将字符串数组传递给另一个活动

Question

我从我的分析对象中获取数据，并且数据显示在各个视图中。 但是我的应用程序崩溃每当我点击showMenu按钮（的onClick方法是showMenu） 这是我的代码

public class SingleRestraunt extends ActionBarActivity { 
    private GoogleMap map; 
    TextView resteName, resteCuisine, resteLocation, resteAddress, restePrice, 
      resteTimings, restePayment, resteRating, resteWebsite; 
    String restName, obj, restCuisine, restLocation, restAddress, restPrice, 
      restTimings, restPayment, restRating, restWebsite; 
    String[] menu = null; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_single_restraunt); 
     resteName = (TextView) findViewById(R.id.restrauntName); 
     resteCuisine = (TextView) findViewById(R.id.restrauntCuisine); 
     resteLocation = (TextView) findViewById(R.id.restrauntLocation); 
     resteAddress = (TextView) findViewById(R.id.restrauntAddress); 
     restePrice = (TextView) findViewById(R.id.restrauntPrice); 
     resteTimings = (TextView) findViewById(R.id.restrauntTimings); 
     restePayment = (TextView) findViewById(R.id.restrauntPayment); 
     resteRating = (TextView) findViewById(R.id.restrauntRating); 
     resteWebsite = (TextView) findViewById(R.id.restrauntWebsite); 

     Intent i = getIntent(); 
     obj = i.getStringExtra("restId"); 
     getDetails(obj); 

    } 

    private void getDetails(String obj) { 

     ParseQuery<ParseObject> query = ParseQuery.getQuery("resdb"); 
     query.getInBackground(obj, new GetCallback<ParseObject>() { 

      @Override 
      public void done(ParseObject object, ParseException e) { 
       if (e == null) { 
        restName = object.getString("name"); 
        restCuisine = object.getString("cuisine"); 
        restLocation = object.getString("locality"); 
        restAddress = object.getString("address"); 
        restPrice = object.getString("price"); 
        restTimings = object.getString("timings"); 
        restPayment = object.getString("accepted"); 
        restRating = object.getString("ratings"); 
        restWebsite = object.getString("URL"); 
        JSONArray test = object.getJSONArray("menu"); 
        for (int i = 0; i < test.length(); i++) { 
         try { 
          String menu1 = (String) test.get(i); 
          if (menu1 == null) 
           menu[i] = menu1; 
         } catch (JSONException e1) { 
          e1.printStackTrace(); 
         } 
        } 
        addData(); 

       } else { 
        e.printStackTrace(); 
       } 
      } 
     }); 

    } 

    public void addData() { 
     resteName.setText(restName); 
     resteCuisine.setText(restCuisine); 
     resteLocation.setText(restLocation); 
     resteAddress.setText(restAddress); 
     restePrice.setText(restPrice); 
     resteTimings.setText(restTimings); 
     restePayment.setText(restPayment); 
     resteRating.setText(restRating); 
     resteWebsite.setText(restWebsite); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.single_restraunt, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 
     int id = item.getItemId(); 
     if (id == R.id.action_settings) { 
      return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 

    public void Review(View v) { 
     Intent i = new Intent(SingleRestraunt.this, ReviewPage.class); 
     i.putExtra("RestName", restName); 
     startActivity(i); 
    } 

    public void Offer(View v) { 
     Intent i = new Intent(SingleRestraunt.this, OfferPage.class); 
     i.putExtra("RestName", restName); 
     startActivity(i); 
    } 

    public void showMenu(View v) { 

     Bundle b = new Bundle(); 
     b.putStringArray("menuList", menu); 
     Intent i = new Intent(SingleRestraunt.this, MenuActivity.class); 
     i.putExtras(b); 
     startActivity(i); 
    } 

    public void Share(View v) { 
     Intent sharingIntent = new Intent(android.content.Intent.ACTION_SEND); 
     sharingIntent.setType("text/plain"); 
     String shareBody = ("Hey! I visited " 
       + restName 
       + " recommended to me by the Gastronoma App! Visit their site here " + restWebsite); 
     sharingIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, 
       "Subject Here"); 
     sharingIntent.putExtra(android.content.Intent.EXTRA_TEXT, shareBody); 
     startActivity(Intent.createChooser(sharingIntent, "Share via")); 
    } 

} 

的应用程序似乎当我点击showMenu按钮，仅崩溃。直到这一点的应用程序正常工作。所有其他按钮也完美地完成了他们预期的任务。当应用程序崩溃是

09-02 09:54:22.307: E/AndroidRuntime(3278): Process: com.example.gastronomaapp, PID: 3278 
09-02 09:54:22.307: E/AndroidRuntime(3278): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.gastronomaapp/com.example.gastronomaapp.MenuActivity}: java.lang.NullPointerException 

