Application of how data is transmitted and shared between Android activity

1. Message-based communication mechanism Intent---bundle, extra

Data types are limited, such as encountering non-serializable data bitmap,inputstream, or linkedlist linked lists, and so on.

2 static data, public static member variable;

3. External storage-based transmissions , File/preference/sqlite

If you want content Provider for third-party apps

4. IPC-Based communication mechanisms

The transfer between context and service, such as communication between activity and service, defines the Aidl interface file.

5. Based on application Context

This method can be used for data types such as non-serializable data bitmap,inputstream, or linkedlist linked lists, and so on.

There is currently a project that needs to use the data transfer of activity, initializing a arraylist

Java implementations:

1  Public classContactappextendsApplication {2     3     Privatearraylist4             NewArraylist();5     6      Public voidSetcontactitem (arraylistItem) {7          This. Contactmap =item;8     }9     Ten      PublicArraylistGetcontactitem () { One         returnContactmap; A     } -}

To configure in Androidmanifest.xml:

1 <application2     android:name= ". Model. Contactapp "3     android:icon=" @drawable/icon "4     android:label=" @string/app_name " >5     ... 6 </application>

To access in other activity:

Setting Data:

1 Contactapp app = (Contactapp) getapplication (); 2 App.setcontactitem (ContactItem);

Get Data:

1 Contactapp app = (Contactapp) getapplication (); 2 app.getcontactitem ();