A thread that automatically pops up a modal dialog box with a progress bar and cancel button while it's busy running. More...

#include <juce_ThreadWithProgressWindow.h>

Inheritance diagram for ThreadWithProgressWindow:

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Collaboration diagram for ThreadWithProgressWindow:

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Public Types
enum	{ realtimeAudioPriority = -1 }
	Special realtime audio thread priority. More...

typedef void *	ThreadID
	A value type used for thread IDs. More...

Public Member Functions
	ThreadWithProgressWindow (const String &windowTitle, bool hasProgressBar, bool hasCancelButton, int timeOutMsWhenCancelling=10000, const String &cancelButtonText=String(), Component *componentToCentreAround=nullptr)
	Creates the thread. More...

	~ThreadWithProgressWindow ()
	Destructor. More...

AlertWindow *	getAlertWindow () const noexcept
	Returns the AlertWindow that is being used. More...

ThreadID	getThreadId () const noexcept
	Returns the ID of this thread. More...

const String &	getThreadName () const
	Returns the name of the thread. More...

bool	isThreadRunning () const
	Returns true if the thread is currently active. More...

void	launchThread (int priority=5)
	Starts the thread and returns. More...

void	notify () const
	Wakes up the thread. More...

virtual void	run ()=0
	Must be implemented to perform the thread's actual code. More...

bool	runThread (int priority=5)
	Starts the thread and waits for it to finish. More...

void	setAffinityMask (uint32 affinityMask)
	Sets the affinity mask for the thread. More...

bool	setPriority (int priority)
	Changes the thread's priority. More...

void	setProgress (double newProgress)
	The thread should call this periodically to update the position of the progress bar. More...

void	setStatusMessage (const String &newStatusMessage)
	The thread can call this to change the message that's displayed in the dialog box. More...

void	signalThreadShouldExit ()
	Sets a flag to tell the thread it should stop. More...

void	startThread ()
	Starts the thread running. More...

void	startThread (int priority)
	Starts the thread with a given priority. More...

bool	stopThread (int timeOutMilliseconds)
	Attempts to stop the thread running. More...

virtual void	threadComplete (bool userPressedCancel)
	This method is called (on the message thread) when the operation has finished. More...

bool	threadShouldExit () const
	Checks whether the thread has been told to stop running. More...

bool	wait (int timeOutMilliseconds) const
	Makes the thread wait for a notification. More...

bool	waitForThreadToExit (int timeOutMilliseconds) const
	Waits for the thread to stop. More...

Static Public Member Functions
static bool	currentThreadShouldExit ()
	Checks whether the current thread has been told to stop running. More...

static Thread *	getCurrentThread ()
	Finds the thread object that is currently running. More...

static ThreadID	getCurrentThreadId ()
	Returns an id that identifies the caller thread. More...

static void	setCurrentThreadAffinityMask (uint32 affinityMask)
	Changes the affinity mask for the caller thread. More...

static void	setCurrentThreadName (const String &newThreadName)
	Changes the name of the caller thread. More...

static bool	setCurrentThreadPriority (int priority)
	Changes the priority of the caller thread. More...

static void	sleep (int milliseconds)

static void	yield ()
	Yields the calling thread's current time-slot. More...

Private Member Functions
int	getTimerInterval () const noexcept
	Returns the timer's interval. More...

bool	isTimerRunning () const noexcept
	Returns true if the timer is currently running. More...

void	startTimer (int intervalInMilliseconds) noexcept
	Starts the timer and sets the length of interval required. More...

void	startTimerHz (int timerFrequencyHz) noexcept
	Starts the timer with an interval specified in Hertz. More...

void	stopTimer () noexcept
	Stops the timer. More...

void	timerCallback () override
	The user-defined callback routine that actually gets called periodically. More...

Static Private Member Functions
static void	callAfterDelay (int milliseconds, std::function< void()> functionToCall)
	Invokes a lambda after a given number of milliseconds. More...

static void	callPendingTimersSynchronously ()
	For internal use only: invokes any timers that need callbacks. More...

