qt 5.x 学习笔记 (2)

Posted by 111qqz on Tuesday, May 16, 2017

TOC

先来放一波过程中用到的资料和官方文档好了。

basic layout_qt5.8

QBoxLayout Class_qt5.8

QString Class 5.8

QChar Class qt 5.8

Standard Dialogs Example qt 5.8

更新的部分还是放在最前面好了。。。

convert from QString to char *的时候有个坑。。。

举个栗子。。。。

int main(int argc, char **argv)
{
 QApplication app(argc, argv);
 QString str1 = "Test";
 QByteArray ba = str1.toLatin1();
 const char *c_str2 = ba.data(); 
 printf("str2: %s", c_str2);
 return app.exec();   
}

目前基本框架出来了。。。

可以打开一个文件。。加密。。保存。。。

加密算法部分暂时用倒序输出代替。。。

界面布局还没搞。。。一些提示之类的还没搞。。。。。。。。

接下来要做的。。。大概就是把des写进去了。。。

放一波代码好了。。。

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef DIALOG_H
#define DIALOG_H

#include <QWidget>
#include <QTextEdit>

class QCheckBox;
class QLabel;
class QErrorMessage;

class DialogOptionsWidget;

class Dialog : public QWidget
{
    Q_OBJECT

public:
    Dialog(QWidget *parent = 0);

private slots:

    void setText();


    void setOpenFileName();
    void beginToCal();
    void setSaveFileName();
    void criticalMessage();
    void informationMessage();
    void questionMessage();
    void warningMessage();
    void errorMessage();

private:

    QLabel *textLabel;


    QLabel *openFileNameLabel;

    QLabel *saveFileNameLabel;
    QLabel *criticalLabel;
    QLabel *informationLabel;
    QLabel *questionLabel;
    QLabel *warningLabel;
    QLabel *errorLabel;
    QErrorMessage *errorMessageDialog;
    DialogOptionsWidget *fileDialogOptionsWidget;
    DialogOptionsWidget *colorDialogOptionsWidget;
    DialogOptionsWidget *fontDialogOptionsWidget;
    QString openFilesPath;
    QTextEdit *textEdit;
    QString QTextSt;
};

#endif






/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QtWidgets>
#include <QTextEdit>

#include "dialog.h"

#define MESSAGE \
    Dialog::tr("<p>Message boxes have a caption, a text, " \
               "and any number of buttons, each with standard or custom texts." \
               "<p>Click a button to close the message box. Pressing the Esc button " \
               "will activate the detected escape button (if any).")
#define MESSAGE_DETAILS \
    Dialog::tr("If a message box has detailed text, the user can reveal it " \
               "by pressing the Show Details... button.")

class DialogOptionsWidget : public QGroupBox
{
public:
    explicit DialogOptionsWidget(QWidget *parent = 0);

    void addCheckBox(const QString &text, int value);
    void addSpacer();
    int value() const;

private:
    typedef QPair<QCheckBox *, int> CheckBoxEntry;
    QVBoxLayout *layout;
    QList<CheckBoxEntry> checkBoxEntries;
};

DialogOptionsWidget::DialogOptionsWidget(QWidget *parent) :
    QGroupBox(parent) , layout(new QVBoxLayout)
{
    //setTitle(Dialog::tr("Optionsssss"));
   // textEdit = new QTextEdit(this);
    //setCentralWidget(textEdit);
    //textEdit = new QTextEdit(this);
    //setCentralWidget(textEdit);

  //  setLayout(layout);
}

void DialogOptionsWidget::addCheckBox(const QString &text, int value)
{
    QCheckBox *checkBox = new QCheckBox(text);
    layout->addWidget(checkBox);
    checkBoxEntries.append(CheckBoxEntry(checkBox, value));
}

void DialogOptionsWidget::addSpacer()
{
    layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding));
}

int DialogOptionsWidget::value() const
{
    int result = 0;
    foreach (const CheckBoxEntry &checkboxEntry, checkBoxEntries)
        if (checkboxEntry.first->isChecked())
            result |= checkboxEntry.second;
    return result;
}

