Swipe Gestures Demo for 3.6

cocos2d-x
1

Hello,

@Lem and @pabitrapadhy as well as many other users have struggled with swipe gestures on the new 3.6 version. Also i’ve added MoveBy actions to show also how to slide a sprite.

Inspired by the tutorial from @SonarSystems, i have created this basic swipe gesture demo:

692de94297ab8a04.gif959×657

Github:

Lets add more gestures to Cocos2D-X and this demo.
Half-circle swipe for example :wink:

2 Likes
2

Pretty cool, thanks for doing this :+1:

Instead of

    listener->onTouchCancelled = CC_CALLBACK_2(HelloWorld::onTouchCancelled, this);
.
.
.
void HelloWorld::onTouchCancelled(Touch *touch, Event *event)
        {
            onTouchEnded(touch, event);
        }

can’t we just do

    listener->onTouchCancelled = CC_CALLBACK_2(HelloWorld::onTouchEnded, this);

?

That seems simpler.

3

@i__d__k Good catch! Thank you. I’ll change that. Seems simpler indeed.

Can you help me with the update() function?

Line 60 the touch sprite:

auto icoTouch = Sprite::create("touchgfx/touch.png");  
icoTouch->setPosition(Point(currentTouchPos[0], currentTouchPos[1]));
this->addChild(icoTouch,1);   

FadeOut* fadeOut = FadeOut::create(0.5f);
icoTouch->runAction(fadeOut);

How do i delete the created sprite object from scene after it fades out?
This would be really helpful.

I’ve tried icoTouch->release(); and icoTouch->autorelease(); both crash the application.

1 Like
4

Just remove it form its parent,

icoTouch->removeFromParent();

But you will need to create an action sequence… You can see here for some guidance: http://www.cocos2d-x.org/wiki/Actions

5

@gkapur No, it doesn’t work in this context. Not sure about a sequence needed here:

03c3d3827dddf774.png1030×51

Again, it happens in the update function, so the logic should be create the sprite, fadeOut and when void HelloWorld::onTouchEnded(Touch *touch, Event *event) removeFromParent().

Otherwise the touch graphic will create too many verts overtime.
It needs to be removed after the trail is drawn at the same second by one.

I set a tag to the sprite, still not working:

void HelloWorld::onTouchEnded(Touch *touch, Event *event)
{
    isTouchDown = false;
    this->getChildByTag(25)->removeFromParentAndCleanup(true);
}

Any ideas? Its seems such a trivial thing.

6

It’s further down in that doc file.

  auto removeIt =  CallFunc::create([&icoTouch]() { icoTouch->removeFromParent() } ),

It should look something like that, I think. Might have to change the lambda expression capture but it should look something like that.

7

Looking good, check out our Cocos Helper project as it would be great if you wanted to integrate gestures into that.

8

@gkapur Trying further. This throws a EXC_BAD_ACCESS:

de06dd350028eb1a.png1063×131

Even if icoTouch is removed:

55d843f60dfad2be.png1039×111

Maybe there is another way to get them all?
Or really iterate through the node for all icoTouch sprites?

@SonarSystems Thank you! Sure, as soon as time allows it.
What do you think on how to remove the sprite in this case?

9

@gkapur Thank you very much again. Figured this out now:

auto removeIt = CallFunc::create([icoTouch]() {
            icoTouch->removeFromParent();
        });

It was the unnescessary &. Works perfectly now! Updating the repo… :smile:

EDIT: https://github.com/snlbase/Cocos2D-X/tree/master/Swipe%20Gestures

10

Great to see you have fixed it.