Many "getContext()" or one private context = getContext() and use it?

Question

I need context many times in my fragment:

    ...
    account.restore(getContext());
    ...
    dbHelper = new DBHelper(getContext());
    ...
    DiskLruBasedCache.ImageCacheParams cacheParams = new DiskLruBasedCache.ImageCacheParams(getContext(), "CacheDirectory");
    ...
    mImageLoader = new SimpleImageLoader(getContext(), cacheParams);
    ...
    Toast.makeText(getContext(), "err: " + error, Toast.LENGTH_LONG).show();
    ...
    RecyclerView.LayoutManager layoutManager = new CustomLayoutManager(getContext());
    ...

Or should I initialize it once and then use it.

What is best way ?

`private Context = getContext()` won't work – OneCricketeer Oct 10 '17 at 17:08 — OneCricketeer, Oct 10 '17 at 17:08
`private Context = getContext()` will not compile. – Petter Hesselberg Oct 10 '17 at 17:42 — Petter Hesselberg, Oct 10 '17 at 17:42

Petter Hesselberg · Answer 1 · 2017-10-10T17:58:12.733

2

This is mostly a matter of preference. You can call getContext() wherever you need one -- no cause to be worried about perf overhead. Or you can assign a private Context context field in your onCreate method. Or, if a particular method has multiple uses, create a local variable.

If getContext was potentially slow, then you should definitely have stashed it, but it's really just a simple accessor (almost -- it does one bit of indirection internally).

Go with whatever you find most readable.

edited Oct 10 '17 at 17:58

answered Oct 10 '17 at 17:23

Petter Hesselberg

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The OP is already using `getContext()`, just asking if it made sense to stash it. – Petter Hesselberg Oct 10 '17 at 17:31
That's why Cricket_007 mentioned that simply getContext() won't work. You can also check here https://stackoverflow.com/a/20464697/7337723 – Kartik Shandilya Oct 10 '17 at 17:32
What are you talking about? `getContext()` works fine in a `Fragment`. It returns a reference to the owner activity (via `FragmentHostCallback`), so it's the same thing as calling `getActivity()`. – Petter Hesselberg Oct 10 '17 at 17:38
Fragment.getContext: https://developer.android.com/reference/android/app/Fragment.html#getContext() – Petter Hesselberg Oct 10 '17 at 17:45

score 0 · Answer 2 · edited Jun 19 '18 at 19:54

In this case, it would be best to call it once and use it. This is due to the fact that the execution will be faster without the extraneous function calls. It would be common to see

Context context = getContext();

I have done this many times and stored it to a variable in a class. In that case though it looks like this:

class SomeClass {
   Context context;
   @Override
   void onCreate(){
      context = getContext();
   }
}

Many "getContext()" or one private context = getContext() and use it?

2 Answers2