startActivity（）強制關閉我的應用程序

Question

無論我做什麼，我都無法啓動新的活動。 我重新下載了所有的Android SDK。 我重新下載Eclipse和再次安裝ADT插件

錯誤日誌

09-16 17:53:51.537: W/IInputConnectionWrapper(4661): getCursorCapsMode on inactive InputConnection 
09-16 17:53:51.998: D/AndroidRuntime(4661): Shutting down VM 
09-16 17:53:51.998: W/dalvikvm(4661): threadid=1: thread exiting with uncaught exception (group=0x41987300) 
09-16 17:53:52.022: E/AndroidRuntime(4661): FATAL EXCEPTION: main 
09-16 17:53:52.022: E/AndroidRuntime(4661): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.lays.decisong/com.lays.decisong.activities.GameActivity}: java.lang.NullPointerException 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread.access$600(ActivityThread.java:130) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.os.Handler.dispatchMessage(Handler.java:99) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.os.Looper.loop(Looper.java:137) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread.main(ActivityThread.java:4745) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at java.lang.reflect.Method.invokeNative(Native Method) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at java.lang.reflect.Method.invoke(Method.java:511) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at dalvik.system.NativeStart.main(Native Method) 
09-16 17:53:52.022: E/AndroidRuntime(4661): Caused by: java.lang.NullPointerException 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.content.ContextWrapper.getApplicationInfo(ContextWrapper.java:132) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.view.ContextThemeWrapper.getTheme(ContextThemeWrapper.java:65) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.AlertDialog.resolveDialogTheme(AlertDialog.java:142) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.AlertDialog.<init>(AlertDialog.java:98) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ProgressDialog.<init>(ProgressDialog.java:77) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ProgressDialog.show(ProgressDialog.java:110) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ProgressDialog.show(ProgressDialog.java:99) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.lays.decisong.activities.GameActivity$3.<init>(GameActivity.java:401) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.lays.decisong.activities.GameActivity.<init>(GameActivity.java:398) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at java.lang.Class.newInstanceImpl(Native Method) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at java.lang.Class.newInstance(Class.java:1319) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.Instrumentation.newActivity(Instrumentation.java:1053) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974) 

公鑰DecisongApplication.java

public static final String PLAYERS_KEY = "com.lays.decisong.activities.Players"; 

按鈕處理程序中InputActivity.java

應用力關閉當startActivity（）被調用時

public void startGame(View v) { 
    // check if there's more than one player 
    if (mPlayers.size() < 2) { 
     Log.i(TAG, "Only 1 player"); 
     Toast.makeText(mContext, "At least 2 players needed to start game", 
       Toast.LENGTH_SHORT).show(); 
     return; 
    } 

    Intent intent = new Intent(this.getApplicationContext(), GameActivity.class); 
    intent.putStringArrayListExtra(DecisongApplication.PLAYERS_KEY, mPlayers); 
    startActivity(intent); 
    overridePendingTransition(R.anim.slide_up_incoming, R.anim.slide_up_outgoing); 
} 

在com.lays.decisong.activities GameActivity.java的的Manifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="com.lays.decisong" 
android:versionCode="1" 
android:versionName="1.0" > 

<uses-sdk 
    android:minSdkVersion="10" 
    android:targetSdkVersion="16" /> 

<supports-screens 
    android:anyDensity="true" 
    android:largeScreens="false" 
    android:normalScreens="true" 
    android:smallScreens="false" 
    android:xlargeScreens="false" /> 

<uses-permission android:name="android.permission.INTERNET" /> 
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> 

<application 
    android:name="com.lays.decisong.DecisongApplication" 
    android:icon="@drawable/ic_launcher" 
    android:label="@string/app_name" 
    android:screenOrientation="portrait" 
    android:theme="@android:style/Theme.NoTitleBar" > 
    <activity android:name=".activities.MainActivity" > 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 

      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
    <activity 
     android:name=".activities.InstructionsActivity" 
     android:noHistory="true" /> 
    <activity 
     android:name=".activities.InputActivity" 
     android:noHistory="true" /> 
    <activity 
     android:name=".activities.SettingsActivity" 
     android:noHistory="true" /> 
    <activity 
     android:name=".activities.GameActivity" 
     android:noHistory="true" /> 
</application> 

</manifest> 

的onCreate從未接到電話

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_game); 

    // init rdio variables 
    mTrackQueue = new LinkedList<Track>(); 
    if (mRdio == null) { 
     mRdio = new Rdio(DecisongApplication.RDIO_API_KEY, 
       DecisongApplication.RDIO_SECRET_KEY, null, null, this, this); 
    } 

    // init quiz variables 
    mListView = getListView(); 
    mAllAlbums = new HashMap<String, Album>(); 
    mChosenTracks = new ArrayList<Track>(); 
    mAdapter = new TracksAdapter(this, mChosenTracks); 
    setListAdapter(mAdapter); 

    // init player variables 
    mCurrentRoundView = (TextView) findViewById(R.id.current_round); 
    mCurrentRound = INITIAL_ROUND; 
    mCurrentPlayerView = (TextView) findViewById(R.id.current_player); 
    mCurrentPlayer = INITIAL_PLAYER; 
    mPlayers = new ArrayList<Player>(); 
    if (getIntent().hasExtra(DecisongApplication.PLAYERS_KEY)) { 
     ArrayList<String> players = getIntent().getStringArrayListExtra(DecisongApplication.PLAYERS_KEY); 
     for (String p : players) { 
      mPlayers.add(Player.create(p)); 
     } 
    } 

    // setup game conditions 
    Collections.shuffle(mPlayers); 
    mCurrentPlayerView.setText(mPlayers.get(mCurrentPlayer).name); 
} 

Answer 1

09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.lays.decisong.activities.GameActivity$3.<init>(GameActivity.java:401) 
09-16 17:53:52.022: E/AndroidRuntime(4661):  at com.lays.decisong.activities.GameActivity.<init>(GameActivity.java:398) 

貌似你試圖做一些在GameActivity的構造函數中設置，或者在活動的Context完全初始化之前初始化一些字段。你應該在onCreate()真的做所有的設置;不要使用構造函數，並且不要依賴Context可用，直到輸入onCreate()。