Passing data through intent using Serializable

问题:

I\'ve implemented my class with serializable, but it still didn\'t work.

This is my class:

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();
    //  }

}

This is what I want to be passing.

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);

But still it didn\'t work. I don\'t know how to use Parcelable, so I use this instead.

回答1:

Try to pass the serializable list using Bundle.Serializable:

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

And in SomeClass Activity get it as:

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

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

回答2:

This code may help you:

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

Putting data. Create new Activity with extra:

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

Obtaining data from new activity:

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 
            }
//...

回答3:

I extended ρяσѕρєя K\'s answer to make the code full and workable. So, when you finish filling your \'all_thumbs\' list, you should put its content one by one into the bundle and then into the intent:

Bundle bundle = new Bundle();

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

intent.putExtras(bundle);

In order to get the extras from the intent, you need:

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();

Advantage of Serializable is its simplicity. However, I would recommend you to consider using Parcelable method when you need transfer many data, because Parcelable is specifically designed for Android and it is more efficient than Serializable. You can create Parcelable class using:

1. an online tool - parcelabler
2. a plugin for Android Studion - Android Parcelable code generator

回答4:

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

In SomeClass.java

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

回答5:

You need to create a Bundle and then use 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);

回答6:

Sending Data:

First make your serializable data by implement Serializable to your data class

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

Then put it into intent

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

Receiving Data:

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

回答7:

Create your custom object and implement Serializable. Next, you can use intent.putExtra(\"package.name.example\", <your-serializable-object>).

In the second activity, you read it using getIntent().getSerializableExtra(\"package.name.example\")

Otherwise, follow this and this page.

回答8:

In kotlin: Object class implements Serializable:

class MyClass: Serializable {
//members
}

At the point where the object sending:

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

At the fragment, where we want to get our object:

val bundle: Bundle? = arguments
    bundle?.let {
        val myObject = it.getSerializable(\"key\") as MyClass
        myObject.memberName?.let { it1 -> showShortToast(it1) }
    }