Intent object Passing (parcelable passing objects and collections of objects)

next , we'll discuss how to use Parcelable to implement an object transfer between intent

I. Implementation of Object passing

First create the User.java implementation Parcelable interface:

package org.yayun.demo;import java.io.serializable;import android. R.integer;import Android.os.parcel;import Android.os.parcelable;public class User implements parcelable {private string Name;private int level;public string getName () {return name;} public void SetName (String name) {this.name = name;} public int Getlevel () {return level;} public void SetLevel (Int. level) {this.level = level;} Public User (String name, int. level) {this.name = Name;this.level = level;} Public User () {//constructor method}public int describecontents () {//overwrite method return 0;} public void Writetoparcel (Parcel Parcel, int flags) {//Overwrite method parcel.writestring (name);p arcel.writeint (level);} public static final parcelable.creator<user> Creator = new creator<user> () {//methods must be implemented public User Createfromparcel (Parcel source) {User user = new User (); user.name = Source.readstring (); user.level = Source.readint (); return user;} Public user[] NewArray (int size) {return new user[size];}}; 

Parcelable.creator must be implemented, otherwise it will be an error:

Here's a look at two activity

1.mainactivity.java

Package Org.yayun.demo;import Android.app.activity;import Android.content.intent;import android.os.Bundle;import Android.view.view;import Android.view.view.onclicklistener;import Android.widget.button;public class MainActivity Extends Activity {private Button button;public void OnCreate (Bundle savedinstancestate) {super.oncreate ( Savedinstancestate); Life cycle Method Super.setcontentview (R.layout.main); Sets the layout manager to use button = (Button) Findviewbyid (R.ID.BTN); Button.setonclicklistener (new Onclicklistener () {public void  OnClick (View v) {User user1 = new User ("Yayun", 7);//Instantiate object Intent Intent = new intent (); Intent.setclass (Mainactivity.this, Loginactivity.class); Bundle bundle = new Bundle (), bundle.putparcelable ("user", User1),//serialization Intent.putextras (Bundle),//Send data startactivity ( intent);//Start Intent}});}}

2.loginactivity.java:

Package Org.yayun.demo;import Android.app.activity;import Android.content.intent;import android.os.Bundle;import Android.widget.textview;public class Loginactivity extends Activity {private TextView TextView; User user;public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);// Life cycle Method Super.setcontentview (R.layout.login); Set the layout manager to use TextView = (TextView) Findviewbyid (r.id.text); Intent Intent = This.getintent (); user = (user) Intent.getparcelableextra ("user"); Textview.settext ("Username:" + user.getname () + "User Level" + string.valueof (User.getlevel () ));}}

3. Run the following example:

You can see and implement the same results as the Serialiable interface.

Second, the realization of object collection delivery

Here we only need to change two activity

1.mainactivity.java:

Package Org.yayun.demo;import Java.util.arraylist;import Java.util.list;import android.app.activity;import Android.content.intent;import Android.os.bundle;import Android.view.view;import Android.view.View.OnClickListener Import Android.widget.button;public class Mainactivity extends Activity {private button button; List<user> list=new arraylist<user> ();p ublic void OnCreate (Bundle savedinstancestate) {super.oncreate ( Savedinstancestate); Life cycle Method Super.setcontentview (R.layout.main); Sets the layout manager to use button = (Button) Findviewbyid (R.ID.BTN); Button.setonclicklistener (new Onclicklistener () {public void OnClick (View v) {User User1 = new User ("Yayun", 7);//Instantiate the object user User2=new user ("Feifei", 9); List.add (user1); List.add ( User2); Intent Intent = new Intent (); Intent.setclass (Mainactivity.this, Loginactivity.class);                  Bundle bundle = new Bundle (), Bundle.putparcelablearraylist ("list", (arraylist<user>) list);//serialization, to be aware of Intent.putextras (bundle);//Send Data startactivity (intent);// Start Intent}});}} 

2.loginactivity.java

Package Org.yayun.demo;import Java.util.list;import Android.app.activity;import android.content.intent;import Android.os.bundle;import Android.widget.textview;public class Loginactivity extends Activity {private TextView TextView; List<user> list; User user2;public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);// Life cycle Method Super.setcontentview (R.layout.login); Set the layout manager to use TextView = (TextView) Findviewbyid (r.id.text); Intent Intent = This.getintent (); list =  Intent.getparcelablearraylistextra ("list");//getparcelablearraylistextra method User2= (User) list.get (1); Textview.settext ("Username:" + user2.getname () + "User Level" + string.valueof (User2.getlevel ());}}

3. Running the example:

Run successfully!

Finally, note configuring Loginactivity in the Androidmanifest.xml file

Summarize

1. Realize parcelable interface to cover several methods and implement Parcelable.creator method;

2.bundle. putparcelable ("User", User1);//serialization

3.user = (user) intent. Getparcelableextra ("user");//Get Object

4.bundle. putparcelablearraylist ("List", (arraylist<user>) list);//Deposit into List Object array

5.list = Intent. Getparcelablearraylistextra ("list");//getparcelablearraylistextra method gets an array of objects

6. The system seems to provide only a list object array of delivery methods, how to pass the other collections? I hope Daniel will inform you.

Like a friend to order a praise Bai! Pay attention to the chant! Thank you

Intent object Passing (parcelable passing objects and collections of objects)