@VinayBalajiRajputh said in Busy indicator in QML:
I have tried adding log messages and it seems only after the function open file is finished all the messages are logged
IMHO that's the expected behavior as you are not using thread and make everything in a function the events are blocked until execution is finished.
What you can do if to provide a property from TestClass whic indicates if thread is running, and then bind this property with the BusyIndicator.
But just a warning about the thread part, as I'm not an expert I reused your code with some modification for creating and starting the thread. But I don't think this is the correct way to use threads. I recommend that you read carefully QThread documentation, there is a nice example of how to use worker objects by moving them to the thread using QObject::moveToThread(). There are also other ways like QThreadPool and QRunnable or QtConcurrent.
There are also plenty of post on this forum and many others about how to use QThread
import QtQuick 2.10
import QtQuick.Window 2.10
//Post: https://forum.qt.io/topic/104906/busy-indicator-in-qml/3
import QtQuick 2.4
import QtQuick.Controls 1.3
import QtQuick.Window 2.2
import QtQuick.Dialogs 1.2
ApplicationWindow {
title: qsTr("Hello World")
width: 640
height: 480
visible: true
Connections{
target: obj
onIsRunningChanged: console.log("Running: " + obj.isRunning)
}
BusyIndicator {
id: indicator
running: obj.isRunning
anchors.centerIn: parent
}
Button {
text: "start"
anchors.top: parent.top
anchors.horizontalCenter: parent.horizontalCenter
onClicked: obj.runWorkerFuntion()
}
}
c++
//testclass.h
#ifndef TESTCLASS_H
#define TESTCLASS_H
#include <QObject>
class TestClass : public QObject
{
Q_OBJECT
Q_PROPERTY(bool isRunning READ isRunning NOTIFY isRunningChanged)
bool m_isRunning = false;
void workerFunction();
public:
explicit TestClass(QObject *parent = nullptr);
bool isRunning() const;
public slots:
void runWorkerFuntion();
signals:
void isRunningChanged(bool isRunning);
protected slots:
void setIsRunning(bool isRunning);
void threadStarted();
void threadFinished();
};
#endif // TESTCLASS_H
testclass.cpp
#include "testclass.h"
#include <QThread>
#include <QDebug>
TestClass::TestClass(QObject *parent) : QObject(parent)
{}
bool TestClass::isRunning() const
{
return m_isRunning;
}
void TestClass::runWorkerFuntion()
{
qDebug() << "runWorkerFuntion() from main thread: " << QThread::currentThreadId();
// /!\ THIS IS NOT A GOOD WAY TO USE THREAD
QThread* thread = QThread::create([this](){
workerFunction();
});
connect(thread, &QThread::started, this, &TestClass::threadStarted);
connect(thread, &QThread::finished, this, &TestClass::threadFinished);
connect(thread, &QThread::finished, thread, &QObject::deleteLater);
thread->start();
}
void TestClass::workerFunction()
{
qDebug() << "workerFunction() from thread: " << QThread::currentThreadId();
QThread::sleep(1);
}
void TestClass::setIsRunning(bool isRunning)
{
if (m_isRunning == isRunning)
return;
m_isRunning = isRunning;
emit isRunningChanged(m_isRunning);
}
void TestClass::threadStarted()
{
setIsRunning(true);
}
void TestClass::threadFinished()
{
setIsRunning(false);
}
console output:
runWorkerFuntion() from main thread: 0x4228
workerFunction() from thread: 0x15a4
qml: Running: true
qml: Running: false