Dialog::Dialog(QWidget *parent)
    : QWidget(parent)
{
    QVBoxLayout *verticalLayout;
    if (QGuiApplication::styleHints()->showIsFullScreen() || QGuiApplication::styleHints()->showIsMaximized()) {
        QHBoxLayout *horizontalLayout = new QHBoxLayout(this);
        QGroupBox *groupBox = new QGroupBox(QGuiApplication::applicationDisplayName(), this);
        horizontalLayout->addWidget(groupBox);
        verticalLayout = new QVBoxLayout(groupBox);
    } else {
        verticalLayout = new QVBoxLayout(this);
    }

    QToolBox *toolbox = new QToolBox;
    verticalLayout->addWidget(toolbox);

    errorMessageDialog = new QErrorMessage(this);

    int frameStyle = QFrame::Sunken | QFrame::Panel;

    textLabel = new QLabel;
    textLabel->setFrameStyle(frameStyle);
    QPushButton *textButton = new QPushButton(tr("加密文件"));

    openFileNameLabel = new QLabel;
    openFileNameLabel->setFrameStyle(frameStyle);
    QPushButton *openFileNameButton =
            new QPushButton(tr("打开文件"));

    QPushButton *calButton =
            new QPushButton(tr("加密"));



    saveFileNameLabel = new QLabel;
    saveFileNameLabel->setFrameStyle(frameStyle);
    QPushButton *saveFileNameButton =
            new QPushButton(tr("QFileDialog::get&SaveFileName()"));

    criticalLabel = new QLabel;
    criticalLabel->setFrameStyle(frameStyle);
    QPushButton *criticalButton =
            new QPushButton(tr("QMessageBox::critica&l()"));

    informationLabel = new QLabel;
    informationLabel->setFrameStyle(frameStyle);
    QPushButton *informationButton =
            new QPushButton(tr("QMessageBox::i&nformation()"));

    questionLabel = new QLabel;
    questionLabel->setFrameStyle(frameStyle);
    QPushButton *questionButton =
            new QPushButton(tr("QMessageBox::&question()"));

    warningLabel = new QLabel;
    warningLabel->setFrameStyle(frameStyle);
    QPushButton *warningButton = new QPushButton(tr("QMessageBox::&warning()"));

    errorLabel = new QLabel;
    errorLabel->setFrameStyle(frameStyle);
    QPushButton *errorButton =
            new QPushButton(tr("QErrorMessage::showM&essage()"));


    connect(textButton, &QAbstractButton::clicked, this, &Dialog::setText);

    connect(openFileNameButton, &QAbstractButton::clicked,
            this, &Dialog::setOpenFileName);

    connect(calButton,&QAbstractButton::clicked,
            this,&Dialog::beginToCal);

    connect(saveFileNameButton, &QAbstractButton::clicked,
            this, &Dialog::setSaveFileName);
    connect(criticalButton, &QAbstractButton::clicked, this, &Dialog::criticalMessage);
    connect(informationButton, &QAbstractButton::clicked,
            this, &Dialog::informationMessage);
    connect(questionButton, &QAbstractButton::clicked, this, &Dialog::questionMessage);
    connect(warningButton, &QAbstractButton::clicked, this, &Dialog::warningMessage);
    connect(errorButton, &QAbstractButton::clicked, this, &Dialog::errorMessage);

    QWidget *page = new QWidget;
    QGridLayout *layout = new QGridLayout(page);
    layout->setColumnStretch(1, 1);
    layout->setColumnMinimumWidth(1, 250);

    layout->addWidget(textButton, 3, 0);
    layout->addWidget(textLabel, 3, 1);

    layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 5, 0);
    toolbox->addItem(page, tr("Input Dialogs"));

    const QString doNotUseNativeDialog = tr("Do not use native dialog");

    page = new QWidget;
    layout = new QGridLayout(page);
    layout->setColumnStretch(1, 1);

