Почему мой список не обновляется?

Question

У меня проблема с моим списком. Когда я нажимаю кнопку, он должен добавить элемент в список, но это не так. Я использовал тост, чтобы быть уверенным, что событие onClick для кнопки хорошо. Может кто-нибудь мне помочь ? Это код java фрагмента.

package com.wordpress.softwarebycs.i_cseditor; 

import android.app.ActionBar; 
import android.app.Activity; 
import android.content.Context; 
import android.graphics.Color; 
import android.os.Bundle; 
import android.support.annotation.Nullable; 
import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentActivity; 
import android.text.Layout; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.webkit.WebView; 
import android.widget.AdapterView; 
import android.widget.ArrayAdapter; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.LinearLayout; 
import android.widget.ListView; 
import android.widget.Spinner; 
import android.widget.TabHost; 
import android.widget.TabWidget; 
import android.widget.TextView; 
import android.widget.Toast; 

import java.io.BufferedReader; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.util.ArrayList; 

/** 
* Created by Cosmin on 11.04.2015. 
*/ 
public class code_Fragment extends Fragment implements AdapterView.OnItemSelectedListener{ 


    View rootview; 
    WebView previewBrowser; 
    EditText codebox,fname; 
    Button save_btn; 
    Spinner spinner; 

    ArrayList<String> list = new ArrayList<String>(); 
    ArrayAdapter<String> list_adapter; 
    ListView projects; 
    @Nullable 
    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstance) 
    { 



     rootview = inflater.inflate(R.layout.code_layout,container, false); 
     previewBrowser = (WebView)rootview.findViewById(R.id.previewBrowser); 
     codebox= (EditText)rootview.findViewById(R.id.codebox); 
     projects=(ListView)rootview.findViewById(R.id.projectsListView); 

     list_adapter=new ArrayAdapter<String>(rootview.getContext(), android.R.layout.simple_list_item_1, list); 
     projects.setAdapter(list_adapter); 
     list.clear(); 


     save_btn=(Button)rootview.findViewById(R.id.save_btn); 
     save_btn.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       writeFile(); 

      } 

     }); 

     fname=(EditText)rootview.findViewById(R.id.fname); 

     spinner= (Spinner)rootview.findViewById(R.id.spinner); 


     ArrayAdapter adapter = ArrayAdapter.createFromResource(rootview.getContext(),R.array.spinner_items,android.R.layout.simple_spinner_dropdown_item); 
     spinner.setAdapter(adapter); 



     final TabHost tabHost=(TabHost)rootview.findViewById(R.id.tabHost); 
     tabHost.setup(); 
     tabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() { 
      @Override 
      public void onTabChanged(String tabId) { 
       String file="i_C_s_editor_temp_file_ne_trebuie_un_nume_lung_tare_de_tot.html"; 
       try { 
        FileOutputStream fos = getActivity().openFileOutput(file, Context.MODE_PRIVATE); 
        fos.write(codebox.getText().toString().getBytes()); 
        fos.close(); 
       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
       previewBrowser.loadUrl("file:///data/data/com.wordpress.softwarebycs.i_cseditor/files/"+file); 

      } 
     }); 
     TabHost.TabSpec spec1=tabHost.newTabSpec("Code"); 
     spec1.setContent(R.id.codeTab); 
     spec1.setIndicator("Code"); 

     TabHost.TabSpec spec2=tabHost.newTabSpec("Preview"); 
     spec2.setContent(R.id.previewTab); 
     spec2.setIndicator("Preview"); 

     TabHost.TabSpec spec3=tabHost.newTabSpec("File"); 
     spec3.setContent(R.id.fileTab); 
     spec3.setIndicator("File"); 

     tabHost.addTab(spec1); 
     tabHost.addTab(spec2); 
     tabHost.addTab(spec3); 


     for(int i=0;i<tabHost.getTabWidget().getChildCount();i++) 
     { 
      TextView tv = (TextView) tabHost.getTabWidget().getChildAt(i).findViewById(android.R.id.title); 
      tv.setTextColor(Color.parseColor("#ffe0e0e0")); 
     } 


     projects.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
      public void onItemClick(AdapterView<?> parentAdapter, View view, int position, long id) { 
       TextView clickedView = (TextView) view; 
       readFile(clickedView.getText().toString()); 
       //tabHost.setCurrentTab(0); 
      } 
     }); 

     return rootview; 

