I am trying to populate a QListWidget (in icon view) with a QFileSystemModel. I want to list folders and only files with specific extension. I want to show the preview of my files as their thumbnail, so I am subclassing QIconProvider class and I am setting this to my model.
Before setting my QIconProvider to the model I have already filtered the files that I want on my model, icon(const QFileInfo & info) is called for every file that exists in the listed directory.
I have found a work around checking the extension of the file before returning my custom icon, but I am wondering if thre is a way to avoid this.
m_itemsModel = new QFileSystemModel(this);
m_itemsModel->setFilter(QDir::AllEntries | QDir::NoDotAndDotDot);
m_itemsModel->setRootPath(QDir::homePath());
QStringList filters = formatsList();
m_itemsModel->setNameFilters(filters);
m_itemsModel->setNameFilterDisables(false);
ui.listView->setModel(m_itemsModel);
m_itemsModel->setIconProvider(new ThumbnailIconProvider(QRect(0, 0, 50, 50)));
my QIconProvider:
ThumbnailIconProvider::ThumbnailIconProvider(const QRect &rect)
: QFileIconProvider() {
m_rect = rect;
}
QIcon ThumbnailIconProvider::icon(const QFileInfo & info) const {
static QStringList filters = formatsList();
QString fileName = info.fileName();
QString extension = "*" + fileName.right(fileName.length() - fileName.lastIndexOf("."));
if (info.isFile() && filters.contains(extension)) {
QString path = info.absoluteFilePath();
FileDetails details = fileDetailsFromPathForRect(path, m_rect);
QPixmap pixmap = QPixmap::fromImage(details.image);
QIcon icon(pixmap);
return icon;
}
else
return QFileIconProvider::icon(info);
}
Any ideas please?
I am trying to implement copy/cut/paste in a complex application.
I have a QGraphicsScene that can contain QGraphicsItem subtypes of varied subtypes, fairly complex (with Item as a second parent storing custom properties).
I would copy/cut selected items, and paste them back in place.
I already have implemented it using a local version: a list of items.
void copyItemsActionOld()
{
foreach(QGraphicsItem* qItem, selectedItems())
{
Item* newItem = (dynamic_cast<Item*>(qItem))->createItemCopy();
m_itemClipboard.append(newItem);
}
}
On paste, I make a copy of all items in clipboard and add them to the scene. So simple.....
BUT
I need to implement it using the global system clipboard.
I saw that creating a custom mime type is as simple as calling setData on a QMimeData object, after I make up a format name... (I hope that is true)
static const QString _mimeType("application/myItem");
void copyItemsAction()
{
QMimeData* _mimeData = new QMimeData;
2 QByteArray _itemData = ?????;
_mimeData->setData(_mimeType, _itemData);
QClipboard* _clipboard = QApplication::clipboard();
_clipboard->clear();
_clipboard->setMimeData(_mimeData);
}
void pasteItemsAction()
{
QClipboard* _clipboard = QApplication::clipboard();
const QMimeData* _mimeData = _clipboard->mimeData();
QStringList _formats = _mimeData->formats();
foreach (QString _format, _formats)
{
if (_format == _mimeType)
{
QByteArray _itemData = _mimeData->data(_mimeType);
3 // then do what ? How do I parse it ?
}
}
}
My questions
1) Are the above fragments for copyItemsAction and pasteItemsAction anywhere close to how clipboard actions should work ?
2) How can I put item data in the QByteArray ?
3) How do I parse the data in QByteArray ?
4) Do I need to register the custom mime-type anywhere else ? (other than what I just did in my two functions); and will it be multi-platform ?
I have already implemented save and load functionality for all items. Something like...
void Item::saveItem(QDataStream &outFile)
{
outFile << type;
outFile << width;
outFile << color.name();
}
Can I use this to place the items data in the QByteArray ? (How ?)