Private Attributes
ScopedPointer< AlertWindow >	alertWindow

String	message

CriticalSection	messageLock

double	progress

const int	timeOutMsWhenCancelling

bool	wasCancelledByUser

Detailed Description

A thread that automatically pops up a modal dialog box with a progress bar and cancel button while it's busy running.

These are handy for performing some sort of task while giving the user feedback about how long there is to go, etc.

E.g.

class MyTask  : public ThreadWithProgressWindow
{
public:
    MyTask()    : ThreadWithProgressWindow ("busy...", true, true)
    {
    }
    void run()
    {
        for (int i = 0; i < thingsToDo; ++i)
        {
            // must check this as often as possible, because this is
            // how we know if the user's pressed 'cancel'
            if (threadShouldExit())
                break;
            // this will update the progress bar on the dialog box
            setProgress (i / (double) thingsToDo);
            //   ... do the business here...
        }
    }
};
void doTheTask()
{
    MyTask m;
    if (m.runThread())
    {
        // thread finished normally..
    }
    else
    {
        // user pressed the cancel button..
    }
}

See also: Thread, AlertWindow

Member Typedef Documentation

◆ ThreadID

typedef void* Thread::ThreadID

inherited

A value type used for thread IDs.

See also: getCurrentThreadId(), getThreadId()

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

inherited

Special realtime audio thread priority.

This priority will create a high-priority thread which is best suited for realtime audio processing.

Currently, this priority is identical to priority 9, except when building for Android with OpenSL support.

In this case, JUCE will ask OpenSL to consturct a super high priority thread specifically for realtime audio processing.

Note that this priority can only be set before the thread has started. Switching to this priority, or from this priority to a different priority, is not supported under Android and will assert.

For best performance this thread should yield at regular intervals and not call any blocking APIS.

See also: startThread, setPriority, sleep, WaitableEvent

Enumerator
realtimeAudioPriority

Constructor & Destructor Documentation

◆ ThreadWithProgressWindow()

ThreadWithProgressWindow::ThreadWithProgressWindow	(	const String &	windowTitle,
		bool	hasProgressBar,
		bool	hasCancelButton,
		int	timeOutMsWhenCancelling = `10000`,
		const String &	cancelButtonText = `String()`,
		Component *	componentToCentreAround = `nullptr`
	)

Creates the thread.

Initially, the dialog box won't be visible, it'll only appear when the runThread() method is called.

Parameters

windowTitle	the title to go at the top of the dialog box
hasProgressBar	whether the dialog box should have a progress bar (see setProgress() )
hasCancelButton	whether the dialog box should have a cancel button
timeOutMsWhenCancelling	when 'cancel' is pressed, this is how long to wait for the thread to stop before killing it forcibly (see Thread::stopThread() )
cancelButtonText	the text that should be shown in the cancel button (if it has one). Leave this empty for the default "Cancel"
componentToCentreAround	if this is non-null, the window will be positioned so that it's centred around this component.

◆ ~ThreadWithProgressWindow()

ThreadWithProgressWindow::~ThreadWithProgressWindow ( )

Destructor.

Member Function Documentation

◆ callAfterDelay()

static void Timer::callAfterDelay	(	int	milliseconds,
		std::function< void()>	functionToCall
	)

staticinherited

Invokes a lambda after a given number of milliseconds.

◆ callPendingTimersSynchronously()

static void Timer::callPendingTimersSynchronously ( )

staticinherited

For internal use only: invokes any timers that need callbacks.

Don't call this unless you really know what you're doing!

◆ currentThreadShouldExit()

static bool Thread::currentThreadShouldExit ( )

staticinherited

Checks whether the current thread has been told to stop running.

On the message thread, this will always return false, otherwise it will return threadShouldExit() called on the current thread.

See also: threadShouldExit

◆ getAlertWindow()

AlertWindow* ThreadWithProgressWindow::getAlertWindow ( ) const

inlinenoexcept

Returns the AlertWindow that is being used.

References Timer::timerCallback().

◆ getCurrentThread()

static Thread* Thread::getCurrentThread ( )

staticinherited

Finds the thread object that is currently running.

