Android fragment realizacja problem

Question

Oto mój xml dla mojego fragmentu:

<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="com.thenewjonathan.foodtracker.fragments.FoodItemDisplay" 
    > 
<TextView 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:textSize="50dp" 
     android:textStyle="bold" 
     android:text="blank" 
     android:id="@+id/foodItemNameView" 
     android:gravity="center" 
     android:layout_gravity="top|left|center" 
     android:textAlignment="center"/> 
<ImageView 
     android:contentDescription="@string/foodPicture" 
     android:layout_width="241dp" 
     android:layout_height="241dp" 
     android:layout_gravity="left|center_vertical" 
     android:background="@color/material_blue_grey_800" 
     android:layout_below="@id/foodItemNameView" 
     android:id="@+id/foodPic" 
     /> 
<RelativeLayout 
     android:layout_width="140dp" 
     android:layout_height="241dp" 
     android:layout_alignParentRight="true" 
     android:layout_below="@id/foodItemNameView" 
     android:layout_gravity="end|center_vertical" 
     android:gravity="center" 
     android:id="@+id/checkBoxGroup" 
     > 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Monday" 
      android:id="@+id/mondayBox" 
      android:layout_alignParentTop="true" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Tuesday" 
      android:id="@+id/tuesdayBox" 
      android:layout_below="@id/mondayBox" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Wednesday" 
      android:id="@+id/wednesdayBox" 
      android:layout_below="@id/tuesdayBox" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Thursday" 
      android:id="@+id/thursdayBox" 
      android:layout_below="@id/wednesdayBox" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Friday" 
      android:id="@+id/fridayBox" 
      android:layout_below="@id/thursdayBox" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Saturday" 
      android:id="@+id/saturdayBox" 
      android:layout_below="@id/fridayBox" 
      android:layout_alignParentStart="true"/> 
    <CheckBox 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="Sunday" 
      android:id="@+id/sundayBox" 
      android:layout_below="@id/saturdayBox" 
      android:layout_alignParentStart="true"/> 
</RelativeLayout> 

Oto mój plik Java do fragmentu: (FoodItem jest tylko obiekt niestandardowy używam do przechowywania informacji o każdy artykuł spożywczy, że fragment reprezentuje)

package com.thenewjonathan.foodtracker.fragments; 
import android.app.Activity; 
import android.app.Fragment; 
import android.os.Bundle; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.CheckBox; 
import android.widget.ImageView; 
import android.widget.TextView; 
import com.thenewjonathan.foodtracker.R; 
import com.thenewjonathan.foodtracker.enums.GoodBad; 
import com.thenewjonathan.foodtracker.objects.FoodItem; 

public class FoodItemDisplay extends Fragment 
{ 
    private static final String FOOD_ITEM_NAME = "blank"; 

    private FoodItem foodItem; 
    private String foodItemName; 

    private ImageView image; 
    private TextView itemNameView; 
    private CheckBox mondayBox; 
    private CheckBox tuesdayBox; 
    private CheckBox wednesdayBox; 
    private CheckBox thursdayBox; 
    private CheckBox fridayBox; 
    private CheckBox saturdayBox; 
    private CheckBox sundayBox; 

    public FoodItemDisplay() 
    { 
     setFoodItem(new FoodItem("blank", GoodBad.HEALTHY, "blank")); 
    } 



public static FoodItemDisplay newInstance(String inFoodItemName) 
    { 
     FoodItemDisplay fragment = new FoodItemDisplay(); 
     Bundle args = new Bundle(); 
     args.putString(FOOD_ITEM_NAME, inFoodItemName); 
     fragment.setArguments(args); 
     return fragment; 
    } 



