QT小例子 ---文件查找

#ifndef WINDOW_H
#define WINDOW_H

#include <QDialog>
#include <QDir>

QT_BEGIN_NAMESPACE
class QComboBox;
class QLabel;
class QPushButton;
class QTableWidget;
class QTableWidgetItem;
QT_END_NAMESPACE

//! [0]
class Window : public QDialog
{
Q_OBJECT

public:
Window(QWidget *parent = 0);

private slots:
void browse();
void find();
void openFileOfItem(int row, int column);

private:
QStringList findFiles(const QStringList &files, const QString &text);
void showFiles(const QStringList &files);
QPushButton *createButton(const QString &text, const char *member);
QComboBox *createComboBox(const QString &text = QString());
void createFilesTable();

QComboBox *fileComboBox;
QComboBox *textComboBox;
QComboBox *directoryComboBox;
QLabel *fileLabel;
QLabel *textLabel;
QLabel *directoryLabel;
QLabel *filesFoundLabel;
QPushButton *browseButton;
QPushButton *findButton;
QTableWidget *filesTable;

QDir currentDir;
};
//! [0]

#endif

#include <QtGui>

#include "window.h"

//! [0]
Window::Window(QWidget *parent)
: QDialog(parent)
{
browseButton = createButton(tr("&Browse..."), SLOT(browse()));
findButton = createButton(tr("&Find"), SLOT(find()));

fileComboBox = createComboBox(tr("*"));
textComboBox = createComboBox();
directoryComboBox = createComboBox(QDir::currentPath());

fileLabel = new QLabel(tr("Named:"));
textLabel = new QLabel(tr("Containing text:"));
directoryLabel = new QLabel(tr("In directory:"));
filesFoundLabel = new QLabel;

createFilesTable();
//! [0]

//! [1]
QHBoxLayout *buttonsLayout = new QHBoxLayout;
buttonsLayout->addStretch();
buttonsLayout->addWidget(findButton);

QGridLayout *mainLayout = new QGridLayout;
mainLayout->addWidget(fileLabel, 0, 0);
mainLayout->addWidget(fileComboBox, 0, 1, 1, 2);
mainLayout->addWidget(textLabel, 1, 0);
mainLayout->addWidget(textComboBox, 1, 1, 1, 2);
mainLayout->addWidget(directoryLabel, 2, 0);
mainLayout->addWidget(directoryComboBox, 2, 1);
mainLayout->addWidget(browseButton, 2, 2);
mainLayout->addWidget(filesTable, 3, 0, 1, 3);
mainLayout->addWidget(filesFoundLabel, 4, 0, 1, 3);
mainLayout->addLayout(buttonsLayout, 5, 0, 1, 3);
setLayout(mainLayout);

setWindowTitle(tr("Find Files"));
resize(700, 300);
}
//! [1]

//! [2]
void Window::browse()
{
QString directory = QFileDialog::getExistingDirectory(this,
tr("Find Files"), QDir::currentPath());

if (!directory.isEmpty()) {
if (directoryComboBox->findText(directory) == -1)
directoryComboBox->addItem(directory);
directoryComboBox->setCurrentIndex(directoryComboBox->findText(directory));
}
}
//! [2]

static void updateComboBox(QComboBox *comboBox)
{
if (comboBox->findText(comboBox->currentText()) == -1)
comboBox->addItem(comboBox->currentText());
}

//! [3]
void Window::find()
{
filesTable->setRowCount(0);

QString fileName = fileComboBox->currentText();
QString text = textComboBox->currentText();
QString path = directoryComboBox->currentText();
//! [3]

updateComboBox(fileComboBox);
updateComboBox(textComboBox);
updateComboBox(directoryComboBox);

//! [4]
currentDir = QDir(path);
QStringList files;
if (fileName.isEmpty())
fileName = "*";
files = currentDir.entryList(QStringList(fileName),
QDir::Files | QDir::NoSymLinks);

if (!text.isEmpty())
files = findFiles(files, text);
showFiles(files);
}
//! [4]

//! [5]
QStringList Window::findFiles(const QStringList &files, const QString &text)
{
QProgressDialog progressDialog(this);
progressDialog.setCancelButtonText(tr("&Cancel"));
progressDialog.setRange(0, files.size());
progressDialog.setWindowTitle(tr("Find Files"));

//! [5] //! [6]
QStringList foundFiles;

for (int i = 0; i < files.size(); ++i) {
progressDialog.setValue(i);
progressDialog.setLabelText(tr("Searching file number %1 of %2...")
.arg(i).arg(files.size()));
qApp->processEvents();
//! [6]

if (progressDialog.wasCanceled())
break;

//! [7]
QFile file(currentDir.absoluteFilePath(files[i]));

if (file.open(QIODevice::ReadOnly)) {
QString line;
QTextStream in(&file);
while (!in.atEnd()) {
if (progressDialog.wasCanceled())
break;
line = in.readLine();
if (line.contains(text)) {
foundFiles << files[i];
break;
}
}
}
}
return foundFiles;
}
//! [7]

//! [8]
void Window::showFiles(const QStringList &files)
{
for (int i = 0; i < files.size(); ++i) {
QFile file(currentDir.absoluteFilePath(files[i]));
qint64 size = QFileInfo(file).size();

QTableWidgetItem *fileNameItem = new QTableWidgetItem(files[i]);
fileNameItem->setFlags(fileNameItem->flags() ^ Qt::ItemIsEditable);
QTableWidgetItem *sizeItem = new QTableWidgetItem(tr("%1 KB")
.arg(int((size + 1023) / 1024)));
sizeItem->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
sizeItem->setFlags(sizeItem->flags() ^ Qt::ItemIsEditable);

int row = filesTable->rowCount();
filesTable->insertRow(row);
filesTable->setItem(row, 0, fileNameItem);
filesTable->setItem(row, 1, sizeItem);
}
filesFoundLabel->setText(tr("%1 file(s) found").arg(files.size()) +
(" (Double click on a file to open it)"));
}
//! [8]

//! [9]
QPushButton *Window::createButton(const QString &text, const char *member)
{
QPushButton *button = new QPushButton(text);
connect(button, SIGNAL(clicked()), this, member);
return button;
}
//! [9]

//! [10]
QComboBox *Window::createComboBox(const QString &text)
{
QComboBox *comboBox = new QComboBox;
comboBox->setEditable(true);
comboBox->addItem(text);
comboBox->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
return comboBox;
}
//! [10]

//! [11]
void Window::createFilesTable()
{
filesTable = new QTableWidget(0, 2);
filesTable->setSelectionBehavior(QAbstractItemView::SelectRows);

QStringList labels;
labels << tr("File Name") << tr("Size");
filesTable->setHorizontalHeaderLabels(labels);
filesTable->horizontalHeader()->setResizeMode(0, QHeaderView::Stretch);
filesTable->verticalHeader()->hide();
filesTable->setShowGrid(false);

connect(filesTable, SIGNAL(cellActivated(int,int)),
this, SLOT(openFileOfItem(int,int)));
}
//! [11]

//! [12]

void Window::openFileOfItem(int row, int /* column */)
{
QTableWidgetItem *item = filesTable->item(row, 0);

QDesktopServices::openUrl(QUrl::fromLocalFile(currentDir.absoluteFilePath(item->text())));
}

//! [12]

#include <QApplication>

#include "window.h"

int main(int argc, char *argv[])
{
QApplication app(argc, argv);
Window window;
window.show();
return app.exec();
}