在开始之前，我浏览了以下问题:

Passing data between fragments: screen overlap How to pass values between Fragments

以及 Android 文档:

http://developer.android.com/training/basics/fragments/communicating.html

还有这篇文章:

http://manishkpr.webheavens.com/android-passing-data-between-fragments/

虽然上面提到的所有案例都与我所遇到的相似，但并不完全相同。我在这里遵循了一个很好的教程(我的部分代码基于这篇文章):

http://www.androidhive.info/2013/10/android-tab-layout-with-swipeable-views-1/

我有以下文件:

RegisterActivity.java
NonSwipeableViewPager.java
ScreenSliderAdapter.java
RegisterOneFragment.java
RegisterTwoFragment.java

以及以下布局:

activity_register.xml
fragment_register_one.xml
fragment_register_two.xml

我想要实现的是将一个可序列化对象从 RegisterFragmentOne 传递到 RegisterFragmentTwo。

到目前为止，这是我所做的(省略了一些代码):

RegisterActivity.java

public class RegisterActivity extends FragmentActivity
             implements RegisterOneFragment.OnEmailRegisteredListener{

    public static NonSwipeableViewPager viewPager;
    private ScreenSliderAdapter mAdapter;

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

        // Initilization
        mAdapter = new ScreenSliderAdapter(getSupportFragmentManager());
        viewPager = (NonSwipeableViewPager) findViewById(R.id.pager);
        viewPager.setAdapter(mAdapter);
    }

    public void onEmailRegistered(int position, Registration regData){
        Bundle args = new Bundle();
        args.putSerializable("regData", regData);
        viewPager.setCurrentItem(position, true);
    }
}

ScreenSliderAdapter.java

public class ScreenSliderAdapter extends FragmentPagerAdapter{

    public ScreenSliderAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int index) {

        switch (index) {
        case 0:
            return new RegisterOneFragment();
        case 1:
            return new RegisterTwoFragment();
        case 2:
            return new RegisterThreeFragment();
        }

        return null;
    }

    @Override
    public int getCount() {
        return 3;
    }
}

NonSwipeableViewPager.java(扩展 ViewPager 类，并覆盖以下内容)

@Override
public boolean onInterceptTouchEvent(MotionEvent arg0) {
    // Never allow swiping to switch between pages
    return false;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    // Never allow swiping to switch between pages
    return false;
}

RegisterOneFragment.java

public class RegisterOneFragment extends Fragment {
    OnEmailRegisteredListener mCallBack;
    public interface OnEmailRegisteredListener {
        /** Called by RegisterOneFragment when an email is registered */
        public void onEmailRegistered(int position, Registration regData);
    }

public void onAttach(Activity activity){
    super.onAttach(activity);

    // This makes sure that the container activity has implemented
    // the callback interface. If not, it throws an exception.
    try {
        mCallBack = (OnEmailRegisteredListener) activity;
    } catch (ClassCastException e) {
        throw new ClassCastException(activity.toString()
                + " must implement OnEmailRegisteredListener");
    }
}

... And some to execute some HTTP request via separate thread...
}

我想要完成的是，当用户按下 RegisterOneFragment 上的按钮时，数据将被发送到服务器(并通过 JSON 返回一些验证)。如果返回的数据有效，应用程序应转到下一个 fragment ，即 RegistrationTwoFragment。

我对如何在 fragment 之间传递对象感到困惑，因为我的 fragment 是使用适配器创建的。然后该适配器附加到我的 Activity。

谁能帮我解决这个问题？谢谢

编辑 1:

我试过像这样创建一个快捷方式(不幸的是不起作用):

在我创建的 RegisterActivity 中:

public Registration regData;

在 RegisterOneFragment 中:

/* PLACED ON POST EXECUTE */
((RegisterActivity)getActivity()).regData = regData;

最后在Re​​gisterTwoFragment中调用了

Registration regData;
regData = ((RegisterActivity) getActivity()).regData;

它抛出一个 nullPointerExceptions

编辑2

需要说明的是，RegisterActivty 包含多个 fragment 。用户在 fragment 之间导航的唯一方法是单击按钮。该 Activity 没有标签栏。

最佳答案

通过对自定义对象实现可序列化，可以轻松共享对象。我写了一个关于这个的教程 here .

来自 fragment 一:

android.support.v4.app.FragmentTransaction ft = 
    getActivity().getSupportFragmentManager().beginTransaction();
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
OfficeCategoryFragment frag = new OfficeCategoryFragment();

Bundle bundles = new Bundle();
Division aDivision = divisionList.get(position);

// ensure your object has not null
if (aDivision != null) {
    bundles.putSerializable("aDivision", aDivision);
    Log.e("aDivision", "is valid");
} else {
    Log.e("aDivision", "is null");
}
frag.setArguments(bundles);
ft.replace(android.R.id.content, frag);
ft.addToBackStack(null);
ft.commit();

fragment 二:

Bundle bundle = getArguments();
Division division= (Division) bundle.getSerializable("aDivision");
Log.e("division TEST", "" + division.getName());

关于java - Android:在 fragment 之间传递对象，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19998239/