I was on the right track, and I kept adding code to my question until I found how to make it work:
static const QString _mimeType("application/myItem");
void copyItemsAction()
{
QByteArray _itemData;
QDataStream outData(&_itemData, QIODevice::WriteOnly);
outData << selectedItems().size();
foreach(QGraphicsItem* qItem, selectedItems())
{
Item* item = dynamic_cast<Item*>(qItem);
item->saveItem(outData);
}
QMimeData* _mimeData = new QMimeData;
_mimeData->setData(_mimeType, _itemData);
_mimeData->setText("My Items");
QClipboard* _clipboard = QApplication::clipboard();
_clipboard->clear();
_clipboard->setMimeData(_mimeData);
}
void pasteItemsAction()
{
QClipboard* _clipboard = QApplication::clipboard();
const QMimeData* _mimeData = _clipboard->mimeData();
QStringList _formats = _mimeData->formats();
foreach (QString _format, _formats)
{
if (_format == _mimeType)
{
QByteArray _itemData = _mimeData->data(_mimeType);
QDataStream inData(&_itemData, QIODevice::ReadOnly);
int itemsSize;
inData >> itemsSize;
for (int i = 0; i < itemsSize; ++i)
{
Item* item = ...
item->loadItem(inData);
}
}
}
}
So, for question 1, yes I was on the right track;
For questions 2 and 3 - I was able to use a QDataStream to serialize info to/from the QByteArray.
If there is a better / more effective / faster way, I would love to know...
For question 4 - it seems that I can use just about any string, if all I want is to copy/paste within a single instance of my application.
It is also true if I want to use it between multiple applications, multiple instances of my application, or for drag-and-drop - on most platforms. (It does not seem to work between multiple applications/instances in the embedded platform I target.)
Caveat - it fails frequently when another clipboard using application is open, in windows.
I'm trying to automatically add a backslash to valid file paths in a QLineEdit, which is used to show the current path of a QFileSystemModel.
The code looks as follows:
fileSystem = new QFileSystemModel;
fileSystem->setRootPath(QObject::tr("C:\\"));
QCompleter* fileSystemCompleter = new QCompleter(fileSystem);
fileSystemCompleter->setCaseSensitivity(Qt::CaseInsensitive);
fileTree = new QDeselectableTreeView();
fileTree->setModel(fileSystem);
fileTree->setRootIndex(fileSystem->index(fileSystem->rootPath()));
connect(fileTree, &QTreeView::clicked, [&] (QModelIndex index)
{
QString toAppend("");
if (fileSystem->isDir(index))
{
toAppend = '/';
}
fileSystemPathEdit->setText(fileSystem->filePath(index)+toAppend);
});
// path line edit
fileSystemPathEdit = new QLineEdit(fileSystem->rootPath());
fileSystemPathEdit->setPlaceholderText("Path...");
fileSystemPathEdit->setCompleter(fileSystemCompleter);
connect(fileSystemPathEdit, &QLineEdit::editingFinished, [&]()
{
// jump to that location
qDebug() << fileSystemPathEdit->text();
QModelIndex index = fileSystem->index(fileSystemPathEdit->text());
qDebug() << index;
fileTree->setExpanded(index,true);
fileTree->setCurrentIndex(index);
// CLOSE IF EMPTY
if (fileSystemPathEdit->text().isEmpty())
{
fileTree->collapseAll();
fileSystemPathEdit->setText(fileSystem->rootPath());
}
// append slashes to dirs
else if (fileSystem->isDir(index) && index.isValid())
{
qDebug() << "it's a dir";
if (!fileSystemPathEdit->text().endsWith('/',Qt::CaseInsensitive))
{
qDebug() << "added slash";
fileSystemPathEdit->setText(fileSystemPathEdit->text().append('/'));
qDebug() << fileSystemPathEdit->text();
}
}
this->update();
});
I get the following output when running the code:
"C:/export/home"
QModelIndex(0,0,0x3adb840,QFileSystemModel(0x1d9b7c0) )
it's a dir
added slash
"C:/export/home/"
It works ok when I push the Enter key from within the lineEdit, but if the text is set by the QCompleter, I still get the same debug output showing that the text has been changed, but the slash doesn't appear in the lineEdit. Does the QCompleter somehow unset the text?