Note that the main UI thread (or other non-Juce threads) don't have a Thread object associated with them, so this will return nullptr.

◆ getCurrentThreadId()

Thread::ThreadID Thread::getCurrentThreadId ( )

staticinherited

Returns an id that identifies the caller thread.

To find the ID of a particular thread object, use getThreadId().

Returns: a unique identifier that identifies the calling thread.

See also: getThreadId

Referenced by ThreadLocalValue< Type >::get(), and ThreadLocalValue< Type >::releaseCurrentThreadStorage().

◆ getThreadId()

ThreadID Thread::getThreadId ( ) const

inlinenoexceptinherited

Returns the ID of this thread.

That means the ID of this thread object - not of the thread that's calling the method.

This can change when the thread is started and stopped, and will be invalid if the thread's not actually running.

See also: getCurrentThreadId

◆ getThreadName()

const String& Thread::getThreadName ( ) const

inlineinherited

Returns the name of the thread.

This is the name that gets set in the constructor.

References JUCE_CALLTYPE.

◆ getTimerInterval()

int Timer::getTimerInterval ( ) const

inlinenoexceptinherited

Returns the timer's interval.

Returns: the timer's interval in milliseconds if it's running, or 0 if it's not.

References JUCE_CALLTYPE.

Referenced by CarbonViewWrapperComponent::setOurSizeToEmbeddedViewSize().

◆ isThreadRunning()

bool Thread::isThreadRunning ( ) const

inherited

Returns true if the thread is currently active.

◆ isTimerRunning()

bool Timer::isTimerRunning ( ) const

inlinenoexceptinherited

Returns true if the timer is currently running.

◆ launchThread()

void ThreadWithProgressWindow::launchThread ( int priority = 5 )

Starts the thread and returns.

This will start the thread and make the dialog box appear in a modal state. When the thread finishes normally, or the cancel button is pressed, the window will be hidden and the threadComplete() method will be called.

Parameters

priority the priority to use when starting the thread - see Thread::startThread() for values

◆ notify()

void Thread::notify ( ) const

inherited

Wakes up the thread.

If the thread has called the wait() method, this will wake it up.

See also: wait

◆ run()

virtual void Thread::run ( )

pure virtualinherited

Must be implemented to perform the thread's actual code.

Remember that the thread must regularly check the threadShouldExit() method whilst running, and if this returns true it should return from the run() method as soon as possible to avoid being forcibly killed.

See also: threadShouldExit, startThread

Implemented in MidiOutput, and InterprocessConnectionServer.

◆ runThread()

bool ThreadWithProgressWindow::runThread ( int priority = 5 )

Starts the thread and waits for it to finish.

This will start the thread, make the dialog box appear, and wait until either the thread finishes normally, or until the cancel button is pressed.

Before returning, the dialog box will be hidden.

Parameters

priority the priority to use when starting the thread - see Thread::startThread() for values

Returns: true if the thread finished normally; false if the user pressed cancel

◆ setAffinityMask()

void Thread::setAffinityMask ( uint32 affinityMask )

inherited

Sets the affinity mask for the thread.

This will only have an effect next time the thread is started - i.e. if the thread is already running when called, it'll have no effect.

See also: setCurrentThreadAffinityMask

◆ setCurrentThreadAffinityMask()

void Thread::setCurrentThreadAffinityMask ( uint32 affinityMask )

staticinherited

Changes the affinity mask for the caller thread.

This will change the affinity mask for the thread that calls this static method.

See also: setAffinityMask

References juce::ignoreUnused(), and jassertfalse.

◆ setCurrentThreadName()

void Thread::setCurrentThreadName ( const String & newThreadName )

staticinherited

Changes the name of the caller thread.

Different OSes may place different length or content limits on this name.

References JUCE_AUTORELEASEPOOL, anonymous_namespace{juce_osx_ObjCHelpers.h}::juceStringToNS(), setName, and String::toRawUTF8().

◆ setCurrentThreadPriority()

static bool Thread::setCurrentThreadPriority ( int priority )

staticinherited

Changes the priority of the caller thread.

