Simple Text Viewer Example

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#include "assistant.h"
#include "findfiledialog.h"
#include "textedit.h"

#include <QComboBox>
#include <QDialogButtonBox>
#include <QDir>
#include <QFileDialog>
#include <QHBoxLayout>
#include <QLabel>
#include <QPushButton>
#include <QToolButton>
#include <QTreeWidget>
#include <QTreeWidgetItem>

FindFileDialog::FindFileDialog(TextEdit *editor, Assistant *assistant)
    : QDialog(editor)
{
    currentAssistant = assistant;
    currentEditor = editor;

    createButtons();
    createComboBoxes();
    createFilesTree();
    createLabels();
    createLayout();

    directoryComboBox->addItem(QDir::toNativeSeparators(QDir::currentPath()));
    fileNameComboBox->addItem("*");
    findFiles();

    setWindowTitle(tr("Find File"));
}

void FindFileDialog::browse()
{
    QString currentDirectory = directoryComboBox->currentText();
    QString newDirectory = QFileDialog::getExistingDirectory(this,
                               tr("Select Directory"), currentDirectory);
    if (!newDirectory.isEmpty()) {
        directoryComboBox->addItem(QDir::toNativeSeparators(newDirectory));
        directoryComboBox->setCurrentIndex(directoryComboBox->count() - 1);
        update();
    }
}

void FindFileDialog::help()
{
    currentAssistant->showDocumentation("filedialog.html");
}

void FindFileDialog::openFile(QTreeWidgetItem *item)
{
    if (!item) {
        item = foundFilesTree->currentItem();
        if (!item)
            return;
    }

    QString fileName = item->text(0);
    QString path = directoryComboBox->currentText() + QDir::separator();

    currentEditor->setContents(path + fileName);
    close();
}

void FindFileDialog::update()
{
    findFiles();
    buttonBox->button(QDialogButtonBox::Open)->setEnabled(
            foundFilesTree->topLevelItemCount() > 0);
}

void FindFileDialog::findFiles()
{
    QRegExp filePattern(fileNameComboBox->currentText() + "*");
    filePattern.setPatternSyntax(QRegExp::Wildcard);

    QDir directory(directoryComboBox->currentText());

    const QStringList allFiles = directory.entryList(QDir::Files | QDir::NoSymLinks);
    QStringList matchingFiles;

    for (const QString &file : allFiles) {
        if (filePattern.exactMatch(file))
            matchingFiles << file;
    }
    showFiles(matchingFiles);
}

void FindFileDialog::showFiles(const QStringList &files)
{
    foundFilesTree->clear();

    for (int i = 0; i < files.count(); ++i) {
        QTreeWidgetItem *item = new QTreeWidgetItem(foundFilesTree);
        item->setText(0, files[i]);
    }

    if (files.count() > 0)
        foundFilesTree->setCurrentItem(foundFilesTree->topLevelItem(0));
}

void FindFileDialog::createButtons()
{
    browseButton = new QToolButton;
    browseButton->setText(tr("..."));
    connect(browseButton, SIGNAL(clicked()), this, SLOT(browse()));

    buttonBox = new QDialogButtonBox(QDialogButtonBox::Open
                                     | QDialogButtonBox::Cancel
                                     | QDialogButtonBox::Help);
    connect(buttonBox, SIGNAL(accepted()), this, SLOT(openFile()));
    connect(buttonBox, SIGNAL(rejected()), this, SLOT(reject()));
    connect(buttonBox, SIGNAL(helpRequested()), this, SLOT(help()));
}

void FindFileDialog::createComboBoxes()
{
    directoryComboBox = new QComboBox;
    fileNameComboBox = new QComboBox;

    fileNameComboBox->setEditable(true);
    fileNameComboBox->setSizePolicy(QSizePolicy::Expanding,
                                    QSizePolicy::Preferred);

    directoryComboBox->setMinimumContentsLength(30);
    directoryComboBox->setSizeAdjustPolicy(
            QComboBox::AdjustToMinimumContentsLength);
    directoryComboBox->setSizePolicy(QSizePolicy::Expanding,
                                     QSizePolicy::Preferred);

    connect(fileNameComboBox, SIGNAL(editTextChanged(QString)),
            this, SLOT(update()));
    connect(directoryComboBox, SIGNAL(currentIndexChanged(QString)),
            this, SLOT(update()));
}

void FindFileDialog::createFilesTree()
{
    foundFilesTree = new QTreeWidget;
    foundFilesTree->setColumnCount(1);
    foundFilesTree->setHeaderLabels(QStringList(tr("Matching Files")));
    foundFilesTree->setRootIsDecorated(false);
    foundFilesTree->setSelectionMode(QAbstractItemView::SingleSelection);

    connect(foundFilesTree, SIGNAL(itemActivated(QTreeWidgetItem*,int)),
            this, SLOT(openFile(QTreeWidgetItem*)));
}

void FindFileDialog::createLabels()
{
    directoryLabel = new QLabel(tr("Search in:"));
    fileNameLabel = new QLabel(tr("File name (including wildcards):"));
}

void FindFileDialog::createLayout()
{
    QHBoxLayout *fileLayout = new QHBoxLayout;
    fileLayout->addWidget(fileNameLabel);
    fileLayout->addWidget(fileNameComboBox);

    QHBoxLayout *directoryLayout = new QHBoxLayout;
    directoryLayout->addWidget(directoryLabel);
    directoryLayout->addWidget(directoryComboBox);
    directoryLayout->addWidget(browseButton);

    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addLayout(fileLayout);
    mainLayout->addLayout(directoryLayout);
    mainLayout->addWidget(foundFilesTree);
    mainLayout->addStretch();
    mainLayout->addWidget(buttonBox);
    setLayout(mainLayout);
}