Used internally by the Value class as the base class for its shared value objects. More...
#include <juce_Value.h>
Public Member Functions | |
ValueSource () | |
~ValueSource () override | |
void | decReferenceCount () noexcept |
Decreases the object's reference count. More... | |
bool | decReferenceCountWithoutDeleting () noexcept |
Decreases the object's reference count. More... | |
int | getReferenceCount () const noexcept |
Returns the object's current reference count. More... | |
virtual var | getValue () const =0 |
Returns the current value of this object. More... | |
void | incReferenceCount () noexcept |
Increments the object's reference count. More... | |
void | sendChangeMessage (bool dispatchSynchronously) |
Delivers a change message to all the listeners that are registered with this value. More... | |
virtual void | setValue (const var &newValue)=0 |
Changes the current value. More... | |
Protected Member Functions | |
void | resetReferenceCount () noexcept |
Resets the reference count to zero without deleting the object. More... | |
Protected Attributes | |
SortedSet< Value * > | valuesWithListeners |
Private Member Functions | |
void | cancelPendingUpdate () noexcept |
This will stop any pending updates from happening. More... | |
void | handleAsyncUpdate () override |
Called back to do whatever your class needs to do. More... | |
void | handleUpdateNowIfNeeded () |
If an update has been triggered and is pending, this will invoke it synchronously. More... | |
bool | isUpdatePending () const noexcept |
Returns true if there's an update callback in the pipeline. More... | |
void | triggerAsyncUpdate () |
Causes the callback to be triggered at a later time. More... | |
Private Attributes | |
ReferenceCountedObjectPtr< AsyncUpdaterMessage > | activeMessage |
Atomic< int > | refCount { 0 } |
Friends | |
class | Value |
Used internally by the Value class as the base class for its shared value objects.
The Value class is essentially a reference-counted pointer to a shared instance of a ValueSource object. If you're feeling adventurous, you can create your own custom ValueSource classes to allow Value objects to represent your own custom data items.
juce::Value::ValueSource::ValueSource | ( | ) |
|
override |
|
noexceptinherited |
This will stop any pending updates from happening.
If called after triggerAsyncUpdate() and before the handleAsyncUpdate() callback happens, this will cancel the handleAsyncUpdate() callback.
Note that this method simply cancels the next callback - if a callback is already in progress on a different thread, this won't block until the callback finishes, so there's no guarantee that the callback isn't still running when the method returns.
|
inlinenoexceptinherited |
Decreases the object's reference count.
If the count gets to zero, the object will be deleted.
References jassert.
|
inlinenoexceptinherited |
Decreases the object's reference count.
If the count gets to zero, the object will not be deleted, but this method will return true, allowing the caller to take care of deletion.
References jassert.
|
inlinenoexceptinherited |
Returns the object's current reference count.
|
pure virtual |
Returns the current value of this object.
Implemented in juce::ValueTreePropertyWithDefault::SynchronousValueSource.
|
overrideprivatevirtual |
Called back to do whatever your class needs to do.
This method is called by the message thread at the next convenient time after the triggerAsyncUpdate() method has been called.
Implements juce::AsyncUpdater.
|
inherited |
If an update has been triggered and is pending, this will invoke it synchronously.
Use this as a kind of "flush" operation - if an update is pending, the handleAsyncUpdate() method will be called immediately; if no update is pending, then nothing will be done.
Because this may invoke the callback, this method must only be called on the main event thread.
|
inlinenoexceptinherited |
Increments the object's reference count.
This is done automatically by the smart pointer, but is public just in case it's needed for nefarious purposes.
Referenced by juce::ReferenceCountedObjectPtr< juce::ReferenceCountedObject >::operator=().
|
noexceptinherited |
Returns true if there's an update callback in the pipeline.
|
inlineprotectednoexceptinherited |
Resets the reference count to zero without deleting the object.
You should probably never need to use this!
void juce::Value::ValueSource::sendChangeMessage | ( | bool | dispatchSynchronously | ) |
Delivers a change message to all the listeners that are registered with this value.
If dispatchSynchronously is true, the method will call all the listeners before returning; otherwise it'll dispatch a message and make the call later.
|
pure virtual |
Changes the current value.
This must also trigger a change message if the value actually changes.
Implemented in juce::ValueTreePropertyWithDefault::SynchronousValueSource.
|
inherited |
Causes the callback to be triggered at a later time.
This method returns immediately, after which a callback to the handleAsyncUpdate() method will be made by the message thread as soon as possible.
If an update callback is already pending but hasn't happened yet, calling this method will have no effect.
It's thread-safe to call this method from any thread, BUT beware of calling it from a real-time (e.g. audio) thread, because it involves posting a message to the system queue, which means it may block (and in general will do on most OSes).
|
friend |
|
privateinherited |