在活动之间传递对象的arraylist

Question

我试图在两个活动之间传递一个对象的arraylist,但我的应用程序在第二个活动时崩溃.有人可以帮我解决这个问题......

这是我第一次活动的代码:

Intent i = new Intent();
Bundle b = new Bundle();
b.putParcelableArrayList("songs",(ArrayList<? extends Parcelable>) albumsArray.get(position).getSongs());
Log.v("--", "OK");
i.putExtras(b);
i.setClass(LatestAlbums.this, AlbumDetails.class);
startActivity(i);

和第二个活动的代码:

songs=new ArrayList<Songs>();
Bundle b = this.getIntent().getExtras();
if(b!=null)
    songs = b.getParcelable("songs");
Log.v("--", songs.size()+"");

我的logcat输出:

04-03 16:37:03.513: E/AndroidRuntime(6576): FATAL EXCEPTION: main
04-03 16:37:03.513: E/AndroidRuntime(6576): java.lang.RuntimeException: Parcel: unable to marshal value com.musicapp.objects.Songs@419489e8
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Parcel.writeValue(Parcel.java:1137)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Parcel.writeList(Parcel.java:524)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Parcel.writeValue(Parcel.java:1097)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Parcel.writeMapInternal(Parcel.java:493)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Bundle.writeToParcel(Bundle.java:1612)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Parcel.writeBundle(Parcel.java:507)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.content.Intent.writeToParcel(Intent.java:6147)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.ActivityManagerProxy.startActivity(ActivityManagerNative.java:1613)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.Instrumentation.execStartActivity(Instrumentation.java:1379)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.Activity.startActivityFromChild(Activity.java:3458)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.Activity.startActivityForResult(Activity.java:3210)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:817)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.Activity.startActivity(Activity.java:3297)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at com.outsourcefarm.musicagratis.activities.LatestAlbums$4$1.onItemClick(LatestAlbums.java:232)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.widget.AdapterView.performItemClick(AdapterView.java:292)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.widget.AbsListView.performItemClick(AbsListView.java:1058)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:2514)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.widget.AbsListView$1.run(AbsListView.java:3168)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Handler.handleCallback(Handler.java:605)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Handler.dispatchMessage(Handler.java:92)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.os.Looper.loop(Looper.java:137)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at android.app.ActivityThread.main(ActivityThread.java:4440)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at java.lang.reflect.Method.invokeNative(Native Method)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at java.lang.reflect.Method.invoke(Method.java:511)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:787)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:554)
04-03 16:37:03.513: E/AndroidRuntime(6576):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

你试试下面的

intent.putParcelableArrayListExtra("key", ArrayList<T extends Parcelable> list);
startActivity(intent);

检索它

getIntent().getParcelableArrayListExtra("key");

将用户定义对象的arraylist传递给Intent android.检查Sajmon的答案

根据Sajmon的评论,Song上课必须implement Parcelable

Answer 2

你应该让你的Song类实现Parcelable.

Answer 3

Intent intent=new Intent(ActivityFrom.this,ActivityTo.class);
intent.putExtra("StringKey",arrayList);
startActivity(intent);

并检索

ArrayList<String> myList = (ArrayList<String>) getIntent().getSerializableExtra("StringKey");