android 怎么在activity之间传递List 类型的数据

Posted 2023-04-15

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Intent 传值可以传递对象,但是比较麻烦,要序列化

给你一种建议,将这个List转成JSON字符串

另外一个Activity再将这个字符串返序列即可

JSON与java对象相互转换google提供了一个非常牛X的工具Gson

用法非常简单,一行代码搞定

参考技术A 传
Bundle b=new Bundle();
b.putParcelableArrayList("comments",(ArrayList)comments);
intent.putExtras(b);

取
ArrayList<Comment> comments =(ArrayList)getIntent().getExtras().getParcelableArrayList("comments");

这里的实体类 Comment implements Serializable或者implements Parcelable，不然会报错

这是我自己用过的
参照这个写的

http://blog.csdn.net/xiaoxujie2007_/article/details/7481322

参考技术B Intent intent=new Intent();
intent.putExtra(name, value);

Android中如何使用Intent在Activity之间传递对象[使用Serializable或者Parcelable]

http://blog.csdn.net/cjjky/article/details/6441104

在Android中的不同Activity之间传递对象，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要实现Serializable接口，后面一种方法中的Object要实现Parcelable接口。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：

技术分享

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);
}
}