原因：java.lang.IllegalStateException：指定された子がすでに親を持っています

Question

私はこのスピナーをアクティビティのツールバーに入れる必要があるカスタムスピナーを作成しました。これが私の活動

package abtech.waiteriano.com.waitrer; 

import android.app.FragmentManager; 
import android.content.Context; 
import android.content.Intent; 
import android.os.Build; 
import android.os.Bundle; 
import android.support.annotation.RequiresApi; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.AdapterView; 
import android.widget.ArrayAdapter; 
import android.widget.ImageView; 
import android.widget.RelativeLayout; 
import android.widget.Spinner; 
import android.widget.TextView; 
import android.widget.Toast; 

import java.sql.ResultSet; 
import java.sql.SQLException; 
import java.util.ArrayList; 
import java.util.SortedMap; 

import abtech.waiteriano.com.waitrer.connection_class.ConnectionClass; 
import abtech.waiteriano.com.waitrer.fragments.LVMenuFragment; 
import abtech.waiteriano.com.waitrer.fragments.MenuGridFragment; 
import abtech.waiteriano.com.waitrer.fragments.TablesFragment; 

public class MenuActivity extends AppCompatActivity { 
    private android.support.v7.widget.Toolbar toolbar; 
    private ArrayList<String> Prests_ID; 
    private ArrayList<String> Prests_Name; 
    public static String Prst_ID = "0"; 
    public static long Check_ID = 0; 
    public static int Check_Serial = 0; 
    ImageView listIcon, gridIcon; 
    boolean flag_item_grid = true; 
    RelativeLayout fire, showOrderCart; 
    String[] Menu_List = {"Senegal", "Afrique du Sud", "Kenya", "Ghana", 
      "Liberia", "Burkina Fasso", "Nigeria", "Cameroon", "Uganda", 
      "Tanzania", "Congo", "Malawi", "Zambia"}; 

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_menu); 
     Spinner menu_spinner = (Spinner) findViewById(R.id.spinner); 
     menu_spinner.setAdapter(new MyCustomAdapter(MenuActivity.this, 
       R.layout.spinner_row, Menu_List)); 
     menu_spinner.setOnItemSelectedListener(new MyOnItemSelectedListener()); 

     listIcon = (ImageView) findViewById(R.id.listicon); 
     gridIcon = (ImageView) findViewById(R.id.gridicon); 
     fire = (RelativeLayout) findViewById(R.id.fireID); 
     showOrderCart = (RelativeLayout) findViewById(R.id.cartID); 
     Prests_ID = new ArrayList<String>(); 
     Prests_Name = new ArrayList<String>(); 
     Prests_ID.add("-1"); 
     Prests_Name.add("ALL"); 
     Prst_ID = ConnectionClass.Ret_Col("Select MainCourse From OutLet_Setup Where OutLet_ID = " + ConnectionClass.OutletID); 
     if (Prst_ID.trim() == "") 
      Prst_ID = "0"; 

     String str = "Select ID,Code,Name,Name2 From Presets Where Active = 1 And Rest_ID_Active = 1 AND OutLet_ID_Active = 1 ORDER BY Code"; 
     ResultSet rs = ConnectionClass.Ret_RS(str); 
     try { 
      while (rs.next()) { 
       Prests_ID.add(rs.getString("ID")); 
       Prests_Name.add(rs.getString("Name")); 
      } 
     } catch (SQLException e) { 
      e.printStackTrace(); 
     } 
     toolbar = (Toolbar) findViewById(R.id.toolbar); 
     setSupportActionBar(toolbar); 
     getSupportActionBar().setDisplayShowTitleEnabled(false); 
     Spinner navigationSpinner = new Spinner(getSupportActionBar().getThemedContext()); 
     ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, Prests_Name); 
     navigationSpinner.setAdapter(adapter); 
     toolbar.addView(menu_spinner, 0); 
     int indx = -1; 
     indx = Prests_ID.indexOf(Prst_ID); 
     navigationSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
      @Override 
      public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 
       Prst_ID = Prests_ID.get(position); 
       Toast.makeText(MenuActivity.this, 
         "you selected: " + Prests_ID.get(position) + " " + Prests_Name.get(position), 
         Toast.LENGTH_SHORT).show(); 
       if (flag_item_grid) { 
        FragmentManager fm = getFragmentManager(); 
        fm.beginTransaction().replace(R.id.content_frame, new MenuGridFragment()).commit(); 
       } else { 
        FragmentManager fm = getFragmentManager(); 
        fm.beginTransaction().replace(R.id.content_frame, new LVMenuFragment()).commit(); 
       } 
      } 

