I'm creating a very simple disk space analyzer that shows ocupied size of every file in specific foder and its subfolders. I'm using QStack to store paths and QTableWidget for showing next information (File Name, File Path, File Size and Last Modified Date). First of all I use QDirIterator to fill QStack, then in different thread I get necessary information about file by QFileInfo and add row in QTableWidget with this information. Populating QStack is quick but filling QTableWidget is very slow. The question is how can I boost speed of filling QTableWidget.
dialog.h
#include <QDialog>
#include <QStack>
#include "mythread.h"
namespace Ui {
class Dialog;
}
class Dialog : public QDialog
{
Q_OBJECT
public:
explicit Dialog(QWidget *parent = 0);
~Dialog();
MyThread *mThread;
QStack<QString> *fileStack;
private slots:
void on_pushButton_clicked();
void on_pushButton_2_clicked();
public slots:
void onFileAdded(QString file);
private:
Ui::Dialog *ui;
};
dialog.cpp
#include "dialog.h"
#include "ui_dialog.h"
#include "mythread.h"
#include <QFileDialog>
#include <QDirIterator>
#include <QMessageBox>
#include <QFileInfo>
#include <QDateTime>
Dialog::Dialog(QWidget *parent) :
QDialog(parent),
ui(new Ui::Dialog)
{
ui->setupUi(this);
ui->tableWidget->setColumnCount(4);
ui->tableWidget->setHorizontalHeaderLabels(QStringList() << "File name" << "File Path" << "File Size (KB)" << "Last Modified Date");
fileStack = new QStack<QString>();
ui->tableWidget->setSortingEnabled(true);
mThread = new MyThread(this);
connect(mThread, SIGNAL(fileAdded(QString)), this, SLOT(onFileAdded(QString)));
}
Dialog::~Dialog()
{
delete ui;
delete mThread;
delete fileStack;
}
void Dialog::onFileAdded(QString file) {
QFileInfo fileInfo;
fileInfo.setFile(file);
ui->tableWidget->insertRow(ui->tableWidget->rowCount());
ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1,
0,
new QTableWidgetItem(fileInfo.fileName()));
ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1,
1,
new QTableWidgetItem(fileInfo.filePath()));
int sss = fileInfo.size() / 1024;
QTableWidgetItem *item = new QTableWidgetItem;
item->setData(Qt::EditRole, sss);
ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1,
2,
item);
ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1,
3,
new QTableWidgetItem(fileInfo.lastModified().toString()));
//ui->tableWidget->resizeColumnsToContents();
//ui->tableWidget->resizeRowsToContents();
}
void Dialog::on_pushButton_clicked()
{
QString dirname = QFileDialog::getExistingDirectory(this, tr("Select a Directory"), QDir::currentPath());
ui->lineEdit->setText(dirname);
}
void Dialog::on_pushButton_2_clicked()
{
QDirIterator it(ui->lineEdit->text(), QDir::Files, QDirIterator::Subdirectories);
while (it.hasNext()) {
fileStack->push(it.next());
}
QMessageBox msgBox;
msgBox.setText("Completed");
msgBox.exec();
mThread->dir = fileStack;
mThread->start();
}
Related
I have a specific string on a QLineEdit, this string is passed to a QListView via QPushButton. Those strings are choices of a QComboBox and they are very specific:
1) "[ INFO] Minimum Distance: 5",
2) "[ INFO] Minimum Distance: 10" and
3) "[ INFO] Minimum Distance: 15"
Here a perfectly working minimal verifiable example if you need to test it.
Currently I can successfully change the color of the QGraphicsView but by clicking or double-clicking on the QString entered in the QListView.
The problem: How can I detect the specific QString content inside a QListView in order to change the background color of a QGraphicsView?
What I mean I don't want to click or double-click on the entry of the QListView but I would like the QListView to see that there is a string "[ INFO] Minimum Distance: 5" and therefore change the color of the QGraphicsView automatically without me clicking or double-clicking on the QListView entry.
