Ich habe einen View Controller, der als Kinder drei Szenen hat.

Beim Übergang von einer zur anderen wird die alte Szene nicht freigegeben.

Ich möchte, dass es freigegeben wird, als wäre es nie da.

Beispiel:

Wenn ich die App zum ersten Mal lade, ist nur 1 Szene sichtbar (dh sie belegt 100 MB Speicher), dann wechsle ich zu einer anderen (100 MB mehr) und dann zur dritten (300 MB Speicher).

Ich würde mit 300 MB Speicher enden und ich möchte jederzeit 100 haben.

Wie kann ich das erreichen?

My view controller: 

//
//  ViewController.m
//  Paddle Jumper
//
//  Created by Chance Daniel on 1/18/14.
//  Copyright (c) 2014 Max Hudson. All rights reserved.
//

#import "Flurry.h"
#import "ViewController.h"
#import "startViewController.h"

@implementation ViewController{
    BOOL sceneSetUp;
}

- (void)viewWillLayoutSubviews
{
    if(!sceneSetUp){

        [super viewWillLayoutSubviews];

        // Configure the view.
        SKView * skView = (SKView *)self.view;
        //skView.showsFPS = YES;
        //skView.showsNodeCount = YES;

        NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
        if([[defaults objectForKey:@"firstTime"] intValue] != 1){
            [defaults setObject:[NSNumber numberWithInt:1] forKey:@"firstTime"];

            [defaults setObject:@"ggr" forKey:@"skinSelected"];
            [defaults setObject:[NSNumber numberWithInt:2] forKey:@"ggrOwned"];

            [defaults setObject:[NSNumber numberWithInt:5000] forKey:@"gona"];
            [defaults setObject:[NSNumber numberWithInt:1500] forKey:@"points"];
            [defaults setObject:[NSNumber numberWithInt:7] forKey:@"livesLeftValue"];
            [defaults setObject:[NSNumber numberWithInt:3] forKey:@"shieldsLeftValue"];
            [defaults setObject:[NSNumber numberWithInt:2] forKey:@"lvlTwoLeftValue"];
            [defaults setObject:[NSNumber numberWithInt:0] forKey:@"lvlThreeLeftValue"];
        }

        if(![defaults objectForKey:@"tut_game1"]){
            [defaults setObject:[NSNumber numberWithInt:1] forKey:@"tut_game1"];
            [defaults setObject:[NSNumber numberWithInt:1] forKey:@"tut_store"];
            [defaults setObject:[NSNumber numberWithInt:1] forKey:@"tut_daily"];
        }

        [defaults synchronize];

        // Create and configure the scene.
        SKScene * startScene = [StartViewController sceneWithSize:skView.bounds.size];
        startScene.scaleMode = SKSceneScaleModeAspectFill;

        // Present the scene.
        [skView presentScene:startScene];
        //[skView presentScene:scene];

        sceneSetUp = YES;
    }

}

-(void) switchScene{

}

- (BOOL)shouldAutorotate
{
    return YES;
}

- (NSUInteger)supportedInterfaceOrientations
{
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
        return UIInterfaceOrientationMaskAllButUpsideDown;
    } else {
        return UIInterfaceOrientationMaskAll;
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Release any cached data, images, etc that aren't in use.
}

@end

An SKScene that won't release: //
//  SettingsSKScene.m
//  Paddle Jumper
//
//  Created by Max Hudson on 3/15/14.
//  Copyright (c) 2014 Max Hudson. All rights reserved.
//

#import "SettingsSKScene.h"
#import "gameViewController.h"
#import "StoreScene.h"

@interface SettingsSKScene (){
    SKSpriteNode *bg;
    SKSpriteNode *masterOverlay;
    SKSpriteNode *wbox;
    SKSpriteNode *gamecenter;
    SKSpriteNode *max;
    SKSpriteNode *chance;
    SKSpriteNode *bryce;
    SKSpriteNode *home;
    SKSpriteNode *play;

