QT 各种小技巧

「爱情、让人受尽委屈。」 2022-12-23 00:56 127阅读 0赞

#### 获取命令行启动参数 ####

// 获取命令行参数
    QStringList arguments = QCoreApplication::arguments();

#### 断开某对信号槽的connect ####

QMetaObject::Connection conn;
    conn = connect(this,&TcpSocket::readyRead,this,&TcpSocket::readData);
    disconnect(conn);

#### 查找本窗口的子控件 ####

QList<QLabel*> labelList = findChildren<QLabel*>();

QLabel * label = findChild<QLabel *>("label_username");

#### 获取指定文件夹下所有文件 ####

// 获取所有文件名
    	QDir dir(FolderPath);
    	FolderPath= dir.fromNativeSeparators(FolderPath);// "\\"转为"/" 
    	if (!dir.exists()) mImgNames = QStringList("");
    	dir.setFilter(QDir::Files);
    	dir.setSorting(QDir::Name);
    	dir.setNameFilters(QString("*.tiff;*.tif").split(";"));
    	mImgNames = dir.entryList();
    	for (int i = 0; i < mImgNames.size(); ++i)
    	{ 
    		qDebug() << "entryList: " << i << "-" << FolderPath+ "/" +mImgNames[i];
    	}

#### 获取指定文件夹下所有文件夹 ####

// 获取所有文件夹名
    	QDir dir(FolderPath);
    	mFolderPath = dir.fromNativeSeparators(FolderPath);// "\\"转为"/" 
    	if (!dir.exists()) mImgNames = QStringList("");
    	dir.setFilter(QDir::Dirs | QDir::NoDotAndDotDot);
    	dir.setSorting(QDir::Name);
    	mImgNames = dir.entryList();
    	for (int i = 0; i < mImgNames.size(); ++i)
    	{ 
    		qDebug() << "entryList: " << i << "-" << FolderPath + "/" +mImgNames[i];
    	}

#### 去掉对话框上的问号 ####

setWindowFlags(Qt::CustomizeWindowHint | Qt::WindowCloseButtonHint);

#### 添加对话框上的最小化和最大化按钮 ####

//设置窗体最大化和最小化
        Qt::WindowFlags windowFlag  = Qt::Dialog;
        windowFlag                  |= Qt::WindowMinimizeButtonHint;
        windowFlag                  |= Qt::WindowMaximizeButtonHint;
        windowFlag                  |= Qt::WindowCloseButtonHint;
        setWindowFlags(windowFlag);

#### 只保留对话框的关闭按钮 ####

setWindowFlags(Qt::Window | Qt::WindowTitleHint | Qt::CustomizeWindowHint | Qt::WindowCloseButtonHint);

#### QT 写文件 ####

QString fileName = QDir::currentPath() + QDir::separator() + QString("startparam.tmp");
    fileName = QDir::fromNativeSeparators(fileName);
    //创建文件对象
    QFile file;
    //关联文件名字
    file.setFileName(fileName);
    //打开文件,只写方式
    bool isOK = file.open(QIODevice::WriteOnly);
    if (isOK == true) { 
    	//write files
    	//QString -> QByteArray
    	//file.write(str.toUtf8());
    	//QString -> C++ string ->char*
    	file.write(param.data());
    }
    file.close();

#### QT 读文件 ####

QString path = QFileDialog::getOpenFileName(this, "open", "./", "TXT(*.txt)");
        if(path.isEmpty() == false){ 
            //文件对象
            QFile file(path);
    
            //打开文件
            bool isOK = file.open(QIODevice::ReadOnly);
            if(isOK == true){ 
    #if 0
                //读文件,默认只识别UTF-8
               QByteArray array = file.readAll();//
               //显示到编辑区
               ui->textEdit->setText(array);
    #endif
                QByteArray array;
                while (file.atEnd() == false) { 
                    //读一行
                   array +=  file.readLine();
                   ui->textEdit->setText(array);
                }
    
            }
            file.close();
        }