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Android

Pieter-Andries van der Berg
Pieter-Andries van der Berg
7,468 Points

Convert to celsius

Hello guys and girls,

Im following the stormy app.

what would be a good way because the data we are getting is in Fahrenheit i want it to display in degrees celcius

6 Answers

Seth Kroger
Seth Kroger
56,414 Points

IIRC you can add "&units=si" or "&units=auto" to the end of the query to get Celsius/metric or the correct units for your current location respectively.

Dane Parchment
MOD
Dane Parchment
Treehouse Moderator 11,077 Points

I am not familiar with any Android libraries since I haven't actually done any android development. But you can manually convert the temperature pretty straightforwardly using some simple math.

The Formula for Fahrenheit to Celsius: Tc = (Tf - 32) x 5 / 9

Where Tc = the final temperature Where Tf = the temperature in Fahrenheit


Example: 50deg Fahrenheit in Deg Celsius = (50 - 32) x 5 / 9 = 10.00 deg Celcius

Pieter-Andries van der Berg
Pieter-Andries van der Berg
7,468 Points

okay thanks for that naother question the time in the app is in PM how can i convert it to 24H format

Dane Parchment
Dane Parchment
Treehouse Moderator 11,077 Points

Again, I don't know if there are any libraries available that will handle this for you, or if you can customize the data you receive, but to convert a 12 hour clock to a 24 hour clock you need to:

  1. If the time is am, remove the AM, and append a leading 0 if the digit is a single number

    1. Example: 9:30am -> 09:30 (single digit)
    2. Example: 10:45am -> 10:45 (double digit)
  2. If the time is pm, remove the PM, and add 12 to the number

    1. Example: 9:30pm -> 21:30
Pieter-Andries van der Berg
Pieter-Andries van der Berg
7,468 Points

i successfully converted the time with the simple date formatted to "HH:mm"

But my phone time is on 17:08 (5:08PM) but the app says 16:08 (4:08PM)

its not getting the +1 hour of my timezone for some reason. ( living in The Netherlands)

using this : formatter.setTimeZone(TimeZone.getTimeZone(timeZone));

alastair cooper
alastair cooper
30,617 Points

Hi

I used a regular expression string to find any numeric value followed by ?F. Then I parsed the number part and changed it to Centigrade with the formula and replaced 'F' with 'C' I have posted the function for you here. I had system print lines in to test it which are commented out.

hope this helps

    public String switchSummaryFahrenheitForCentigrade(String summary) {
        String tempFound = null;
        //System.out.println(summary);
        Pattern p = Pattern.compile("\\d+\\WF");
        Matcher m = p.matcher(summary);
        while(m.find()) {
            tempFound = m.group();
            tempFound = tempFound.substring(0,tempFound.length()-2);
            //System.out.println(tempFound);
        }
        if(tempFound != null) {
            int newTemp = Math.round((Integer.valueOf(tempFound) - 32) * 5/9);
            //System.out.println(newTemp);
            summary = summary
                    .replace(tempFound,String.valueOf(newTemp))
                    .replace("F ","C ");
        }
        //System.out.println(summary);
        return summary;
    }

NOTE: in a regex tester the actual pattern is \d+\WF but you need to escape the backslashes in java (so use 2 of them)

NOTE: This will only change the last instance of the temperature (it will catch them all but the while loop keeps re-writing the value found and only passes on the last value to the rest of the function) However, so far there has never been more than one mention of a temperature in the daily or hourly summaries. Note also, It will also only catch temperatures if they are followed by °F. I tried it without but it converts all numerical data like inches of rain and snow etc. Again, so far this has not mattered.

Overall this is a solution that has served me well so far but is not perfect. I wish I had read the Dark Sky information properly before I started if the last answer is true and I can just ask for the units in Centigrade! That would be easier and never produce errors

Here's an old solution I did when I did the course some time ago. https://teamtreehouse.com/community/solution-for-converting-the-code-into-celsius