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Android Build a Weather App (2015) Hooking Up the Model to the View Setting the Weather Icon

amir baldiga
amir baldiga
2,530 Points
Posted by amir baldiga
amir baldiga
2,530 Points

when i run the app i can't get normal time display

when i try to run the app i get this message

java.lang.NullPointerException: id == null

my CurrentWeather method:

  public String getRealTime(){
    SimpleDateFormat format = new SimpleDateFormat("k:mm", Locale.US);
    format.setTimeZone(TimeZone.getTimeZone(getTimeZone()));
    Date day = new Date(getTime() * 1000);


    return  format.format(day);
}

and the call in the Main Activity:

mTimeLabel.setText("At" + mWeather.getRealTime() + "");

2 Answers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi there,

What is pointing to null when you run your code?

I've got a version of this app that is a little more developed because I finished the course - a long time ago, hence my lack of recollection!!

So, the getRealTime() method (my code has getFormattedTime()) looks exactly like what you've got, so that's not where the problem is.

I suspect the null is coming from the JSON - can you add a breakpoint near where this is called in MainActivity? The mWeather variable needs to hold something; adding a breakpoint would check that. In my code, it creates an instance of the Forecast class then sets a few labels lik e mTemperatureLabel then mTimeLabel. We need to check that mWeather holds something meaningful - the breakpoint will do that.

Steve.

amir baldiga
amir baldiga
2,530 Points
amir baldiga
amir baldiga
2,530 Points

got it figured by using a simple if() in the getRealTime to disallow a situation of null to be returned

thank you very much for helping me again :)

Steve Hunter
Steve Hunter
57,712 Points

That's a good fix, yes. You may run into problems with that further in the project. Feel free to ask if you need any help !

Steve.