How to run a shell script from qml ?

4w0nr4

I'm running Qt Creator 2.8.1 based on Qt 5.1.1 x64 and I'm trying to run a shell script ( just a basic test script ) from qml file. Somehow, this doesn't work for me and I'm not sure where the error is ?! Any help would be appreciated.

My files:

main.qml

@import QtQuick 2.0

Rectangle {
width: 360
height: 360

Text {
    text: "Hello World"
    anchors.centerIn: parent
}

MouseArea {
    anchors.fill: parent
    onClicked: ScriptLauncher.launchScript("bash")

}

}
@

main.cpp

@#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"
#include "scriptlauncher.h"
#include <QQmlContext>
#include <QQmlComponent>

int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);

QtQuick2ApplicationViewer viewer;
viewer.setMainQmlFile&#40;QStringLiteral("qml/scriptest2/main.qml"&#41;&#41;;
viewer.showExpanded(&#41;;

ScriptLauncher  launcher;

QQmlContext *context =viewer.rootContext();
context->setContextProperty("ScriptLauncher", &launcher);

//qmlRegisterType[removed]("myScriptLauncher", 1, 0, "ScriptLauncher");


return app.exec&#40;&#41;;

}
@

scriptlauncher.cpp

@#include "scriptlauncher.h"

ScriptLauncher::ScriptLauncher(QObject *parent) :
QObject(parent),
m_process(new QProcess(this))
{

}

void ScriptLauncher::launchScript()
{
m_process->start("./test.sh");

}
@

ScriptLauncher.h

@#ifndef SCRIPTLAUNCHER_H
#define SCRIPTLAUNCHER_H

#include <QObject>
#include <QProcess>

class ScriptLauncher : public QObject
{

Q_OBJECT

public:
explicit ScriptLauncher(QObject *parent = 0);
Q_INVOKABLE void launchScript();

private:
QProcess *m_process;
};

#endif // SCRIPTLAUNCHER_H
@

bobweaver

Hello there are you sure that you do not need to run your script in a emulator like gnome-terminal or something like that ?

I also notice in your qml file that you are calling the launcherscript() but you are giving it parameters

@
MouseArea {
anchors.fill: parent
onClicked: ScriptLauncher.launchScript("bash")
}@

But there is no parameters in your c++ code. You are just calling a script. Maybe try to make it
@

MouseArea {
anchors.fill: parent
onClicked: ScriptLauncher.launchScript()

}@

Unless you want to make it so you can pass application names and scripts to QProcess

example

@
void ScriptLauncher::launchScript(const QString &App)
{
m_process->start(App); // call a property that is passed from QML

}
@

and make that the same in you header file

@
Q_INVOKABLE void launchScript(const QString &App);
@

You could also make these properties available to QML with the Q_PROPERTY tag in you header files. Too Learn more about that check out the docs on C++ qml integration or Here is a full Qml Plugin if you would like to look at it.
https://github.com/bobweaver/qml-applauncher

Here is a example
@
import QtQuick 2.0
import ApplicationLauncher 1.0
Rectangle {
width: 360
height: 360

Text {
    text: "Hello World"
    anchors.centerIn: parent
}

MouseArea {
    anchors.fill: parent
    onClicked: {
        launcher.launchScript()
    }
}
Application{
    id: launcher

// or some path to a script run in a bash emulator like gnome-terminal or something like that.
appName: "vlc"
}

@

4w0nr4

Tnx for your suggestion. I've seen the mistake in this example. It is a leftover after many different test attemps. My MouseArea is actually empty. I have tried every posible combination and many other things., but still, somehow, it doesn't work ( ScriptLauncher.launchScript() ).

I want to run just a simple script to confirm that it works - and then i would implement something you have suggested in your example. But I can't get a confirmation.

I've build a tutorial project from /example/extend and it works, but it use QtQuick 1.0.

In any case, thanks your suggestion and help. It is appreciated.

bobweaver

Here is a Example of How you can do this. But I suggest reading more on qprocess and what you can do with it.

application.cpp
@
#include "application.h"
#include <QProcess>
#include <QDebug>
Application::Application(QObject *parent) :
QObject(parent),
m_process(new QProcess(this))
{
}
QString Application::appName() const
{
return m_AppName;
}
void Application::setAppName(const QString &appName)
{
m_AppName = appName;
}
void Application::launchScript()
{
// You can use start() if you want to start a external application
m_process->execute(m_AppName);
}
@

application.h

@
#ifndef APPLICATION_H
#define APPLICATION_H
#include <QObject>
#include <QProcess>
class Application : public QObject
{
Q_OBJECT

public:
explicit Application(QObject *parent = 0);

Q_PROPERTY( QString appName READ appName WRITE setAppName )

QString appName() const;
void setAppName(const QString &appName);

Q_INVOKABLE void launchScript();

private:
QProcess *m_process;
QString m_AppName;
};
#endif //APPLICATION_H
@

main.cpp
@
#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"
#include <qqml.h>
#include "application.h"
int main(int argc, char *argv[])
{

QGuiApplication app(argc, argv);
qmlRegisterType<Application>("Application", 1 , 0 , "App");
QtQuick2ApplicationViewer viewer;
viewer.setMainQmlFile&#40;QStringLiteral("qml/untitled9/main.qml"&#41;&#41;;
viewer.showExpanded();
return app.exec&#40;&#41;;

}
@

main.qml
@
import QtQuick 2.0
import Application 1.0
Rectangle {
width: 360
height: 360
Text {
text: qsTr("Hello World")
anchors.centerIn: parent
}
App{
id: bar
appName:"echo "Hello" This is a Simple test from C++"
}
MouseArea {
anchors.fill: parent
onClicked: {
bar.launchScript()
}
}
}
@

4w0nr4

Excelent !

This worked perfectly.... I will take your advice and I will look deeper into the qprocess docs. Thank you for your help and a great example....

AlbertoSalviaNovella

Example

Mind that the call is asynchronous. Hence the command sends a signal when it finishes, and a different part of the code picks the signal and continues with the next step you want to perform.