After I "Go to slot" my choices are the following below:
Below the MVE working code, you can copy /paste on your machine and it will work:
mainwindow.h
#include <QMainWindow>
#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsTextItem>
#include <QStringListModel>
QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = nullptr);
~MainWindow();
void changeColorDetection();
void updateListView();
void updateListView(const QString & message);
private slots:
void on_pushButton_clicked();
void on_listView_entered(const QModelIndex &index);
void on_listView_activated(const QModelIndex &index);
private:
Ui::MainWindow *ui;
QGraphicsView *mView;
QGraphicsScene *mScene;
QGraphicsTextItem *mText;
StringList *newString;
QStringListModel *model;
};
#endif // MAINWINDOW_H
mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
mView = new QGraphicsView();
mScene = new QGraphicsScene();
ui->graphicsView->setScene(mScene);
QFont font;
font.setPixelSize(10);
font.setBold(false);
font.setFamily("Calibri");
mText = new QGraphicsTextItem;
mText->setPos(150,70);
mScene->addText(tr("Boat outside alarm area"))->setDefaultTextColor(Qt::black);
model = new QStringListModel();
ui->listView->setModel(model);
ui->listView->setEditTriggers(QAbstractItemView::NoEditTriggers);
emptyIndex();
connect(ui->listView, SIGNAL(loggingUpdated()), this, SLOT(updateListView(const QString &)));
connect(ui->graphicsView, SIGNAL(clicked(const QModelIndex &)), this, SLOT(on_listView_activated(const QModelIndex &index)));
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::updateListView(const QString & message)
{
if(model->insertRow(model->rowCount())) {
QModelIndex index = model->index(model->rowCount() - 1, 0);
model->setData(index, message);
ui->listView->scrollTo(index);
}
}
void MainWindow::on_pushButton_clicked()
{
QString str = ui->lineEdit->text();
model->insertRow(model->rowCount());
QModelIndex index = model->index(model->rowCount()-1);
model->setData(index, str);
ui->listView->scrollToBottom();
}
void MainWindow::on_comboBox_currentIndexChanged(const QString &arg1)
{
QString list = ui->comboBox->currentText();
ui->lineEdit->setText(list);
Q_UNUSED(arg1)
}
void MainWindow::on_listView_activated(const QModelIndex &index)
{
QStringList allStrings = model->stringList();
QString last = allStrings.last();
if(last.startsWith("[ INFO] Minimum Distance: 5"))
{
ui->graphicsView->setBackgroundBrush(QColor(Qt::red));
}
else if(last.startsWith("[ INFO] Minimum Distance: 10"))
{
ui->graphicsView->setBackgroundBrush(QColor(Qt::yellow));
}
else if(last.startsWith("[ INFO] Minimum Distance: 15"))
{
ui->graphicsView->setBackgroundBrush(QColor(Qt::green));
}
Q_UNUSED(index)
}
EDIT 2
mainwindow.h
#include <QMainWindow>
#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsTextItem>
#include <QStringListModel>
#include "listview.h"
QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = nullptr);
~MainWindow();
public slots:
void setGraphicViewColor(QColor c);
private:
Ui::MainWindow *ui;
QGraphicsView *mView;
QGraphicsScene *mScene;
QGraphicsTextItem *mText;
QStringListModel *model;
ListView *myListView;
};
#endif // MAINWINDOW_H
mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
mView = new QGraphicsView();
mScene = new QGraphicsScene();
ui->graphicsView->setScene(mScene);
QFont font;
font.setPixelSize(10);
font.setBold(false);
font.setFamily("Calibri");
mText = new QGraphicsTextItem;
mText->setPos(150,70);
mScene->addText(tr("Boat outside alarm area"))->setDefaultTextColor(Qt::black);
model = new QStringListModel();
ui->listView->setModel(model);
ui->listView->setEditTriggers(QAbstractItemView::NoEditTriggers);
connect(ui->listView, SIGNAL(changeColor(QColor)), this, SLOT(setGraphicViewColor(QColor)));
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::setGraphicViewColor(QColor c)
{
qDebug() << "Update your graphicsView backgroundBrush" << c;
