我有两门课。第一个是活动,第二个是片段,其中有一些EditText。在活动中,我有一个带有async-task的子类,在方法doInBackground中,我得到了一些结果,我保存到变量中。我怎么能把这个变量从子类“我的活动”到这个片段?


当前回答

你可以在片段中创建一个setter方法。然后在Activity中,当引用片段时,调用setter方法并将Activity中的数据传递给它

其他回答

使用Fragments (F)的基本想法是在android应用程序中创建可重用的自我维持UI组件。这些片段包含在活动中,有常见的(最好的)方法来创建从A -> F和F-A的通信路径,这是必须通过一个活动在F-F之间进行通信,因为这样只有片段变得解耦和自我维持。

因此,从A -> F传递数据将是相同的ρ σ η η K.除了这个答案,在一个活动内创建Fragments之后,我们还可以将数据传递给Fragments调用Fragments中的方法。

例如:

    ArticleFragment articleFrag = (ArticleFragment)
                    getSupportFragmentManager().findFragmentById(R.id.article_fragment);
    articleFrag.updateArticleView(position);

我在这里@ stackoverflow.com找到了很多答案,但这绝对是正确的答案:

“发送数据从活动碎片在android”。

活动:

        Bundle bundle = new Bundle();
        String myMessage = "Stackoverflow is cool!";
        bundle.putString("message", myMessage );
        FragmentClass fragInfo = new FragmentClass();
        fragInfo.setArguments(bundle);
        transaction.replace(R.id.fragment_single, fragInfo);
        transaction.commit();

片段:

读取片段中的值

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        Bundle bundle = this.getArguments();
        String myValue = bundle.getString("message");
        ...
        ...
        ...
        }

或者只是

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        String myValue = this.getArguments().getString("message");
        ...
        ...
        ...
        }

从Activity中,你用Bundle发送数据为:

Bundle bundle = new Bundle();
bundle.putString("data", "Data you want to send");

// Your fragment
MyFragment obj = new MyFragment();
obj.setArguments(bundle);

并在Fragment的onCreateView方法中获取数据:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 
{
    String data = getArguments().getString("data");// data which sent from activity  
    return inflater.inflate(R.layout.myfragment, container, false);
}

你也可以从片段访问活动数据:

活动:

public class MyActivity extends Activity {

    private String myString = "hello";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);
        ...
    }

    public String getMyData() {
        return myString;
    }
}

片段:

public class MyFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        MyActivity activity = (MyActivity) getActivity();
        String myDataFromActivity = activity.getMyData();
        return view;
    }
}

在片段和活动之间传递数据的最聪明的方法是创建一个变量,例如:

class StorageUtil {
  public static ArrayList<Employee> employees;
}

然后通过onActivityCreated方法将数据从fragment传递给activity:

//a field created in the sending fragment
ArrayList<Employee> employees;

@Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
         employees=new ArrayList();

       //java 7 and above syntax for arraylist else use employees=new ArrayList<Employee>() for java 6 and below

     //Adding first employee
        Employee employee=new Employee("1","Andrew","Sam","1984-04-10","Male","Ghanaian");
        employees.add(employee);

      //Adding second employee
       Employee employee=new Employee("1","Akuah","Morrison","1984-02-04","Female","Ghanaian");
         employees.add(employee);

        StorageUtil.employees=employees;
    }

现在您可以获得StorageUtil的值。来自各地的员工。 古德勒克!