    SKSpriteNode *chance_link;
    SKSpriteNode *max_link;
    SKSpriteNode *bryce_link;

    SKSpriteNode *fbButton;
    SKSpriteNode *fbToggleYes;
    SKSpriteNode *fbToggleNo;

    SKLabelNode *story1;
    SKLabelNode *story2;
    SKLabelNode *story3;

    SKLabelNode *chance_name;
    SKLabelNode *max_name;
    SKLabelNode *bryce_name;

    SKLabelNode *chance_role;
    SKLabelNode *max_role;
    SKLabelNode *bryce_role;

    SKLabelNode *chance_handle;
    SKLabelNode *max_handle;
    SKLabelNode *bryce_handle;

    SKTexture *bg_texture;
    SKTexture *gamecenter_texture;
    SKTexture *wbox_texture;
    SKTexture *max_texture;
    SKTexture *chance_texture;
    SKTexture *bryce_texture;
    SKTexture *home_texture;
    SKTexture *play_texture;
    SKTexture *fb_texture;
    SKTexture *toggle_yes_texture;
    SKTexture *toggle_no_texture;
}

@end

@implementation SettingsSKScene

-(id) initWithSize:(CGSize)size{
    if(self = [super initWithSize:size]){
        masterOverlay = [SKSpriteNode spriteNodeWithColor:[SKColor blackColor] size:self.frame.size];
        masterOverlay.position = CGPointMake(self.frame.size.width/2, self.frame.size.height/2);
        [self addChild:masterOverlay];

        bg_texture = [SKTexture textureWithImageNamed:@"settings_bg"];
        wbox_texture = [SKTexture textureWithImageNamed:@"white_rect_bg"];
        gamecenter_texture = [SKTexture textureWithImageNamed:@"gc"];
        max_texture = [SKTexture textureWithImageNamed:@"max"];
        chance_texture = [SKTexture textureWithImageNamed:@"chance"];
        bryce_texture = [SKTexture textureWithImageNamed:@"bryce"];
        home_texture = [SKTexture textureWithImageNamed:@"home_light"];
        play_texture = [SKTexture textureWithImageNamed:@"play_light"];
        fb_texture = [SKTexture textureWithImageNamed:@"fb_light"];
        toggle_yes_texture = [SKTexture textureWithImageNamed:@"toggle_yes"];
        toggle_no_texture = [SKTexture textureWithImageNamed:@"toggle_no"];

        NSArray *to_preload = @[bg_texture, wbox_texture, gamecenter_texture, max_texture, chance_texture, bryce_texture, home_texture, play_texture, fb_texture, toggle_yes_texture, toggle_no_texture];

        [SKTexture preloadTextures:to_preload withCompletionHandler:^{
            [self fadeRemove:masterOverlay];
            [self initialize];
        }];
    }
    return self;
}

-(void) fadeRemove: (SKNode *) node{
    double duration = arc4random() % 10;
    duration *= 0.05;
    SKAction *fadeOut = [SKAction fadeOutWithDuration:0.1+duration];
    SKAction *remove = [SKAction runBlock:^{
        [node removeFromParent];
    }];

    [node runAction:[SKAction sequence:@[fadeOut, remove]]];
}

-(void) initialize{
    bg = [SKSpriteNode spriteNodeWithTexture:bg_texture];
    bg.position = CGPointMake(self.frame.size.width/2, self.frame.size.height/2);
    bg.zPosition = 0;

    wbox = [SKSpriteNode spriteNodeWithTexture:wbox_texture];
    wbox.position = CGPointMake(self.frame.size.width/2, 70);
    wbox.alpha = 0.8;
    wbox.zPosition = 2;

    gamecenter = [SKSpriteNode spriteNodeWithTexture:gamecenter_texture];
    gamecenter.position = CGPointMake(self.frame.size.width/2 + 100, self.frame.size.height/2-2);
    gamecenter.name = @"gc";
    gamecenter.zPosition = 2;