      @Override 
      public void onNothingSelected(AdapterView<?> parent) { 

      } 
     }); 
     if (indx != -1) 
      navigationSpinner.setSelection(indx); 

     fire.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       int i = 0; 
       for (String key : TablesFragment.Check_Items.keySet()) { 
        SortedMap<String, String> sm1 = TablesFragment.Check_Items.get(key); 
        int qty = Integer.parseInt(sm1.get("Qty")); 
        if (qty > 0) { 
         i++; 
         double Price = Double.parseDouble(sm1.get("Price")); 
         Price = qty * Price; 
         String st = "insert into ChecksItems (Check_ID,Item_ID,QTY,UnitPrice,TotalPrice,DicountValue,Tax_Value,Adj_Value,NetPrice,Serial,Fired,Fired_Time,Voided,Voided_Time,Voided_Reason,P_On_Check,Complement,Status,IsModifier,Ref_Mod_Item,IsAssimbly,Ref_Ass_Item,Taxable,NoServiceCharge,Num_Fired,Num_Print,Server_ID,P_On_Report,Check_ID_Combine,Round_Check_Fired,Void_Effect_Invn,Promo_ID,Orig_Price,Officer,Comp_Reason_ID,End_Serial_Count,Discount_ID,Disc_Reason_ID,Hold,Hold_Time,Voided_By,Comp_By,Disc_By) values (" + String.valueOf(MenuActivity.Check_ID) + "," + sm1.get("Item_ID").toString() + ",1," + sm1.get("Price").toString() + "," + Price + ",0,0,0," + Price + "," + String.valueOf(i) + ",0,GetDate(),0,GetDate(),0,'" + sm1.get("PrintOnChick").toString() + "',0,'New',0,0,0,0,'" + sm1.get("Taxable").toString() + "','" + sm1.get("NoServiceCharge").toString() + "',0,0,0,'" + sm1.get("PrintOnReport").toString() + "',0,1,0,0," + sm1.get("Price").toString() + ",0,0,0,0,0,0,GetDate(),0,0,0)"; 
         ConnectionClass.executeUpdate(st); 
        } 
       } 
       Toast.makeText(MenuActivity.this, "Fired", Toast.LENGTH_SHORT).show(); 
      } 
     }); 
     showOrderCart.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       Intent i = new Intent(MenuActivity.this, ShowOrderActivity.class); 
       startActivity(i); 
      } 
     }); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     MenuInflater inflater = getMenuInflater(); 
     inflater.inflate(R.menu.iconmenu, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(android.view.MenuItem item) { 
     switch (item.getItemId()) { 
      case R.id.searchicon: 
       // ... 
       return true; 
      case R.id.listicon: 
       FragmentManager fm = getFragmentManager(); 
       fm.beginTransaction().replace(R.id.content_frame, new LVMenuFragment()).commit(); 
       flag_item_grid = false; 
       return true; 
      case R.id.gridicon: 
       // ... 
       fm = getFragmentManager(); 
       fm.beginTransaction().replace(R.id.content_frame, new MenuGridFragment()).commit(); 
       flag_item_grid = true; 
       return true; 
     } 
     return super.onOptionsItemSelected(item); 
    } 

    public class MyCustomAdapter extends ArrayAdapter<String> { 

     public MyCustomAdapter(Context context, int textViewResourceId, 
           String[] objects) { 
      super(context, textViewResourceId, objects); 
      // TODO Auto-generated constructor stub 
     } 
     @Override 
     public View getDropDownView(int position, View convertView, 
            ViewGroup parent) { 
      // TODO Auto-generated method stub 
      return getCustomView(position, convertView, parent); 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      // TODO Auto-generated method stub 
      return getCustomView(position, convertView, parent); 
     } 

     public View getCustomView(int position, View convertView, 
            ViewGroup parent) { 
      // TODO Auto-generated method stub 
      // return super.getView(position, convertView, parent); 

