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
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);