This is a hack, but adding this connection to the QCompleter gives the desired behavior. I think there is a race condition when using editingFinished() at the same time that the QCompleter is activated, so adding delay allows the slash to be appended without being overridden. On the down side, that function know gets called several times to many per change. I'd still be interested in a better solution.
connect(fileSystemCompleter, activatedOverloadPtr, [&](QModelIndex index)
{
QTimer* timer = new QTimer;
timer->setSingleShot(true);
timer->setInterval(10);
connect(timer, &QTimer::timeout, fileSystemPathEdit, &QLineEdit::editingFinished);
timer->start();
});
I have addFile function in my TableModel class which inserts a new record at the end.
void TableModel::addFile(const QString &path)
{
beginInsertRows(QModelIndex(), list.size(),list.size());
TableItem item;
item.filename = path;
QFile file(path);
item.size = file.size();
item.status = StatusNew;
list << item;
endInsertRows();
}
This function works fine but instead of appending record at the end I would like to insert it at the top. Any pointers on how to update my existing function ?
I have already tried some combinations but there is no Luck.
There are two things that you need to do. First is to adjust the call to beginInsertRows. Because it is here that we are telling the model that we are adding rows, where they will go, and how many we are adding. Here is the method description:
void QAbstractItemModel::beginInsertRows ( const QModelIndex & parent,
int first, int last )
So in your case since you want to add a row at the first index, and only one row, we pass 0 as the index of the first item, and 0 which is the index of the last item we are adding (because of course we are only adding one item).
beginInsertRows(modelIndex(), 0, 0);
Next we have to provide the data for the item. I assume that 'list' is a QList (if not it is probably similar). So we want to call the 'insert' method.
list.insert(0, item);
And that should be it.
For display you can try delegates as explained in the link (I haven't tried the example though). It will help the community if you can add your observations.
Thanks to everyone for replying. I have found the solution by my own:
In case if anyone is interested
void TableModel::addFile(const QString &path)
{
beginInsertRows(QModelIndex(), list.size(), list.size());
TableItem item;
item.filename = path;
QFile file(path);
item.size = file.size();
item.status = StatusNew;
list << item; // Why Assign first? Maybe not required
for (int i = list.size() - 1; i > 0; i--)
{
list[i] = list[i-1];
}
list[0] = item; // set newly added item at the top
endInsertRows();
}
I want to copy a directory from one drive to another drive. My selected directory contains many sub directories and files.
How can I implement the same using Qt?
void copyPath(QString src, QString dst)
{
QDir dir(src);
if (! dir.exists())
return;
foreach (QString d, dir.entryList(QDir::Dirs | QDir::NoDotAndDotDot)) {
QString dst_path = dst + QDir::separator() + d;
dir.mkpath(dst_path);
copyPath(src+ QDir::separator() + d, dst_path);
}
foreach (QString f, dir.entryList(QDir::Files)) {
QFile::copy(src + QDir::separator() + f, dst + QDir::separator() + f);
}
}
Manually, you can do the next things:
1). with func below you generate folders/files list (recursively) - the destination files.
static void recurseAddDir(QDir d, QStringList & list) {
QStringList qsl = d.entryList(QDir::NoDotAndDotDot | QDir::Dirs | QDir::Files);
foreach (QString file, qsl) {
QFileInfo finfo(QString("%1/%2").arg(d.path()).arg(file));
if (finfo.isSymLink())
return;
if (finfo.isDir()) {
QString dirname = finfo.fileName();
QDir sd(finfo.filePath());
recurseAddDir(sd, list);
} else
list << QDir::toNativeSeparators(finfo.filePath());
}
}
2). then you may to start copying files from destination list to the new source directory like that:
for (int i = 0; i < gtdStringList.count(); i++) {
progressDialog.setValue(i);
progressDialog.setLabelText(tr("%1 Coping file number %2 of %3 ")
.arg((conf->isConsole) ? tr("Making copy of the Alta-GTD\n") : "")
.arg(i + 1)
.arg(gtdStringList.count()));
qApp->processEvents(QEventLoop::ExcludeUserInputEvents);
if (progressDialog.wasCanceled()) {
// removing tmp files/folders
rmDirectoryRecursive(tmpFolder);
rmDirectoryRecursive(tmpFolderPlus);
setEnableGUI(true);
return;
}
// coping
if (!QFile::copy(gtdStringList.at(i), tmpStringList.at(i))) {
if (warningFlag) {
QMessageBox box(this);
QString name = tr("Question");
QString file1 = getShortName(gtdStringList.at(i), QString("\\...\\"));
QString file2 = getShortName(tmpStringList.at(i), QString("\\...\\"));
QString text = tr("Cannot copy <b>%1</b> <p>to <b>%2</b>" \
"<p>This file will be ignored, just press <b>Yes</b> button" \
"<p>Press <b>YesToAll</b> button to ignore other warnings automatically..." \
"<p>Or press <b>Abort</b> to cancel operation").arg(file1).arg(file2);
box.setModal(true);
box.setWindowTitle(name);
box.setText(QString::fromLatin1("%1").arg(text));
box.setIcon(QMessageBox::Question);
box.setStandardButtons(QMessageBox::YesToAll | QMessageBox::Yes | QMessageBox::Abort);
switch (box.exec()) {
case (QMessageBox::YesToAll):
warningFlag = false;
break;
case (QMessageBox::Yes):
break;
case (QMessageBox::Abort):
rmDirectoryRecursive(tmpFolder);
rmDirectoryRecursive(tmpFolderPlus);
setEnableGUI(true);
return;
}
}
}
}
And that's all. Good luck!
