راهنمایی در مورد پرداخت درون برنامه

[NeoFighT]

سلام دوستان
من طبق مستندات خود بازار این کد رو نوشتم و نمیدونم چرا اجرا نمیده(خطای Null Pointer Exception میده.)
اگه امکانش هست راهنمایی کنید. ممنون

package com.example.testiap;


import com.example.testiap.util.IabHelper;
import com.example.testiap.util.IabResult;
import com.example.testiap.util.Inventory;
import com.example.testiap.util.Purchase;


import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;


public class MainActivity extends Activity {
Button btn;
TextView tv;

// Debug tag, for logging
static final String TAG = "MainActivity";


// SKUs for our products: the premium upgrade (non-consumable)
static final String SKU_PREMIUM = "premium_user";


// Does the user have the premium upgrade?
boolean mIsPremium = false;


// (arbitrary) request code for the purchase flow
static final int RC_REQUEST = 122;


// The helper object
IabHelper mHelper;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

btn = (Button) findViewById(R.id.button1);
tv = (TextView) findViewById(R.id.textView1);

btn.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
mHelper.launchPurchaseFlow(MainActivity.this, SKU_PREMIUM, RC_REQUEST, mPurchaseFinishedListener, "payload-string");
}
});

String base64EncodedPublicKey = "MIHNMA0GCSqGSIb3DQEBAQUAA4G7ADCBtwKBrwDVKQPrTWa2xv gcMtj2Chr76AaLe/EkQ/yxNcbKin63x7ncnoF8F6XKgu8QS5SgNZhWKvF7thQGquzgp8sp I620ayul/V4loK887layrRgGRBMUVNUIAqL9sRv14Zju6gfL76E+FZYMwGV gQ0rsFlYRwnb13/iaMHS0UjeVZqMQ0rgLir80yvtYvuhy2qh3pU4MAisEUNOhJ9wl C0Ix993vJd+GtkjRTINF1fwL9vUCAwEAAQ==";
// You can find it in your Bazaar console, in the Dealers section.
// It is recommended to add more security than just pasting it in your source code;
mHelper = new IabHelper(this, base64EncodedPublicKey);


Log.d(TAG, "Starting setup.");
mHelper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
public void onIabSetupFinished(IabResult result) {
Log.d(TAG, "Setup finished.");


if (!result.isSuccess()) {
// Oh noes, there was a problem.
Log.d(TAG, "Problem setting up In-app Billing: " + result);
}
// Hooray, IAB is fully set up!
mHelper.queryInventoryAsync(mGotInventoryListener) ;
}
});
}

IabHelper.QueryInventoryFinishedListener mGotInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
Log.d(TAG, "Query inventory finished.");
if (result.isFailure()) {
Log.d(TAG, "Failed to query inventory: " + result);
return;
}
else {
Log.d(TAG, "Query inventory was successful.");
// does the user have the premium upgrade?
mIsPremium = inventory.hasPurchase(SKU_PREMIUM);


// update UI accordingly


Log.d(TAG, "User is " + (mIsPremium ? "PREMIUM" : "NOT PREMIUM"));
}


Log.d(TAG, "Initial inventory query finished; enabling main UI.");
}
};


IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
public void onIabPurchaseFinished(IabResult result, Purchase purchase) {
if (result.isFailure()) {
Log.d(TAG, "Error purchasing: " + result);
return;
}
else if (purchase.getSku().equals(SKU_PREMIUM)) {
// give user access to premium content and update the UI
}
}
};


@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);


Log.d(TAG, "onActivityResult(" + requestCode + "," + resultCode + "," + data);


// Pass on the activity result to the helper for handling
if (!mHelper.handleActivityResult(requestCode, resultCode, data)) {
super.onActivityResult(requestCode, resultCode, data);
} else {
Log.d(TAG, "onActivityResult handled by IABUtil.");
}
}


@Override
public void onDestroy() {
super.onDestroy();
if (mHelper != null) mHelper.dispose();
mHelper = null;
}
}