使用Serializable通过intent传递数据

时间:2013-01-15 08:06:17

标签: java android android-intent

我已经使用serializable实现了我的类,但它仍然无效。

这是我的班级:

package com.ursabyte.thumbnail;

import java.io.Serializable;

import android.graphics.Bitmap;

public class Thumbnail implements Serializable {

    private static final long serialVersionUID = 1L;
    private String label = "";
    private Bitmap bitmap;

    public Thumbnail(String label, Bitmap bitmap) {
        this.label = label;
        this.bitmap = bitmap;
    }

    public void set_label(String label) {
        this.label = label;
    }

    public String get_label() {
        return this.label;
    }

    public void set_bitmap(Bitmap bitmap) {
        this.bitmap = bitmap;
    }

    public Bitmap get_bitmap(){
        return this.bitmap;
    }

    //  @Override
    //  public int compareTo(Thumbnail other) {
    //      if(this.label != null)
    //          return this.label.compareTo(other.get_label());
    //      else
    //          throw new IllegalArgumentException();
    //  }

}

这就是我想要传递的内容。

List<Thumbnail> all_thumbs = new ArrayList<Thumbnail>();
all_thumbs.add(new Thumbnail(string, bitmap));
Intent intent = new Intent(getApplicationContext(), SomeClass.class);
intent.putExtra("value", all_thumbs);

但它仍然没有用。我不知道如何使用Parcelable,所以我改用它。

11 个答案:

答案 0 :(得分:140)

尝试使用Bundle.Serializable传递可序列化列表:

Bundle bundle = new Bundle();
bundle.putSerializable("value", all_thumbs);
intent.putExtras(bundle);

在SomeClass Activity中将其命名为:

Intent intent = this.getIntent();
Bundle bundle = intent.getExtras();

List<Thumbnail> thumbs=
               (List<Thumbnail>)bundle.getSerializable("value");

答案 1 :(得分:11)

此代码可以为您提供帮助:

public class EN implements Serializable {
//... you don't need implement any methods when you implements Serializable
}

放置数据。使用额外内容创建新活动:

EN enumb = new EN();
Intent intent = new Intent(getActivity(), NewActivity.class);
intent.putExtra("en", enumb); //second param is Serializable
startActivity(intent);

从新活动中获取数据

public class NewActivity extends Activity {

    private EN en;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        try {
            super.onCreate(savedInstanceState);

            Bundle extras = getIntent().getExtras();
            if (extras != null) {
                en = (EN)getIntent().getSerializableExtra("en"); //Obtaining data 
            }
//...

答案 2 :(得分:6)

我扩展了ρяσѕρєяK的答案,使代码完整可行。因此,当您完成填写'all_thumbs'列表时,您应该将其内容逐个放入包中,然后放入意图中:

Bundle bundle = new Bundle();

for (int i = 0; i<all_thumbs.size(); i++)
bundle.putSerializable("extras"+i, all_thumbs.get(i));

intent.putExtras(bundle);

为了从意图中获取额外内容,您需要:

Bundle bundle = new Bundle();
List<Thumbnail> thumbnailObjects = new ArrayList<Thumbnail>();

// collect your Thumbnail objects
for (String key : bundle.keySet()) {
thumbnailObjects.add((Thumbnail) bundle.getSerializable(key));
}

// for example, in order to get a value of the 3-rd object you need to:
String label = thumbnailObjects.get(2).get_label();

Serializable的优点是简单。但是,我建议您在需要传输大量数据时考虑使用Parcelable方法,因为Parcelable是专为Android设计的,并且效率高于Serializable。您可以使用

创建Parcelable课程
  1. 在线工具 - parcelabler
  2. 适用于Android Studion的插件 - Android Parcelable code generator

答案 3 :(得分:3)

Intent intent = new Intent(getApplicationContext(),SomeClass.class);
intent.putExtra("value",all_thumbs);
startActivity(intent);

在SomeClass.java中

Bundle b = getIntent().getExtras();
if(b != null)
thumbs = (List<Thumbnail>) b.getSerializable("value");

答案 4 :(得分:2)

您需要创建Bundle,然后使用putSerializable

List<Thumbnail> all_thumbs = new ArrayList<Thumbnail>();
all_thumbs.add(new Thumbnail(string,bitmap));
Intent intent = new Intent(getApplicationContext(),SomeClass.class);

Bundle extras = new Bundle();

extras.putSerializable("value",all_thumbs);
intent.putExtras(extras);

答案 5 :(得分:2)

发送数据:

首先通过对数据类实施Serializable来制作可序列化的数据

public class YourDataClass implements Serializable {
String someText="Some text";
}

然后将其放入意图

YourDataClass yourDataClass=new YourDataClass();
Intent intent = new Intent(getApplicationContext(),ReceivingActivity.class);
intent.putExtra("value",yourDataClass);
startActivity(intent);

接收数据:

YourDataClass yourDataClass=(YourDataClass)getIntent().getSerializableExtra("value");

答案 6 :(得分:1)

创建自定义对象并实现Serializable。接下来,您可以使用intent.putExtra("package.name.example", <your-serializable-object>)

在第二项活动中,您使用getIntent().getSerializableExtra("package.name.example")

阅读

否则,请关注thisthis页。

答案 7 :(得分:1)

kotlin : Object类实现Serializable:

@Transactional(readOnly=false, rollbackFor=Exception.class)
public DboReturns addNewCurrencyPair(ExchangeDbo exchangeDbo, String currencyPairString) {  
    CurrencyPairDbo currencyPairDbo = exchangeDbo.addCurrencyPair(new CurrencyPair(currencyPairString));
    ExchangeDbo newExchangeDbo = exchangeRepository.save(exchangeDbo);

    return new DboReturns(newExchangeDbo, currencyPairDbo, null);
}

发送对象时:

class MyClass: Serializable {
//members
}

在片段中,我们想要获取对象:

val fragment = UserDetailFragment()
val bundle = Bundle()
bundle.putSerializable("key", myObject)
fragment.arguments = bundle

答案 8 :(得分:0)

通过意图发送List<MySerializableObject>时,我使用以下方法:

List<Thumbnail> thumbList = new ArrayList<>();
//Populate ...

Intent intent = new Intent(context, OtherClass.class);
intent.putExtra("ThumbArray", thumbList.toArray(new Thumbnail[0]));
//Send intent...

并像这样检索它:

Thumbnail[] thumbArr = (Thumbnail[]) getIntent().getSerializableExtra("ThumbArray");
if (thumbArr != null) {
    List<Thumbnail> thumbList = Arrays.asList(thumbArr);
}

答案 9 :(得分:0)

1-您正在使用的android.graphics.Bitmap无法实现Serializable类,因此您必须删除该类,然后它才能工作。

2-简要介绍一下,您可以访问如何pass data between intents

答案 10 :(得分:-1)

不要忘记在对象将使用的每个类中实现可序列化,就像对象列表一样。否则您的应用将崩溃。

示例:

public class City implements Serializable {

private List<House> house;

public List<House> getHouse() {
    return house;
}

public void setHouse(List<House> house) {
    this.house = house;
}}

那么House需要这样实现Serializable:

public class House implements Serializable {

private String name;

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}}

然后您可以使用:

Bundle bundle = new Bundle();
bundle.putSerializable("city", city);
intent.putExtras(bundle);

并使用以下命令进行检索:

Intent intent = this.getIntent();
Bundle bundle = intent.getExtras();
City city =  (City)bundle.getSerializable("city");