#nslog

How to: Warning: "format not a string literal and no format arguments"

Warning: "format not a string literal and no format arguments"

Since upgrading to the latest Xcode 3.2.1 and Snow Leopard, I’ve been getting the warning

“format not a string literal and no format arguments”

from the following code:

NSError *error = nil; if (![self.managedObjectContext save:&error]) { NSLog([NSString stringWithFormat:@"%@ %@, %@", errorMsgFormat, error, [error userInfo]]); }

If

How to: What is the Objective-C equivalent for "toString()", for use with NSLog?

What is the Objective-C equivalent for "toString()", for use with NSLog?

Is there a method that I can override in my custom classes so that when

NSLog(@"%@", myObject)

is called, it will print the fields (or whatever I deem important) of my object? I guess I’m looking for the Objective-C equivalent of Java’s toString().

Answer: What is the Objective-C equivalent for "toString()", for use with…

Fixed How to print out the method name and line number and conditionally disable NSLog? #dev #it #asnwer

How to print out the method name and line number and conditionally disable NSLog?

I’m doing a presentation on debugging in Xcode and would like to get more information on using NSLog efficiently.

In particular, I have two questions:

is there a way to easily NSLog the current method’s name / line number?

is there a way to “disable” all NSLogs easily before compiling for release code?

Answer: How…

How to: How to print out the method name and line number and conditionally disable NSLog?

How to print out the method name and line number and conditionally disable NSLog?

I’m doing a presentation on debugging in Xcode and would like to get more information on using NSLog efficiently.

In particular, I have two questions:

is there a way to easily NSLog the current method’s name / line number?

is there a way to “disable” all NSLogs easily before compiling for release code?

Answer: How…

It is very common when debugging to want to view the various parameters of view frames. But since these are structs, there are no obvious % parameters in an NSLog statement to pass to get to the various components. It gets painful fast:

`NSLog(@"view frame x: %.0f y: %.0f", self.view.frame.origin.x, self.view.frame.origin.y);`

But it turns out that there are a great set of functions to turn these struct parameters into an NSString. I couldn't remember where and this Stack Overflow Post got me headed in the right direction:

NSLog(@"%@", NSStringFromCGRect(self.view.frame));

from the Documentation, the following are available.

NSStringFromCGAffineTransform NSStringFromCGPoint NSStringFromCGRect NSStringFromCGSize NSStringFromUIEdgeInsets NSStringFromUIOffset

Also, do not forget about the ever helpful:

NSLog(@"%s", __PRETTY_FUNCTION__);