(Android Review) Data transfer between the activity

I. Basic points of knowledge

1. Transfer data between activity
1) Pass basic type or string
Intent.putextra ("username", username);

Getintent ();
Intent.getstringextra ("username");


2) transmission in the form of bundles

Bundle bundle = new bundle ();
Bundle.putstring ("username", username);
Bundle.putstring ("password", password);

Intent.putextras (bundle);




Bundle bundle = Intent.getextras ();
String username = bundle.getstring ("username");
String Password = bundle.getstring ("password");


3) Passing Custom types


1)) Implements Parcelable
2)) Rewrite the following two methods
public int describecontents () {
TODO auto-generated Method Stub
return 0;
}

Write data to the parcel object
public void Writetoparcel (Parcel dest, int flags) {
TODO auto-generated Method Stub
Dest.writeint (ID);
Dest.writestring (name);
Dest.writeint (age);
}


3) Copy the following method (change person to your actual type)


public static final Parcelable.creator<person> Creator
= new Parcelable.creator<person> () {
Reading data from the parcel object
Public person Createfromparcel (Parcel in) {
return new person (in);
}

Public person[] NewArray (int size) {
return new Person[size];
}
};

Public person (Parcel in) {
TODO auto-generated Constructor stub
id = in.readint ();
Name = In.readstring ();
Age = In.readint ();
}




person person = new person (100, "Jeff Chang", 40);
Intent.putextra ("person", person);




Person person = Intent.getparcelableextra ("person");

Second, the Code

1, Mainactivity

Package Com.example.parsedata;import Android.os.bundle;import Android.app.activity;import android.content.Intent; Import Android.view.menu;import Android.view.view;import Android.widget.edittext;public class MainActivity extends Activity {private EditText et_username;private EditText et_password; @Overrideprotected void OnCreate (Bundle Savedinstancestate) {super.oncreate (savedinstancestate); Setcontentview (r.layout.main); et_username = (EditText) Findviewbyid (r.id.et_username); Et_password = (EditText) Findviewbyid (R.id.et_password);} public void Enter (view view) {String username = Et_username.gettext (). toString (); String password = Et_password.gettext (). toString (); Intent Intent = new Intent (this, mainactivity2.class); Intent.putextra ("username", username); Intent.putextra ("Password", password); Bundle bundle = new bundle (); Bundle.putstring ("Zhangzetian", "Huangjundong"); Intent.putextras (bundle); person person = new person (2, "Hjd is a handsomeboy.."), Intent.putextra (' person ', person); startAcTivity (intent);} @Overridepublic boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds items to the action bar if it is PR Esent.getmenuinflater (). Inflate (R.menu.main, menu); return true;}}

2, MainActivity2

Package Com.example.parsedata;import Android.app.activity;import Android.content.intent;import android.os.Bundle; Import Android.view.view;import Android.widget.edittext;import Android.widget.textview;public class MainActivity2 Extends Activity {private TextView tv_info; @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate); Setcontentview (r.layout.main2); tv_info = (TextView) Findviewbyid (r.id.tv_info); Intent Intent = Getintent (); String username = Intent.getstringextra ("username"); String Password = Intent.getstringextra ("password"); Bundle bundle = Intent.getextras (); Person p = Intent.getparcelableextra ("person"), Tv_info.settext ("Username:" + username + ", password:" + password + "Zhang Zetian ' s husband is: "+ bundle.getstring (" Zhangzetian ") +" Person: "+ p.tostring ());}}

Third, the source code download:

http://download.csdn.net/detail/caihongshijie6/7792903

Four