2
アクティビティからテキストビューを運ぶ別のフラグメントに時刻&の日付を含む文字列値を渡すことからNULL値があります。私のフラグメントのJavaクラス（Notifications.java）の別のものにこれらの値を渡す方法はありますか？アクティビティから別のフラグメントのテキストビューに文字列値（日付）を渡す
date = (TextView) view.findViewById(R.id.textDate);
date.setText(DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime()));
私はこのエラーを得た：
rogue.queue E/AndroidRuntime: FATAL EXCEPTION: main
Process: rogue.queue, PID: 20762
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at rogue.queue.MainActivity$1.onClick(MainActivity.java:76)
別のフラグメントに値を渡すために工場のボタンを使用した：
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Add a new queue", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
fragmentManager.beginTransaction().replace(R.id.content_main, new Notifications()).commit();
date = (TextView) view.findViewById(R.id.textDate);
date.setText(DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime()));
navigationView.setCheckedItem(R.id.nav_notifications);
}
});
ここフラグメント
public class Notifications extends Fragment {
TextView servingqueue;
TextView date;
String dateGET;
DatabaseReference mRootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference mServingQueue = mRootRef.child("ServingQueue");
public Notifications() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle pb=getArguments();
dateGET=pb.getString("date");
mServingQueue.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
Double number = dataSnapshot.getValue(Double.class);
servingqueue.setText(String.valueOf(number));
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
}
@Override
public void onDetach() {
super.onDetach();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_notifications, container, false);
// Inflate the layout for this fragmentid.queueServing);
servingqueue = (TextView) rootView.findViewById(R.id.queueServing);
return rootView;
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
date = (TextView) view.findViewById(R.id.textDate);
// date.setText(DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime()));
date.setText(dateGET);
}
}
ここにあります私mainactivity
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener, Home.OnFragmentInteractionListener {
//Read Firebase Database
private FirebaseAuth firebaseAuth;
private TextView textViewUserEmail;
private MenuItem nav_logout;
TextView servingqueue;
TextView date;
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Launches Home() fragment
fragmentManager.beginTransaction().replace(R.id.content_main, new Home()).commit();
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
navigationView.setCheckedItem(R.id.nav_home);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Add a new queue", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
// Queue.getQueue();
fragmentManager.beginTransaction().replace(R.id.content_main, new Notifications()).commit();
// date = (TextView) view.findViewById(R.id.textDate);
//
date.setText(DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime()));
Fragment fragment2=new Notifications();
Bundle arg= new Bundle();
arg.putString("date","DATE");
fragment2.setArguments(arg);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.content_main, fragment2);
fragmentTransaction.commit();
// fragmentManager.beginTransaction().replace(R.id.content_main,fragment2).commit();
navigationView.setCheckedItem(R.id.nav_notifications);
}
});
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
//User Profile Interface
firebaseAuth = FirebaseAuth.getInstance();
if (firebaseAuth.getCurrentUser() == null) {
startActivity(new Intent(this, Login.class));
}
FirebaseUser user = firebaseAuth.getCurrentUser();
View HeaderView = navigationView.getHeaderView(0);
textViewUserEmail = (TextView) HeaderView.findViewById(R.id.textViewUserEmail);
textViewUserEmail.setText("Welcome "+user.getEmail());
// nav_logout = (MenuItem) findViewById(R.id.nav_logout);
// nav_logout.setOnClickListener(this);
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
}
else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_home) {
fragmentManager.beginTransaction().replace(R.id.content_main, new Home()).commit();
} else if (id == R.id.nav_notifications) {
fragmentManager.beginTransaction().replace(R.id.content_main, new Notifications()).commit();
} else if (id == R.id.nav_settings) {
fragmentManager.beginTransaction().replace(R.id.content_main, new Settings()).commit();
} else if (id == R.id.nav_logout) {
firebaseAuth.signOut();
finish();
startActivity(new Intent (this, Login.class));
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
@Override
public void onFragmentInteraction(Uri uri) {
}
public void onClick(View v) {
Intent intent = new Intent (this, Scanner.class);
startActivity(intent);
}
}
は、ここで私が編集していますxmlです：
フラグメント：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="rogue.queue.Notifications"
android:id="@+id/notification_relative_layout">
<!-- TODO: Update blank fragment layout -->
<TextView
android:text="Your Number:"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="72dp"
android:id="@+id/textView3"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<TextView
android:text="0000"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView3"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:id="@+id/myqueue"
android:textSize="40sp" />
<TextView
android:text="Current Number:"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textView9"
android:layout_marginTop="62dp"
android:layout_below="@+id/myqueue"
android:layout_toStartOf="@+id/myqueue" />
<TextView
android:text="PLEASE BE SEATED"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="78dp"
android:id="@+id/textView15"
android:layout_below="@+id/queueServing"
android:layout_centerHorizontal="true" />
<TextView
android:text="-"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/queueServing"
android:layout_alignBaseline="@+id/textView9"
android:layout_toEndOf="@+id/myqueue" />
<TextView
android:text="YOU WILL BE SERVED SHORTLY"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="19dp"
android:id="@+id/textView14"
android:layout_below="@+id/textView15"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Welcome to Sunway Education Group"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<TextView
android:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textDate"
tools:text="00 - JAN - 0000"
android:layout_below="@+id/textView14"
android:layout_alignEnd="@+id/textView9" />
<Button
android:text="CANCEL QUEUE"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="21dp"
android:id="@+id/buttonQueueCancel"
android:background="@android:color/holo_red_light"
/>
ここでは、Fabがmainactivityへのリンクに置かれている場所のapp_main_barです.java
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
app:srcCompat="@drawable/ic_add_white_24px" />
日付=（のTextView）view.findViewById（R.id.textDate）。無効である。 textDateビューはアクティビティXMLまたはフラグメント内にありますか？ –
それは他の断片の中にあります –
あなたはあなたのようにこれを使うことはできません。その値をフラグメントに渡す必要があり、フラグメントのonViewCreatedメソッドはその値をtextviewに表示します。 –