ui->graphicsView->setBackgroundBrush(Qt::green);
}
listview.h
#ifndef LISTVIEW_H
#define LISTVIEW_H
#include <QListView>
#include <QStringListModel>
class ListView : public QListView
{
Q_OBJECT
public:
ListView(QWidget *parent = nullptr);
signals:
void changeColor(QColor c);
protected:
void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles = QVector<int>()) override;
};
#endif // LISTVIEW_H
listview.cpp
#include "listview.h"
ListView::ListView(QWidget *parent)
: QListView(parent)
{}
void ListView::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles)
{
QListView::dataChanged(topLeft, bottomRight, roles);
/**
* Assuming that you have just one item changed
* So topLeft == bottomRight
*/
if (topLeft.row() == model()->rowCount()-1){
QString last = topLeft.data().toString();
if(last.startsWith("[ INFO] Minimum Distance: 5")) {
emit changeColor(Qt::red);
} else if(last.startsWith("[ INFO] Minimum Distance: 10")) {
emit changeColor(Qt::yellow);
} else if(last.startsWith("[ INFO] Minimum Distance: 15")) {
emit changeColor(Qt::green);
}
}
}
Below the error and a screenshot of the ui that does not detect the change event:
The output of the .ui:
What I have done so far:
I have been doinf a lot of research about this problem and came across this source which was useful but could not solve the problem, but in addition it seems to use a QModelIndex and I am not sure this is exactly what I need for this small project.
Also I read this source which was useful to establish and capture the specific and unique string but in terms of changing colors I could not solve that.
Thank you very much for pointing in the right direction for solving this issue.
If I well understand, you want to change the backgroundBrush of your graphicsView if the last item of your QStringListModel starts with your specific strings.
To detect this, you can subclass QListView:
listview.h:
#ifndef LISTVIEW_H
#define LISTVIEW_H
#include <QListView>
#include <QStringListModel>
class ListView : public QListView
{
Q_OBJECT
public:
ListView(QWidget *parent = nullptr);
signals:
void changeColor(QColor c);
protected:
void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles = QVector<int>()) override;
};
#endif // LISTVIEW_H
listview.cpp:
#include "listview.h"
ListView::ListView(QWidget *parent)
: QListView(parent)
{
}
void ListView::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QVector<int> &roles)
{
QListView::dataChanged(topLeft, bottomRight, roles);
/**
* Assuming that you have just one item changed
* So topLeft == bottomRight
*/
if (topLeft.row() == model()->rowCount()-1){
QString last = topLeft.data().toString();
if(last.startsWith("[ INFO] Minimum Distance: 5")) {
emit changeColor(Qt::red);
} else if(last.startsWith("[ INFO] Minimum Distance: 10")) {
emit changeColor(Qt::yellow);
} else if(last.startsWith("[ INFO] Minimum Distance: 15")) {
emit changeColor(Qt::green);
}
}
}
Now you have all what you need, but you need to add a slot to connect the signal of your custom ListView with your QGraphicsView::brush
// Add this in your mainwindows.h
public slots:
void setGraphicViewColor(QColor c);
// This in the ctor of your MainWindow:
connect(ui->listView, SIGNAL(changeColor(QColor)), this, SLOT(setGraphicViewColor(QColor)));
// And the implementation of your custom slot in mainwindows.cpp
void MainWindow::setGraphicViewColor(QColor c)
{
qDebug() << "Update your graphicsView backgroundBrush" << c;
//ui->graphicsView->setBackgroundBrush(c);
}
I have written a function in Qt to extract the data out of an image for the purpose of manipulating it.
I then have another function to reinsert the data back to an image and display it. The problem I am having is that even if I do no manipulation on the pixel data other than extract and reinsert, it is still changing the data. On a yellow image it changes it to turquoise blue when it should remain yellow.