    } 

    public void writeFile() 
    { 
     String FILE_NAME=fname.getText().toString()+spinner.getSelectedItem().toString(); 
     try { 
      FileOutputStream fos = getActivity().openFileOutput(FILE_NAME, Context.MODE_PRIVATE); 

      fos.write(codebox.getText().toString().getBytes()); 
      list.add(FILE_NAME); 
      Toast toast = Toast.makeText(rootview.getContext(), 
        "File saved!", 
        Toast.LENGTH_SHORT); 

      toast.show(); 
      fos.close(); 
     } catch (Exception e) { 
      e.printStackTrace(); 
     } 
    } 


    @Override 
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 

    } 

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

    } 

    public void actionStopped(){ 
     try { 
      FileOutputStream fos = getActivity().openFileOutput("cfg2.txt", Context.MODE_PRIVATE); 
      Integer k; 
      for(k=0;k<list.size();k++) 
      {fos.write(list.get(k).toString().getBytes()); 
       fos.write(System.getProperty("line.separator").getBytes());} 
      fos.close(); 
     } catch (Exception e) { 
      e.printStackTrace(); 
     } 

    } 



    public void actionResummed() { 
     list.clear(); 
     try { 
      BufferedReader bReader = new BufferedReader(new InputStreamReader(getActivity().openFileInput("cfg2.txt"))); 
      String line; 
      while ((line = bReader.readLine()) != null) { 
       list.add(line); 
      } 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
    } 

    @Override 
    public void onResume() { 
     super.onResume(); 
     actionResummed(); 
    } 

    @Override 
    public void onPause() { 
     super.onPause(); 
     actionStopped(); 
    } 

    public void readFile(String path) 
    { 

     codebox.setText(""); 
     try { 
      BufferedReader bReader = new BufferedReader(new InputStreamReader(getActivity().openFileInput(path))); 
      String line; 
      while ((line = bReader.readLine()) != null) { 
       codebox.append(line + "\n"); 
      } 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
    } 


} 

И это XML-фрагмента

<?xml version="1.0" encoding="utf-8"?> 
<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" android:paddingLeft="@dimen/activity_horizontal_margin" 
    android:paddingRight="@dimen/activity_horizontal_margin" 
    android:paddingTop="@dimen/activity_vertical_margin" 
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity" 
    android:background="#ff666666"> 

    <TabHost 
     android:layout_width="fill_parent" 
     android:layout_height="fill_parent" 
     android:id="@+id/tabHost" 
     android:layout_alignParentTop="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentStart="true"> 

     <LinearLayout 
      android:layout_width="fill_parent" 
      android:layout_height="fill_parent" 
      android:orientation="vertical" 
      android:background="#ff8a3e6b"> 

      <TabWidget 
       android:id="@android:id/tabs" 
       android:layout_width="fill_parent" 
       android:layout_height="wrap_content"></TabWidget> 

      <FrameLayout 
       android:id="@android:id/tabcontent" 
       android:layout_width="fill_parent" 
       android:layout_height="fill_parent"> 

      <LinearLayout 
        android:id="@+id/codeTab" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent" 
        android:orientation="vertical"> 

        <EditText 
         android:layout_width="fill_parent" 
         android:layout_height="fill_parent" 
         android:inputType="textMultiLine" 
         android:ems="10" 
         android:id="@+id/codebox" 
         android:gravity="top|left" 
         android:background="#ffffffff" 
         android:scrollbars="vertical|horizontal"/> 
       </LinearLayout> 

      <LinearLayout 
        android:id="@+id/previewTab" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent" 
        android:orientation="vertical"> 
        <WebView 
         android:layout_width="fill_parent" 
         android:layout_height="fill_parent" 
         android:id="@+id/previewBrowser" 
         android:scrollbars="vertical|horizontal" 
         ></WebView> 

