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如何使用viewpager从输入数据片段中获取值

fragment android-viewpager mobile android-activity android

rizkygum · 技术社区 · 7 年前

碎片1=编辑文本1,碎片2=编辑文本2,碎片3=编辑文本3&碎片4=按钮保存

在片段4中,只有一个保存按钮可以从片段1、2和3中检索数据但当我单击按钮Save时,来自fragment1的数据总是空的

主要活动:

public class MainActivity extends AppCompatActivity {

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

    ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
    ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
    adapter.addFragment(new FragmentOne(), "FRAG1");
    adapter.addFragment(new FragmentTwo(), "FRAG2");
    adapter.addFragment(new FragmentThree(), "FRAG3");
    adapter.addFragment(new FragmentFour(), "FRAG4");
    viewPager.setAdapter(adapter);

    TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(viewPager);
}

class ViewPagerAdapter extends FragmentPagerAdapter {
    private final List<Fragment> mFragmentList = new ArrayList<>();
    private final List<String> mFragmentTitleList = new ArrayList<>();

    public ViewPagerAdapter(FragmentManager manager) {
        super(manager);
    }

    @Override
    public Fragment getItem(int position) {
        return mFragmentList.get(position);
    }

    @Override
    public int getCount() {
        return mFragmentList.size();
    }

    public void addFragment(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return mFragmentTitleList.get(position);
    }
}

public class FragmentOne extends Fragment {
public FragmentOne() {
    // Required empty public constructor
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment

    return inflater.inflate(R.layout.fragment_one, container, false);
}

}

public class FragmentFour extends Fragment {

private EditText txt1, txt2, txt3;
private Button button;

public FragmentFour() {
    // Required empty public constructor
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view =  inflater.inflate(R.layout.fragment_four, container, false);

    txt1 = (EditText)getActivity().findViewById(R.id.txt1);
    txt2 = (EditText)getActivity().findViewById(R.id.txt2);
    txt3 = (EditText)getActivity().findViewById(R.id.txt3);

    button = (Button)view.findViewById(R.id.button);
    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            getData();
        }
    });
    return view;
}

private void getData() {
    String fragment1 = txt1.getText().toString();
    String fragment2 = txt2.getText().toString();
    String fragment3 = txt3.getText().toString();
}

来自文本1(片段)的数据始终为空:

Data from text1 (fragment)always null

我该怎么解决这个问题?

5 回复 | 直到 7 年前

ND1010_ 7 年前

你必须使用存储FragmentOne数据,FragmentTwo数据,然后在保存按钮上检索到FragmentTree

AskNilesh 7 年前

为此,您可以使用共享首选项

创建共享引用

SharedPreferences pref = getApplicationContext().getSharedPreferences("DATA", MODE_PRIVATE); 
Editor editor = pref.edit();
editor.putString("EDITEXT1", "string value");  // Saving string data of your editext
editor.commit(); // commit and save your data in to SharedPreferences

现在按以下代码检索数据

SharedPreferences pref = getApplicationContext().getSharedPreferences("DATA", MODE_PRIVATE); 
String email=pref.getString("EDITEXT1", "");       // Saving string data of your editext

Navneet Krishna 7 年前

论据例如,在片段之间传递数据

Bundle bundle = new Bundle();
bundle.putString("someEditTextData",someEditTextData);
SomeFragment fragment = new SomeFragment ();
fragment.setArguments(bundle);

并检索所需片段中的数据,如下图所示

Bundle args = getArguments();
    if (args != null) {
        showReceivedData.setText(args.getString("someEditTextData"));
    }

Shailendra Yadav 7 年前

((MainActivity) getActivity()).filedName.setFragmentOneData(data);

-1

J Ramesh 7 年前

viewPager始终加载两侧的1个连续页面如果要访问片段1 editText数据,请添加此行

 viewPager.setOffscreenPageLimit(4);

使用静态变量