How to passing class argument to selector in objective C?

Question

I want to set the class tile value by click on the button

if click onPlus it will have a string value = @"+"
if click onMinus it will have a string value = @"-"

here are the code

//Class Tile

@interface Tile : TouchableNode {
     NSString *val;
}

-(void) setVal:(NSString *)v
{
    val = v;
}

-(NSString *) getVal
{
    return val;
}

And the in another class

I have a code like this

for(Tile *tile in player)
{
    if (tile.getVal == @"P") {
        if (pauseStatus == 0) {
            pauseStatus = 1;

            [[CCDirector sharedDirector] pause];
            CGSize size = [[CCDirector sharedDirector] winSize];
            pauseLayer=[[CCLayer alloc] init];
            pauseLayer.anchorPoint=ccp(0,0);
            pauseLayer = [CCLayerColor layerWithColor: ccc4(0, 0, 255, 125) width: 300 height: 150];
            pauseLayer.position = ccp(size.width/2, size.height/2);       
            pauseLayer.isRelativeAnchorPoint = YES;
            [self addChild: pauseLayer z:8];

            //Here are 2 two button that when user click it will have @"+" value or @"-"
            plusBtn = [CCMenuItemImage itemFromNormalImage:@"plus.png" selectedImage:@"plus.png"     target:self selector:@selector(onPlus:)];
            minusBTn = [CCMenuItemImage itemFromNormalImage:@"minus.png" selectedImage:@"minus.png"      target:self selector:@selector(onMinus:)];

            pauseMenu = [CCMenu menuWithItems:plusBtn, minusBTn, nil];
            [pauseMenu alignItemsHorizontally];
            [self addChild:pauseMenu z:10];
        }
    }
}

and I have onPlus & onMinus method that I want to send object tile to that method

-(void)onPlus:(Tile *) set
{
    NSString *plus = @"+";
    [set setVal:plus];
}

-(void)onMinus:(Tile *) set
{
    NSString *minus = @"-";
    [set setVal:minus];
}

How to pass the object tile to the method?? Or it have another way to make it??

score 0 · Answer 1 · answered Jan 05 '12 at 15:47

If you want to send a Tile object to your onPlus handler, just subclass CCMenuItemImage and make a Tile property:

@interface MyCustomCCMenuItemImage : CustomCCMenuItemImage
@property (nonatomic, retain) Tile* tile;
@end

Here's a rough example of what your code might look like:

- (void)someMethod
{

    for(Tile *tile in player)
    {
        plusBtn = [MyCustomCCMenuItemImage itemFromNormalImage:@"plus.png"   selectedImage:@"plus.png" target:self selector:@selector(onPlus:)];
        plusBtn.tile = tile ;
    }

}

//Your handler
-(void)onPlus:(id)sender
{
    Tile *myTile = sender.tile;
}

score 0 · Accepted Answer · answered Jan 05 '12 at 15:50

0

CCMenuItemImage inherits from CCNode, which has a void* userData property. If you assign tile to userData, you could fetch it back from the (id)sender in your onPlus/onMinus methods.

plusBtn = [CCMenuItemImage itemFromNormalImage:@"plus.png" selectedImage:@"plus.png"     target:self selector:@selector(onPlus:)];
plusBtn.userData = (void*)tile; // You may need a bridge cast in ARC
minusBTn = [CCMenuItemImage itemFromNormalImage:@"minus.png" selectedImage:@"minus.png"      target:self selector:@selector(onMinus:)];
minusBTn.userData = (void*)tile;

-(void)onPlus:(id)senderObj {
    CCNode *sender = (CCNode*)senderObj;
    Tile *myTile = (Tile*)sender.userData; // Again you may need a bridge cast here
}

answered Jan 05 '12 at 15:50

Sergey Kalinichenko

714,442
84
1,110
1,523

Ah... by the way when the pause layer is up with those two button .The screen is pause but the program still running... In other words I want to wait for the button action so that after I touch the button... the program can run continuously... So I want to know a wait for action funtion with the button too.. – Bancha Rojkittisakul Jan 06 '12 at 02:55
If the program is still running, wouldn't it just work the way that you coded it? Did you get a chance to try the `userData` trick? – Sergey Kalinichenko Jan 06 '12 at 04:27
Your code is work but it set to @"+" or @"-" after my function have finish.. so I get the value @"P" that I don't want it to be.So I want to wait until I press the button. – Bancha Rojkittisakul Jan 06 '12 at 06:20
The lastest 2 comment that I ask is a new question... The question is "How to wait until the CCmenuItemImage was press???" – Bancha Rojkittisakul Jan 06 '12 at 06:30
http://stackoverflow.com/questions/8754362/how-to-wait-until-the-ccmenuitemimage-is-press-in-objective-c – Bancha Rojkittisakul Jan 06 '12 at 06:48

score 0 · Answer 3 · edited Jan 05 '12 at 15:58

0

For string comparisons, you're better off using

[tile.getVal isEqualToString:@"P"]

Since the method you use only works if it's the exact same string (in the same memory location), as opposed to an equivalent string elsewhere .

edited Jan 05 '12 at 15:58

COD3BOY

11,964
1
38
56

answered Jan 05 '12 at 15:53

ObjectiveC-oder

342
1
5

This is a valuable observation, but comments is a better place for it, because it does not the OP's question. – Sergey Kalinichenko Jan 05 '12 at 16:01

How to passing class argument to selector in objective C?

3 Answers3