    fbButton = [SKSpriteNode spriteNodeWithTexture:fb_texture];
    fbButton.size = CGSizeMake(36, 36);
    fbButton.position = CGPointMake(self.frame.size.width/2 - 115, self.frame.size.height/2-2);
    fbButton.name = @"fb";
    fbButton.zPosition = 2;

    fbToggleNo = [SKSpriteNode spriteNodeWithTexture:toggle_no_texture];
    fbToggleNo.position = CGPointMake(self.frame.size.width/2 - 50, self.frame.size.height/2-2);
    fbToggleNo.size = CGSizeMake(fbToggleNo.size.width/3, fbToggleNo.size.height/3);
    fbToggleNo.name = @"fbno";
    fbToggleNo.zPosition = 2;

    fbToggleYes = [SKSpriteNode spriteNodeWithTexture:toggle_yes_texture];
    fbToggleYes.position = CGPointMake(self.frame.size.width/2 - 70, self.frame.size.height/2-2);
    fbToggleYes.name = @"fbyes";
    fbToggleYes.zPosition = 2;

    int hpBuffer = 40;
    int hpZ = 2;

    home = [SKSpriteNode spriteNodeWithTexture:home_texture];
    home.position = CGPointMake(hpBuffer, self.frame.size.height - hpBuffer);
    home.zPosition = hpZ;
    home.name = @"home";

    play = [SKSpriteNode spriteNodeWithTexture:play_texture];
    play.position = CGPointMake(self.frame.size.width - hpBuffer, self.frame.size.height - hpBuffer);
    play.zPosition = hpZ;
    play.name = @"play";

    [self addChild:bg];
    [self addChild:wbox];
    [self addChild:gamecenter];
    [self addChild:home];
    [self addChild:play];

    [self addChild:fbButton];
    [self addChild:fbToggleNo];

    [self addCredits];
    [self addStory];
}

-(void) addCredits{
    /* images */

    int cmbZ = wbox.zPosition + 1;
    int cmbY = wbox.position.y;
    int cmbXUnit = 132;
    int cmbX = self.frame.size.width/2 - (3*cmbXUnit)/2 + 20;
    int cmbWidth = 40;

    chance  = [SKSpriteNode spriteNodeWithTexture:chance_texture];
    max = [SKSpriteNode spriteNodeWithTexture:max_texture];
    bryce  = [SKSpriteNode spriteNodeWithTexture:bryce_texture];

    chance.zPosition = cmbZ;
    max.zPosition = cmbZ;
    bryce.zPosition = cmbZ;

    chance.position = CGPointMake(cmbX+cmbXUnit*0, cmbY+3);
    max.position = CGPointMake(cmbX+cmbXUnit*1 + 10, cmbY);
    bryce.position = CGPointMake(cmbX+cmbXUnit*2 + 10, cmbY+5);

    chance.size = CGSizeMake(cmbWidth, (chance.size.height/chance.size.width)*cmbWidth);
    max.size = CGSizeMake(cmbWidth, (max.size.height/max.size.width)*cmbWidth);
    bryce.size = CGSizeMake(cmbWidth, (bryce.size.height/bryce.size.width)*cmbWidth);

    [self addChild:chance];
    [self addChild:max];
    [self addChild:bryce];

    /* names */

    int cmb_nameXUnit = 30;
    int cmb_nameY = wbox.position.y - 10;
    int cmb_nameFontSize = 18;

    chance_name = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    max_name = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    bryce_name = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];

    chance_name.text = @"Chance Daniel";
    max_name.text = @"Max Hudson";
    bryce_name.text = @"Bryce Daniel";

    chance_name.fontColor = [SKColor blackColor];
    max_name.fontColor = [SKColor blackColor];
    bryce_name.fontColor = [SKColor blackColor];

    chance_name.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;
    max_name.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;
    bryce_name.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;

    chance_name.position = CGPointMake(chance.position.x + cmb_nameXUnit, cmb_nameY);
    max_name.position = CGPointMake(max.position.x + cmb_nameXUnit, cmb_nameY);
    bryce_name.position = CGPointMake(bryce.position.x + cmb_nameXUnit, cmb_nameY);

    chance_name.fontSize = cmb_nameFontSize;
    max_name.fontSize = cmb_nameFontSize;
    bryce_name.fontSize = cmb_nameFontSize;

    chance_name.zPosition = cmbZ;
    max_name.zPosition = cmbZ;
    bryce_name.zPosition = cmbZ;