公开赛的要求我加入这两个MenuActivity代码和清单文件

public class MenuActivity extends Activity { 
    WebView web = (WebView) findViewById(R.id.webView1); 
    TextView next = (TextView) findViewById(R.id.next); 
    TextView prev = (TextView) findViewById(R.id.prev); 
    int i = 0; 

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

     Bundle b = this.getIntent().getExtras(); 
     String[] array = b.getStringArray("menuList"); 
     getMenu(array); 
    } 

    public void getMenu(final String[] array) { 
     String menu = array[i]; 
     web.loadUrl(menu); 
     visibility(i, array); 
     next.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       i++; 
       String menu = array[i]; 
       web.loadUrl(menu); 
       visibility(i, array); 
      } 

     }); 
     prev.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       i--; 
       String menu = array[i]; 
       web.loadUrl(menu); 
       visibility(i, array); 
      } 

     }); 
    } 

    private void visibility(int i, String[] array) { 
     if (i == 0) 
      prev.setVisibility(View.GONE); 
     if (i == array.length - 1) 
      next.setVisibility(View.GONE); 
    } 

而且清单

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

    <permission 
     android:name="com.example.gastronomaapp.permission.MAPS_RECEIVE" 
     android:protectionLevel="signature" /> 

    <uses-sdk 
     android:minSdkVersion="14" 
     android:targetSdkVersion="21" /> 

    <uses-permission android:name="com.example.gastronomaapp.permission.MAPS_RECEIVE" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> 
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> 
    <uses-permission android:name="android.permission.INTERNET" /> 
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 

    <uses-feature 
     android:glEsVersion="0x00020000" 
     android:required="true" /> 

    <!-- 
     <application> 
     <meta-data 
      android:name="com.google.android.gms.version" 
      android:value="@integer/google_play_services_version" /> 
    </application> 








    --> 
    <application 
     android:allowBackup="true" 
     android:icon="@drawable/ic_launcher" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme" > 
     <activity 
      android:name=".MainActivity" 
      android:label="@string/app_name" > 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 
     <activity 
      android:name=".ResterauntList" 
      android:label="@string/title_activity_resteraunt_list" > 
     </activity> 
     <activity 
      android:name=".Map" 
      android:label="@string/title_activity_map" > 
     </activity> 
     <activity 
      android:name=".Button1List" 
      android:label="@string/title_activity_button1_list" > 
     </activity> 
     <activity 
      android:name=".SingleRestraunt" 
      android:label="@string/title_activity_single_restraunt" > 
     </activity> 

     <meta-data 
      android:name="com.google.android.maps.v2.API_KEY" 
      android:value="AIzaSyAaC-32WynuOO6stpRaK6LSxRMwCuvgdE4" /> 
     <meta-data 
      android:name="com.google.android.gms.version" 
      android:value="@integer/google_play_services_version" /> 

     <activity 
      android:name=".ReviewPage" 
      android:label="@string/title_activity_review_page" > 
     </activity> 
     <activity 
      android:name=".OfferPage" 
      android:label="@string/title_activity_offer_page" > 
     </activity> 
     <activity 
      android:name=".ImageMenu" 
      android:label="@string/title_activity_image_menu" > 
     </activity> 
     <activity 
      android:name=".MenuActivity" 
      android:label="@string/title_activity_menu" > 
     </activity> 
    </application> 

</manifest> 

Answer 1

任何suggestions.EDIT所示的错误您必须执行以下操作：

Intent i = new Intent("Activity") 
i.putExtra(key, ArrayName) 

Intent i = getIntent(); 
String[] array = i.getExtras().getString(keyname); 

就是这样。

Answer 2

NPE很可能是由于以下原因造成的：

1. menu数组声明但尚未初始化。它应该是：

   String menu [] = new String [SIZE_OF_MY_MENU_ARRAY]; 
   

2. 确保menu阵列是NOT NULL。

3. 在你的代码，

   if (menu1 == null) 
       menu[i] = menu1; // <--- Null value is assigned to your array. Avoid that 
   

---

原来的答案

如果你正在传输比如从字符串数组，ActivityA.java到ActivityB.java

在ActivityA.java，

String [] myStringArray = // Declare Here... 

Bundle b=new Bundle(); 
b.putStringArray("MY_KEY", myStringArray); 
Intent i=new Intent(context, ActivityA); 
i.putExtras(b); 

要读取的字符串数组中ActivityB.java

Bundle b=this.getIntent().getExtras(); 
String[] myStringArray =b.getStringArray("MY_KEY"); 

您也使用了类似的语法在你的问题。