How to display multiple images on MainWindow??

[CognitiveRobot]

Hi everyone,

i'm new here and stuck.

In my first GUI, I have one push_button which contains certain functions and produces png images after each iteration in a loop. What I'm trying to do is to display those images in QLabel on my mainWindow using code mentioned below....
@
QPixmap myPic(QApplication::applicationDirPath()+"imageName" ); //image1.png, image2.png, image3.png
QLabel *picLabel = new QLabel(ui->label_2);
QPixmap scaledPic(myPic.scaled(ui->label_2->width(),ui->label_2->height()));
picLabel->setPixmap( scaledPic );
picLabel->show();
@
Above code is inside a for loop. The problem is it only displays last image (not one after another).
I'm eagerly waiting for your reply.

Thanks
CogBot

[Edit: Added @ tags around code -- mlong]

[lgeyer]

You will have to add the images to a layout, and then set the layout for <code>ui->label_2</code>. Otherwise the images are just displayed on top of each other.

[CognitiveRobot]

Thanks for your reply. Could you please give me some sample code? I'm very new. Failed to manage.

[lgeyer]

Just pick the most suitable "layout":http://qt-project.org/doc/qt-4.8/layout.html, set it on the label and add the various images to it.

[quote author="CognitiveRobot" date="1340602978"]
@
QHBoxLayout *layout = new QHBoxLayout; // or any other layout
ui->label_2->setLayout(layout);
...
QPixmap myPic(QApplication::applicationDirPath()+"imageName" );
QLabel *picLabel = new QLabel;
QPixmap scaledPic(myPic.scaled(ui->label_2->width(),ui->label_2->height()));
picLabel->setPixmap( scaledPic );
layout->addWidget(picLabel);
@
[/quote]

[CognitiveRobot]

Lukas, thanks again. I couldn't figure it out using layout. But i managed another way. need to add picLabel->repaint() at the end of my mentioned code.

[tesmai4]

I tried to follow your code snippet for displaying all images from a folder. I read all images in QList<QImage> list and then use foreach loop to display.
This code only displays one image. A blank area is displayed for more than one iterations..........
@
QHBoxLayout *layout = new QHBoxLayout; // or any other layout
ui->label_2->setLayout(layout);
...
QPixmap myPic(QApplication::applicationDirPath()+"imageName" );
QLabel *picLabel = new QLabel;
QPixmap scaledPic(myPic.scaled(ui->label_2->width(),ui->label_2->height()));
picLabel->setPixmap( scaledPic );
layout->addWidget(picLabel);
@
Any help is appreciated.

[lgeyer]

Did you put the whole code into your loop, or just the lines after <code>QPixmap myPic(...</code>?

[VRonin]

Try this:
@
QVBoxLayout* PicsLayout=new QVBoxLayout(ui->label_2);
...
//then inside the loop:
QPixmap myPic(QApplication::applicationDirPath()+"imageName" ); //image1.png, image2.png,
QLabel *picLabel = new QLabel(ui->label_2);
picLabel->setScaledContents(true);
picLabel->setPixmap(myPic);
PicsLayout->addWidget(picLabel);
@
You should get all the images in a column.
use QHBoxLayout instead of QVBoxLayout if you want them in a row or QGridLayout if you want them in a grid but, in this case, you should specify the number of column and row for each pic as additional arguments to addWidget

[tesmai4]

thanks VRonin for reply.

@QList<QImage> images;
foreach(QFileInfo fileInfo, filesList)
{
tempFileName += fileInfo.fileName();
QImage image(tempFileName);
copy = image.scaled(inputWidth.toUInt(),inputHeight.toUInt(),Qt::KeepAspectRatio);
images.append(image);
}
//loop correctly populates the list and "images" list has 9 images

QHBoxLayout *verticalPicsLayout=new QHBoxLayout(ui->imageLabel2);
for(int i=0;i<images.size();i++)
{
QPixmap p(QPixmap::fromImage(images[i]));
QLabel *picLabel = new QLabel(ui->imageLabel2);
picLabel->setScaledContents(true);
picLabel->setPixmap(p);
verticalPicsLayout->addWidget(picLabel);
}@

It only shows the first image in list and not all the images....
Am I missing something or doing something incorrectly?

[tesmai4]

Lukas, I posted the code in my recent post, please have a look at it. Any pointer for solving the problem.........
[quote author="Lukas Geyer" date="1357645867"]Did you put the whole code into your loop, or just the lines after <code>QPixmap myPic(...</code>?[/quote]

[tesmai4]

Each image represents thumbnail of a video stream. Next step is to play the video stream by clicking on respective thumbnail.

How will I implement click and play video after displaying the thumbnails from current implementation?

Am I moving in right direction? if not, suggestions are welcome.

[VRonin]

Did you lay out ui->imageLabel2?

I wrote this small test code and the items are shown correctly:

Test.h
@
#ifndef TESTQT_H
#define TESTQT_H
#include <QWidget>
class QLabel;
class TestQt : public QWidget
{
Q_OBJECT
public:
TestQt(QWidget parent = 0);
private:
QLabel MainLabel;
};
#endif
@

Test.cpp
@
#include "testqt.h"
#include <QtGui>

TestQt::TestQt(QWidget parent)
: QWidget(parent)
{
setMinimumSize(100,100);
MainLabel=new QLabel(this);
QHBoxLayout MainLayout=new QHBoxLayout(this);
MainLayout->addWidget(MainLabel);
QHBoxLayout* HorFramesLayout=new QHBoxLayout(MainLabel);
QList<QPixmap> PixList;
for (int i=1;i<=9;i++){
// Generate 9 20x20 pixmap filled with different colours
PixList.append(QPixmap(20,20));
PixList.last().fill(QColor(255i/9,125,125));
}
foreach(QPixmap pix, PixList){
// put the pixmaps one next to the other
QLabel PixLabel=new QLabel(MainLabel);
PixLabel->setScaledContents(true);
PixLabel->setPixmap(pix);
HorFramesLayout->addWidget(PixLabel);
}
}
@

main.cpp
@
#include "testqt.h"
#include <QtGui/QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
TestQt w;
w.show();
return a.exec();
}
@

Hope this example helps

[VRonin]

ok, I think i spotted the problem.
@tempFileName += fileInfo.fileName();@
should become
@tempFileName = fileInfo.fileName();@

You are just concatenating the filenames and the QImage constructor just uses the first one

[tesmai4]

Thanks for the correction, it works.

[quote author="VRonin" date="1357663085"]ok, I think i spotted the problem.
@tempFileName += fileInfo.fileName();@
should become
@tempFileName = fileInfo.fileName();@

You are just concatenating the filenames and the QImage constructor just uses the first one[/quote]