I wanted something similar, and was googling (in vain), so this is where I've got to:
static bool cpDir(const QString &srcPath, const QString &dstPath)
{
rmDir(dstPath);
QDir parentDstDir(QFileInfo(dstPath).path());
if (!parentDstDir.mkdir(QFileInfo(dstPath).fileName()))
return false;
QDir srcDir(srcPath);
foreach(const QFileInfo &info, srcDir.entryInfoList(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot)) {
QString srcItemPath = srcPath + "/" + info.fileName();
QString dstItemPath = dstPath + "/" + info.fileName();
if (info.isDir()) {
if (!cpDir(srcItemPath, dstItemPath)) {
return false;
}
} else if (info.isFile()) {
if (!QFile::copy(srcItemPath, dstItemPath)) {
return false;
}
} else {
qDebug() << "Unhandled item" << info.filePath() << "in cpDir";
}
}
return true;
}
It uses an rmDir function that looks pretty similar:
static bool rmDir(const QString &dirPath)
{
QDir dir(dirPath);
if (!dir.exists())
return true;
foreach(const QFileInfo &info, dir.entryInfoList(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot)) {
if (info.isDir()) {
if (!rmDir(info.filePath()))
return false;
} else {
if (!dir.remove(info.fileName()))
return false;
}
}
QDir parentDir(QFileInfo(dirPath).path());
return parentDir.rmdir(QFileInfo(dirPath).fileName());
}
This doesn't handle links and special files, btw.
The hard way. Copy every file individually.
Use QDir::entryList() to iterate over the content of a directory
Use QDir::cd() and QDir::cdUp() to go in and out of directories
Use QDir::mkdir() and QDir::mkpath() to create the new folders tree
and finally, use QFile::copy() to copy the actual files
This is basically petch's answer with a slight change due to it breaking for me in Qt 5.6 (this is the top question hit), so all credit goes to petch.
function
bool copyPath(QString sourceDir, QString destinationDir, bool overWriteDirectory)
{
QDir originDirectory(sourceDir);
if (! originDirectory.exists())
{
return false;
}
QDir destinationDirectory(destinationDir);
if(destinationDirectory.exists() && !overWriteDirectory)
{
return false;
}
else if(destinationDirectory.exists() && overWriteDirectory)
{
destinationDirectory.removeRecursively();
}
originDirectory.mkpath(destinationDir);
foreach (QString directoryName, originDirectory.entryList(QDir::Dirs | \
QDir::NoDotAndDotDot))
{
QString destinationPath = destinationDir + "/" + directoryName;
originDirectory.mkpath(destinationPath);
copyPath(sourceDir + "/" + directoryName, destinationPath, overWriteDirectory);
}
foreach (QString fileName, originDirectory.entryList(QDir::Files))
{
QFile::copy(sourceDir + "/" + fileName, destinationDir + "/" + fileName);
}
/*! Possible race-condition mitigation? */
QDir finalDestination(destinationDir);
finalDestination.refresh();
if(finalDestination.exists())
{
return true;
}
return false;
}
Use:
/*! Overwrite existing directories. */
bool directoryCopied = copyPath(sourceDirectory, destinationDirectory, true);
/*! Do not overwrite existing directories. */
bool directoryCopied = copyPath(sourceDirectory, destinationDirectory, false);
Try this:
bool copyDirectoryFiles(const QString &fromDir, const QString &toDir, bool coverFileIfExist)
{
QDir sourceDir(fromDir);
QDir targetDir(toDir);
if(!targetDir.exists()){ /* if directory don't exists, build it */
if(!targetDir.mkdir(targetDir.absolutePath()))
return false;
}
QFileInfoList fileInfoList = sourceDir.entryInfoList();
foreach(QFileInfo fileInfo, fileInfoList){
if(fileInfo.fileName() == "." || fileInfo.fileName() == "..")