    [self addChild:chance_name];
    [self addChild:max_name];
    [self addChild:bryce_name];

    /* roles */

    int cmb_roleY = wbox.position.y - 25;
    int cmb_roleFontSize = 11;

    chance_role = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    max_role = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    bryce_role = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];

    chance_role.text = @"Programmer";
    max_role.text = @"Programmer";
    bryce_role.text = @"Graphic Designer";

    chance_role.fontColor = [SKColor darkGrayColor];
    max_role.fontColor = [SKColor darkGrayColor];
    bryce_role.fontColor = [SKColor darkGrayColor];

    chance_role.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;
    max_role.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;
    bryce_role.horizontalAlignmentMode = SKLabelHorizontalAlignmentModeLeft;

    chance_role.position = CGPointMake(chance.position.x + cmb_nameXUnit + 19, cmb_roleY);
    max_role.position = CGPointMake(max.position.x + cmb_nameXUnit + 12, cmb_roleY);
    bryce_role.position = CGPointMake(bryce.position.x + cmb_nameXUnit + 6, cmb_roleY);

    chance_role.fontSize = cmb_roleFontSize;
    max_role.fontSize = cmb_roleFontSize;
    bryce_role.fontSize = cmb_roleFontSize;

    chance_role.zPosition = cmbZ;
    max_role.zPosition = cmbZ;
    bryce_role.zPosition = cmbZ;

    [self addChild:chance_role];
    [self addChild:max_role];
    [self addChild:bryce_role];

    /* twitter handles */

    int cmb_handY = wbox.position.y - 40;
    int cmb_handFontSize = 10;

    chance_handle = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    max_handle = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    bryce_handle = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];

    chance_handle.text = @"@ChanceOfThat";
    max_handle.text = @"@max_hud";
    bryce_handle.text = @"@BryceOfLife";

    chance_handle.fontColor = [SKColor darkGrayColor];
    max_handle.fontColor = [SKColor darkGrayColor];
    bryce_handle.fontColor = [SKColor darkGrayColor];

    chance_handle.position = CGPointMake(chance.position.x, cmb_handY);
    max_handle.position = CGPointMake(max.position.x, cmb_handY);
    bryce_handle.position = CGPointMake(bryce.position.x, cmb_handY);

    chance_handle.fontSize = cmb_handFontSize;
    max_handle.fontSize = cmb_handFontSize;
    bryce_handle.fontSize = cmb_handFontSize;

    chance_handle.zPosition = cmbZ;
    max_handle.zPosition = cmbZ;
    bryce_handle.zPosition = cmbZ;

    [self addChild:chance_handle];
    [self addChild:max_handle];
    [self addChild:bryce_handle];

    /* touchzones */

    CGSize cmdL_size = CGSizeMake(120, 70);
    SKColor *cmdL_color = [SKColor clearColor];
    int cmdLZ = 3;
    int cmdLX = cmbX + 40;

    chance_link = [SKSpriteNode spriteNodeWithColor:cmdL_color size:cmdL_size];
    max_link = [SKSpriteNode spriteNodeWithColor:cmdL_color size:cmdL_size];
    bryce_link = [SKSpriteNode spriteNodeWithColor:cmdL_color size:cmdL_size];

    chance_link.position = CGPointMake(cmdLX+cmbXUnit*0, cmbY);
    max_link.position = CGPointMake(cmdLX+cmbXUnit*1 + 10, cmbY);
    bryce_link.position = CGPointMake(cmdLX+cmbXUnit*2 + 10, cmbY);

    chance_link.zPosition = cmdLZ;
    max_link.zPosition = cmdLZ;
    bryce_link.zPosition = cmdLZ;

    chance_link.name = @"c_handle";
    max_link.name = @"m_handle";
    bryce_link.name = @"b_handle";

