convertdialog.cpp

Qt4的一些例子

#include <QtGui>

#include "convertdialog.h"

ConvertDialog::ConvertDialog(QWidget *parent)
    : QDialog(parent)
{
    setupUi(this);

    connect(&process, SIGNAL(readyReadStandardError()),
            this, SLOT(updateOutputTextEdit()));
    connect(&process, SIGNAL(finished(int, QProcess::ExitStatus)),
            this, SLOT(processFinished(int, QProcess::ExitStatus)));
    connect(&process, SIGNAL(error(QProcess::ProcessError)),
            this, SLOT(processError(QProcess::ProcessError)));
}

void ConvertDialog::on_browseButton_clicked()
{
    QString initialName = sourceFileEdit->text();
    if (initialName.isEmpty())
        initialName = QDir::homePath();
    QString fileName =
            QFileDialog::getOpenFileName(this, tr("Choose File"),
                                         initialName);
    fileName = QDir::convertSeparators(fileName);
    if (!fileName.isEmpty()) {
        sourceFileEdit->setText(fileName);
        convertButton->setEnabled(true);
    }
}

void ConvertDialog::on_convertButton_clicked()
{
    QString sourceFile = sourceFileEdit->text();
    targetFile = QFileInfo(sourceFile).path() + QDir::separator()
                 + QFileInfo(sourceFile).baseName() + "."
                 + targetFormatComboBox->currentText().toLower();
    convertButton->setEnabled(false);
    outputTextEdit->clear();

    QStringList args;
    if (enhanceCheckBox->isChecked())
        args << "-enhance";
    if (monochromeCheckBox->isChecked())
        args << "-monochrome";
    args << sourceFile << targetFile;

    process.start("convert", args);
}

void ConvertDialog::updateOutputTextEdit()
{
    QByteArray newData = process.readAllStandardError();
    QString text = outputTextEdit->toPlainText()
                   + QString::fromLocal8Bit(newData);
    outputTextEdit->setPlainText(text);
}

void ConvertDialog::processFinished(int exitCode,
                                    QProcess::ExitStatus exitStatus)
{
    if (exitStatus == QProcess::CrashExit) {
        outputTextEdit->append(tr("Conversion program crashed"));
    } else if (exitCode != 0) {
        outputTextEdit->append(tr("Conversion failed"));
    } else {
        outputTextEdit->append(tr("File %1 created").arg(targetFile));
    }
    convertButton->setEnabled(true);
}

void ConvertDialog::processError(QProcess::ProcessError error)
{
    if (error == QProcess::FailedToStart) {
        outputTextEdit->append(tr("Conversion program not found"));
        convertButton->setEnabled(true);
    }
}