Question

I was learning about In-App purchase task in blackberry using Payment SDk version 1.8.
Currently I am using the below code:

package com.purchasedemo;

///import net.rimlib.blackberry.api.payment.*;
import net.rimlib.blackberry.api.paymentsdk.PaymentEngine;
import net.rimlib.blackberry.api.paymentsdk.PaymentException;
import net.rimlib.blackberry.api.paymentsdk.Purchase;
import net.rimlib.blackberry.api.paymentsdk.PurchaseArgumentsBuilder;
import net.rimlib.blackberry.api.paymentsdk.PurchaseResult;
import net.rimlib.blackberry.api.paymentsdk.purchaseHistory.PurchaseHistory;
import net.rimlib.blackberry.api.paymentsdk.purchaseHistory.PurchaseHistoryListingListener;
import net.rim.device.api.ui.*;
import net.rim.device.api.ui.component.*;
import net.rim.device.api.ui.container.*;

public class PurchaseDemo extends UiApplication
{
    public static void main(String[] args) 
    {
        PurchaseDemo theApp = new PurchaseDemo();
        theApp.enterEventDispatcher();  
    }
    public PurchaseDemo() 
    {   
        pushScreen(new PurchaseDemoScreen());
    }


      private static class PurchaseDemoScreen extends MainScreen implements FieldChangeListener {
            private BasicEditField parentSku;
            private ButtonField buyButton;
            private ButtonField displayButton;
            private BasicEditField digitalGoodName;
            private BasicEditField digitalGoodSku;
            private PurchaseHistoryListingListener purchaseHistoryListener;
            private PaymentEngine **engine** = PaymentEngine.getInstance();

            public PurchaseDemoScreen() {
                setTitle( "Payment Service SDK Demo" );

                if( **engine** != null ) {
                    parentSku = new BasicEditField( "Parent SKU: ", "abc123" );
                    add( parentSku );
                    digitalGoodName = new BasicEditField( "Digital Good Name: ", "Sample Good" );
                    add( digitalGoodName );
                    digitalGoodSku = new BasicEditField( "Digital Good SKU: ", "abc123" );
                    add( digitalGoodSku );
                    HorizontalFieldManager hfm = new HorizontalFieldManager();
                    add( hfm );
                    buyButton = new ButtonField( "Buy" );
                    buyButton.setChangeListener( this );
                    hfm.add( buyButton );
                    displayButton = new ButtonField( "Display Purchases" );
                    displayButton.setChangeListener( this );
                    hfm.add( displayButton );
                } else {
                    RichTextField errorMessage = new RichTextField( "Sorry, in-app purchases are unavailable" );
                    add( errorMessage );
                }
            }

            public void fieldChanged( Field field, int context ) {
                if( field == buyButton ) {
                    String name = digitalGoodName.getText();
                    String sku = digitalGoodSku.getText();
                    PurchaseArgumentsBuilder arguments = new PurchaseArgumentsBuilder().withDigitalGoodSku( sku )
                            .withDigitalGoodName( name ).withMetadata( name ).withPurchasingAppName( "Payment Service SDK Demo" );
                    try {
                        PurchaseResult purchase = engine.purchase( arguments.build() );
                        Dialog.inform( "Purchase of " + purchase.getMetadata() + " is successful." );
                    } catch( IllegalArgumentException e ) {
                        Dialog.inform( e.getMessage() );
                    } catch( PaymentException e ) {
                        Dialog.inform( e.getMessage() );
                    }
                } else if( field == displayButton ) {
                    purchaseHistoryListener = new PurchaseHistoryListingListener() {

                        public void error( String message, int errorCode ) {
                            Dialog.inform( message );
                        }

                        public void success( Purchase[] purchases ) {
                            if( purchases.length != 0 ) {
                                if( getFieldCount() > 3 ) {
                                    deleteRange( 3, ( getFieldCount() - 3 ) );
                                }
                                for( int i = 0; i < purchases.length; i++ ) {
                                    RichTextField purchaseRecord = new RichTextField( "Name: " + purchases[ i ].getMetadata()
                                            + " SKU: " + purchases[ i ].getDigitalGoodSku() );
                                    add( purchaseRecord );
                                }
                            } else {
                                Dialog.inform( "No existing purchases" );
                            }
                        }
                    };

                    PurchaseHistory.get(purchaseHistoryListener);
                }
            }
        }
}

By using this code, I was just trying to learn how this process actually work.
But the PROBLEM IS, i am getting null in the engine object of PaymentEngine.
Please let me know how can i solve this problem.
And also what are the actual requirements of this service. Currently I am working on 5.0 OS and in device 6.0 OS

Answer 1

The first thing you want to do, before making the call to PaymentEngine.getInstance() you should first be calling PaymentEngine.isAppWorldInstalledAndAtCorrectVersion(). This call checks to see what version of App World is installed to the device and if it needs to be upgraded. The Payment SDK requires a minimum version of App World that changes with SDK versions, so the above call will help keep you safe. If this throws an exception you can call PaymentEngine.upDateAppWorld() to initiate the update.

If the version of App World is at the correct version then please include some information on the version of App World on the device and the exact device models and software versions used to repro the issue.