continue;
if(fileInfo.isDir()){ /* if it is directory, copy recursively*/
if(!copyDirectoryFiles(fileInfo.filePath(),
targetDir.filePath(fileInfo.fileName()),
coverFileIfExist))
return false;
}
else{ /* if coverFileIfExist == true, remove old file first */
if(coverFileIfExist && targetDir.exists(fileInfo.fileName())){
targetDir.remove(fileInfo.fileName());
}
// files copy
if(!QFile::copy(fileInfo.filePath(),
targetDir.filePath(fileInfo.fileName()))){
return false;
}
}
}
return true;
}
I have made a library to manipulate files by a shell command style API. It supports a recursively copy of files and handled several more conditions.
https://github.com/benlau/qtshell#cp
Example
cp("-a", ":/*", "/target"); // copy all files from qrc resource to target path recursively
cp("tmp.txt", "/tmp");
cp("*.txt", "/tmp");
cp("/tmp/123.txt", "456.txt");
cp("-va","src/*", "/tmp");
cp("-a", ":resource","/target");
Since I had some trouble with App-Bundles on macOS, here's a solution with QDirIterator
void copyAndReplaceFolderContents(const QString &fromDir, const QString &toDir, bool copyAndRemove = false) {
QDirIterator it(fromDir, QDirIterator::Subdirectories);
QDir dir(fromDir);
const int absSourcePathLength = dir.absoluteFilePath(fromDir).length();
while (it.hasNext()){
it.next();
const auto fileInfo = it.fileInfo();
if(!fileInfo.isHidden()) { //filters dot and dotdot
const QString subPathStructure = fileInfo.absoluteFilePath().mid(absSourcePathLength);
const QString constructedAbsolutePath = toDir + subPathStructure;
if(fileInfo.isDir()){
//Create directory in target folder
dir.mkpath(constructedAbsolutePath);
} else if(fileInfo.isFile()) {
//Copy File to target directory
//Remove file at target location, if it exists. Otherwise QFile::copy will fail
QFile::remove(constructedAbsolutePath);
QFile::copy(fileInfo.absoluteFilePath(), constructedAbsolutePath);
}
}
}
if(copyAndRemove)
dir.removeRecursively();
}
If you are on a linux based system and the cp command exists and can be run, then you can use a QProcess to launch a bash:
auto copy = new QProcess(this);
copy->start(QStringLiteral("cp -rv %1 %2").arg(sourceFolder, destinationFolder));
copy->waitForFinished();
copy->close();
cp details:
-r means recursively
-v means it prints the successfully copied file
Note: if the copy operation is long, then you need to managed the UI freezing, as noted here
Assuming the target location is empty "no existing files or folders
with the same names" and you have no problem to use a Recursive
function!! to copy a directory recursively then the code will be something like this
void copy_all(QString dst_loc, QString src_loc)
{
QDir src(src_loc);
for(QFileInfo file_info : src.entryInfoList(QDir::AllEntries | QDir::NoDotAndDotDot)){
if(file_info.isDir()){
src.mkpath(dst_loc+'/'+file_info.fileName());
copy_all(dst_loc+'/'+file_info.fileName(),file_info.absoluteFilePath());
}
QFile::copy(file_info.absoluteFilePath(), dst_loc+'/'+file_info.fileName());
}
}
if you ever dealt with tree data structures and tried to create a Recursive function to do a "depth-first search" Alogorithm you will get a 85% similar algorithm, which Actually I got this idea from.
The second way, is by using a map data structure to hold the current
fileInfoList in a directory, and the corresponding state to show if
you have used this fileInfo or not yet. and you gather all
information firstly about sub directories and files from the source location.
And this is how most OS and other file managers do to copy data, by showing you the size of files to be copied, how many files and folders are going to be copied, and finally, if there is any conflict of files or folders with the same name before you even initiate copying "if you will do the same algorithm with the destination so that you can match filenames".
Good luck!.