我正在尝试对我的应用程序实施应用内计费。
我正在阅读 developer.android.com 上的指南,查看他们的示例应用程序。
我开始编写检查是否支持应用内计费的基本方法,但是当我尝试调用 sendBillingRequest 时,我收到以下错误:
05-17 14:23:30.479: W/System.err(15332): java.lang.NullPointerException
05-17 14:23:30.489: W/System.err(15332): at resistorcalc.main.billing.BillingService.checkBilling(BillingService.java:63)
05-17 14:23:30.489: W/System.err(15332): at resistorcalc.main.SupportusActivity.onCreate(SupportusActivity.java:24)
05-17 14:23:30.499: W/System.err(15332): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-17 14:23:30.509: W/System.err(15332): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
05-17 14:23:30.509: W/System.err(15332): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
05-17 14:23:30.519: W/System.err(15332): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
05-17 14:23:30.529: W/System.err(15332): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
05-17 14:23:30.539: W/System.err(15332): at android.os.Handler.dispatchMessage(Handler.java:99)
05-17 14:23:30.539: W/System.err(15332): at android.os.Looper.loop(Looper.java:130)
05-17 14:23:30.549: W/System.err(15332): at android.app.ActivityThread.main(ActivityThread.java:3687)
05-17 14:23:30.549: W/System.err(15332): at java.lang.reflect.Method.invokeNative(Native Method)
05-17 14:23:30.549: W/System.err(15332): at java.lang.reflect.Method.invoke(Method.java:507)
05-17 14:23:30.549: W/System.err(15332): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
05-17 14:23:30.559: W/System.err(15332): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
05-17 14:23:30.559: W/System.err(15332): at dalvik.system.NativeStart.main(Native Method)
billingService 类是:
package resistorcalc.main.billing;
import android.app.Service;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.os.RemoteException;
import android.util.Log;
import com.android.vending.billing.IMarketBillingService;
public class BillingService extends Service implements ServiceConnection {
private static final String TAG = "BillingService";
private IMarketBillingService mService;
public BillingService(){
super();
}
@Override
public void onCreate() {
super.onCreate();
try {
Log.i(TAG, "Service starting with onCreate");
boolean bindResult = bindService(new Intent("com.android.vending.billing.MarketBillingService.BIND"), this, Context.BIND_AUTO_CREATE);
if(bindResult){
Log.i(TAG,"Market Billing Service Successfully Bound");
} else {
Log.e(TAG,"Market Billing Service could not be bound.");
}
} catch (SecurityException e){
Log.e(TAG,"Market Billing Service could not be bound. SecurityException: "+e);
}
}
public void setContext(Context context) {
attachBaseContext(context);
}
/**
* The Android system calls this when we are connected to the MarketBillingService.
*/
public void onServiceConnected(ComponentName name, IBinder service) {
Log.i(TAG, "MarketBillingService connected.");
mService = IMarketBillingService.Stub.asInterface(service);
}
protected Bundle makeRequestBundle(String method) {
Bundle request = new Bundle();
request.putString(BillingConst.BILLING_REQUEST_METHOD, method);
request.putInt(BillingConst.BILLING_REQUEST_API_VERSION, 1);
request.putString(BillingConst.BILLING_PACKAGE_NAME, getPackageName());
return request;
}
public boolean checkBilling(){
try {
Bundle request = makeRequestBundle("CHECK_BILLING_SUPPORTED");
Bundle response = mService.sendBillingRequest(request);
int code = response.getInt("RESPONSE_CODE");
if(code==0){
return true;
} else {
return false;
}
} catch (Exception e) {
e.printStackTrace();
System.err.print(e.getMessage());
return false;
}
}
public void onServiceDisconnected(ComponentName arg0) {
// TODO Auto-generated method stub
}
@Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
}
该行发生异常:
捆绑响应 = mService.sendBillingRequest(request);
发生这种情况是因为 mService 变量为空。mService 变量在该方法上初始化:
public void onServiceConnected(ComponentName name, IBinder service) {
Log.i(TAG, "MarketBillingService connected.");
mService = IMarketBillingService.Stub.asInterface(service);
}
(如该指南中所述:http: //developer.android.com/guide/market/billing/billing_integrate.html#billing-service)问题是永远不会调用 onServiceConnected 。
启动服务的活动:
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.supportus);
mBillingService = new BillingService();
mBillingService.setContext(this);
Intent intent = new Intent();
intent.setClass(this, BillingService.class);
startService(intent);
if(mBillingService.checkBilling()){
Toast.makeText(this, "TRUE", Toast.LENGTH_SHORT);
} else {
Toast.makeText(this, "FALSE", Toast.LENGTH_SHORT);
}
}
我无法理解问题所在。为什么不调用 onCreate 和 onServiceConnected 方法?查看服务生命周期,应使用 startService 调用 BillingService onCreate 方法。我哪里错了