(Android review)Activity之间的数据传递

一、基本知识点

1、Activity之间传递数据
1）传递基本类型或String

intent.putExtra("username", username);
 
 getIntent();
 intent.getStringExtra("username");

2）以bundle的形式传

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）传递自定义类型

1））implements Parcelable
2））重写以下两个方法
public int describeContents() {
 // TODO Auto-generated method stub
 return 0;
 }
 
 //把数据写入到Parcel对象
 public void writeToParcel(Parcel dest, int flags) {
 // TODO Auto-generated method stub
 dest.writeInt(id);
 dest.writeString(name);
 dest.writeInt(age);
 }


3））拷贝以下方法（把Person换成你的实际类型）


 public static final Parcelable.Creator<Person> CREATOR
     = new Parcelable.Creator<Person>() {
     //从Parcel对象里面读取数据
 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, "张信哲", 40);
     intent.putExtra("person", person);




Person person = intent.getParcelableExtra("person");

二、代码

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;

	@Override
	protected 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..", 21);
		intent.putExtra("person", person);
		
		
		startActivity(intent);

	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		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;
	
	
	@Override
	protected 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 + "zhangzetian's husband is : " + bundle.getString("zhangzetian") + " person: " + p.toString());
		
		
	}
	
}

三、源码下载：

四、效果图