   /* colorDialogOptionsWidget = new DialogOptionsWidget;
    colorDialogOptionsWidget->addCheckBox(doNotUseNativeDialog, QColorDialog::DontUseNativeDialog);
    colorDialogOptionsWidget->addCheckBox(tr("Show alpha channel") , QColorDialog::ShowAlphaChannel);
    colorDialogOptionsWidget->addCheckBox(tr("No buttons") , QColorDialog::NoButtons);
    layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 1, 0);
    layout->addWidget(colorDialogOptionsWidget, 2, 0, 1 ,2);

    toolbox->addItem(page, tr("Color Dialog"));
    */

   // page = new QWidget;
   // layout = new QGridLayout(page);
   // layout->setColumnStretch(1, 1);
   // layout->addWidget(fontButton, 0, 0);
    //layout->addWidget(fontLabel, 0, 1);


    page = new QWidget;
    layout = new QGridLayout(page);
    layout->setColumnStretch(3,1);

    layout->addWidget(openFileNameButton, 1, 0);
    layout->addWidget(openFileNameLabel, 1,1);
    layout->addWidget(calButton,1,2);

    layout->addWidget(saveFileNameButton, 3, 0);
    layout->addWidget(saveFileNameLabel, 3, 1);
    fileDialogOptionsWidget = new DialogOptionsWidget;


    layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 4, 0);
    toolbox->addItem(page, tr("File Dialogs"));


    page = new QWidget;
    layout = new QGridLayout(page);
    layout->setColumnStretch(1, 1);
    layout->addWidget(criticalButton, 0, 0);
    layout->addWidget(criticalLabel, 0, 1);
    layout->addWidget(informationButton, 1, 0);
    layout->addWidget(informationLabel, 1, 1);
    layout->addWidget(questionButton, 2, 0);
    layout->addWidget(questionLabel, 2, 1);
    layout->addWidget(warningButton, 3, 0);
    layout->addWidget(warningLabel, 3, 1);
    layout->addWidget(errorButton, 4, 0);
    layout->addWidget(errorLabel, 4, 1);
    layout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding), 5, 0);

    toolbox->addItem(page, tr("Message Boxes"));

    setWindowTitle(QGuiApplication::applicationDisplayName());
}





void Dialog::setText()
{
    bool ok;
    QString text = QInputDialog::getText(this, tr("QInputDialog::getText()"),
                                         tr("User name:"), QLineEdit::Normal,
                                         QDir::home().dirName(), &ok);
    if (ok && !text.isEmpty())
        textLabel->setText(text);
}








void Dialog::setOpenFileName()
{
    const QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
    QString selectedFilter;
    QString fileName = QFileDialog::getOpenFileName(this,
                                tr("QFileDialog::getOpenFileName()"),
                                openFileNameLabel->text(),
                                tr("All Files (*);;Text Files (*.txt)"),
                                &selectedFilter,
                                options);
    if (!fileName.isEmpty())
    {

        openFileNameLabel->setText(fileName);
        qDebug()<<"filename:"<<fileName;
        QFile file(fileName);

        //不仅仅是if判断。。重点是执行了open操作。。。顺便返回值罢了。。kk最菜.jpg

        if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            QMessageBox::warning(this, tr("Read File"),
                                 tr("Cannot open file:\n%1").arg(fileName));
            return;
        }

        QTextStream in(&file);
        QTextSt = in.readAll();
        qDebug()<<"fileText:"<<QTextSt<<endl;
        qDebug()<<"TextLen:"<<QTextSt.length();
          file.close();
     }
}



void Dialog::beginToCal()
{
    int len = QTextSt.length();
    QString ret = "";
    for ( int i = len-1 ; i >=0 ; i--)
    {
           QChar tmp = QTextSt[i];
           ret+=tmp;

    }
    QTextSt = ret;
}

void Dialog::setSaveFileName()
{
    const QFileDialog::Options options = QFlag(fileDialogOptionsWidget->value());
    QString selectedFilter;
    QString fileName = QFileDialog::getSaveFileName(this,
                                tr("QFileDialog::getSaveFileName()"),
                                saveFileNameLabel->text(),
                                tr("All Files (*);;Text Files (*.txt)"),
                                &selectedFilter,
                                options);

    if (!fileName.isEmpty())
    {
        saveFileNameLabel->setText(fileName);
        QFile file(fileName);
        if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
            QMessageBox::warning(this, tr("Write File"),
                                       tr("Cannot open file:\n%1").arg(fileName));
            return;
        }
        QTextStream out(&file);
        qDebug()<<"save file text:"<<QTextSt<<endl;
        //out << textEdit->toPlainText();
        out<<QTextSt<<endl;
        file.close();
     }