       </LinearLayout> 
<!--fileTab--> 
      <LinearLayout 
        android:id="@+id/fileTab" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent" 
        android:background="#ff666666" 
        android:orientation="vertical" 
         > 

        <LinearLayout 
         android:orientation="vertical" 
         android:layout_width="fill_parent" 
         android:layout_height="wrap_content" 
         android:id="@+id/linearLayout" 
         android:layout_marginBottom="20dp"> 

         <TextView 
          android:layout_width="wrap_content" 
          android:layout_height="wrap_content" 
          android:textAppearance="?android:attr/textAppearanceLarge" 
          android:text="File&apos;s Name" 
          android:id="@+id/textView2" 
          android:layout_gravity="center_horizontal" 
          android:textColor="#ffe0e0e0" 
          android:layout_below="@+id/linearLayout" 
          android:layout_centerHorizontal="true" 
          android:layout_marginTop="20dp" /> 
        </LinearLayout> 

        <LinearLayout 
         android:orientation="horizontal" 
         android:layout_width="fill_parent" 
         android:layout_height="wrap_content" 
         android:layout_below="@+id/linearLayout" 
         android:layout_centerHorizontal="true" 
         android:id="@+id/linearLayout2"> 

         <EditText 
          android:layout_width="237dp" 
          android:layout_height="41dp" 
          android:id="@+id/fname" 
          android:layout_marginTop="10dp" 
          android:background="#ff8a3e6b" 
          android:textColor="#ffe0e0e0" /> 

         <Spinner 
          android:layout_width="fill_parent" 
          android:layout_height="41dp" 
          android:id="@+id/spinner" 
          android:background="#ff8a3e6b" 
          android:layout_marginTop="9dp" 
          /> 
        </LinearLayout> 

        <LinearLayout 
         android:orientation="vertical" 
         android:layout_width="fill_parent" 
         android:layout_height="wrap_content" 
         android:layout_below="@+id/linearLayout2" 
         android:layout_centerHorizontal="true" 
         android:id="@+id/linearLayout3"> 


         <Button 
          android:layout_width="wrap_content" 
          android:layout_height="wrap_content" 
          android:text="Save File" 
          android:id="@+id/save_btn" 
          android:layout_gravity="center" 
          android:layout_marginTop="10dp" 
          android:background="#ff8a3e6b" 
          android:textColor="#ffe0e0e0" 
         /> 
        </LinearLayout> 
<!-- separator--> 
       <TextView 
        android:layout_width="fill_parent" 
        android:layout_height="1dp" 
        android:id="@+id/separator" 
        android:background="#ff8a3e6b" 
        android:layout_marginTop="5dp" /> 
       <!--open file --> 
       <LinearLayout 
        android:orientation="vertical" 
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content" 
        android:layout_below="@+id/separator" 
        android:layout_centerHorizontal="true" 
        android:id="@+id/linearLayout4"> 

        <TextView 
         android:paddingTop="20dp" 
         android:paddingBottom="20dp" 
         android:layout_width="wrap_content" 
         android:layout_height="wrap_content" 
         android:id="@+id/text2" 
         android:textSize="25dp" 
         android:text="Select file to open!" 
         android:layout_gravity="top|center" 
         /> 

        <ListView 
         android:layout_width="fill_parent" 
         android:layout_below="@+id/text2" 
         android:layout_height="fill_parent" 
         android:id="@+id/projectsListView" 
         android:scrollbars="vertical|horizontal" 
         android:background="#ff8a3e6b"> 
        </ListView> 
       </LinearLayout> 
      </LinearLayout> 
      </FrameLayout> 
     </LinearLayout> 
    </TabHost> 

</RelativeLayout> 

Answer 1

Чтобы обновить ListView, вы должны уведомить его, я не вижу способа уведомления в методе щелчка

Добавить ниже код в

save_btn.setOnClickListener //Method after calling to writeFile() Method 

    list_adapter.notifyDataSetChanged();