I am currently writing an application in Qt, which is basically a warehouse. An application reads CSV, enables user to process it and enables to show picture of each good. I tried displaying picture using QLabel and Pixmap, however nothing happens even though the file is in the same folder and the name provided is exactly as it should be. Is it the resources issue or my code fails somehow? Is there any possibility to display the image without adding it to resources in order to avoid adding many photos manually?
void ImageViewer::viewImage(QString imgName)
{
QString pathWithName = imgName;
pathWithName.append(".jpg");
ui->label->setPixmap( QPixmap(pathWithName) );
ui->label->show();
update();
}
Sorry for any mistakes in post creation or code displaying here- it's my first post.
Edit:
I am adding code from MainWindow (called CsvReader in my project) to how I'm invoking the method viewImage:
void CsvReader::on_imgView_clicked()
{
ImageViewer* img = new ImageViewer(this);
img->setModal(true);
img->exec();
QModelIndex List selInd ui->tableView->selectionModel()->selectedIndexes();
QString id = model->item(selInd.first().row(), 0)->text();
img->viewImage(id);
}
Edit 2:
Solved. Had to change path using QDir:
QDir* directory = new QDir("/home/kokos/Magazyn/photos");
QFileInfo checkFile(*directory, pathWithName);
Thanks in advance,
Kokos
Confirm your file's location and existence first. Add this;
QFileInfo checkFile(pathWithName);
if (checkFile.exists() && checkFile.isFile()) {
// your code
}
Related
just started using qt,
looked through docs, google, examples, etc.. trying to find simple examples(working mind you)
that showed how to do (imho) simple things, by themselves.
well i stumbled upon my answer and i was wondering if this approach would cause an issue later as the code becomes more complex.
there are more includes than needed for this example, but this is direct from working code.
mainwindow.h:
i added
private slots:
void vpkButton_clicked();
and after
Ui::MainWindow *ui;
i added
QLineEdit *vpkPathTxt;
in mainwindow.cpp:
after
ui->setupUi(this);
i added
connect( this->ui->vpkButton, SIGNAL( clicked() ), this, SLOT(vpkButton_clicked()) );
to connect my ui button to the proper slot, the issue was getting the string from vpkButton_clicked() to display in the line edit i made in the designer,
what ended up working for me was adding this next:
vpkPathTxt = this->ui->vpkPathTxt;
the function in my main.cpp became very easy:
(QString declarations at top outside voids)
void MainWindow::vpkButton_clicked()
{
vpkName = QFileDialog::getOpenFileName(this,
tr("Open VPK File"), "~/", tr("VPK Files (*_dir.vpk)"));
vpkPathTxt->setText(vpkName);
qDebug() << vpkName;
}
the reason i am ask is because it seems a little too easy to be reliable, and the fact that i havent seen it done like this,
any input welcome
thankyou
One problem with your slot is that you don't consider the case where the user discards the "open file" dialog. In this case, the function QFileDialog::getOpenFileName returns a null QString, so you should only proceed with your logic if the return value was not a null string:
if (!vpkName.isNull()) {
...
}
The second problem is as follows and I made some assumptions since I don't see your full code:
I guess you want to load a file using the file name the user has chosen in the dialog. But you set the file name in the line edit too, which the user can edit by hand. I also guess that the actual file loading happens in a different step (i.e. after clicking another button), so after the user has edited the file name by hand in the line edit it won't be the same than in your local variable vpkName.
When loading the file I'd read the contents of the line edit instead of the variable vpkName so the edit made by hand will be respected.
A different method is to also watch for editing of the line edit and reflect the changes in your variable too. Then it will be ok to read the variable instead of the line edit when loading the file later on.
I wrote this on official forums of Qt, but it seems dead, so I am going to copy-paste it here.
I am writing small program for copying files. I use QTreeView and I have inherited from QFileSystemModel, so I was able to add checkboxes to every row in the QTreeView. I also use setNameFilters method connected with QLineEdit, so user can specify what file extensions he wants to display in the QTreeView. I have spotted the following behavior:
1) When I run the program and enter extensions to filter (without touching any node from the QTreeView) everything works fine and files with extensions I have provided are only displayed (and folders of course). When I change the extensions and the view is refreshed, on my "C:/" drive everything is updated and only new set of extensions is displayed. When I expand some other drive that I didn’t touch before, it also shows files correctly.
