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  • 【转】Android中如何使用Bundle传递对象[使用Serializable或者Parcelable] -- 不错

    原文网址：http://www.jcodecraeer.com/a/anzhuokaifa/androidkaifa/2012/1211/694.html

    Android中Bundle类的作用

    Bundle类用作携带数据，它类似于Map，用于存放key-value名值对形式的值。相对于Map，它提供了各种常用类型的putXxx()/getXxx()方法，如:putString()/getString()和putInt()/getInt()，putXxx()用于往Bundle对象放入数据，getXxx()方法用于从Bundle对象里获取数据。Bundle的内部实际上是使用了HashMap类型的变量来存放putXxx()方法放入的值。

    用Bundle可以在Activity中传递基本数据类型，比如int、float、string等，但是现在的需求是如何在Activity中传递对象实例呢？就我目前所知的有两种，分别是java中Serializable和Android新引进的Parcelable方法。

     我们可以考虑采用Bundle.putSerializable(Key,Object);也可以考虑采用Bundle.putParcelable(Key, Object);其中前面一种方法中的Object必须要实现Serializable接口，后面一种方法中的Object必须要实现Parcelable接口。如果没有实现这两个接口之一，那么我们可以使用Bundle.putSerializable(Key,Object)或者Bundle.putParcelable(Key, Object)，但起不到任何作用，下面我们以一个完整的例子来说明。

    1.新建一个Android的工程，其中该工程的目录结构如下图：

    2. 修改main.xml布局文件。布局文件的源码如下：

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    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:orientation="vertical"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >
    <TextView  
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello"
        />
        <Button
           android:id="@+id/serButton"
           android:layout_width="fill_parent"
           android:layout_height="wrap_content"
           android:text="Serializable"/>
        <Button
           android:id="@+id/parButton"
           android:layout_width="fill_parent"
           android:layout_height="wrap_content"
           android:text="Parcelable"/>
    </LinearLayout>

    3.在工程的src目录下新建一个实体类包，命名为com.andy.entity.同时在该package中添加两个实体类，一个是Person.java，该类实现Serializable接口；一个是Police.java，该类实现Parcelable接口。代码分别如下：

    Person.java:

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    package com.andy.entity;
       
    import java.io.Serializable;
       
    public class Person implements Serializable {
           
        private static final long serialVersionUID = -6919461967497580385L;
           
        private String name;
        private int age;
           
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public int getAge() {
            return age;
        }
        public void setAge(int age) {
            this.age = age;
        }
    }

    Police.java:

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    package com.andy.entity;
       
    import android.os.Parcel;
    import android.os.Parcelable;
       
    public class Police implements Parcelable {
           
        private String name;
        private int workTime;
       
        public String getName() {
            return name;
        }
       
        public void setName(String name) {
            this.name = name;
        }
       
        public int getWorkTime() {
            return workTime;
        }
       
        public void setWorkTime(int workTime) {
            this.workTime = workTime;
        }
           
        public static final Parcelable.Creator<Police> CREATOR = new Creator<Police>() {
       
            @Override
            public Police createFromParcel(Parcel source) {
                Police police = new Police();
                police.name = source.readString();
                police.workTime = source.readInt();
                return police;
            }
       
            @Override
            public Police[] newArray(int size) {
                return new Police[size];
            }
        };
       
        @Override
        public int describeContents() {
            return 0;
        }
       
        @Override
        public void writeToParcel(Parcel parcel, int flags) {
            parcel.writeString(name);
            parcel.writeInt(workTime);
        }
    }

    4.在包com.andy.testdemo中修改TestActivity.java类，同时在该包中添加类SerializableDemo和ParcelableDemo，分别继承了Activity类和分别显示Person对象和Police对象的数据。代码如下：

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    package com.andy.testdemo;
       
    import com.andy.entity.Person;
    import com.andy.entity.Police;
       
    import android.app.Activity;
    import android.content.Intent;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.Button;
       
    public class TestActivity extends Activity {
        private Button sButton,pButton;
        public final static String SER_KEY = "com.andy.ser";
        public final static String PAR_KEY = "com.andy.par";
           
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
               
            sButton = (Button)findViewById(R.id.serButton);
            sButton.setOnClickListener(new View.OnClickListener() {
                   
                @Override
                public void onClick(View v) {
                    SerializeMethod();
                }
            });
               
            pButton = (Button)findViewById(R.id.parButton);
            pButton.setOnClickListener(new View.OnClickListener() {
                   
                @Override
                public void onClick(View v) {
                    PacelableMethod();
                }
            });
        }
           
        /**
         * Serializeable传递对象的方法
         */
        private void SerializeMethod(){
            Person mPerson = new Person();   
            mPerson.setName("andy");   
            mPerson.setAge(26);   
            Intent mIntent = new Intent(this,SerializableDemo.class);   
            Bundle mBundle = new Bundle();   
            mBundle.putSerializable(SER_KEY,mPerson);   
            mIntent.putExtras(mBundle);   
               
            startActivity(mIntent);   
        }
           
        /**
         * Pacelable传递对象方法 
         */
        private void PacelableMethod(){
            Police mPolice = new Police();   
            mPolice.setName("I am Police");      
            mPolice.setWorkTime(2008);   
            Intent mIntent = new Intent(this,ParcelableDemo.class);   
            Bundle mBundle = new Bundle();   
            mBundle.putParcelable(PAR_KEY, mPolice);   
            mIntent.putExtras(mBundle);   
            
            startActivity(mIntent);   
        }
    }

    SerializableDemo.java类

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    package com.andy.testdemo;
       
    import com.andy.entity.Person;
       
    import android.app.Activity;
    import android.os.Bundle;
    import android.widget.TextView;
       
    public class SerializableDemo extends Activity {
       
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
               
            TextView mTextView = new TextView(this);   
            Person mPerson = (Person)getIntent().getSerializableExtra(TestActivity.SER_KEY);   
            mTextView.setText("You name is: " + mPerson.getName() + "/n"+   
                              "You age is: " + mPerson.getAge());   
       
            setContentView(mTextView);   
        }
       
    }

    ParcelableDemo.java类：

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    package com.andy.testdemo;
       
    import com.andy.entity.Police;
       
    import android.app.Activity;
    import android.os.Bundle;
    import android.widget.TextView;
       
    public class ParcelableDemo extends Activity {
       
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
               
            TextView mTextView = new TextView(this);   
            Police mPolice = (Police)getIntent().getParcelableExtra(TestActivity.PAR_KEY);   
            mTextView.setText("Police name is: " + mPolice.getName()+"/n"+   
                              "WorkTime is: " + mPolice.getWorkTime() + "/n");   
            setContentView(mTextView);   
        }
       
    }

    5.在AndroidManifest.xml文件中为新添加的两个Activity进行注册。

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    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.andy.testdemo"
          android:versionCode="1"
          android:versionName="1.0">
        <application android:icon="@drawable/icon" android:label="@string/app_name">
            <activity android:name=".TestActivity"
                      android:label="@string/app_name">
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />
                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
            <activity android:name=".SerializableDemo"/>
            <activity android:name=".ParcelableDemo"/>
        </application>
        <uses-sdk android:minSdkVersion="8" />
       
    </manifest>
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  • 原文地址：https://www.cnblogs.com/wi100sh/p/5403841.html
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