how use getContentResolver in a class without activity?

Question

my class looks like this:

public class sendInformation{

  public void test() throws Exception {
    Uri uri = SuspiciousActivityTable.CONTENT_URI;
    getContentResolver().update(uri, values2, where,new String[]{"Null"});
    }
  }
}

but it say getContentResolver() doesn't exist, I know I need a Context or Activity to make this work but how do I get the correct Context here?

`public void class` That doesn't make any sense. Classes can't have a return type. — A--C, Feb 25 '13 at 22:49
Ok so this class get called from another class which extends activity so i supposed to pass that context how i can do that? — user2033349, Feb 25 '13 at 22:59
I'm really new in this, i call the method like this from my activity class test("how pass the context?") how i pass the context from my activity class to test();? — user2033349, Feb 25 '13 at 23:12

A--C · Accepted Answer · 2013-02-25T23:17:39.710

You will need to pass off a Context, even the ContentResolver class needs a valid context to be instantiated.

Simplest way is as an argument to the method:

public void test(Context context) throws Exception {
    Uri uri = SuspiciousActivityTable.CONTENT_URI;
    context.getContentResolver().update(uri, values2, where,new String[]{"Null"});
  }

And to call: (assuming that the class that contains test is instantiated and your Activity's name is MyActivity <- Replace with the Activity name you're calling test() from)

try{
    sendInformationInstanceVariable.test (MyActivity.this);
}
catch (Exception e)
{
 e.printStackTrace();
}

MyActivity.this can be shortened to just this if you're not calling test() from inside an anonymous inner class.

Also, if your class really doesn't have a good reason to be instantiated, consider making test() a static method, like this:

public static void test(Context context) throws Exception {
        Uri uri = SuspiciousActivityTable.CONTENT_URI;
        context.getContentResolver().update(uri, values2, where,new String[]{"Null"});
      }

Then from your Activity, you call this method without needing an instance:

try{
    sendInformation.test (MyActivity.this);
}
catch (Exception e)
{
 e.printStackTrace();
}

Lastly, throwing Exception is bad practice, do don't do it without good reason and if you do have a good reason, be as specific as possible.

thanks a lot i was so confusing about this, is easy when you understand what are you doing thanks :) — user2033349, Feb 25 '13 at 23:59
how would you do it in a service? My understanding is that you _cannot_ pass context to a service. — roberto tomás, Mar 28 '16 at 15:31

score 9 · Answer 2 · edited Mar 10 '16 at 18:01

Somewhere between where your application starts (and you have access to getApplicationContext()) and the point where you call test(), you'll need to pass in a Context to your sendInformation class. I would look at what lifecycle your sendInformation class has and compare it to the various Android components (Application, Activity, Fragment) and use the appropriate context from there:

Application: getApplicationContext()
Activity: this (as Activity extends Context)
Fragment: getActivity()

how use getContentResolver in a class without activity?

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