Why does running an Action inside update() crashes the application? - crash

Question

Good day,
The scenario is this, I have 3 sprites and I want to execute actions to them using sequence, inside the update().
Another thing if the sprite is still executing the action, it will not acquire new action but if it is done executing the action it will create a new action then execute it.
I used .isDone() for the checking.
Here is the pseudo code:
-Legend for readability:
SampleSprite - assuming that this is the array of sprites. isStillOnAction - boolean, true if currently executing action, false if not.
RANDOM NUMBER FROM 2-5 - is a random number from 2 to 5.
for(int ctr = 0; ctr < 3; ctr++){
if(!SpriteSample[ctr].isStillOnAction) // not currently executing action, so we can now assign an action
{
SampleSprite[ctr].isStillOnAction = true; // the isStillOnAction boolean is changed to true
if(SampleSprite[ctr].facingDirection == 1)
{
SampleSprite[ctr].moveAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 0, 100 ) );
SampleSprite[ctr].stoppingAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 10, 0 ) );
}
else if(SampleSprite[ctr].facingDirection == 2)
{
SampleSprite[ctr].moveAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 0, -100 ) );
SampleSprite[ctr].stoppingAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 10, 0 ) );
}
else if(SampleSprite[ctr].facingDirection == 3)
{
SampleSprite[ctr].moveAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( -100, 0 ) );
SampleSprite[ctr].stoppingAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 0,10 ) );
}
else if(SampleSprite[ctr].facingDirection == 4)
{
SampleSprite[ctr].moveAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 100, 0 ) );
SampleSprite[ctr].stoppingAction = cocos2d::MoveBy::create( RANDOM NUMBER FROM 2-5, cocos2d::Vec2( 0, 10 ) );
}
SampleSprite[ctr].moveStopAction = cocos2d::Sequence::create(SampleSprite[ctr].moveAction, SampleSprite[ctr].stoppingAction, nullptr);
SampleSprite[ctr].characterSprite->runAction( SampleSprite[ctr].moveStopAction );
}
else // currently executing action
{
if(SampleSprite[ctr].moveStopAction->isDone()) // check if done executing action
{
SampleSprite[ctr].isStillOnAction = false;
}
}}
Result:
It runs the sequence action but after that it freezes then it crashes.
What is the possible problem that I overlooked?
Thank you in advance smile

Answer 1

Running actions inside a scheduled function will not crash the app. The problem is likely to be:
the action has be released when you use .isDone(). When a action is done, it will decrease its reference count and be released unless you have retained it ( not recommended).
MoveBy::create() returns an auto-release object, which means if you don't call runAction on it or retain it, it will be released at the end of this frame.
You can use tags to check whether an action is running:
static const int MY_MOVEBY_ACTION = 3333;
for(int ctr = 0; ctr < 3; ctr++){
if(!SpriteSample[ctr].characterSprite->getActionByTag(MY_MOVE_ACTION)) // not currently executing action, so we can now assign an action
{
SampleSprite[ctr].isStillOnAction = true; // the isStillOnAction boolean is changed to true
//......
SampleSprite[ctr].moveStopAction = cocos2d::Sequence::create(SampleSprite[ctr].moveAction, SampleSprite[ctr].stoppingAction, nullptr);
moveStopAction->setTag(MY_MOVE_ACTION);
SampleSprite[ctr].characterSprite->runAction( SampleSprite[ctr].moveStopAction );
}
else // currently executing action
{
if(SampleSprite[ctr].moveStopAction->isDone()) // check if done executing action
{
SampleSprite[ctr].isStillOnAction = false;
}
}}