Progress emit only when changed

asyncfuture.h

@@ -739,11 +739,6 @@ class DeferredFuture : public QObject, public QFutureInterface<T>{
  mutex.unlock();
  }
 
- void setParent(QFuture<void> future) {
- setParentProgressValue(future.progressValue());
- setParentProgressRange(future.progressMinimum(), future.progressMaximum());
- }
-
 protected:
  DeferredFuture(QObject* parent = nullptr): QObject(parent),
  QFutureInterface<T>(QFutureInterface<T>::Running),
@@ -790,11 +785,17 @@ class DeferredFuture : public QObject, public QFutureInterface<T>{
  }
 
  void updateProgressRanges() {
- QFutureInterface<T>::setProgressRange(0, parentProgress.range() + watchProgress.range());
+ int newMax = parentProgress.range() + watchProgress.range();
+ if(QFutureInterface<T>::progressMaximum() != newMax) {
+ QFutureInterface<T>::setProgressRange(0, newMax);
+ }
  }
 
  void updateProgressValue() {
- QFutureInterface<T>::setProgressValue(parentProgress.value + watchProgress.value);
+ int newProgress = parentProgress.value + watchProgress.value;
+ if(QFutureInterface<T>::progressValue() != newProgress) {
+ QFutureInterface<T>::setProgressValue(newProgress);
+ }
  }
 
  /// The future is already finished. It will take effect immediately
@@ -853,17 +854,21 @@ class CombinedFuture: public DeferredFuture<void> {
  progressFunc = [=](int progress) {
  mutex.lock();
  int diff = progress - *currentProgress;
- *currentProgress = progress;
- QFutureInterface<void>::setProgressValue(progressValue() + diff);
+ if(diff != 0) {
+ *currentProgress = progress;
+ QFutureInterface<void>::setProgressValue(progressValue() + diff);
+ }
  mutex.unlock();
  };
 
  progressRangeFunc = [=](int min, int max) {
  Q_UNUSED(min);
  mutex.lock();
  int diff = max - *progressIncrement;
- *progressIncrement = max;
- QFutureInterface<void>::setProgressRange(0, progressMaximum() + diff);
+ if(diff != 0) {
+ *progressIncrement = max;
+ QFutureInterface<void>::setProgressRange(0, progressMaximum() + diff);
+ }
  mutex.unlock();
  };
  }