I am including the function code to extract and reinsert as specimen code. I can include more if it is needed such as the display function etc...Does anyone know if I am doing something wrong?
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
filter = "All Picture Files (*.png *.jpg *.jpeg *.bmp *.tif *.tiff)"
";; Bitmap Files (*.bmp) ;; JPEG (*.jpg *.jpeg) ;; PNG (*.png) ;; TIFF (*.tif *.tiff)";
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::importImage()
{
importCancelled = false;
QString filename = QFileDialog::getOpenFileName(nullptr, QObject::tr("Import Image"), "", filter);
if(!filename.isEmpty()){
image.load(filename);
image = image.convertToFormat(QImage::Format_RGBA8888);
}
else {
importCancelled = true;
if(importCancelled){
QString cleanPlateCancelled = "Operation Cancelled";
ui->statusBar->showMessage(cleanPlateCancelled,5000);
return;
}
}
}
void MainWindow::scaleImage()
{
if (image.isNull()){
return;
}
else {
image = image.scaledToHeight(ui->view->height(), Qt::TransformationMode::SmoothTransformation);
}
}
void MainWindow::displayImage()
{
if (image.isNull()){
return;
}
else {
scene = new QGraphicsScene;
showImage = new QGraphicsPixmapItem(QPixmap::fromImage(image));
scene->addItem(showImage);
ui->view->setScene(scene);
}
}
void MainWindow::rgbaExtraction()
{
numberOfBytes = static_cast<uint>(image.sizeInBytes());
auto const imageData = image.bits();
rgba = std::vector<uchar>(numberOfBytes,0);
rgbaReset = std::vector<uchar>(numberOfBytes,0);
for (uint i{0}; i < numberOfBytes; ++i) {
rgbaReset[i] = rgba[i] = imageData[i];
}
}
void MainWindow::rgbaInsertion()
{
auto *imageData = new uchar[numberOfBytes];
for (uint i{0};i < numberOfBytes;++i) {
imageData[i] = rgba[i];
}
image = QImage(imageData, image.width(), image.height(), QImage::Format_RGBA8888);
}
void MainWindow::on_importButton_clicked()
{
importImage();
scaleImage();
displayImage();
rgbaExtraction();
}
void MainWindow::on_quitButton_clicked()
{
QApplication::quit();
}
void MainWindow::sceneUpdater()
{
showImage->setPixmap(QPixmap::fromImage(image));
scene->update();
ui->view->update();
}
void MainWindow::on_redSlider_valueChanged(int value)
{
QString redString = QString::number(value);
ui->redLabel->setText(redString);
redDelta = value;
colorRed();
rgbaInsertion();
sceneUpdater();
}
mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QDebug>
#include <QImage>
#include <QFileDialog>
#include <string>
#include <QGraphicsScene>
#include <QGraphicsPixmapItem>
QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = nullptr);
~MainWindow();
private slots:
void on_importButton_clicked();
void on_quitButton_clicked();
void on_redSlider_valueChanged(int value);
private:
QGraphicsPixmapItem *showImage;
QGraphicsScene *scene;
QString filter;
QImage image;
bool importCancelled;
QStatusBar *statusBar;
uint numberOfBytes;
std::vector<uchar> rgba;
std::vector<uchar> rgbaReset;
int redDelta{0};
int greenDelta{0};
int blueDelta{0};
int opacityDelta{0};
void importImage();
void scaleImage();
void displayImage();
void rgbaExtraction();
void rgbaInsertion();
void sceneUpdater();
void colorRed(); // Implemented in color.cpp
Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H
color.cpp
#include <mainwindow.h>
void MainWindow::colorRed()
{
for (uint i{0}; i < rgba.size()*sizeof (rgba[i]);i+=4) {
if(rgbaReset[i] + static_cast<uchar>(redDelta)>=255){
rgba[i] = 255;
}
else {
rgba[i] = rgbaReset[i];// + static_cast<uchar>(redDelta);
}
}
}
main.cpp
#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();
}
The problem is in scaleImage(), because scaledToHeight() returns another image format. You may omit the scale operation, or convert the returned image to Format_RGBA8888:
void MainWindow::scaleImage()
{
if (image.isNull()){
return;
}
else {
image = image.scaledToHeight(ui->view->height(), Qt::TransformationMode::SmoothTransformation)
.convertToFormat(QImage::Format_RGBA8888);
}
}
My recomendation is to add some instrumentation after each image manipulation to check that it has the expected format:
qDebug() << Q_FUNC_INFO << "image format:" << image.format();
I create a player for audiobooks - when you open a folder with mp3 file, whole list of them is added to playlist and List View. And i have a Label, which suppose to show duration of the whole book. But player->duration returns only a duration of current track, and if i go through the loop and do playlist->next() every step, player->duration returns 0. I know about Phonon and file metadata, but i need to do this without using it.
