iPhone: I am having trouble with memory iteratively building up

I am having trouble with memory building up a开发者_开发技巧nd am not able to empty it once I am done with it. When I look at the diagnostic tool ": Allocations: Instruments: Object summary: statistics", the memory is just continuously building up.

example:

for (int i=0; i<100000; i++){
    UILabel *lblPost = [[UILabel alloc] initWithFrame:CGRectMake(x,y,w,d)];
    [lblPost setText: "Hello World"];
    [self.view addSubview: lblPost];

    // tried each of the following
    //[lblPost dealloc]; //neither work to clear memory it just builds
    //[lblPost release]; //
}

--> Do I need to seperate CGRect out and clear that.

--> (I know I can just keep writing to one label, this is a simplified version where in the bigger version, one label would not work so easily. )

--> (I find it hard to believe that I can not create an object and then destroy it 10000 or 100000000 times over. In standard C, I can accomplish this with memory-blocks by using "free()" )

The view you are adding your label to is retaining it, that's why each none of the labels is deallocated (even if you send release message)

Maybe i really don't understand what you're trying to do, but your each indiviual object you'r allocating is retained in the view. Let me try to explain it in the code:

 for (int i=0; i<10000; i++){
  UILabel *lblPost = [[UILabel alloc] initWithFrame:CGRectMake(x,y,w,d)];
 // lblPost now has a retain count of 1, as you alloc'd it, you'll have to release it!
  [lblPost setText: "Hello World"];
  [self.view addSubview: lblPost];
 // lblPost now has a retain count of 2, as adding to the view adds a reference to it
  [lblPost release]
 // you alloc'd it, now you should release it. it now has a retain count of 1, which means it's in the ownerhsip of the self.view
}

Now, when you release or free self.view, the lblPost objects should be released as well

Why are you allocating memory for 10000 UILabels and adding them as a subview exactly? That's iPhone torture. The items in bold cause your surge in memory. Plus you're releasing none of them.

Also - never ever ever call dealloc yourself - dealloc is called automatically when you release something.

This is fun! I have decided to jump in. I posted this in my comments but here it is again:

I think madhu misunderstood the [lblPost release]. This "release" only applies to the lblPost instance. Not the ones retained by self.view... etc. So you still have 10000 label retained by self.view...

So, you create 10000 instances of lblPost and then release all of them (10000) by this line [lblPost release] in your for loop. That is just fine. But then in your for loop you also have this line [self.view addSubview: lblPost]. This line will add 10000 instances to your self.view. And they are the reason why your system crashed.

for (int i=0; i<10000; i++){
    UILabel *lblPost = [[UILabel alloc] initWithFrame:CGRectMake(x,y,w,d)];
    [lblPost setText: "Hello World"];
    [self.view addSubview: lblPost];

    [lblPost release];
    //You should release after adding it to your view


}