[IOS] callback mselector: withobject: afterdelay: problems that do not work and Solutions

This problem has been found for nearly one day. Baidu and Google have been around for a long time, so no one has encountered the same problem?

Both mselector: withobject: afterdelay: And [nst1_timerwithtimeinterval: Invocation: repeats:] have this problem: after the call, after the delay (the same as the delay of 0), the specified @ selecter () is not entered (). Repeated verification found that this phenomenon occurs in the Child thread and can be used normally in the main thread. Therefore, make sure that the callback mselector: withobject: afterdelay: is called in the main thread.
However, we didn't test whether to create an nstimer in the Child thread for latency. It should be okay.
[Nstimer timerwithtimeinterval: Invocation: repeats.
Special implementation
- (void)performSelectorOnMainThread:(SEL)aSelector withObject:(id)anArgument afterDelay:(NSTimeInterval)delay
Method to ensure successful calls in the main thread
// Nsobject_performselectorex.h
@ Interface nsobject (performselectorex)
-(Void) implements mselecw.mainthread :( SEL) aselector withobject :( ID) anargument afterdelay :( nstimeinterval) delay;
@ End
// Nsobject_performselectorex.m
# Import
"Nsobject_performselectorex.h"
@ Implementation nsobject (effecmselectorex)
-(Void) implements mselecw.mainthread :( SEL) aselector withobject :( ID) anargument afterdelay :( nstimeinterval) Delay
{

Nsmethodsignature * Sig = [self
Methodsignatureforselector: aselector];

If (! SIG)
{

Return;
}

Nsinvocation * invo = [nsinvocation
Invocationwithmethodsignature: SIG];
[Invo
Settarget: Self];
[Invo
Setselector: aselector];
[Invo
Setargument: & anargument atindex: 2];
[Invo
Retainarguments];

Nsmethodsignature * sigmt = [invo methodsignatureforselector: @ selector (performselector: withobject: afterdelay :)];

Nsinvocation * invomt = [nsinvocation
Invocationwithmethodsignature: sigmt];
[Invomt
Settarget: invo];
[Invomt
Setselector: @ selector (effecmselector: withobject: afterdelay :)];

Sel arg1 = @ selector (invoke );

Void * arg2 = nil;

Nstimeinterval arg3 = delay;
[Invomt
Setargument: & arg1 atindex: 2];
[Invomt
Setargument: & arg2 atindex: 3];
[Invomt
Setargument: & arg3 atindex: 4];
[Invomt
Retainarguments];
[Invomt
Performselectoronmainthread: @ selector (invoke)
Withobject: Nil
Waituntildone: No];
}
@ End