I am attaching a source code of a working project, you can use. When the player changes the file, the duration is changed and printed out. To loop within files, there is a need to wait till the decoder completes reading the media file. See the code below and the comments.
This is mainwindow.cpp
#include "mainwindow.h"
#include "mainwindow.h"
#include "ui_mainwindow.h"
bool done =false;
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
player = new QMediaPlayer(this);
playlist = new QMediaPlaylist(player);
playlist->setPlaybackMode(QMediaPlaylist::Sequential);
player->setPlaylist(playlist);
connect(player, &QMediaPlayer::durationChanged, this, &MainWindow::on_durationchanged);
//connect(player,&QMediaPlayer::)
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::on_pushButton_clicked()
{
playlist->addMedia(QUrl::fromLocalFile("Ar_today.mp3"));
playlist->addMedia(QUrl::fromLocalFile("Ar_sunday.mp3"));
playlist->setCurrentIndex(0); //set the first file
while (done == false) //wait till the duration is read
{
QApplication::processEvents();
}
done = false; playlist->setCurrentIndex(1); //change to the second file
while (done == false) //wait till the duration is read
{
QApplication::processEvents();
} //this way you can loop through files
player->setVolume(80);
player->play();
qDebug() << player->errorString();
}
void MainWindow::on_pushButton_2_clicked()
{
player->stop();
}
void MainWindow::on_durationchanged(qint64 duration)
{
done = true;
qDebug() << "duration = " << player->duration();
}
mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QMediaPlayer>
#include <QMediaPlaylist>
#include <QDebug>
extern bool done;
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = nullptr);
~MainWindow();
private slots:
void on_pushButton_clicked();
void on_pushButton_2_clicked();
void on_durationchanged(qint64 duration);
private:
Ui::MainWindow *ui;
QMediaPlayer* player;
QMediaPlaylist* playlist;
};
#endif // MAINWINDOW_H
In the form, create 2 buttons, one called pushbutton to play and the other is pushButton_2 to stop
I created a few QLabel in my MainWindow using Qt Creator and opencv, but I have this error :
error: 'ui' was not declared in this scope
in the function filter_image(). I want to use label to show an image before and after doing some processing.
mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <cv.h>
#include <cxcore.h>
#include <highgui.h>
#include<QImage>
#include<QLabel>
static QImage IplImage2QImage(const IplImage *iplImage) {
int height = iplImage->height;
int width = iplImage->width;
if (iplImage->depth == IPL_DEPTH_8U && iplImage->nChannels == 3)
{
const uchar *qImageBuffer = (const uchar*)iplImage->imageData;
QImage img(qImageBuffer, width, height, QImage::Format_RGB888);
return img.rgbSwapped();
}
else if (iplImage->depth == IPL_DEPTH_8U && iplImage->nChannels == 1)
{
const uchar *qImageBuffer = (const uchar*)iplImage->imageData;
QImage img(qImageBuffer, width, height, QImage::Format_Indexed8);
QVector<QRgb> colorTable;
for (int i = 0; i < 256; i++)
{
colorTable.push_back(qRgb(i, i, i));
}
img.setColorTable(colorTable);
return img;
}
else
{
std::cout << "Image cannot be converted.";
return QImage();
}
}
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
}
MainWindow::~MainWindow() {
delete ui;
}
void MainWindow::changeEvent(QEvent *e)
{
QMainWindow::changeEvent(e);
switch (e->type()) {
case QEvent::LanguageChange:
ui->retranslateUi(this);
break;
default:
break;
}
}
void filter_image(IplImage* img) {
IplImage* roi = cvCreateImage(cvGetSize(img), 8, 3);
cvCvtColor( img, roi, CV_RGB2GRAY );
cvSmooth(img,roi,CV_BLUR, 5, 0, 0, 0);
cvThreshold(roi,roi,100,255,CV_THRESH_BINARY);
IplImage *img_de = cvCloneImage(roi);
QImage qt_i = IplImage2QImage(img_de);
QLabel label_2;
// display on label
ui->label_2->setPixmap(QPixmap::fromImage(qt_i));//error line
// resize the label to fit the image
ui->label_2->resize(ui->label_2->pixmap()->size());
label_2.show();
}
void MainWindow::on_actionOpen_triggered() {
IplImage *frame = cvLoadImage(
QFileDialog::getOpenFileName(this,
"Ouvrir un fichier",
"/../../Fichiers Image",
"Image (*.jpg *.bmp *.jpeg)")
.toStdString().c_str(),3);
IplImage *img_des = cvCloneImage(frame);
QImage qt_im = IplImage2QImage(img_des);
QLabel label;
// display on label
ui->label->setPixmap(QPixmap::fromImage(qt_im));
// resize the label to fit the image
ui->label->resize(ui->label->pixmap()->size());
label.show();
filter_image(frame);
}
mainwindow.h
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow {
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
protected:
void changeEvent(QEvent *e);
public:
Ui::MainWindow *ui;
public slots:
void on_actionOpen_triggered();
};
ui_mainwindow.h
#include <QtCore/QVariant>
#include <QtGui/QAction>
#include <QtGui/QApplication>
#include <QtGui/QButtonGroup>
#include <QtGui/QHeaderView>
#include <QtGui/QLabel>
#include <QtGui/QMainWindow>
#include <QtGui/QMenu>
#include <QtGui/QMenuBar>
#include <QtGui/QStatusBar>
#include <QtGui/QToolBar>
#include <QtGui/QWidget>
QT_BEGIN_NAMESPACE
class Ui_MainWindow{
public:
QAction *actionOpen;
QWidget *centralWidget;
QLabel *label;
QLabel *label_2;
QMenuBar *menuBar;
QMenu *menuFile;
QToolBar *mainToolBar;
QStatusBar *statusBar;
void setupUi(QMainWindow *MainWindow)
{
if (MainWindow->objectName().isEmpty())
MainWindow->setObjectName(QString::fromUtf8("MainWindow"));
MainWindow->resize(600, 400);
actionOpen = new QAction(MainWindow);
actionOpen->setObjectName(QString::fromUtf8("actionOpen"));
centralWidget = new QWidget(MainWindow);
centralWidget->setObjectName(QString::fromUtf8("centralWidget"));
label = new QLabel(centralWidget);
label->setObjectName(QString::fromUtf8("label"));
label->setGeometry(QRect(290, 30, 271, 301));
label_2 = new QLabel(centralWidget);
label_2->setObjectName(QString::fromUtf8("label_2"));
label_2->setGeometry(QRect(20, 20, 281, 331));
MainWindow->setCentralWidget(centralWidget);
menuBar = new QMenuBar(MainWindow);
menuBar->setObjectName(QString::fromUtf8("menuBar"));
menuBar->setGeometry(QRect(0, 0, 600, 21));
menuFile = new QMenu(menuBar);
menuFile->setObjectName(QString::fromUtf8("menuFile"));
MainWindow->setMenuBar(menuBar);
