTextEdit;pDockWidget->setWidget(pTextEdit2);//添加浮动控件this->addDockWidget(Qt::RightDockWidgetArea,pDockWidget);}else if(pAction->text()=="核心控件"){this->setCentralWidget(pTextEdit);}});

QTextEdit为文本编辑框

QDockWidget为浮动控件，其中放置了一个QTextEdit文本编辑框

2.模态对话框，非模态对话框，消息框，文件对话框

1.模态对话框：必须处理对话框才可以切换回主界面。

2.非模态对话框：与上相反

3.消息框:也是模态对话框

4.文件对话框：弹出找文件

#include "mainwindow.h"
#include <QMenuBar>
#include <QMenu>
#include <QAction>
#include <QDebug>
#include <QDialog>
#include <QMessageBox>
#include <QFileDialog>
MainWindow::MainWindow(QWidget *parent): QMainWindow(parent)
{//创建窗口，交互按键setWindowTitle("对话框学习");resize(400,400);QMenuBar* pMenuBar=menuBar();QMenu* pMenu=new QMenu();pMenu->setTitle("对话框");pMenuBar->addMenu(pMenu);QAction* pAction1=new QAction;pAction1->setText("模态对话框");QAction* pAction2=new QAction;pAction2->setText("非模态对话框");QAction* pAction3=new QAction;pAction3->setText("消息框");QAction* pAction4=new QAction;pAction4->setText("文件对话框");pMenu->addAction(pAction1);pMenu->addAction(pAction2);pMenu->addAction(pAction3);pMenu->addAction(pAction4);//实现，模态对话框，非模态对话框，消息框，文件对话框connect(pMenu,&QMenu::triggered,[=](QAction* action){if(action->text()=="模态对话框"){qDebug()<<"模态对话框"<<endl;QDialog* pDialog=new QDialog;pDialog->setWindowTitle("模态对话框");pDialog->exec();//**堵塞就是模态对话框**}if(action->text()=="非模态对话框"){qDebug()<<"非模态对话框"<<endl;QDialog* pDialog=new QDialog;pDialog->setWindowTitle("非模态对话框");pDialog->show();//**不堵塞就是非模态对话框**}if(action->text()=="消息框"){qDebug()<<"消息框"<<endl;int r=QMessageBox::question(this,"提问","喜不喜欢我");if(r==QMessageBox::Yes){qDebug()<<"好的"<<endl;}else{qDebug()<<"跪CPU"<<endl;}}if(action->text()=="文件对话框"){qDebug()<<"文件对话框"<<endl;QString str=QFileDialog::getOpenFileName(this,"找文件","source(*.cpp *.c);;""head(*.h);;""tex(*.txt);;""all(*.*)");qDebug()<<str<<endl;}});
}