Activity之间通过Intent传递对象

Android Activity之间通过Intent传递对象

在Activity之间传递对象，这个对象须是可以序列化的，传递对象可以通过下面几种方式实现

• 类实现 Serializable,Java 提供的序列化的接口
• 类实现 Parcelable,Android提供的在移动端的序列化接口，效率更高

工程源码

Serializable

将类实现Serializable接口即可

public class CustomTest1 implements Serializable{
  public String name;
  public int age;
}

A Activity 发送数据

Intent intent = new Intent();
intent.setClass(this,IntentActivity2.class);
CustomTest1 test1 = new CustomTest1();
test1.name = "Kevin";
test1.age = 12;
Bundle b = new Bundle();
b.putSerializable("serial",test1);
intent.putExtras(b);

B Activity 接收数据

CustomTest1 test1 =  (CustomTest1) getIntent().getExtras().getSerializable("serial");
if(test1 != null){
    Log.e("tag","test1 name: "+test1.name+" age: "+test1.age);
}

Parcelable

将类实现Parcelable接口，必须重载相关的方法，必须创建一个CREATOR的变量,实现Parcelable接口，实现有点复杂
但是效率高

public class CustomTest2 implements Parcelable{
    public String name;
    public int age;

    public CustomTest2(){}

    public CustomTest2(Parcel p) {
        readFromParcel(p);
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(name);
        dest.writeInt(age);
    }

    @Override
    public int describeContents() {
        return 0;
    }

    private void readFromParcel(Parcel in ) {
        name = in.readString();
        age = in.readInt();
    }

    public static final Parcelable.Creator CREATOR = new Parcelable.Creator(){
        @Override
        public CustomTest2 createFromParcel(Parcel source) {
            return new CustomTest2(source);
        }

        @Override
        public CustomTest2[] newArray(int size) {
            return new CustomTest2[size];
        }
    };
}

A Activity 发送数据

Intent intent = new Intent();
intent.setClass(this,IntentActivity2.class);
CustomTest2 test2 = new CustomTest2();
test2.age = 14;
test2.name = "Jhon";
Bundle b = new Bundle();
b.putParcelable("parcle",test2);
intent.putExtras(b);

B Activity 接收数据

CustomTest2 test2 = getIntent().getExtras().getParcelable("parcle");
if(null != test2){
    Log.e("tag","test2 name: "+test2.name+" age: "+test2.age);
}

传递Bitmap对象

Activity之间可以传递bitmap对象，Bitmap的源码可以看到Bitmap已经实现了Parcelable的接口

public final class Bitmap implements Parcelable{}

A Activity 发送数据

Intent intent = new Intent();
intent.setClass(this,IntentActivity2.class);
intent.putExtra("bitmap", bitmap);

B Activity 接收数据

Bitmap bitmap = getIntent().getParcelableExtra("bitmap");

数据不能传递太大的数据，如果数据太大户籍引起异常，可以先对bitmap做一下压缩，然后在传递

A Activity 发送数据(压缩bitmap)

ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPG, 100, stream);
byte[] bytes = stream.toByteArray();
intent.putExtra("bitmapbytes",bytes);

B Activity 接收数据

byte[] bytes = getIntent().getByteArrayExtra("bitmapbytes");
Bitmap bmp = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);

工程源码