      LayoutInflater inflater = getLayoutInflater(); 
      View row = inflater.inflate(R.layout.spinner_row, parent, false); 
      TextView label = (TextView) row.findViewById(R.id.menu_items); 
      label.setText(Menu_List[position]); 
      return row; 
     } 
    } 
     public class MyOnItemSelectedListener implements AdapterView.OnItemSelectedListener { 

      public void onItemSelected(AdapterView<?> parent, View view, int pos, 
             long id) { 
       Toast.makeText(
         parent.getContext(), 
         "The country is " 
           + parent.getItemAtPosition(pos).toString(), 
         Toast.LENGTH_LONG).show(); 
      } 

      public void onNothingSelected(AdapterView parent) { 
       // Do nothing. 
      } 
     } 

} 

であり、これは私のxmlファイルであるとして、これは

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:orientation="vertical" 
    tools:context="abtech.waiteriano.com.waitrer.MenuActivity"> 
    <android.support.v7.widget.Toolbar 
     android:id="@+id/toolbar" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:background="?attr/colorPrimary" 
     android:minHeight="?attr/actionBarSize" /> 
    <Spinner 
     android:id="@+id/spinner" 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
     android:drawSelectorOnTop="true" 
     android:prompt="@string/ru_prompt" /> 

    <!-- <FrameLayout 
     android:id="@+id/content_frame" 
     android:layout_width="matc 
     h_parent" 
     android:layout_height="wrap_content"></FrameLayout>--> 
    <RelativeLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:gravity="bottom" 
     android:id="@+id/rl1" 
     android:orientation="horizontal" 
     android:weightSum="2"> 
     <FrameLayout 
      android:id="@+id/content_frame" 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:layout_above="@+id/bottom_panel"> 
     </FrameLayout> 

     <LinearLayout 
      android:id="@+id/bottom_panel" 
      android:orientation="horizontal" 
      android:layout_width="match_parent" 
      android:layout_height="40dp" 
      android:weightSum="2" 
      android:layout_alignParentBottom="true"> 
      <RelativeLayout 
       android:id="@+id/fireID" 
       android:layout_width="fill_parent" 
       android:layout_height="50dp" 
       android:layout_weight="1" 
       android:background="#ff6b6b" 
       android:layout_alignParentBottom="true" 
       android:layout_alignParentStart="true"> 
       <ImageView 
        android:id="@+id/imageView1" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:layout_centerHorizontal="true" 
        android:layout_centerVertical="true" 
        android:layout_gravity="center" 
        android:src="@drawable/fire" /> 
      </RelativeLayout> 
      <RelativeLayout 
       android:id="@+id/cartID" 
       android:layout_width="fill_parent" 
       android:layout_height="50dp" 
       android:layout_weight="1" 
       android:background="#6bfff3" 
       android:layout_alignParentBottom="true" 
       android:layout_alignParentStart="true"> 
       <ImageView 
        android:id="@+id/imageCart" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:layout_centerHorizontal="true" 
        android:layout_centerVertical="true" 
        android:layout_gravity="center" 
        android:src="@drawable/shoppingcart" /> 
      </RelativeLayout> 
     </LinearLayout> 
    </RelativeLayout> 
</LinearLayout> 

このエラー

Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first. 

を得ましたあなたのmenu_spinnerはすでにあなたのxmlファイルで宣言されている親ビュー（LinearLayout）が

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

    <TextView 
     android:id="@+id/menu_items" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_marginLeft="5dip" 
     android:layout_marginBottom="10dip" 
     android:layout_marginTop="10dip" 
     android:textColor="#000000" /> 

</LinearLayout> 

Answer 1

if (toolbar.getParent() != null) 
          ((ViewGroup) toolbar.getParent()).removeView(menu_spinner); 

before toolbar.addView（）;

Answer 2

スピナー行.XMLです。アプリがxmlファイルを読み込むと、スピナーが作成され、線形レイアウトに追加されます。したがって、同じスピナーをツールバーに追加しようとすると、エラーが発生します。