@Override 
    public void onCreate(Bundle savedInstanceState) 
    { 
     super.onCreate(savedInstanceState); 
     if (getArguments() != null) 
     { 
      foodItemName = getArguments().getString(FOOD_ITEM_NAME); 
     } 
     itemNameView = (TextView) itemNameView.findViewById(R.id.foodItemNameView); 
     image = (ImageView) image.findViewById(R.id.foodPic); 
     mondayBox = (CheckBox) mondayBox.findViewById(R.id.mondayBox); 
     tuesdayBox = (CheckBox) tuesdayBox.findViewById(R.id.tuesdayBox); 
     wednesdayBox = (CheckBox) wednesdayBox.findViewById(R.id.wednesdayBox); 
     thursdayBox = (CheckBox) thursdayBox.findViewById(R.id.thursdayBox); 
     fridayBox = (CheckBox) fridayBox.findViewById(R.id.fridayBox); 
     saturdayBox = (CheckBox) saturdayBox.findViewById(R.id.saturdayBox); 
     sundayBox = (CheckBox) sundayBox.findViewById(R.id.sundayBox); 

     if (foodItem != null) 
     { 
      setValues(); 
     } 
    } 

    public void setValues() 
    { 
     if(itemNameView == null) 
     { 
      return; 
     } 
     itemNameView.setText(foodItem.getName()); 
     image.setImageResource(image.getResources() 
       .getIdentifier(foodItem.getImgName(), "drawable", this.getClass().getPackage().toString())); 
     mondayBox.setChecked(foodItem.isMonday()); 
     tuesdayBox.setChecked(foodItem.isTuesday()); 
     wednesdayBox.setChecked(foodItem.isWednesday()); 
     thursdayBox.setChecked(foodItem.isThursday()); 
     fridayBox.setChecked(foodItem.isFriday()); 
     saturdayBox.setChecked(foodItem.isSaturday()); 
     sundayBox.setChecked(foodItem.isSunday()); 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 
    { 
     return inflater.inflate(R.layout.food_item_display, container, false); 
    } 

    @Override 
    public void onAttach(Activity activity) 
    { 
     super.onAttach(activity); 
    } 

    @Override 
    public void onDetach() 
    { 
     super.onDetach(); 
    } 

    public FoodItem getFoodItem() 
    { 
     return foodItem; 
    } 

    public void setFoodItem(FoodItem foodItem) 
    { 
     this.foodItem = foodItem; 
    } 

    public String getFoodItemName() 
    { 
     return foodItemName; 
    } 

    public void setFoodItemName(String foodItemName) 
    { 
     this.foodItemName = foodItemName; 
    } 
} 

Oto klasa Kładę fragmentów w miejscu:

public class HealthyFoods extends Activity 
{ 
    private ArrayList<FoodItem> foodItemList; 

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

     foodItemList = new ArrayList<FoodItem>(); 
     foodItemList.add(new FoodItem("Turkey Burger", GoodBad.HEALTHY, "burger")); 

     FragmentManager fm = getFragmentManager(); 
     FragmentTransaction ft = fm.beginTransaction(); 
     for(FoodItem fi : foodItemList) 
     { 
      FoodItemDisplay fid = FoodItemDisplay.newInstance(fi.getName()); 
      fid.setFoodItem(fi); 
      fid.setValues(); 
      ft.add(R.id.healthyTab, fid); 
     } 
     ft.commit(); 
    } 
} 

Kiedy go uruchomić, dostaję ten ślad stosu:

java.lang.NullPointerException 
    at com.android.ddmlib.JdwpPacket.writeAndConsume(JdwpPacket.java:213) 
    at com.android.ddmlib.Client.sendAndConsume(Client.java:675) 
    at com.android.ddmlib.HandleHello.sendHELO(HandleHello.java:195) 
    at com.android.ddmlib.HandleHello.sendHelloCommands(HandleHello.java:66) 
    at com.android.ddmlib.Client.getJdwpPacket(Client.java:772) 
    at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:317) 
    at com.android.ddmlib.MonitorThread.run(MonitorThread.java:263) 

robiłem ok na tym projekcie, bo mogłam zobaczyć ślad stosu do kodu pisałem i znajdowaniu błędów. Ale kiedy uderzę w to, daje mi stosy śladów kodu, których nie napisałem. Wiem, że to oznacza, że ​​coś źle zrobiłem, ale Google nie jest bardzo pomocny w tej sprawie i kilka razy przejąłem ten kod i nie widzę niczego złego na podstawie dokumentacji każdego z obiektów i klas Używałem ... Czy ktoś kiedyś w to wpadł? Może masz jakieś pomysły na co patrzeć? A może po prostu masz odpowiedź? lol. Używam intellij-idea (nie androidowych studiów).