mainToolBar = new QToolBar(MainWindow);
mainToolBar->setObjectName(QString::fromUtf8("mainToolBar"));
MainWindow->addToolBar(Qt::TopToolBarArea, mainToolBar);
statusBar = new QStatusBar(MainWindow);
statusBar->setObjectName(QString::fromUtf8("statusBar"));
MainWindow->setStatusBar(statusBar);
menuBar->addAction(menuFile->menuAction());
menuFile->addAction(actionOpen);
retranslateUi(MainWindow);
QMetaObject::connectSlotsByName(MainWindow);
} // setupUi
void retranslateUi(QMainWindow *MainWindow)
{
MainWindow->setWindowTitle(QApplication::translate("MainWindow", "MainWindow", 0, QApplication::UnicodeUTF8));
actionOpen->setText(QApplication::translate("MainWindow", "Open", 0, QApplication::UnicodeUTF8));
label->setText(QString());
label_2->setText(QString());
menuFile->setTitle(QApplication::translate("MainWindow", "File", 0, QApplication::UnicodeUTF8));
} // retranslateUi};
namespace Ui {
class MainWindow: public Ui_MainWindow {};
} // namespace Ui
The method filter_image, which is where the error is occurring, is not a class method of MainWindow, so it doesn't have access to MainWindow's members (including ui).
You can do a couple of things: if it makes sense, make it part of the MainWindow class. Alternatively, you can pass the ui as a parameter:
void filter_image(Ui::MainWindow* ui, /*other params*/){...}
Also, you are making a local variable label_2 rather than taking the one from the gui.
I want to download the url entered in the line edit widget.
I am not able to get it working , can some one please give me a short code snippet which can put the values of the file to a QString ?
void imdb::on_imdbGetButton_clicked()
{
Qstring link1 = ui->lineEdit2->text();
// QString link1 is the url to be downloaded.
}
I have added , the required header files..
Thanks..
I guess you're trying to download a file via http. Here's what you could do:
In you *.pro file add QT += network
Create an instance of QNetworkAccessManager class;
Supply your file URL to via QNetworkRequest object: manager->get(QNetworkRequest("file_url"));
Connect to the finished signal of the QNetworkAccessManager
In the finished signal handler read the content of the QNetworkReply and save it to the local file.
Below is a small example. Download will start in the button click of the MainForm class:
mainwindow.h:
#include <QMainWindow>
#include <QNetworkAccessManager>
#include <QDebug>
#include <QUrl>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QFile>
#include <QFileInfo>
#include <QPushButton>
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private:
Ui::MainWindow *ui;
QNetworkAccessManager* _manager;
private slots:
void on_pushButton_clicked();
void downloadFinished(QNetworkReply *reply);
};
mainwindow.cpp:
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
QPushButton* button = new QPushButton("Download", this);
button->setGeometry(20, 20, 80, 30);
connect(button, SIGNAL(clicked()), SLOT(on_pushButton_clicked()));
_manager = new QNetworkAccessManager(this);
connect(_manager, SIGNAL(finished(QNetworkReply*)), SLOT(downloadFinished(QNetworkReply*)));
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::on_pushButton_clicked()
{
QUrl url("http://pics.mtii.com/ClassPictures2011/MIA/E110227-PMIA3-JEAN/thumbnails/P2270448%20copy.jpg");
_manager->get(QNetworkRequest(url));
}
void MainWindow::downloadFinished(QNetworkReply *reply)
{
QUrl url = reply->url();
if (reply->error())
{
qDebug() << "Download of " << url.toEncoded().constData()
<< " failed: " << reply->errorString();
}
else
{
QString path = url.path();
QString fileName = QFileInfo(path).fileName();
if (fileName.isEmpty()) fileName = "download";
QFile file(fileName);
if (file.open(QIODevice::WriteOnly))
{
file.write(reply->readAll());
file.close();
}
qDebug() << "Download of " << url.toEncoded().constData()
<< " succeded saved to: " << fileName;
}
}
hope this helps, regards