Problem with Tweens in (Sub)Stage - Tweens do not start

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Problem with Tweens in (Sub)Stage - Tweens do not start

(6 posts) (4 voices)

Started 10 months ago by christiansson
Latest reply from Shilo

Tags:

christiansson
Member

Hi,
i am new to sparrow, but it is just a great project! thanks for that ...

now, i am going to build my first (simple) game .. BUT i am running into a problem:

I have a SPStage subclass which is added as child to the main stage (Class: Game). Here is the Code:

@implementation PlayStage01
 
- (id)init {
    if ((self = [super init])) {
		SPTextField *title = [SPTextField textFieldWithWidth:320 height:70 text:@"Play ..... Stage 01" fontName:@"Helvetica" fontSize:70 color:0xFFFFFF];
        [self addChild:title];
 
		// Play Button
		SPTexture *buttonTexture = [SPTexture textureWithContentsOfFile:@"button_big.png"];
		SPButton *playButton = [SPButton buttonWithUpState:buttonTexture text:@"Play"];
		[playButton addEventListener:@selector(playButtonTriggered:) atObject:self
							 forType:SP_EVENT_TYPE_TRIGGERED];
		playButton.x = (320-playButton.width)/2;
		playButton.y = title.height + 20;
        [self addChild:playButton];
 
		[self startTween];
    }
 
    return self;
}
 
- (void)playButtonTriggered:(SPEvent *)event {
   /* Menu *menuScene = [[Menu alloc] init];
    [(Game *)self.stage showScene:menuScene];
	*/
	[self startTween];
 
}
 
-(void)startTween{
 
	SPImage *img = [SPImage imageWithContentsOfFile:@"texture_test.png"];
	[self addChild:img];
 
	SPTween *tween = [SPTween tweenWithTarget:img time:4.0];
	[tween animateProperty:@"y" targetValue:100.0f];
	[self.stage.juggler addObject:tween];
 
}

The Tween starts only after releasing the "playButtonTriggered" event calls "startTween"! The tween wont start, when the init function is calling start tween!

Why does this happen!? What am I doing wrong!?

Thank you for help in advance!
chris

Posted 10 months ago #

borrrden
Moderator

I remember reading that you should only use one SPStage object. So maybe the fact that you are using 2 is making it confused. Try making PlayStage inherit from SPSprite instead, and use your "Game" class's "showScene" function. If the juggler line gives you trouble after that try changing it to [[SPStage mainStage].juggler addObject...].

Posted 10 months ago #
Shilo
Master Sparrow

I agree with borrrden,

SPSprite will suit your needs. Once you change your class to subclass SPSprite instead of SPStage, it should work fine. Also as borrrden says, use "[SPStage mainStage]" to make sure it returns a valid object and not nil.

Posted 10 months ago #
christiansson
Member

Hi!

Thanks for your replies!

First: Changing the master class to SPSprite did not fix the problem! Same behavior BUT adding the tween like this to the main stage did the job:

[[SPStage mainStage].juggler addObject:tween];

Thank you guys!

chris

Posted 9 months ago #

Hen
Member

Hi,

I am having kind of the same problem as christiansson and using [SPStage mainStage] fixed part of my problem. I added an event listener to call when the tween finishes. For some reason it won't call.

 
#import "Trail.h"
#import "Square.h"
 
@implementation Trail
 
- (id)init:(Square *)sq
{
    self = [super initWithWidth:sq.width height:sq.height color:sq.color];
    if(self) {
        self.rotation = sq.rotation;
        self.x = sq.x;
        self.y = sq.y;
        SPTween *tween = [SPTween tweenWithTarget:self time:1.0f];
        [tween animateProperty:@"alpha" targetValue:0];
        [[SPStage mainStage].juggler addObject:tween];
        [tween addEventListener:@selector(destroySelf) atObject:self forType:SP_EVENT_TYPE_TWEEN_COMPLETED];
    }
    return self;
}
 
- (void)destroySelf
{
    NSLog(@"Trail was removed");
    [self.parent removeChild:self];
    [self release];
}
 
- (void)dealloc
{
    [super dealloc];
}
 
@end

Posted 9 months ago #

Shilo
Master Sparrow

That's because the callback method will take a SPEvent argument. You also need to add the ':' at the end of the @selector.

Like this:

#import "Trail.h"
#import "Square.h"
 
@implementation Trail
 
- (id)init:(Square *)sq
{
    self = [super initWithWidth:sq.width height:sq.height color:sq.color];
    if(self) {
        self.rotation = sq.rotation;
        self.x = sq.x;
        self.y = sq.y;
        SPTween *tween = [SPTween tweenWithTarget:self time:1.0f];
        [tween animateProperty:@"alpha" targetValue:0];
        [[SPStage mainStage].juggler addObject:tween];
        [tween addEventListener:@selector(destroySelf:) atObject:self forType:SP_EVENT_TYPE_TWEEN_COMPLETED];
    }
    return self;
}
 
- (void)destroySelf:(SPEvent *)event
{
    NSLog(@"Trail was removed");
    [self.parent removeChild:self];
    [self release];
}
 
- (void)dealloc
{
    [super dealloc];
}
 
@end

Posted 9 months ago #

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