Dzięki! Jon

* FROM komentarzach poniżej * Oto adb wyjście dziennika:

DeviceMonitor: Adb rejected connection to client '27925': closed 
DeviceMonitor: Adb rejected connection to client '27952': closed 
DeviceMonitor: Adb rejected connection to client '28560': closed 
DeviceMonitor: Adb rejected connection to client '31166': closed 
DeviceMonitor: Adb rejected connection to client '31790': closed 
DeviceMonitor: Adb rejected connection to client '32138': closed 
DeviceMonitor: Adb rejected connection to client '578': closed 
DeviceMonitor: Adb rejected connection to client '578': closed 
ddms: null 
java.lang.NullPointerException 
    at com.android.ddmlib.JdwpPacket.writeAndConsume(JdwpPacket.java:213) 
    at com.android.ddmlib.Client.sendAndConsume(Client.java:675) 
    at com.android.ddmlib.HandleHello.sendHELO(HandleHello.java:195) 
    at com.android.ddmlib.HandleHello.sendHelloCommands(HandleHello.java:66) 
    at com.android.ddmlib.Client.getJdwpPacket(Client.java:772) 
    at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:317) 
    at com.android.ddmlib.MonitorThread.run(MonitorThread.java:263) 

ddms: null 
java.lang.NullPointerException 
    at com.android.ddmlib.JdwpPacket.writeAndConsume(JdwpPacket.java:213) 
    at com.android.ddmlib.Client.sendAndConsume(Client.java:675) 
    at com.android.ddmlib.HandleHello.sendHELO(HandleHello.java:195) 
    at com.android.ddmlib.HandleHello.sendHelloCommands(HandleHello.java:66) 
    at com.android.ddmlib.Client.getJdwpPacket(Client.java:772) 
    at com.android.ddmlib.MonitorThread.processClientActivity(MonitorThread.java:317) 
    at com.android.ddmlib.MonitorThread.run(MonitorThread.java:263) 

DeviceMonitor: Adb rejected connection to client '832': closed 
DeviceMonitor: Adb rejected connection to client '3083': closed 
DeviceMonitor: Adb rejected connection to client '5816': closed 
DeviceMonitor: Adb rejected connection to client '5847': closed 
DeviceMonitor: Adb rejected connection to client '6144': closed 
PropertyFetcher: AdbCommandRejectedException getting properties for device LGUS990611b931f: device offline 
PropertyFetcher: AdbCommandRejectedException getting properties for device LGUS990611b931f: device unauthorized. Please check the confirmation dialog on your device. 
PropertyFetcher: AdbCommandRejectedException getting properties for device LGUS990611b931f: device unauthorized. Please check the confirmation dialog on your device. 
PropertyFetcher: AdbCommandRejectedException getting properties for device LGUS990611b931f: device unauthorized. Please check the confirmation dialog on your device. 

New błąd teraz po pewnym przekonfigurowywaniu: Ok ... teraz nowy błędu ->

Caused by: java.lang.IllegalArgumentException: No view found for id 0x7f09005a (com.thenewjonathan.foodtracker:id/healthyTab) for fragment FoodItemDisplay{b5abff #0 id=0x7f09005a} 
      at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:886) 
      at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067) 
      at android.app.BackStackRecord.run(BackStackRecord.java:833) 
      at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1452) 
      at android.app.Activity.performStart(Activity.java:6035) 
      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2269) 
            at android.app.ActivityThread.startActivityNow(ActivityThread.java:2128) 
            at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:135) 
            at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:347) 
            at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:756) 
            at android.widget.TabHost.setCurrentTab(TabHost.java:420) 
            at android.widget.TabHost.addTab(TabHost.java:247) 
            at com.thenewjonathan.foodtracker.MainMenu.onCreate(MainMenu.java:30) 
            at android.app.Activity.performCreate(Activity.java:6020) 
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105) 
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2259) 
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2368) 
            at android.app.ActivityThread.access$800(ActivityThread.java:149) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1284) 
            at android.os.Handler.dispatchMessage(Handler.java:102) 
            at android.os.Looper.loop(Looper.java:135) 
            at android.app.ActivityThread.main(ActivityThread.java:5299) 
            at java.lang.reflect.Method.invoke(Native Method) 
            at java.lang.reflect.Method.invoke(Method.java:372) 