}

void Dialog::criticalMessage()
{
    QMessageBox::StandardButton reply;
    reply = QMessageBox::critical(this, tr("QMessageBox::critical()"),
                                    MESSAGE,
                                    QMessageBox::Abort | QMessageBox::Retry | QMessageBox::Ignore);
    if (reply == QMessageBox::Abort)
        criticalLabel->setText(tr("Abort"));
    else if (reply == QMessageBox::Retry)
        criticalLabel->setText(tr("Retry"));
    else
        criticalLabel->setText(tr("Ignore"));
}

void Dialog::informationMessage()
{
    QMessageBox::StandardButton reply;
    reply = QMessageBox::information(this, tr("QMessageBox::information()"), MESSAGE);
    if (reply == QMessageBox::Ok)
        informationLabel->setText(tr("OK"));
    else
        informationLabel->setText(tr("Escape"));
}

void Dialog::questionMessage()
{
    QMessageBox::StandardButton reply;
    reply = QMessageBox::question(this, tr("QMessageBox::question()"),
                                    MESSAGE,
                                    QMessageBox::Yes | QMessageBox::No | QMessageBox::Cancel);
    if (reply == QMessageBox::Yes)
        questionLabel->setText(tr("Yes"));
    else if (reply == QMessageBox::No)
        questionLabel->setText(tr("No"));
    else
        questionLabel->setText(tr("Cancel"));
}

void Dialog::warningMessage()
{
    QMessageBox msgBox(QMessageBox::Warning, tr("QMessageBox::warning()"),
                       MESSAGE, 0, this);
    msgBox.setDetailedText(MESSAGE_DETAILS);
    msgBox.addButton(tr("Save &Again"), QMessageBox::AcceptRole);
    msgBox.addButton(tr("&Continue"), QMessageBox::RejectRole);
    if (msgBox.exec() == QMessageBox::AcceptRole)
        warningLabel->setText(tr("Save Again"));
    else
        warningLabel->setText(tr("Continue"));

}

void Dialog::errorMessage()
{
    errorMessageDialog->showMessage(
            tr("This dialog shows and remembers error messages. "
               "If the checkbox is checked (as it is by default), "
               "the shown message will be shown again, "
               "but if the user unchecks the box the message "
               "will not appear again if QErrorMessage::showMessage() "
               "is called with the same message."));
    errorLabel->setText(tr("If the box is unchecked, the message "
                           "won't appear again."));
}






/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QApplication>
#include <QStyleHints>
#include <QDesktopWidget>
#include <QTranslator>
#include <QLocale>
#include <QLibraryInfo>

#include "dialog.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QGuiApplication::setApplicationDisplayName(Dialog::tr("Standard Dialogs"));

#ifndef QT_NO_TRANSLATION
    QString translatorFileName = QLatin1String("qt_");
    translatorFileName += QLocale::system().name();
    QTranslator *translator = new QTranslator(&app);
    if (translator->load(translatorFileName, QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
        app.installTranslator(translator);
#endif

    Dialog dialog;
    if (!QGuiApplication::styleHints()->showIsFullScreen() && !QGuiApplication::styleHints()->showIsMaximized()) {
        const QRect availableGeometry = QApplication::desktop()->availableGeometry(&dialog);
        dialog.resize(availableGeometry.width() * 4 / 5, availableGeometry.height() * 2 / 3);
        dialog.move((availableGeometry.width() - dialog.width()) / 2,
                    (availableGeometry.height() - dialog.height()) / 2);
    }
    dialog.show();

    return app.exec();
}

记录一些坑?(其实也不算坑。。。

目前我的做法是有一个全局的QString。。。

我是打算直接拆分包装这个QString。。。每8位。。。

然后QString的[] operator得到的是QCharRef类型。。。。

QString之前有的toAscii()被移除了。。。。

qt 5.2以后的方法叫:toLatin1()

qt5.8_doc_toLatin1()

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