Similar to setPriority(), but this static method acts on the caller thread. May return false if for some reason the priority can't be changed.

See also: setPriority

◆ setPriority()

bool Thread::setPriority ( int priority )

inherited

Changes the thread's priority.

May return false if for some reason the priority can't be changed.

Parameters

priority the new priority, in the range 0 (lowest) to 10 (highest). A priority of 5 is normal.

See also: realtimeAudioPriority

◆ setProgress()

void ThreadWithProgressWindow::setProgress ( double newProgress )

The thread should call this periodically to update the position of the progress bar.

Parameters

newProgress the progress, from 0.0 to 1.0

See also: setStatusMessage

◆ setStatusMessage()

void ThreadWithProgressWindow::setStatusMessage ( const String & newStatusMessage )

The thread can call this to change the message that's displayed in the dialog box.

◆ signalThreadShouldExit()

void Thread::signalThreadShouldExit ( )

inherited

Sets a flag to tell the thread it should stop.

Calling this means that the threadShouldExit() method will then return true. The thread should be regularly checking this to see whether it should exit.

If your thread makes use of wait(), you might want to call notify() after calling this method, to interrupt any waits that might be in progress, and allow it to reach a point where it can exit.

See also: threadShouldExit; waitForThreadToExit

◆ sleep()

void Thread::sleep ( int milliseconds )

staticinherited

Referenced by OpenGLContext::NativeContext::swapBuffers().

◆ startThread() [1/2]

void Thread::startThread ( )

inherited

Starts the thread running.

This will cause the thread's run() method to be called by a new thread. If this thread is already running, startThread() won't do anything.

See also: stopThread

◆ startThread() [2/2]

void Thread::startThread ( int priority )

inherited

Starts the thread with a given priority.

Launches the thread with a given priority, where 0 = lowest, 10 = highest. If the thread is already running, its priority will be changed.

See also: startThread, setPriority, realtimeAudioPriority

◆ startTimer()

void Timer::startTimer ( int intervalInMilliseconds )

noexceptinherited

Starts the timer and sets the length of interval required.

If the timer is already started, this will reset it, so the time between calling this method and the next timer callback will not be less than the interval length passed in.

Parameters

intervalInMilliseconds the interval to use (any value less than 1 will be rounded up to 1)

Referenced by FakeMouseMoveGenerator::FakeMouseMoveGenerator(), StandalonePluginHolder::init(), and CarbonViewWrapperComponent::setOurSizeToEmbeddedViewSize().

◆ startTimerHz()

void Timer::startTimerHz ( int timerFrequencyHz )

noexceptinherited

Starts the timer with an interval specified in Hertz.

This is effectively the same as calling startTimer (1000 / timerFrequencyHz).

Referenced by AnimatedPosition< Behaviour >::endDrag(), AnimatedPosition< Behaviour >::nudge(), and AnimatedPosition< Behaviour >::timerCallback().

◆ stopThread()

bool Thread::stopThread ( int timeOutMilliseconds )

inherited

Attempts to stop the thread running.

This method will cause the threadShouldExit() method to return true and call notify() in case the thread is currently waiting.

Hopefully the thread will then respond to this by exiting cleanly, and the stopThread method will wait for a given time-period for this to happen.

If the thread is stuck and fails to respond after the time-out, it gets forcibly killed, which is a very bad thing to happen, as it could still be holding locks, etc. which are needed by other parts of your program.

Parameters

timeOutMilliseconds The number of milliseconds to wait for the thread to finish before killing it by force. A negative value in here will wait forever.

Returns: true if the thread was cleanly stopped before the timeout, or false if it had to be killed by force.

See also: signalThreadShouldExit, threadShouldExit, waitForThreadToExit, isThreadRunning

◆ stopTimer()

void Timer::stopTimer ( )

noexceptinherited

Stops the timer.

No more timer callbacks will be triggered after this method returns.

Note that if you call this from a background thread while the message-thread is already in the middle of your callback, then this method will cancel any future timer callbacks, but it will return without waiting for the current one to finish. The current callback will continue, possibly still running some of your timer code after this method has returned.

