I have some pictures in the resource file and their file names correspond to their staffIds. this is how I set the picture into my QLabel but nothing is shown.
QString staffId;
staffId=ui->lineEdit_staffID->text();
QPixmap managerPic(":/staff/\'"+staffId+"\'.jpg");
managerInterface.ui->label_mpic->setScaledContents(true);
managerInterface.ui->label_mpic->setPixmap(managerPic);
I'm with #Mike here, most probably the single quotes aren't part of your filenames. You can use the debugger to see what is passed to the QPixmap constructor, or put the name into a separate QString variable and write it to qDebug() to see what it contains.
In general you better use QString::arg() to build strings instead of concatenation; usually it's easier to read and understand:
QPixmap managerPic(QString(":/staff/\'%1\'.jpg").arg(staffId));
QPixmap managerPic(QString(":/staff/%1.jpg").arg(staffId));
Related
I'm trying to read and edit a Desktop Entry .desktop file using Qt QSettings. The problem is that these files contain keys with multiple values separated by semicolon ;. I tried reading these as QStringList but no luck. I only get the first value. For example:
Keywords=disc;cdrom;dvd;burn;audio;video;
Categories=GTK;GNOME;AudioVideo;Audio;Video;DiscBurning;
MimeType=application/x-cd-image;application/x-cdrdao-toc;application/x-cue;application/x-toc;audio/x-scpls;audio/x-ms-asx;audio/x-mp3-playlist;audio/x-mpegurl;application/x-brasero;x-content/audio-cdda;x-content/video-dvd;x-content/video-vcd;x-content/video-svcd;x-content/image-picturecd;
Getting the values with:
settings.value("Desktop Entry/MimeType").toStringList();
settings.value("Desktop Entry/MimeType").toString();
returns only the first value (in my example: disc, GTK or application/x-cd-image).
How to I return the full value from those keys? And how do I write it back using QSettings?
Update (first attempt was completely useless)
Variant 1
QMap<QString, QString> settings;
QFile inFile("<input filename.ini>");
if(inFile.open(QIODevice::ReadOnly))
{
QTextStream in(&inFile);
while (!in.atEnd())
{
QString line = in.readLine();
QStringList linelist = line.split("=");
settings[linelist[0]] = linelist[1];
}
}
Variant 2
use QSettings::registerFormat().
This is probably the only "clean" way to do it with QSettings. The advantage is that you can register it with the .desktop extension. You'll have to write a pair of ReadFunc() and WriteFunc() functions.
I think you can't do it. QSettings has certain interpretation of .ini file format, which is very close to Windows interpretation, and is not meant for generic parsing. Semicolon starts a comment, and apparently QSettings allows comment after value until end of line, and AFAIK there's no way around it.
You need to find a different library to handle .desktop files, or implement one yourself.
Is there a way to find out the filename of a QPixmap? My intention was to test which pixmap is currently set.
I've tried Squish to find out any properties, but I've get only access to some stuff like width, height etc
I assume that while you writing a test you already know which image you want to see. You can convert QPixmap to QImage and check if it contains the same image as expected:
bool same = QImage(filename) == pixmap.toImage();
It's not efficient but should be ok for testing purposes.
I have a GUI application whose main part is a QPlainTextEdit. It is used to display a log of the application, and as such the associated text grows line by line ad infinitum.
As the application is intended to run very long, I need to limit the memory that will be allocated for this log. Therefore I want to have some maxNumLines or maxNumCharacters parameter that will make sure the history will be truncated when reached, i.e. the head lines will be removed as new lines are appended (a.k.a. log rotation).
To achieve this I found the functions
// get the associated text
QString toPlainText () const
// set the associated text
void setPlainText ( const QString & text )
Therefore something like this untested code would probably do the trick:
QString &tmp = pte.toPlainText();
while (tmp.size() > maxNumCharacters) {
// remove lines from the head of the string until the desired size is reached
// removes nothing if "\n" could not be found
tmp.remove(0, tmp.indexOf("\n")+1);
}
pte.setPlainText( tmp );
Is this the way to go to remove the first line(s) from the QPlainTextEdit? Are there probably other Qt Text GUI elements that would better fit to this task (set a maximum number of lines and truncate at the head of the list), e.g. somehow display a QStringList in which I could store the lines (s.t. I could easily erase(0))?
