我想在Android的传递活动之间的数组列表。这份名单包含字符串。我读过很多关于Parcelable。我需要创建一个Parcelable通过一个字符串数组列表？截至目前，我使用putStringArrayListExtra（）和getSringArrayListExtra（）通过意图传递名单。

下面是我的一些code。

 意图负荷=新的意向书（getApplicationContext（），HelloTabWidget.class）;
        load.putStringArrayListExtra（专辑，专辑）;
        load.putStringArrayListExtra（歌，歌曲）;
        load.putStringArrayListExtra（艺术家，艺术家）;
        load.putStringArrayListExtra（文件名，文件名）;
 

这是我为它获取数组列表中的acticity onCreate方法。

 公共无效的onCreate（包savedInstanceState）{
    super.onCreate（savedInstanceState）;
    的setContentView（R.layout.songlist）;

    捆绑额外= getIntent（）getExtras（）。
    isArtists = extras.getBoolean（艺术家）;
    isAlbums = extras.getBoolean（相册）;
    isSongs = extras.getBoolean（诗经）;

        意图的get = getIntent（）;
        歌曲= get.getStringArrayListExtra（诗经）;
        艺术家= get.getStringArrayListExtra（艺术家）;
        专辑= get.getStringArrayListExtra（相册）;
        文件名= get.getStringArrayListExtra（文件名）;



    如果（isArtists ==真）
        updateArtistsList（）;
    否则，如果（isAlbums ==真）
        updateAlbumsList（）;
    否则，如果（isSongs ==真）
        updateSongList（）;
}
 

以检索列表中的类应该创建从列表中的数据列表视图。每当我运行codeI得到NullPointerException异常努力使列表时。我知道我的ListView code的作品，所以我已经缩小问题到传递数组列表中的意图。

在此先感谢。

编辑： 下面是从logcat的前几行。

  3月12号至28号：03：42.313：E / AndroidRuntime（873）：致命异常：主要
三月12日至28日：03：42.313：E / AndroidRuntime（873）：java.lang.RuntimeException的：无法启动的活动ComponentInfo {com.adam.mediaplayer / com.adam.mediaplayer.HelloTabWidget}：java.lang.RuntimeException的：无法启动活动ComponentInfo {com.adam.mediaplayer / com.adam.mediaplayer.MakeListActivity}：显示java.lang.NullPointerException
 

解决方案

这取决于ArrayList的类型

putIntegerArrayListExtra（字符串名称，ArrayList的＆LT;整数GT;值）

putParcelableArrayListExtra（字符串名称，ArrayList的＆LT ;?延伸Parcelable＆GT;值）

putStringArrayListExtra（字符串名称，ArrayList的＆LT;字符串＆GT;值）

putCharSequenceArrayListExtra（字符串名称，ArrayList的＆LT; CharSequence的＆GT;值）

然后就可以通过更换从你读下一个活动把与 GET 以关键字为参数，如

  myIntent.getStringArrayListExtra（arrayListName）;
 

I'm trying to pass array lists between activities in Android. The lists contains strings. I've read a lot about Parcelable. Would I need to create a Parcelable to pass a String array list? As of now I am using putStringArrayListExtra() and getSringArrayListExtra() to pass the lists through intents.

Here is some of my code.

Intent load = new Intent(getApplicationContext(), HelloTabWidget.class);
        load.putStringArrayListExtra("albums", albums);  
        load.putStringArrayListExtra("songs", songs);  
        load.putStringArrayListExtra("artists", artists); 
        load.putStringArrayListExtra("fileName", fileName);  

This is my onCreate method for the acticity which obtains the array list.

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.songlist); 

    Bundle extras = getIntent().getExtras();
    isArtists = extras.getBoolean("artists");   
    isAlbums = extras.getBoolean("albums"); 
    isSongs = extras.getBoolean("songs");   

        Intent get = getIntent();  
        songs = get.getStringArrayListExtra("songs"); 
        artists = get.getStringArrayListExtra("artists");
        albums = get.getStringArrayListExtra("albums");
        fileName = get.getStringArrayListExtra("fileName"); 



    if(isArtists == true)       
        updateArtistsList(); 
    else if(isAlbums == true) 
        updateAlbumsList();  
    else if(isSongs == true) 
        updateSongList();    
}

The class which retrieves the list is supposed to create a listView from the data in the lists. Whenever I run the code i get nullPointerExceptions when trying to make the lists. I know that my listView code works, so I have narrowed down the problem to the intents which pass the array lists.

Thanks in advance.

EDIT: Here are the first few lines from the logcat.

12-28 03:03:42.313: E/AndroidRuntime(873): FATAL EXCEPTION: main
12-28 03:03:42.313: E/AndroidRuntime(873): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.adam.mediaplayer/com.adam.mediaplayer.HelloTabWidget}: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.adam.mediaplayer/com.adam.mediaplayer.MakeListActivity}: java.lang.NullPointerException

It depends on the type of arraylist

putIntegerArrayListExtra(String name, ArrayList<Integer> value)

putParcelableArrayListExtra(String name, ArrayList<? extends Parcelable> value)

putStringArrayListExtra(String name, ArrayList<String> value)

putCharSequenceArrayListExtra(String name, ArrayList<CharSequence> value)

Then you can read from you next activity by replacing put with get with key string as argument,eg

myIntent.getStringArrayListExtra("arrayListName");