如何将数据从Activity发送到Fragment

Question

我知道这里有很多关于这方面的话题.我也多次阅读文档,但我找不到将数据从活动传递到片段的最佳方法.

我希望能够使用带选项卡的滑动视图在两个不同的布局(列表和地图)中显示我的可搜索活动的结果.我必须将2个数据传递给片段:"currentLocation"是当前用户位置,"result"是对象列表.

我已经省略了代码的某些部分,以使其更容易理解.

SearchableActivity.java

public class SearchableActivity extends ActionBarActivity implements TabListener {

    List<PlaceModel> result = new ArrayList<PlaceModel>();
    private SearchView mSearchView;
    private String currentLocation;

    AppSectionsPagerAdapter mAppSectionsPagerAdapter;
        ViewPager mViewPager;

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

    setContentView(R.layout.activity_searchable);

    final ActionBar actionBar = getSupportActionBar();
    actionBar.setHomeButtonEnabled(true);
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    mAppSectionsPagerAdapter = new AppSectionsPagerAdapter(getSupportFragmentManager());

    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mAppSectionsPagerAdapter);
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
        @Override
        public void onPageSelected(int position) {
            actionBar.setSelectedNavigationItem(position);
        }
    });

    actionBar.addTab(actionBar.newTab().setText("List").setTabListener(this));
    actionBar.addTab(actionBar.newTab().setText("Map").setTabListener(this));

    // get currentLocation here

    handleIntent(getIntent());
}

@Override
protected void onNewIntent(Intent intent) {
    handleIntent(intent);
}

private void handleIntent(Intent intent) {

    if (Intent.ACTION_SEARCH.equals(intent.getAction())) {

        final String query = intent.getStringExtra(SearchManager.QUERY);

        // get result here
    }
}

@Override
public void onTabReselected(Tab arg0, FragmentTransaction arg1) {
    // TODO Auto-generated method stub

}

@Override
public void onTabSelected(Tab tab, FragmentTransaction arg1) {
    mViewPager.setCurrentItem(tab.getPosition());
}

@Override
public void onTabUnselected(Tab arg0, FragmentTransaction arg1) {
    // TODO Auto-generated method stub

}

}

PlaceListFragment.java

public class PlaceListFragment extends Fragment {
    ListView listViewData;
    PlaceAdapter placeAdapter;
    List<PlaceModel> result = new ArrayList<PlaceModel>();

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_list, container, false);
        Bundle args = getArguments();
        listViewData = (ListView) rootView.findViewById(android.R.id.list);
        // I will pass result and currentLocation here
        placeAdapter = new PlaceAdapter(getActivity(), R.layout.fragment_list_item, result, currentLocation);
        listViewData.setAdapter(placeAdapter);
        return rootView;
    }
}

AppSectionsPagerAdapter.java

public class AppSectionsPagerAdapter extends FragmentPagerAdapter {

final int PAGE_COUNT = 2;

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

@Override
public Fragment getItem(int arg0) {
    Bundle data = new Bundle();
    switch(arg0) {
        case 0:
            PlaceListFragment fragment1 = new PlaceListFragment();
            fragment1.setArguments(data);
            return fragment1;
        default:
            PlaceListFragment fragment2 = new PlaceListFragment();
            fragment2.setArguments(data);
            return fragment2;
    }
}

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

Answer 1

从活动中您可以按意图发送数据:

Bundle bundle=new Bundle();
bundle.putString("name", "From Activity");
  //set Fragmentclass Arguments
Fragmentclass fragobj=new Fragmentclass();
fragobj.setArguments(bundle);

并在Fragment onCreateView方法中:

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
    Bundle savedInstanceState) {
          String strtext=getArguments().getString("name");

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

Answer 2

在Activity onCreate中查找片段并将数据设置为您在片段中编写的方法:

        ExampleFragment rf =  (ExampleFragment) getSupportFragmentManager().findFragmentById(R.id.exampleFragment);

    if(rf!=null){
    rf.setExample(currentExample);
    }

"CurrentExample"是您要发送到片段中"setExample"方法的任何内容.

public void setExample(ExampleObject currentExample){

    currentExampleInFragment = currentExample;

}

您可以使用Fragment的onActivityCreated方法中的数据.

不确定这是不是一个好的解决方案,但我发现它是传递对象最简单的解决方案.

Answer 3

通常,活动将引用其片段.在你的SearchableActivity.java是,你还装载PlaceListFragment.java无论是在setContentView(activity_searchable.xml);或您需要创建片段的实例,并添加/替换使用的片段FragmentTransaction.

你可以在这里找到一个关于如何在片段之间或在活动和片段之间进行通信的好例子.

培训链接

Answer 4

Bundle bundle = new Bundle();
bundle.putString("edttext", "From Activity");
// set Fragmentclass Arguments
Fragmentclass fragobj = new Fragmentclass();
fragobj.setArguments(bundle);

并在 Fragment onCreateView 方法中：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    String strtext = getArguments().getString("edttext");    
    return inflater.inflate(R.layout.fragment, container, false);
}

在此处查看详细答案..