I wrote a web service with PHP. I need download content via web service URL. How can I download data from URL?
Which libraries are needed?
Add QT += network in .pro project file
Include below libraries to your code:
#include <QUrl>
#include <QtNetwork/QNetworkAccessManager>
#include <QtNetwork/QNetworkRequest>
#include <QtNetwork/QNetworkReply>
At the end receive URL content via following code:
QString url = "WEB_SERVICE_URL";
QNetworkAccessManager manager;
QNetworkReply *response = manager.get(QNetworkRequest(QUrl(url)));
QEventLoop event;
connect(response, SIGNAL(finished()), &event, SLOT(quit()));
event.exec();
QString content = response->readAll();
Related
I have 4 qml files and one main.cpp to load qml file.
Is it possible for me to create 1 dll file for those 4 qml file.
And use it in different application if so how to do that.
As already said, there is no need for embedding qml files only in a library. But of course you have the right to do all you want, even that. I know at least 2 ways to do that:
1. Create binary resource file
Prepare resource file containing qml files and then compile it:
rcc -binary plugin.qrc -o plugin.rcc
Now you can include this file into your application :
QResource::registerResource("plugin.rcc");
and use it as regular qrc file:
QResource::registerResource(qApp->applicationDirPath() + "/plugin.rcc");
QQuickView *view = new QQuickView();
view->setSource(QUrl("qrc:/qml/myfile.qml"));
Here qml/ is prefix in resource file.
2. Shared libraryAnother way is to create a shared library containing the same resource file. For example your plugin's shared library implements following interface:
interface.h
#ifndef PLUGIN_INTERFACE_H
#define PLUGIN_INTERFACE_H
#include <QString>
#include <QObject>
class PluginInterface
{
public:
virtual ~PluginInterface() {}
virtual QByteArray getQML(const QString &name) = 0;
};
#define PluginInterface_iid "org.qt-project.PluginInterface"
Q_DECLARE_INTERFACE(PluginInterface, PluginInterface_iid)
#endif
and its implementation is:
QByteArray PluginImpl::getQML(const QString &name)
{
QFile file(":/qml/" + name);
if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
return QByteArray();
return file.readAll();
}
Now, in your application you load your plugin and get its resource as a string:
QDir pluginsDir(qApp->applicationDirPath());
QPluginLoader pluginLoader(pluginsDir.absoluteFilePath("plugin.dll"));
QObject *plugin = pluginLoader.instance();
if (plugin) {
PluginInterface *pluginInstance = qobject_cast<PluginInterface *>(plugin);
if (pluginInstance) {
QByteArray content = pluginInstance->getQML("file1.qml");
QQuickView *view = new QQuickView();
QQmlComponent component(view->engine());
component.setData(content, QUrl());
QQuickItem *childItem = qobject_cast<QQuickItem*>(component.create());
childItem->setParentItem(view->contentItem());
QWidget *container = QWidget::createWindowContainer(view);
container->setFocusPolicy(Qt::TabFocus);
ui->verticalLayout->addWidget(container);
}
}
But pay attention, when you deploy your application you anyway have to copy all qml system files, like #QTPATH/qml/QtQml, #QTPATH/qml/QtQuick.2, #QTPATH/qml/QtQuick.2 etc.
Links:
Resource compiler
Same theme
Plugin example
Have a look at the documentation for QML Modules
There are options for QML-only modules, C++ only and mixed mode.
I have 4 qml files and one main.cpp to load qml file.
Is it possible for me to create 1 dll file for those 4 qml file.
And use it in different application if so how to do that.
As already said, there is no need for embedding qml files only in a library. But of course you have the right to do all you want, even that. I know at least 2 ways to do that:
1. Create binary resource file
Prepare resource file containing qml files and then compile it:
rcc -binary plugin.qrc -o plugin.rcc
Now you can include this file into your application :
QResource::registerResource("plugin.rcc");
and use it as regular qrc file:
QResource::registerResource(qApp->applicationDirPath() + "/plugin.rcc");
QQuickView *view = new QQuickView();
view->setSource(QUrl("qrc:/qml/myfile.qml"));
Here qml/ is prefix in resource file.
