android - 在 Activity 之间传递参数 - 空

Question

我正在发送实现可序列化的自定义类的对象:

public class MyObject extends ParseObject implements Serializable {
private static final long serialVersionUID = 1L;
public MyObject() {
}
public String getTitle() {
    return getString("title");
}
public void setTitle(String title) {
    put("title", title);
}
public ParseFile getParseFile() {
    return getParseFile("file");
}
public void setParseFile(ParseFile file) {
    put("file", file);
}
}

该类包含 atm 一个字符串和一个 ParseFile。

我正在尝试将一个对象从一个 Activity 传递到另一个。

private void editMyObject(MyObject myObject) {
    Intent intent = new Intent(AActivity.this, BActivity.class);
    intent.putExtra("MyObject", myObject);  
    Toast.makeText(getApplicationContext(), "OUT: "+myObject.getTitle(), Toast.LENGTH_SHORT).show(); // here i get the content, proper string
    startActivity(intent);
}

在“接收者” Activity 中:

protected void onCreate(Bundle savedInstanceState) {
    ...

    Intent intent = getIntent();
    myObject = (MyObject)intent.getSerializableExtra("MyObject");
    if (myObject != null) {
        editText.setText(myObject.getTitle());
    }
    Toast.makeText(getApplicationContext(), "IN: "+myObject.getTitle(), Toast.LENGTH_SHORT).show(); // here is null
}

我做错了什么..？我在 SOF 上关注了另一个问题，但这没有帮助；)顺便说一句:不，ParseFile 是来自 Parse developers 的类

Answer 1

我猜它应该是这样的 ParsObject implements Serializable 因为根据关于 Serializable 的主题，如果 Super 类不可序列化，则实例的状态不会被维护。因此尝试使 ParseObject 类可序列化并查看结果

尝试这样的事情

public class MyObject implements Serializable {

private ParseObject parseObject;

public MyObject() {
    parseObject = new ParseObject();
}

public String getTitle() {
    return parseObject.getString("title");
}

public void setTitle(String title) {
    parseObject.put("title", title);
}

public ParseFile getParseFile() {
    return parseObject.getParseFile("file");
}

public void setParseFile(ParseFile file) {
    parseObject.put("file", file);
}

private void writeObject(java.io.ObjectOutputStream stream)
        throws IOException {
    stream.writeObject(parseObject);
}

private void readObject(java.io.ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
    parseObject = (ParseObject) stream.readObject();
}
}