fix the issue the sequence action will not be invoked (#17906)

* fix the issue the sequence action will not be invoked

* add comment

* update _done in update() function

cocos/2d/CCActionInstant.cpp

@@ -62,12 +62,11 @@ void ActionInstant::step(float /*dt*/)
     }
 #endif
     update(updateDt);
-    _done = true;
 }
 
 void ActionInstant::update(float /*time*/)
 {
-    // nothing
+    _done = true;
 }
 
 //
@@ -86,8 +85,9 @@ Show* Show::create()
     return ret;
 }
 
-void Show::update(float /*time*/)
+void Show::update(float time)
 {
+    ActionInstant::update(time);
     _target->setVisible(true);
 }
 
@@ -117,8 +117,9 @@ Hide * Hide::create()
     return ret;
 }
 
-void Hide::update(float /*time*/)
+void Hide::update(float time)
 {
+    ActionInstant::update(time);
     _target->setVisible(false);
 }
 
@@ -148,8 +149,9 @@ ToggleVisibility * ToggleVisibility::create()
     return ret;
 }
 
-void ToggleVisibility::update(float /*time*/)
+void ToggleVisibility::update(float time)
 {
+    ActionInstant::update(time);
     _target->setVisible(!_target->isVisible());
 }
 
@@ -185,8 +187,9 @@ bool RemoveSelf::init(bool isNeedCleanUp)
     return true;
 }
 
-void RemoveSelf::update(float /*time*/)
+void RemoveSelf::update(float time)
 {
+    ActionInstant::update(time);
     _target->removeFromParentAndCleanup(_isNeedCleanUp);
 }
 
@@ -225,8 +228,9 @@ bool FlipX::initWithFlipX(bool x)
     return true;
 }
 
-void FlipX::update(float /*time*/)
+void FlipX::update(float time)
 {
+    ActionInstant::update(time);
     static_cast<Sprite*>(_target)->setFlippedX(_flipX);
 }
 
@@ -264,8 +268,9 @@ bool FlipY::initWithFlipY(bool y)
     return true;
 }
 
-void FlipY::update(float /*time*/)
+void FlipY::update(float time)
 {
+    ActionInstant::update(time);
     static_cast<Sprite*>(_target)->setFlippedY(_flipY);
 }
 
@@ -316,8 +321,9 @@ Place * Place::reverse() const
     return this->clone();
 }
 
-void Place::update(float /*time*/)
+void Place::update(float time)
 {
+    ActionInstant::update(time);
     _target->setPosition(_position);
 }
 
@@ -405,8 +411,9 @@ CallFunc * CallFunc::reverse() const
     return this->clone();
 }
 
-void CallFunc::update(float /*time*/)
+void CallFunc::update(float time)
 {
+    ActionInstant::update(time);
     this->execute();
 }
 

cocos/2d/CCActionInterval.cpp

@@ -285,6 +285,12 @@ bool Sequence::initWithTwoActions(FiniteTimeAction *actionOne, FiniteTimeAction
     return true;
 }
 
+bool Sequence::isDone() const
+{
+    // fix issue #17884
+    return (ActionInterval::isDone() && _actions[1]->isDone());
+}
+
 Sequence* Sequence::clone() const
 {
     // no copy constructor

cocos/2d/CCActionInterval.h

@@ -185,6 +185,7 @@ public:
     virtual Sequence* reverse() const override;
     virtual void startWithTarget(Node *target) override;
     virtual void stop(void) override;
+    virtual bool isDone() const override;
     /**
      * @param t In seconds.
      */