I dzieje się w oncreate z mojego menu głównego, który dodaje zakładki, gdy próbuję dodać kartę "zdrowy" do tabhost:

public class MainMenu extends ActivityGroup 
{ 
    @Override 
    protected void onCreate(Bundle savedInstanceState) 
    { 
     super.onCreate(savedInstanceState); 
     this.requestWindowFeature(Window.FEATURE_NO_TITLE); 
     setContentView(R.layout.main_menu); 

     TabHost container = (TabHost) findViewById(R.id.mainTabHost); 
     container.setup(this.getLocalActivityManager()); 
     TabSpec healthy = container.newTabSpec("Healthy Foods").setContent(new Intent(this, HealthyFoods.class)) 
       .setIndicator("Healthy Foods"); 
     TabSpec unHealthy = container.newTabSpec("Unhealthy Foods").setContent(new Intent(this, UnHealthyFoods.class)) 
       .setIndicator("Unhealthy Foods"); 

     container.addTab(healthy); 
     container.addTab(unHealthy); 
    } 
} 

Answer 1

Niewłaściwe odniesienie do swoich widoków w klasie onCreate() w klasie fragmentów. należy uzyskać ich referencje wewnątrz onCreateView() robi coś takiego:

View view = inflater.inflate(R.layout.food_item_display, container, false); 
itemNameView = (TextView) view.findViewById(R.id.foodItemNameView); 
image = (ImageView) view.findViewById(R.id.foodPic); 

Droga masz napisane, staramy się odwoływać poglądy przed dałeś im wartości, stąd NPE. Jeśli food_item_display jest w rzeczywistości układem nadrzędnym dla wszystkich tych elementów, powinieneś używać tego widoku, aby znaleźć inne według identyfikatora, tak jak to tutaj pokazałem.

Answer 2

Musisz użyć onActivityCreated lub onCreateView, aby uzyskać referencje, takie jak poniższy przykład. W tym celu nie można użyć onCreate, ponieważ fragment zostanie utworzony dopiero po onCreateView.

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 
{ 
    return inflater.inflate(R.layout.food_item_display, container, false); 
} 

@Override 
public void onActivityCreated(Bundle savedInstanceState){ 

    View _view = getView(); 

    itemNameView = (TextView) _view.findViewById(R.id.foodItemNameView); 
    image = (ImageView) _view.findViewById(R.id.foodPic); 
    mondayBox = (CheckBox) _view.findViewById(R.id.mondayBox); 
    tuesdayBox = (CheckBox) _view.findViewById(R.id.tuesdayBox); 
    wednesdayBox = (CheckBox) _view.findViewById(R.id.wednesdayBox); 
    thursdayBox = (CheckBox) _view.findViewById(R.id.thursdayBox); 
    fridayBox = (CheckBox) _view.findViewById(R.id.fridayBox); 
    saturdayBox = (CheckBox) _view.findViewById(R.id.saturdayBox); 
    sundayBox = (CheckBox) _view.findViewById(R.id.sundayBox); 

} 

Inny przykład:

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

    itemNameView = (TextView) _view.findViewById(R.id.foodItemNameView); 
    image = (ImageView) _view.findViewById(R.id.foodPic); 
    mondayBox = (CheckBox) _view.findViewById(R.id.mondayBox); 
    tuesdayBox = (CheckBox) _view.findViewById(R.id.tuesdayBox); 
    wednesdayBox = (CheckBox) _view.findViewById(R.id.wednesdayBox); 
    thursdayBox = (CheckBox) _view.findViewById(R.id.thursdayBox); 
    fridayBox = (CheckBox) _view.findViewById(R.id.fridayBox); 
    saturdayBox = (CheckBox) _view.findViewById(R.id.saturdayBox); 
    sundayBox = (CheckBox) _view.findViewById(R.id.sundayBox); 

    return _view; 
}