2. Shared libraryAnother way is to create a shared library containing the same resource file. For example your plugin's shared library implements following interface:
interface.h
#ifndef PLUGIN_INTERFACE_H
#define PLUGIN_INTERFACE_H
#include <QString>
#include <QObject>
class PluginInterface
{
public:
virtual ~PluginInterface() {}
virtual QByteArray getQML(const QString &name) = 0;
};
#define PluginInterface_iid "org.qt-project.PluginInterface"
Q_DECLARE_INTERFACE(PluginInterface, PluginInterface_iid)
#endif
and its implementation is:
QByteArray PluginImpl::getQML(const QString &name)
{
QFile file(":/qml/" + name);
if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
return QByteArray();
return file.readAll();
}
Now, in your application you load your plugin and get its resource as a string:
QDir pluginsDir(qApp->applicationDirPath());
QPluginLoader pluginLoader(pluginsDir.absoluteFilePath("plugin.dll"));
QObject *plugin = pluginLoader.instance();
if (plugin) {
PluginInterface *pluginInstance = qobject_cast<PluginInterface *>(plugin);
if (pluginInstance) {
QByteArray content = pluginInstance->getQML("file1.qml");
QQuickView *view = new QQuickView();
QQmlComponent component(view->engine());
component.setData(content, QUrl());
QQuickItem *childItem = qobject_cast<QQuickItem*>(component.create());
childItem->setParentItem(view->contentItem());
QWidget *container = QWidget::createWindowContainer(view);
container->setFocusPolicy(Qt::TabFocus);
ui->verticalLayout->addWidget(container);
}
}
But pay attention, when you deploy your application you anyway have to copy all qml system files, like #QTPATH/qml/QtQml, #QTPATH/qml/QtQuick.2, #QTPATH/qml/QtQuick.2 etc.
Links:
Resource compiler
Same theme
Plugin example
Have a look at the documentation for QML Modules
There are options for QML-only modules, C++ only and mixed mode.
I have implemented a code that creates a zip file. The zip file gets successfully created but however when I manually (without code) try and check the contents of the zip file by unzipping it, I get an error saying No archive found and the unzipping process stops.. Why is this problem occuring.
Here is my code
#include <QCoreApplication>
#include <QByteArray>
#include <QBitArray>
#include <QString>
#include <QDebug>
#include <QFile>
void Zip(QString filename , QString zipfilename);
int main(int argc, char *argv[]){
QCoreApplication a(argc, argv);
Zip("C:\\programs\\zipping_qt\\sample.txt",
"C:\\programs\\zipping_qt\\samples.zip");
qDebug() << "Done zipping";
return a.exec();
}
void Zip (QString filename , QString zipfilename){
QFile infile(filename);
QFile outfile(zipfilename);
infile.open(QIODevice::ReadOnly);
outfile.open(QIODevice::WriteOnly);
QByteArray uncompressedData = infile.readAll();
QByteArray compressedData = qCompress(uncompressedData,9);
outfile.write(compressedData);
infile.close();
outfile.close();
}
qCompress does not create zip files. It uses zlib to create a compressed data block. Such blocks can only be directly decompressed by using qUncompress, or by calling zlib directly. There's no standard stand-alone utility that does such decompression. Not even gunzip does it, since zlib-style API uses different headers than gzip.
There are some other nitpicks about your code:
There's no need to call a.exec() if you don't need to run the event loop.
There's no need to explicitly close the files, since QFile is a proper C++ class and implements RAII.
You never check if open, readAll or write succeeds.
I am having problems with launching Nokia's own video player from my application that I just don't seem to be able to solve.
My first attempt included calling
Qt.openUrlExternally(url)
from QML and that seemed to do the trick just fine, except that it opened the browser every time and used it instead of the video-suite (native player).
