嵌入式项目之QT页面制作

学习一下QT的基本语法以及基本操作

基本语法

设置title名字

this->setWindowTitle("xxxx");

设置具体字体型号

Qfont f("仿宋" , 14); //创建字体对象
ui->lineEdit->setFont(f);

按钮上设置图片

QIcon con("D:\\xxx\\xxx\\xxx\\xxx.png");
ui->xxxButton->setIcon(con);

改变按钮颜色

ui->equalButton->setStyleSheet("background:blue");

定时器事件

1、使用QObject成员函数
this->startTimer(Timeout); //返回成功创建的定时器id
设置timerEvent事件函数
timerEvent(QTimerEvent *event)
killTimer(id)2、使用Qtimer这个类  
#include <QTimer>
QTimer->start(Timeout);
connect(timer , &QTimer::timeout , this ,&Widget::timeoutSlot);
timer->stop()

用Qt做一个简单的notepad

#include "mainwindow.h"
#include "ui_mainwindow.h"MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);connect(ui->newaction , &QAction::triggered , this , &MainWindow::newactionslot);connect(ui->openaction , &QAction::triggered , this , &MainWindow::openactionslot);connect(ui->saveoption , &QAction::triggered , this , &MainWindow::saveactionslot);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::newactionslot()
{ui->textEdit->clear();this->setWindowTitle("新建文件夹.txt");
}void MainWindow::openactionslot()
{QString fileName = QFileDialog::getOpenFileName(this, "选择一个文件",QCoreApplication::applicationFilePath(),"*.cpp , *.c , *.txt");if(fileName.isEmpty()){QMessageBox::warning(this , "警告" , "请选择一个文件");}else{//qDebug() << fileName;QFile file(fileName);         //创建文件对象file.open(QIODevice::ReadOnly);QByteArray ba = file.readAll();ui->textEdit->setText(QString(ba));file.close();}
}void MainWindow::saveactionslot()
{QString fileName = QFileDialog::getSaveFileName(this, "选择一个文件",QCoreApplication::applicationFilePath());if(fileName.isEmpty()){QMessageBox::warning(this , "警告" , "请选择一个文件");}else{QFile file(fileName);file.open(QIODevice::WriteOnly);//ui->textEdit->toPlainText(); //显示QByteArray ba;ba.append(ui->textEdit->toPlainText().toUtf8());file.write(ba);file.close();QMessageBox::information(this, "保存成功", "文件已成功保存！");}
}

上述代码不能实现CTRL+S自动保存功能，接下 来要实现其功能，在QT中都被封装成事件，我们要重写虚函数，实现热键功能

void MainWindow::keyPressEvent(QKeyEvent * k)
{if(k->modifiers() == Qt::ControlModifier && k->key() == QT::key_S){saveactionslot();}
}

QT网络部分

为了兼容Windows和Linux，QT将网络接口封装成类。这样既可以在Linux和Windows运行。

在QT里面使用网络要在.pro文件的第一行加上network。

Client端

#include <QTcpSocket>

#include "widget.h"
#include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);socket = new QTcpSocket;
}Widget::~Widget()
{delete ui;
}void Widget::on_cancelButton_clicked()
{this->close();
}void Widget::on_connectButton_clicked()
{QString ip = ui->iplineEdit->text();QString port = ui->portlineEdit->text();// qDebug() << ip;// qDebug() << port;socket->connectToHost(QHostAddress(ip), port.toShort());qDebug() << ip;qDebug() << port;connect(socket , &QTcpSocket::connected , [this](){QMessageBox::information(this , "连接提示" , "连接服务器成功");});connect(socket , &QTcpSocket::disconnected , [this](){QMessageBox::warning(this , "连接提示" , "连接异常 网络断开");});
}

Server端

服务器端需要包含两个头文件

#include <QTcpServer>
#include <QTcpSocket>

#include "widget.h"
#include "ui_widget.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);server = new QTcpServer;server->listen(QHostAddress::AnyIPv4 , PORT);connect(server , &QTcpServer::newConnection , this , &Widget::newclienthandler);
}Widget::~Widget()
{delete ui;
}void Widget::newclienthandler()
{//建立TCP连接QTcpSocket*socket = server->nextPendingConnection();//socket->peerAddress();//socket->peerPort();ui->IPlineEdit->setText(socket->peerAddress().toString());ui->IPlineEdit->setText(QString::number(socket->peerPort()));
}