2) When I run the program and expand let say my "C:/" and "D:/" drives I see all directories and files (expected behavior). Then I write some extensions and the view is refreshed. I expand "C:/" drive and everything works fine, only files with extensions I have provided are displayed. Then I go to "D:/" drive and here is the problem. It displays all files. It ignores the filters I have provided. When I open the "E:/" drive that I have not opened before, the files are filtered correctly as in "C:/" drive.
I have concluded, that this behavior has something to do with setRootPath method, because for my QTreeView only in "C:/" drive the filters are working correctly. All other drives that were expanded before change of filters don’t work. Those not expanded work just fine.
The question is: How to get this working, so after user changes the filters and reset() method is fired, the whole QTreeView is refreshed and not only root path and not-expanded elements? Maybe there exists some root path that have all the drives as children and it will work as expected? Or maybe I should make some virtual folder in the QTreeView called "MyComputer" and set it to be a parent for all the drives? But how to get list of all the available drives?
I hope that what I wrote is clear for you and you can help me to get this working.
Edit:
Adding some code that is relevant. If you need more just ask.
//setting up the model and view
QString rPath = "C:/";
rTree_model = new TreeModel(this); //TreeModel inherits from QFileSystemModel
rTree_model->setRootPath(rPath);
ui->rTree->setModel(rTree_model); //applies the model for the qtreeview (ui->rTree)
//(...)
//action when extensions were provided by user
QString extensions = QString(ui->extensionBox->text()); //gets extensions provided by user
QStringList filters;
if(extensions.length() > 0) {
filters = extensions.split(";", QString::SkipEmptyParts); //splits extensions provided with ';' as separator
rTree_model->setNameFilters(filters); //applies filters
ui->rTree->reset(); //resets the view
}
Try changing your root path to My Computer instead of C:/. It seems to work with QFileSystemModel in Windows 7 x64 and Qt 4.8.2, but I can't guarantee anything for other platforms.
rTree_model = new TreeModel(this);
QString rPath = model->myComputer().toString(); //causes the QFileSystemWatcher to watch every drive?
rTree_model->setRootPath(rPath);
ui->rTree->setModel(rTree_model);
Well I have been working on a Qt app where I need to display Filesystem using QFilesystemModel.I have been able to display it as expected.
Code:
QFileSystemModel *model = new QFileSystemModel;
model->setRootPath(QDir::currentPath())
tree->setModel(model);
This displays all drives inside QTreeView. But we all know by default, the color of the folders present inside each drive is yellow.
This is what i wanna change. Is there a way in Qt, where one can change the color of folder to "Blue"???
You can customize your QTreeView via a qt delegate. But if it is just for an icon, I think you can reimplement:
class MyQFileSystemModel : public QFileSystemModel {
public:
QVariant data( const QModelIndex& index, int role ) const {
if( role == Qt::DecorationRole ) {
return QVariant(QIcon(QPixmap("icon.png")));
}
return QFileSystemModel::data(index, role);
}
};
To learn about delegate, I suggest you study the examples: Spin box delegate
EDIT: you have to reimplement the method data from a QFileSystemModel, you must inherit from QFileSystemModel.
Then you do as before:
MyQFileSystemModel* model = new MyQFileSystemModel;
model->setRootPath(QDir::currentPath())
tree->setModel(model);
I would assume that the workaround is to use your own fileIcon.
Qt uses whatever the default icon is for the current platform. I'm guessing you're on Windows.
This question provides some clues on how to implement.
(I just started learning Qt myself, BTW!)
I am a student programmer using Qt to build a reader Table for my company. This reader is both an editor and converter. It reads in a .i file allows table editing of a text document and then puts out a .scf file which is essentially a separated value file stacked under a legend built with headers. I digress... Basically the file format imported is really hard to scan and read in(mostly impossible) so what I'd like to is modify the open file preBuilt QFileDialog to include an additional drop down when older file types are selected to declare their template headers.
When the user selects .i extension files(option 2 file type) I would like to enable an additional drop down menu to allow the user to select which type of .i file it is(template selected). This way I don't have to deal with god knows how many hours trying to figure out a way to index all the headers into the table for each different type. Currently my importFile function calls the dialog using this:
QString fileLocation = QFileDialog::getOpenFileName(this,("Open File"), "", ("Simulation Configuration File(*.scf);;Input Files(*.prp *.sze *.i *.I *.tab *.inp *.tbl)")); //launches File Selector
I have been referencing QFileDialog Documentation to try and find a solution to what I need but have had no avail. Thanks for reading my post and thanks in advance for any direction you can give on this.
UPDATE MAR 16 2012;
First I'd like to give thanks to Masci for his initial support in this matter. Below is the connect statement that I have along with the error I receive.
