How to call class methods in the iOS simulator with lldb?

Question

I'm trying to debug an iOS app and I'm having problems with lldb in the simulator. Calling class methods doesn't seem to work. Instance methods work fine.

(lldb) po Category
<no result>
(lldb) po [Category class]
error: Couldn't prepare the expression for execution in the target
(lldb) po self
(TagsTableViewController *) $5 = 0x085585a0 <TagsTableViewController: 0x85585a0>

I've tried the 4.3 and 5.1 simulators but both exhibit the same issues.

Everything works fine when debugging on a device.

I'm thinking it might be a bug in lldb but I've found a workaround in the meantime. It's a little awkward but it works: `po [(Class)objc_getClass("ClassName") class]` — devioustree, Mar 27 '12 at 10:36

score 18 · Accepted Answer · answered Jun 12 '12 at 20:12

18

This works. Thanks to @devioustree who answered in a comment above.

Basic command is structured like this:

po [(Class)objc_getClass("ClassName") class]

To invoke someClassMethodHere:

po [[(Class)objc_getClass("ClassName") class] someClassMethodHere]

answered Jun 12 '12 at 20:12

bentford

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score 0 · Answer 2 · answered Dec 01 '15 at 20:08

Adding this to expand on the accepted answer...

If you're trying to assign a new value to a variable in lldb like I was instead of just printing out the value then do something like this...

expr self.myArray = (NSArray*)[[(Class)objc_getClass("NSArray") class] arrayWithObjects:@"valueOne",@"valueTwo",@"etc",nil]

How to call class methods in the iOS simulator with lldb?

2 Answers2

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