Referenced by AnimatedPosition< Behaviour >::beginDrag(), CarbonViewWrapperComponent::setOurSizeToEmbeddedViewSize(), AnimatedPosition< Behaviour >::setPosition(), AnimatedPosition< Behaviour >::timerCallback(), and StandalonePluginHolder::~StandalonePluginHolder().

◆ threadComplete()

virtual void ThreadWithProgressWindow::threadComplete ( bool userPressedCancel )

virtual

This method is called (on the message thread) when the operation has finished.

You may choose to use this callback to delete the ThreadWithProgressWindow object.

◆ threadShouldExit()

bool Thread::threadShouldExit ( ) const

inlineinherited

Checks whether the thread has been told to stop running.

Threads need to check this regularly, and if it returns true, they should return from their run() method at the first possible opportunity.

See also: signalThreadShouldExit, currentThreadShouldExit

◆ timerCallback()

void ThreadWithProgressWindow::timerCallback ( )

overrideprivatevirtual

The user-defined callback routine that actually gets called periodically.

It's perfectly ok to call startTimer() or stopTimer() from within this callback to change the subsequent intervals.

Implements Timer.

◆ wait()

bool Thread::wait ( int timeOutMilliseconds ) const

inherited

Makes the thread wait for a notification.

This puts the thread to sleep until either the timeout period expires, or another thread calls the notify() method to wake it up.

A negative time-out value means that the method will wait indefinitely.

Returns: true if the event has been signalled, false if the timeout expires.

◆ waitForThreadToExit()

bool Thread::waitForThreadToExit ( int timeOutMilliseconds ) const

inherited

Waits for the thread to stop.

This will waits until isThreadRunning() is false or until a timeout expires.

Parameters

timeOutMilliseconds the time to wait, in milliseconds. If this value is less than zero, it will wait forever.

Returns: true if the thread exits, or false if the timeout expires first.

◆ yield()

void Thread::yield ( )

staticinherited

Yields the calling thread's current time-slot.

Member Data Documentation

◆ alertWindow

ScopedPointer<AlertWindow> ThreadWithProgressWindow::alertWindow

private

◆ message

String ThreadWithProgressWindow::message

private

◆ messageLock

CriticalSection ThreadWithProgressWindow::messageLock

private

◆ progress

double ThreadWithProgressWindow::progress

private

◆ timeOutMsWhenCancelling

const int ThreadWithProgressWindow::timeOutMsWhenCancelling

private

◆ wasCancelledByUser

bool ThreadWithProgressWindow::wasCancelledByUser

private

The documentation for this class was generated from the following file:

juce_ThreadWithProgressWindow.h

Public Types

Public Member Functions

Static Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ ThreadID

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ ThreadWithProgressWindow()

◆ ~ThreadWithProgressWindow()

Member Function Documentation

◆ callAfterDelay()

◆ callPendingTimersSynchronously()

◆ currentThreadShouldExit()

◆ getAlertWindow()

◆ getCurrentThread()

◆ getCurrentThreadId()

◆ getThreadId()

◆ getThreadName()

◆ getTimerInterval()

◆ isThreadRunning()

◆ isTimerRunning()

◆ launchThread()

◆ notify()

◆ run()

◆ runThread()

◆ setAffinityMask()

◆ setCurrentThreadAffinityMask()

◆ setCurrentThreadName()

◆ setCurrentThreadPriority()

◆ setPriority()

◆ setProgress()

◆ setStatusMessage()

◆ signalThreadShouldExit()

◆ sleep()

◆ startThread() [1/2]

◆ startThread() [2/2]

◆ startTimer()

◆ startTimerHz()

◆ stopThread()

◆ stopTimer()

◆ threadComplete()

◆ threadShouldExit()

◆ timerCallback()

◆ wait()

◆ waitForThreadToExit()

◆ yield()

Member Data Documentation

◆ alertWindow

◆ message

◆ messageLock

◆ progress

◆ timeOutMsWhenCancelling

◆ wasCancelledByUser