//Declared data type
QFileDialog openFile;
QComboBox comboBoxTemplateSelector;
connect(openFile, SIGNAL(currentChanged(const &QString)), this, SLOT(checkTemplateSelected()));
openFile.layout()->addWidget(comboBoxTemplateSelector);
I also noticed that it didn't like the way I added the QComboBox to the modified dialog's layout(which is the second error). I really hope that I'm just doing something dumb here and its an easy task to overcome.
In response to tmpearce's comment heres my header code;
#include <QWidget>
namespace Ui {
class ReaderTable;
}
class ReaderTable : public QWidget
{
Q_OBJECT
public:
explicit ReaderTable(QWidget *parent = 0);
~ReaderTable();
public slots:
void checkTemplateSelected();
void importFile();
void saveFile();
private:
Ui::ReaderTable *ui;
};
Thanks for reading and thanks in advance for any contributions to this challenge!
Instance a QFileDialog (do not call getOpenFileName static method), access its layout and add a disabled QComboBox to it.
// mydialog_ and cb_ could be private fields inside MyClass
mydialog_ = new QFileDialog;
cb_ = new QComboBox;
cb_->setEnabled(false);
connect(mydialog, SIGNAL(currentChanged(const QString&)), this, SLOT(checkFilter(const QString&)));
mydialog_->layout()->addWidget(cb_);
if (mydialog_->exec() == QDialog::Accepted) {
QString selectedFile = mydialog_->selectedFiles()[0];
QString cbSelection = cb_->currentText();
}
the slot would be something like:
void MyClass::checkFilter(const QString& filter)
{
cb_->setEnabled(filter == "what_you_want");
}
returning from the dialog exec(), you could retrieve selected file and cb_ current selection.
Notice you could add something more complex than a simple QComboBox at the bottom of the dialog, taking care of gui cosmetics.
Actually I don't like very much this approach (but that was what you asked for :-). I would make a simple dialog like this:
and enable the combo only if the selected file meets your criteria. The "browse" button could call getOpenFileMethod static method in QFileDialog.
You can handle item selection by this signal:
void QFileDialog::fileSelected ( const QString & file )
Then it occurs, call setFilter with type you want.
Sorry, if i don't understand your task.
I am using QT to create a chat messenger client. To display the list of online users, I'm using a QListWidget, as created like this:
listWidget = new QListWidget(horizontalLayoutWidget);
listWidget->setObjectName("userList");
QSizePolicy sizePolicy1(QSizePolicy::Preferred, QSizePolicy::Expanding);
sizePolicy1.setHorizontalStretch(0);
sizePolicy1.setVerticalStretch(0);
sizePolicy1.setHeightForWidth(listWidget->sizePolicy().hasHeightForWidth());
listWidget->setSizePolicy(sizePolicy1);
listWidget->setMinimumSize(QSize(30, 0));
listWidget->setMaximumSize(QSize(150, 16777215));
listWidget->setBaseSize(QSize(100, 0));
listWidget->setContextMenuPolicy(Qt::CustomContextMenu);
Users are shown by constantly refreshing the list, like this: (Note: There are different channels, with different userlists, so refreshing it is the most efficient thing to do, as far as I know.)
void FMessenger::refreshUserlist()
{
if (currentPanel == 0)
return;
listWidget = this->findChild<QListWidget *>(QString("userList"));
listWidget->clear();
QList<FCharacter*> charList = currentPanel->charList();
QListWidgetItem* charitem = 0;
FCharacter* character;
foreach(character, charList)
{
charitem = new QListWidgetItem(character->name());
// charitem->setIcon(QIcon(":/Images/status.png"));
listWidget->addItem(charitem);
}
}
This has always worked perfectly. The line that I commented out is the one I have problems with: my current goal is to be able to display a user's online status with an image, which represents whether they are busy, away, available, etc. Using setIcon() does absolutely nothing though, apparently; the items still show up as they used to, without icons.
I'm aware that this is probably not the way this function needs to be used, but I have found little documentation about it online, and absolutely no useful examples of implementations. My question is, can anybody help me with fixing this problem?
This is how you may conduct your debugging:
Try the constructor that has both icon and text as arguments.
Try to use that icon in another context to ensure it is displayable (construct a QIcon with same argument and use it elsewhere, e.g. QLabel!).
Use icon() from the QListWidgetItem to receive back the icon and then look at that QIcon.
Create a new QListWidget, change nothing, and ordinarily add some stock items in your MainWidget's constructor. See if the icons show up there.