Question

我有这个源代码，我试图让它工作，我从在线教程。它的问题是我得到一个错误： “不幸的是，MainScreen已经停止了”;

现在，我在网上寻找可能的解决方案并发现它可能在AndroidManifest.xml中，并且我将ap的名称更改为com.example.androidhive并且没有机会了......

以下是代码：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.androidhive"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="8" />

    <application
        android:configChanges="keyboardHidden|orientation"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >


        <activity
            android:name=".MainScreenActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <!-- All Product Activity -->
        <activity
            android:name=".AllProductsActivity"
            android:label="All Products" >
        </activity>

        <!-- Add Product Activity -->
        <activity
            android:name=".NewProductActivity"
            android:label="Add New Product" >
        </activity>

        <!-- Edit Product Activity -->
        <activity
            android:name=".EditProductActivity"
            android:label="Edit Product" >
        </activity>
    </application>

    <!--  Internet Permissions -->
    <uses-permission android:name="android.permission.INTERNET" />

</manifest>

谢谢..

日志

05-06 08:29:03.940: E/AndroidRuntime(757): FATAL EXCEPTION: AsyncTask #1
05-06 08:29:03.940: E/AndroidRuntime(757): java.lang.RuntimeException: An error occured while executing doInBackground()
05-06 08:29:03.940: E/AndroidRuntime(757):  at android.os.AsyncTask$3.done(AsyncTask.java:299)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.FutureTask.run(FutureTask.java:137)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.lang.Thread.run(Thread.java:856)
05-06 08:29:03.940: E/AndroidRuntime(757): Caused by: java.lang.NullPointerException
05-06 08:29:03.940: E/AndroidRuntime(757):  at com.example.androidhive.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:130)
05-06 08:29:03.940: E/AndroidRuntime(757):  at com.example.androidhive.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:1)
05-06 08:29:03.940: E/AndroidRuntime(757):  at android.os.AsyncTask$2.call(AsyncTask.java:287)
05-06 08:29:03.940: E/AndroidRuntime(757):  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
05-06 08:29:03.940: E/AndroidRuntime(757):  ... 4 more

Answer 1

您的日志猫显示NullPointerException

05-06 08:29:03.940: E/AndroidRuntime(757): Caused by: java.lang.NullPointerException

它似乎在No： - AllProductsAct.java的130个asyncTask的doInBackground方法中。检查该行应该有一个尚未分配的变量。

05-06 08:29:03.940: E/AndroidRuntime(757):  at com.example.androidhive.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:130)

也发布你的代码。

不幸的是，应用程序已在Android应用程

1 个答案: