What is my context and where do I find it?

Question

I asked a similar question earlier but i don't understand what to do, I also have read other solutions like: What is a NullPointerException, and how do I fix it? I still don't know what to do, please help:

According to what I understand is that my context = null; and I am not sure why, and how to fix it...

I wrote a UniversImageLoader.class to be able to load images over several activities. Now I have initiated it in all my activities, but in my UIL class, I need to pass a context.

public class UniversalImageLoader {

    private static final int defaultImage = R.drawable.ic_android;
    private Context mContext;

    public UniversalImageLoader(Context context) {
        mContext = context;
    }

    public ImageLoaderConfiguration getConfig(){
        //File cacheDir = StorageUtils.getCacheDirectory(mContext);
        ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(mContext)//<--the error is in this line
                .memoryCacheExtraOptions(480, 800) // default = device screen dimensions
                .diskCacheExtraOptions(480, 800, null)
                .threadPriority(Thread.NORM_PRIORITY - 2) // default
                .tasksProcessingOrder(QueueProcessingType.FIFO) // default
                .denyCacheImageMultipleSizesInMemory()
                .memoryCache(new LruMemoryCache(2 * 1024 * 1024))
                .memoryCacheSize(2 * 1024 * 1024)
                .memoryCacheSizePercentage(13) // default
                .diskCacheSize(50 * 1024 * 1024)
                .diskCacheFileCount(100)
                .diskCacheFileNameGenerator(new HashCodeFileNameGenerator()) // default
                .imageDownloader(new BaseImageDownloader(mContext)) // default
                .defaultDisplayImageOptions(DisplayImageOptions.createSimple()) // default
                .writeDebugLogs()
                .build();

        return config;
    }

in HomeActivity:[in every Activity I call it like this]

private void initImageLoader(){
        UniversalImageLoader universalImageLoader = new UniversalImageLoader(mContext);
        ImageLoader.getInstance().init(universalImageLoader.getConfig());
    }

and in all those activities I call it in the OnCreate method like this:

initImageLoader();

So I have read up, looked at other solutions but can't find an understandable answer...your guidance will be highly appreciated!

just pass this as parameter instead of mContext in your activity . new UniversalImageLoader(this); — dariush f, Jun 01 '19 at 18:43
An error: UniversalImageLoader (android.content.Context) in UniversalImageLoader cannot be applied to the activity — Ben Van Jaarsveld, Jun 01 '19 at 18:49
Ok . if you are in the fragments then you need to pass requireContext() instead. new UniversalImageLoader(requireContext()) — dariush f, Jun 01 '19 at 18:53
Wouldn't it be better (in this specific context) for him to use getApplicationContext() and convert the class into a singleton, considering the fact that it'll be used in multiple activities? — Chrisvin Jem, Jun 01 '19 at 18:59
you're welcome Ben . just push up arrow to indicate it's was useful comment! — dariush f, Jun 01 '19 at 20:26

score 1 · Accepted Answer · edited Jun 02 '19 at 01:35

1

Use this.mContext = context; in constructor so it will pass your context to the context of current class.

And pass getApplicationContext or yourActivityName.this where you are using this class.

If you are using it in fragment use getActivity or getContext.

edited Jun 02 '19 at 01:35

L. F.

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answered Jun 01 '19 at 19:00

Muhmmad Umair

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What is my context and where do I find it?

1 Answers1