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DrBrass
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Joined: Sep 13, 2012
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Can we adjust for DST?	Reply to this Post Reply with Quote
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I have built an iPhone app that uses the RSS feed from my calendar to populate a table showing upcoming events. The problem is that every event is automatically set to Standard Time in my timezone. When reading on the web, it looks fine, but the iPhone automatically adjusts for DST and therefore, the time shown on the app is 1 hour after the event actually starts. Is there any way to remedy this? Some option to show the event occurs during DST?

[Apr 7, 2013, 6:56:54 PM] [50.26.88.208]

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support
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Joined: Aug 9, 2022
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Re: Can we adjust for DST?	Reply to this Post Reply with Quote
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If an event on your calendar happens at on Day X at 1PM, then it should happen at 1PM regardless of DST or not. For example, the Nightly News is always on at 6PM, regardless of whether or not we are in DST.

Internally, our servers run GMT, and (depending on the country and timezone you are in) we will take DST (if observed) into account when sending event reminders.

I'm not sure how you are constructing the dates on your iOS app, but if you can't force an event to be created with the time you specific (without auto-adjusting) then you would need to determine in DST is in effect and adjust accordingly. This is hugely complicated as it varies across the globe. I would strongly recommend more research on the iOS side of things.
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Marc Higgins
Support Associate, localendar.com
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[Apr 8, 2013, 9:02:46 PM] [24.189.166.34]

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DrBrass
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Re: Can we adjust for DST?	Reply to this Post Reply with Quote
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Basically the issue is your RSS Feeds display one time in the pubDate while the calendar displays the actual time an event occurs. Check out http://www.localendar.com/public/DrBrass compared with the feed http://www.localendar.com/public/DrBrass?style=D4, and you will see the time in the RSS does not match the time on the calendar.

[May 25, 2013, 4:11:45 AM] [50.26.12.157]

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support
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Re: Can we adjust for DST?	Reply to this Post Reply with Quote
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I'm sorry, but I still don't follow. I look at the HTML version of your calendar, and picked out a few items:

7 pm - 8 pm
Wed. night Bible Study & Devo
and
9:30 am - 11:30 am
AM Bible Class & Worship

The corresponding raw RSS XML for these items is:

<item>
<title><![CDATA[Wed. night Bible Study & Devo]]></title>
<description><![CDATA[(Wed, 29 May 2013 7 pm - 8 pm CST)
<p>Classes for all ages and short devotional period.</p>]]></description>
<pubDate>Wed, 29 May 2013 19:00:00 CST</pubDate>
</item>

and

<item>
<title><![CDATA[AM Bible Class & Worship]]></title>
<description><![CDATA[(Sun, 02 Jun 2013 9:30 am - 11:30 am CST)
<p>We would love for you to join us for Bible class and worship.</p>]]></description>
<pubDate>Sun, 02 Jun 2013 09:30:00 CST</pubDate>
</item>

For the Wed night event, 7PM CST is 19:00 CST and for the AM Bible class, 9:30am is 9:30 CST. The PubDate does reflect the same time shown on the calendar.

Perhaps you can help me understand what I'm missing...
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Marc Higgins
Support Associate, localendar.com
Follow us on Twitter! http://www.twitter.com/localendar_news

[May 28, 2013, 4:51:42 PM] [24.189.166.34]

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DrBrass
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Joined: Sep 13, 2012
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Re: Can we adjust for DST?	Reply to this Post Reply with Quote
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The issue is that you have no option for DST. Therefore, when the pubDate time is listed as CST, but the user is actually now in CDT, their system automatically adds an hour to the time to compensate, causing it to show the wrong time.

This is easily seen in a screenshot from my computer of the exact feed in question. Even though the pubDate lists it as 19:00, because it shows CST instead of CDT, the browser automatically adds an hour to the time to adjust, and shows a start time of 8:00 PM which is 20:00

[May 30, 2013, 4:04:48 AM] [50.26.12.157]

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support
localendar Expert

Joined: Aug 9, 2022
Posts: 6438
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Re: Can we adjust for DST?	Reply to this Post Reply with Quote
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The date is the indicator for DST.
A system should use the event date and its own internal table to calculate that DST is in effect for that region.

That's exactly what we have to do when people import a calendar from Google, for example. We don't get an indicator tell using "This event is in DST", you have to look at the date and the country/location and figure it out.

Have a look at this related discussion on joelonsoftware. One person's (correct) solution?

I've now managed to write an acceptable solution that is correct for all but one hour during the change back from BST (GMT+1) to GMT by checking the current date is within the date/time ranges given at http://wwp.greenwichmeantime.com/time-zone/rules/eu.htm and returning "+0000" or "+0100" accordingly.

http://discuss.joelonsoftware.com/default.asp?joel.3.222492.9
----------------------------------------
Marc Higgins
Support Associate, localendar.com
Follow us on Twitter! http://www.twitter.com/localendar_news

[Jun 6, 2013, 3:09:58 AM] [24.189.166.34]

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