Checking if in-app purchases are owned in Android on first launch

Question

I am trying to detect if any of the in-app purchases are owned by the user when the app is started on first try to renew the Pro mode of the app using SharedPreferences. The following code is unfortunately not working :(

        if (version.equals("null")) { //checking version of the app, if it is unset equals first launch
        SharedPreferences.Editor editor = appinfo.edit();
        version = currentversion;
        editor.putString("version", version);
        editor.apply();

        IabHelper.QueryInventoryFinishedListener mReceivedInventoryListener
                = new IabHelper.QueryInventoryFinishedListener() {
            public void onQueryInventoryFinished(IabResult result,
                                                 Inventory inventory) {

                if (mHelper == null) return; //IabHelper mHelper;
                Purchase purchase = Inventory.getPurchase("sku1");
                Purchase purchase2 = Inventory.getPurchase("sku2");
                Purchase purchase3 = Inventory.getPurchase("sku3");
                if (purchase != null || purchase2 != null || purchase3 != null) {
                    final SharedPreferences ispro = getApplicationContext().getSharedPreferences("ispro", 0);
                    SharedPreferences.Editor editor = ispro.edit();
                    editor.putInt("ispro", 1);
                    editor.apply();
                }
            }
        };

        startActivity(new Intent(MainPage.this, Changelog.class));

EDIT1: After some edits the code now looks like this:

final List<String> skus = Arrays.asList("sku1", "sku2", "sku3");
    if (version.equals("null")) {
        SharedPreferences.Editor editor = appinfo.edit();
        version = currentversion;
        editor.putString("version", version);
        editor.apply();

        mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
            public void onIabSetupFinished(IabResult result) {

                if (!result.isSuccess()) {

                }


                if (mHelper == null) return;

                mBroadcastReceiver = new IabBroadcastReceiver(MainPage.this);
                IntentFilter broadcastFilter = new IntentFilter(IabBroadcastReceiver.ACTION);
                registerReceiver(mBroadcastReceiver, broadcastFilter);

                IabHelper.QueryInventoryFinishedListener mReceivedInventoryListener
                        = new IabHelper.QueryInventoryFinishedListener() {
                    public void onQueryInventoryFinished(IabResult result,
                                                         Inventory inventory) {
                        if (mHelper == null) return;
                        Purchase purchase = Inventory.getPurchase("sku1");
                        Purchase purchase2 = Inventory.getPurchase("sku2");
                        Purchase purchase3 = Inventory.getPurchase("sku3");
                        if (purchase != null || purchase2 != null || purchase3 != null) {
                            final SharedPreferences ispro = getApplicationContext().getSharedPreferences("ispro", 0);
                            SharedPreferences.Editor editor = ispro.edit();
                            editor.putInt("ispro", 1);
                            editor.apply();
                        }
                    }
                };

                try {
                     mHelper.queryInventoryAsync(true, skus, null, mReceivedInventoryListener);
                } catch (IabHelper.IabAsyncInProgressException e) {

                }
            }
        });

        startActivity(new Intent(MainPage.this, Changelog.class));

I am not aware what is wrong with this code. Thank you in advance for the help and Happy New Year! :)

Answer 1

You must call IabHelper.queryInventoryAsync() in order for a QueryInventoryFinishedListener to do anything useful. Just add a call to that function immediately prior to your startActivity() call. (This is assuming you've already called IabHelper.startSetup() and all that good stuff first.)

You cannot refer to a local variable prior to its declaration. The reason you got a "mReceivedInventoryListener cannot be resolved" error is because the answer referenced in your example swapped the two lines in a confusing way.

Obligatory mention: IabHelper is apparently no longer supported by Google; you're supposed to use the billing client library instead.