Tabbed活动中片段之间的相互作用

Question

我正在Tabbed活动中尝试两个片段之间的简单交互。

我有两个TextView、EditText和Button的布局。当按下FragmentOne中的Button时，我正试图实现将文本从FragmentOne的EditText移动到Fragment 2中的EdidText(或TextView(。但它不起作用。

在调试过程中没有任何问题。应用程序不会停止工作。

ViewPager或SectionsPagerAdapter有问题吗？

我有这两个碎片。碎片一：

public class FragmentOne extends Fragment {
TextView textView;
EditText editText;
Button button;
private OnFragmentOneInteractionListener mListener;
public FragmentOne()
{
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_one, container, false);
editText = (EditText) view.findViewById(R.id.fragOne_txb);
textView = (TextView) view.findViewById(R.id.fragTwo_header);
button = (Button) view.findViewById(R.id.fragOne_btn_to2);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v)
{
String text = editText.getText().toString();
mListener.onFragmentOneInteraction(text);
}
});
return view;
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentOneInteractionListener) {
mListener = (OnFragmentOneInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentOneInteractionListener");
}
}
@Override
public void onDetach() 
{
super.onDetach();
mListener = null;
}
public interface OnFragmentOneInteractionListener
{
void onFragmentOneInteraction(String string);
}

}

碎片二：

public class FragmentTwo extends Fragment{
private OnFragmentTwoInteractionListener mListener;
public EditText editText;
public FragmentTwo()
{
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_two, container, false);
editText = (EditText) view.findViewById(R.id.fragTwo_txb);
return view;
}
public void onUpdateEditText(String string)
{
this.editText.setText(string);
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentTwoInteractionListener) {
mListener = (OnFragmentTwoInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentTwoInteractionListener");
}
}
@Override
public void onDetach()
{
super.onDetach();
mListener = null;
}
public interface OnFragmentTwoInteractionListener
{
void onFragmentTwoInteraction(Uri uri);
}

}

这是我的主要活动：

public class MainActivity extends AppCompatActivity 
implements FragmentOne.OnFragmentOneInteractionListener,
FragmentTwo.OnFragmentTwoInteractionListener
{
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
mViewPager.addOnPageChangeListener(
new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.addOnTabSelectedListener(
new TabLayout.ViewPagerOnTabSelectedListener(mViewPager));
}
@Override
public void onFragmentOneInteraction(String string)
{
FragmentTwo fr2 = (FragmentTwo) getSupportFragmentManager().findFragmentById(R.id.fr2);
fr2.onUpdateEditText(string);
}
@Override
public void onFragmentTwoInteraction(Uri uri) 
{
}
public class SectionsPagerAdapter extends FragmentPagerAdapter
{
public SectionsPagerAdapter(FragmentManager fm)
{
super(fm);
}
@Override
public Fragment getItem(int position)
{
switch (position)
{
case 0:
FragmentOne fragmentOne = new FragmentOne();
return fragmentOne;
case 1:
FragmentTwo fragmentTwo = new FragmentTwo();
return fragmentTwo;
default:
return null;
}
}
@Override
public int getCount()
{
// Show 2 total pages.
return 2;
}
}
}

Answer 1

我刚刚尝试了您的代码，这是我为使其工作所做的更新。如果这是你想要的，请标记正确

private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
mViewPager.addOnPageChangeListener(
new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.addOnTabSelectedListener(
new TabLayout.ViewPagerOnTabSelectedListener(mViewPager));
}
@Override
public void onFragmentOneInteraction(String string)
{
fragmentTwo.onUpdateEditText(string);
/*FragmentTwo fr2 = (FragmentTwo) getSupportFragmentManager().findFragmentById(R.id.fr2);
fr2.onUpdateEditText(string);*/
}
@Override
public void onFragmentTwoInteraction(Uri uri)
{
}
FragmentTwo fragmentTwo = new FragmentTwo();
public class SectionsPagerAdapter extends FragmentPagerAdapter
{
public SectionsPagerAdapter(FragmentManager fm)
{
super(fm);
}
@Override
public Fragment getItem(int position)
{
switch (position)
{
case 0:
FragmentOne fragmentOne = new FragmentOne();
return fragmentOne;
case 1:
return fragmentTwo;
default:
return null;
}
}
@Override
public int getCount()
{
// Show 2 total pages.
return 2;
}
}

Answer 2

我建议使用getActivity((代替

if (getActivity() instanceof OnFragmentOneInteractionListener) {
mListener = (OnFragmentOneInteractionListener) getActivity();
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentOneInteractionListener");
}