Q:

How to see the value of an object property in Xcode at a breakpoint

I have a parent node contain all object :
SKNode* _moving;
_moving = [SKNode node];
[self addChild:_moving];
...
[_moving addChild:spritenodetexture];

now I want to check the speed value of "_moving" which is "_moving.speed";
So I set a break point at that line of condition: 
if (_moving.speed > 0) {

How do I know the value of  "_moving.speed" at that point ? Look into debug windows, I only see the address, postion, etc., but no value! Does Xcode Debug has tool to see it but I don't know ?
(I am using SpriteKit in Xcode)

A:

Modern versions of Xcode use LLDB.
The easiest way to inspect scoped variables during a breakpoint is to use the "Variables View" from within the Debug Area: View > Debug Area > Show Debug Area and then click the "Show Variables View" button (i.e., second-to-last icon in the lower right-hand corner). You can then explore the tree of variables in scope.

Optionally (though I've personally had varied success) you can simply hover your mouse cursor over the variable in question and Xcode should pop up a tool tip with some options.
You can also issue LLDB commands from the console itself. To print out your variable, execute the following command:
print [_moving speed]

Here's a handy list of LLDB commands and their older GDB counterparts.

