工具栏视图引用从对话框片段返回后变为空
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【中文标题】工具栏视图引用从对话框片段返回后变为空【英文标题】：Toolbar views reference becomes null after returned from dialog fragment 【发布时间】：2017-12-21 22:27:47 【问题描述】：在片段中，我有自定义工具栏，其中包含搜索视图、文本视图和按钮。
@Override
public void onCreateOptionsMenu(final Menu menu, final MenuInflater inflater)
super.onCreateOptionsMenu(menu, inflater);
menu.clear();
inflater.inflate(R.menu.nearby_friends_menu, menu);
MenuItem item = menu.findItem(R.id.search_PTL);
//searchView=new SearchView(((Navigation_Drawer)getActivity()).getSupportActionBar().getThemedContext());
searchView = new SearchView(getActivity());
MenuItemCompat.setActionView(item, searchView);
Button voiceSearch = new Button(getActivity());
LinearLayout.LayoutParams navButtonsParams = new LinearLayout.LayoutParams(toolbar.getHeight() * 2 / 3, toolbar.getHeight() * 2 / 3);
voiceSearch.setBackgroundDrawable(getResources().getDrawable(R.drawable.ic_access_time_black_24dp));
((LinearLayout) searchView.getChildAt(0)).addView(voiceSearch, navButtonsParams);
((LinearLayout) searchView.getChildAt(0)).setGravity(Gravity.CENTER_VERTICAL);
voiceSearch.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
Bundle bundle = new Bundle();
bundle.putString("Calling", TAG);
datepicker.setArguments(bundle);
datepicker.show(getFragmentManager(), TAG);
);
searchView.setQueryHint("Search");
searchView.clearFocus(); // This is use for close the keyboard
return true;
单击按钮时，我在 dialogfragment 中打开一个日历，该日历将数据返回到片段，该片段已在 logcat 中成功打印。
public void searchItem(String query)
Log.d(TAG, "Query " + query + " " + searchView + " " + activityTitle + " " + switchButton); // All these views becomes null when get data here.
if (searchView != null)
Log.d(TAG, "Search View Is Not Null");
searchView.setQuery(query, false);
else
Log.d(TAG, "Search View Is NULL");
我尝试在此处将日期设置为 searchview，但 searchview 和其他视图变为空。那么，当我从 dialogfragment 获取数据时，如何避免视图变为空
这是完整的片段代码
public class ItemList extends Fragment
RecyclerView recyclerView;
RecyclerView.Adapter adapter;
RecyclerView.LayoutManager layoutManager;
onResultReceived listener,onRefresh_Interface;
ImageView appLogo;
TextView activityTitle;
Switch switchButton;
SearchView searchView;
Toolbar toolbar;
public static final String TAG="===Item List===";
DialogFragment datepicker;
public FriendsList()
// Required empty public constructor
@Override
public void onStart()
super.onStart();
Log.d(TAG,"On Start Calling");
@Override
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
Log.d(TAG,"ON CREATE CALLING ");
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
// Inflate the layout for this fragment
final View view=inflater.inflate(R.layout.activity_item_list,container,false);
recyclerView= (RecyclerView) view.findViewById(R.id.RecyclerViewForItemList);
adapter=new RecyclerFriendListAdapter(getActivity(),items);
layoutManager=new LinearLayoutManager(getActivity());
recyclerView.setLayoutManager(layoutManager);
recyclerView.setHasFixedSize(true);
recyclerView.setAdapter(adapter);
//Setting Toolbar For Current Fragment
toolbar= (Toolbar) getActivity().findViewById(R.id.Navigation_Drawer_toolbar);
appLogo= (ImageView) toolbar.findViewById(R.id.appLogo);
activityTitle= (TextView) toolbar.findViewById(R.id.activityTitle);
ImageButton done= (ImageButton) toolbar.findViewById(R.id.doneButton);
done.setVisibility(View.GONE);
appLogo.setImageResource(R.drawable.invent_x);
activityTitle.setText("Fav Items");
setHasOptionsMenu(true);
datepicker=new SelectDateFragment();
return view;
@Override
public void onAttach(Context context)
super.onAttach(context);
try
userData= (UserData) getActivity();
catch (ClassCastException e)
throw new ClassCastException(getActivity().toString()+" Must Implement Interface");
