How to change time and timezone in iPhone simulator?

Question

How do I change time and time zone in the iPhone simulator?

Answer 1

I'm guessing it uses your system timezone, so changing the TZ in System Preferences would probably do the trick

Answer 2

Restart the Simulator after changing the system date time preferences and you shall see the changes reflected. It worked for me.

Answer 3

It would be useful if Apple provided a "Simulate date" as they provided a "Simulate Location" menu. What I do is set a breakpoint immediately after getting the date (saving it in a variable) and then modify the value. Or just modify the spot where I check for a date change and make it return true.

Answer 4

When changing the timezone, I found the easiest way to do it was by clicking the clock in the menubar. And then selecting "Open Date & Time Preferences" then select the tab Time Zone.

Alternatively System Preferences -> Date and Time and select the tab Time Zone.

Just a pointer for anyone that might not know their way around OSX.

Answer 5

This is an old thread but it is closest to my question. I need to simulate time zone for Europe, this method works for me. Go to 'TimeZone' tap instead of 'Date&Time' tap. Uncheck the 'Set time zone automatically using current location' box and slide the vertical rectangle bar (with blue dot on it) to simulate your system time.

Answer 6

I have proposed an automatic solution to the problem of changing the time that includes hacky method swizzling: https://stackoverflow.com/a/34793193/829338. I assume that should also work for changing the time zone accordingly.

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I needed to test my app automatically, which required changing the sys time. I did, what Tom suggested: happy hacky method swizzling.

For demonstrative purposes, I only change [NSDate date] but not [NSDate dateWithTimeIntervalSince1970:].

First your need to create your class method that serves as the new [NSDate date]. I implemented it to simply shift the time by a constant timeDifference.

int timeDifference = 60*60*24; //shift by one day
NSDate* (* original)(Class,SEL) = nil;

+(NSDate*)date{
    NSDate* date = original([NSDate class], @selector(date));
    return [date dateByAddingTimeInterval:timeDifference];
}

So far, pretty easy. Now comes the fun part. We get the methods from both classes and exchange implementation (it worked for me in the AppDelegate, but not in my UITests class). For this you will need to import objc/runtime.h.

Method originalMethod = class_getClassMethod([NSDate class], @selector(date));
Method newMethod = class_getClassMethod([self class], @selector(date));

//save the implementation of NSDate to use it later
original  = (NSDate* (*)(Class,SEL)) [NSDate methodForSelector:@selector(date)];

//happy swapping
method_exchangeImplementations(originalMethod, newMethod);

Answer 7

My build server is UTC and some of my unit tests needed the timezone to be PST. Using a category on NSTimeZone you can override Apple's implementation to use your code. Works for swift only projects too.

//NSTimeZone+DefaultTimeZone.h
#import <Foundation/Foundation.h>

@interface NSTimeZone (DefaultTimeZone)

+(NSTimeZone *)defaultTimeZone;

@end

//NSTimeZone+DefaultTimeZone.m
#import "NSTimeZone+DefaultTimeZone.h"

@implementation NSTimeZone (DefaultTimeZone)

+(NSTimeZone *)defaultTimeZone
{
    return [NSTimeZone timeZoneWithName:@"America/Los_Angeles"];
}

@end