Or does the QPlainTextEdit eventually implement such upper bound for the size of the associated QString after all?
Apparantly the property maximumBlockCount is exactly what I need:
If you want to limit the total number of paragraphs in a QPlainTextEdit, as it is for example useful in a log viewer, then you can use the maximumBlockCount property. The combination of setMaximumBlockCount() and appendPlainText() turns QPlainTextEdit into an efficient viewer for log text.
For reference:
http://doc.qt.io/qt-5/qplaintextedit.html#maximumBlockCount-prop
I had exactly the same problem a months back, and I ended up using a QListView. Although using the model/view/delegate architecture is a bit more fiddly, it scales much better in the long run. For example once the basic architecture is in place, adding a filter that displays only error or warning entries becomes trivial, or creating a delegate so that the background of error entries are painted red is also straightforward.
when dragging a file from path
\\Nearlinestorage\anc\sequences\anc_SH_005\2d\cgRenders\Maya_Files\28.07.11
in lineEdit area it cuts \\nearlinestorage when reading ui->lineedit->text()
how is it possible to get the whole path
solved. Problem is in the droparea::dropevent(QDropEvent *event).
I replaced
QString url = urlList.at(i).path();
with
QString url = urlList.at(i).toLocalFile();
I get proper result ( as expected ).
Make sure the QLineEdit doesn't have a minimum number of characters set.
I encountered a problem with passing Image object (captured with Point Grej FlyCapture2 SDK) to QImage object. I am getting a pointer associated with Image data by function:
virtual unsigned char* FlyCapture2::GetData ( )
and then loading the data by:
QImage::QImage ( uchar * data, int width, int height, int bytesPerLine, Format format )
Formats of data of both Image objects are 8-bit monocolor. BytesPerLine parameter should be equal to width of the Image (I've already checked it by saving FlyCapture2::Image to .bmp and then loading it to QImage).
Do you thing the problem is casting from unsigned char* to uchar*?
Do you have any other ideas? Copying image pixel by pixel is much too slow.
EDIT: I am converting Image captured by FlyCapture into the FlyCapture2::PIXEL_FORMAT_RGB8 , for which: R = G = B = 8 bits, within PGR::SnapShot() function. SnapShot() returns unsigned char* const.
and here is a part of my Qt display function:
unsigned char *const img = PGRSystem->SnapShot();
QImage Img(img, 1024, 768, QImage::Format_RGB888);
QGraphicsScene *Scene = new QGraphicsScene();
Scene->addPixmap(QPixmap::fromImage(Img));
ui.ImageView->setScene(Scene);
ui.ImageView->fitInView(ui.ImageView->itemAt(100,100));
delete [] Scene;
I also tried to save Img to file, but got unhandled exception then. I tried other pixel format pairs (FlyCapture2::PIXEL_FORMAT_RGB - 24 bit RGB with QImage::RGB888 and FlyCapture2::PIXEL_FORMAT_RGBU32 with QImage::RGB32)
It is also worth to mention that QImage constuctor, which I am using, does not set the colorTable (I am getting exception when checking if QImage is in grayScale).
I need a little more help I guess.
First thing - QImage doesn't support a native greyscale image, which is what it sounds as if you're getting as output - so I would be curious what Format argument you're using. Probably the easiest solution, though memory-inefficent, will be to expand your greyscale image to RGB by copying each value three times (into a new QByteArray).
An additional concern is that the particular QImage constructor you're using, does not copy the underlying data, so you need be sure the pointer returned from GetData() outlives the QImage - or force the QImage to make a copy internally, using, say, QImage::copy.
Seeing more code would help, as other respondents noted above.
Thanks a lot for your help, you were right about the Image formats. Unfortunatelly the main problem was associated with passing the pointer between functions. In PGR::SnapShot() I was creating FlyCapture2::Image and then I was getting the pointer to data. FlyCapture2::Image was detructed when exit the function so returned pointer was BadPtr.