@Override
public void onResume()
super.onResume();
Log.d(TAG,"On Resume Calling");
// getActivity().invalidateOptionsMenu();
@Override
public void onCreateOptionsMenu(final Menu menu, final MenuInflater inflater)
super.onCreateOptionsMenu(menu, inflater);
menu.clear();
inflater.inflate(R.menu.nearby_friends_menu,menu);
final MenuItem switchItem=menu.findItem(R.id.toggle_button);
switchButton=new Switch(getActivity());
switchButton=switchItem.getActionView().findViewById(R.id.Switch_screen);
switchButton.setChecked(true);
MenuItemCompat.setActionView(switchItem,switchButton);
switchButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener()
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
if (isChecked)
Log.d(TAG,"Location Button Is Checked");
else
Log.d(TAG,"Location Button Is UnChecked");
);
MenuItem item=menu.findItem(R.id.search_PTL);
//searchView=new SearchView(((Navigation_Drawer)getActivity()).getSupportActionBar().getThemedContext());
searchView=new SearchView(getActivity());
MenuItemCompat.setActionView(item,searchView);
Button voiceSearch=new Button(getActivity());
LinearLayout.LayoutParams navButtonsParams = new LinearLayout.LayoutParams(toolbar.getHeight() * 2 / 3, toolbar.getHeight() * 2 / 3);
voiceSearch.setBackgroundDrawable(getResources().getDrawable(R.drawable.ic_access_time_black_24dp));
((LinearLayout)searchView.getChildAt(0)).addView(voiceSearch,navButtonsParams);
((LinearLayout)searchView.getChildAt(0)).setGravity(Gravity.CENTER_VERTICAL);
voiceSearch.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
Bundle bundle=new Bundle();
bundle.putString("Calling",TAG);
datepicker.setArguments(bundle);
datepicker.show(getFragmentManager(),TAG);
);
searchView.setQueryHint("Search ");
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener()
@Override
public boolean onQueryTextSubmit(String query)
//switchButton.setVisibility(View.VISIBLE);
Log.d(TAG,"Query Text Submit "+query);
getActivity().invalidateOptionsMenu();
searchView.clearFocus(); // This is use for close the keyboard
return true;
@Override
public boolean onQueryTextChange(String newText)
return true;
);
MenuItem.OnActionExpandListener expandListener=new MenuItem.OnActionExpandListener()
@Override
public boolean onMenuItemActionExpand(MenuItem menuItem)
Log.d(TAG,"On Menu Expand");
switchItem.setVisible(false);
return true;
@Override
public boolean onMenuItemActionCollapse(MenuItem menuItem)
Log.d(TAG,"On Menu Collapse");
// getActivity().invalidateOptionsMenu();
return true;
;
item.setOnActionExpandListener(expandListener);
public void searchUser(String query)
Log.d(TAG,"Query "+query+ " "+searchView+" "+activityTitle+" "+switchButton);// THESE VIEWS ALSO BECOME NULL AFTER GETTING RESULT FROM DATE PICKER DIALOG
dateQuery=query;
if (searchView!=null)
Log.d(TAG,"Search View Is Not Null");
searchView.setQuery(query,false);
else
Log.d(TAG,"Search View Is NULL");
【问题讨论】：
请提供完整的活动代码 @RahulKhurana 请检查编辑后的代码 【参考方案1】：从片段中的onActivityResult获取结果，而不是在片段中调用void方法。
点击按钮时调用对话框
`dialog.setTargetFragment(this, 1);
dialog.show(fragmentManager, TAG);`
通过onActivityResult将值发送回片段
`Bundle bundle = new Bundle();
bundle.putString("MyKey", Value);
Intent intent = new Intent().putExtras(bundle);
getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_OK, intent);
dismiss();`
在 Fragment 中处理结果
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data)
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1 && resultCode == Activity.RESULT_OK)
String myValue = data.getExtras().getString("Mykey");
Log.d(TAG,"My Value == "+myValue); //Handles your values here and views won't be null
参考：https://***.com/a/34527080/6527410
【讨论】：
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