Next I tried cuteTube -approach where I start new process like this:
QStringList args;
args << url;
QProcess *player = new QProcess();
connect(player, SIGNAL(finished(int, QProcess::ExitStatus)), player, SLOT(deleteLater()));
player->start("/usr/bin/video-suite", args);
That worked, except that it required video-suite to be closed upon calling player->start, otherwise it did nothing.
My third attempt involved starting the video-suite via QDBus, but that didn't work any better:
QList<QVariant> args;
QStringList urls;
urls << url;
args.append(urls);
QDBusMessage message = QDBusMessage::createMethodCall(
"com.nokia.VideoSuite",
"/",
"com.nokia.maemo.meegotouch.VideoSuiteInterface",
"play");
message.setArguments(args);
message.setAutoStartService(true);
QDBusConnection bus = QDBusConnection::sessionBus();
if (bus.isConnected()) {
bus.send(message);
} else {
qDebug() << "Error, QDBus is not connected";
}
The problem with this is that it requires video-suite to be up and running - autoStartService parameter didn't help either. If video-suite isn't running already, the call opens it just fine but, alas, no video starts to play.
Eventually I tried using also VideoSuiteInterface, but even having the program compile with it seemed to be difficult. When I eventually managed to compile and link all relevant libraries, the results didn't differ from option 3 above.
So, is there a way to use either VideoSuiteInterface directly or via DBus so that it would start video playback regardless of the current state of the application?
The solution was actually simpler than I really thought initially; the VideoSuiteInterface -approach worked after all. All it took was to use it properly. Here are the full sources should anyone want to try it themselves.
player.h:
#ifndef PLAYER_H
#define PLAYER_H
#include <QObject>
#include <maemo-meegotouch-interfaces/videosuiteinterface.h>
class Player : public QObject {
Q_OBJECT
private:
VideoSuiteInterface* videosuite;
public:
Player(QObject *parent = 0);
Q_INVOKABLE void play(QString url);
};
#endif // PLAYER_H
player.cpp:
#include "player.h"
#include <QObject>
#include <QStringList>
#include <QtDeclarative>
Player::Player(QObject *parent) : QObject(parent) {}
void Player::play(QString url) {
QList<QVariant> args;
QStringList urls;
urls << url;
args.append(urls);
videosuite = new VideoSuiteInterface();
videosuite->play(urls);
}
In addition you may want to connect some signals to make the UI more responsive, but basically that should do the trick.
Finally, you need to remember to add following to your .pro file and you are good to go:
CONFIG += videosuiteinterface-maemo-meegotouch
Can anyone tell me how to play video from phone memory??
EDITED :i have use this code for video Playing...
include "playvideo.h"
include "ui_playvideo.h"
include QFileDialog
include phonon/backendcapabilities.h
include phonon/videoplayer
include "mainwindow.h"
PlayVideo::PlayVideo(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::PlayVideo)
{
ui->setupUi(this);
videoPlay();
}
void PlayVideo::videoPlay()
{
QString fileName = QFileDialog::getOpenFileName(this, tr("Open Movie"), QDir::homePath());
Phonon::VideoPlayer *player = new Phonon::VideoPlayer(Phonon::VideoCategory,ui->graphicsView );
connect(player, SIGNAL(finished()), player, SLOT(deleteLater()));
player->play(fileName);
}
but it gives me error:
undefined reference to -> Phonon::VideoPlayer(Phonon::VideoCategory,QWidget*)
undefined reference to -> Phonon::VideoPlayer(Phonon::Mediasource const&)
Any idea?
Thanks..
Use either Phonon or QtMultimediaKit APIs.
For Phonon, there is a demo application in the Qt source tree (demos/qmediaplayer).
QtMultimediaKit is part of the QtMobility project, so in order to use it you require both Qt and QtMobility to be installed (in your SDK, and on the target device). There is a demo application in the QtMobility source tree (demos/mediaplayer).