    [self addChild:chance_link];
    [self addChild:max_link];
    [self addChild:bryce_link];
}

-(void) addStory{

    int stX = self.frame.size.width/2;
    int stZ = 2;
    SKColor *stColor = [SKColor whiteColor];

    story1 = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    story2 = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];
    story3 = [SKLabelNode labelNodeWithFontNamed:@"BebasNeue"];

    story1.text = @"Gon";
    story2.text = @"Help Gon-Gon and his friends get";
    story3.text = @"Back to the time they came from!";

    story1.fontColor = stColor;
    story2.fontColor = stColor;
    story3.fontColor = stColor;

    story1.zPosition = stZ;
    story2.zPosition = stZ;
    story3.zPosition = stZ;

    story1.position = CGPointMake(stX, self.frame.size.height - 55);
    story1.fontSize = 50;

    story2.position = CGPointMake(stX, self.frame.size.height - 95);
    story2.fontSize = 30;

    story3.position = CGPointMake(stX, self.frame.size.height - 120);
    story3.fontSize = 20;

    [self addChild:story1];
    [self addChild:story2];
    [self addChild:story3];
}

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    UITouch *touchUI = [touches anyObject];
    CGPoint touchPoint = [touchUI locationInNode:self];
    SKNode *touchNode = [self nodeAtPoint:touchPoint];

    if([touchNode.name isEqualToString:@"home"]){
        StartViewController *svc = [[StartViewController alloc] initWithSize:self.size];
        SKTransition *fade = [SKTransition fadeWithColor :[SKColor blackColor] duration:0.4];
        [self.view presentScene:svc transition:fade];
    }

    if([touchNode.name isEqualToString:@"play"]){
        gameViewController *gvc = [[gameViewController alloc] initWithSize:self.size];
        SKTransition *fade = [SKTransition fadeWithColor :[SKColor blackColor] duration:0.4];
        [self.view presentScene:gvc transition:fade];
    }

    if([touchNode.name isEqualToString:@"gc"]){
        NSDictionary * dict = [[NSDictionary alloc]initWithObjectsAndKeys:[NSNumber numberWithBool:1], @"showGC", nil];

        [[NSNotificationCenter defaultCenter]postNotificationName:@"kNotificationUpdateBannerView" object:self userInfo:dict];
    }

    if([touchNode.name isEqualToString:@"c_handle"]){
        NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"twitter:///user?screen_name=ChanceOfThat"]];
        int worked = [[UIApplication sharedApplication] openURL:urlApp];
        if(!worked){
            NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"https://twitter.com/#!/ChanceOfThat"]];
            [[UIApplication sharedApplication] openURL:urlApp];
        }
    }

    if([touchNode.name isEqualToString:@"m_handle"]){
        NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"twitter:///user?screen_name=max_hud"]];
        int worked = [[UIApplication sharedApplication] openURL:urlApp];
        if(!worked){
            NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"https://twitter.com/#!/max_hud"]];
            [[UIApplication sharedApplication] openURL:urlApp];
        }
    }

    if([touchNode.name isEqualToString:@"b_handle"]){
        NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"twitter:///user?screen_name=BryceOfLife"]];
        int worked = [[UIApplication sharedApplication] openURL:urlApp];
        if(!worked){
            NSURL *urlApp = [NSURL URLWithString: [NSString stringWithFormat:@"%@", @"https://twitter.com/#!/BryceOfLife"]];
            [[UIApplication sharedApplication] openURL:urlApp];
        }
    }
}

@end