所以我提出一个实现了自定义类的Android应用程序传递给其他活动。我想创建一个Menu_Organizer类的对象到其他活动,但是在初始化对象并将它发送到下一个Activity之后,该对象为NULL。下面是类:自定义对象未通过的意图PutExtra
菜单项类
import java.io.Serializable;
public class Menu_Items implements Serializable {
private String Name = "";
private String Description = "";
private float Price = 0.0f;
private String Category = "";
/* Getters and Setters*/
}
菜单管理类:
public class Menu_Organizer implements Serializable {
ArrayList<String> Categories;
ArrayList<Menu_Items> Food;
// EDITED
public Menu_Organizer() {
Categories = new ArrayList<String>();
Food = new ArrayList<Menu_Items>();
}
/* Other class methods */
}
第一个活动(主)
public class MainActivity extends AppCompatActivity {
private Button btn;
public Menu_Organizer menu;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
onclick();
}
public void onclick() {
btn = (Button) findViewById(R.id. btn);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Menu_Organizer menu = new Menu_Organizer();
menu.New_Menu_Item("Carne", "Pollo", "Pollo Asado Rico!", 4.55f);
Intent activity2= new Intent(MainActivity.this,temp.class);
activity2.putExtra("Menu", menu);
startActivity(activity2);
}
});
}
}
次活动
public class temp extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_Second);
Bundle bundle = getIntent().getExtras();
Menu_Organizer menu = (Menu_Organizer) bundle.getSerializable("Menu");
String str= menu.Food.get(0).getName();
}
}
的'Intent'在'MainActivity'被打开''temp' Activity',但对方'你已经发布Activity'类是'秒'。 –
你应该显示你的New_Menu_Item实现。我的猜测是,在添加项目之前,您并未创建Food的新ArrayList实例。 –
http://stackoverflow.com/questions/4233873/how-do-i-get-extra-data-from-intent-on-android试过这个而不是'Bundle bundle = getIntent()。getExtras();'? – iCantSeeSharp