如何使用列表視圖中的按鈕刪除列表視圖項目

Question

我希望能夠通過單擊列表視圖上的按鈕從列表視圖中移除列表項目。

所以我認爲正確的道路是爲按鈕設置OnClickListener。問題是，我不知道如何從AddSpeakerActivity.languages實際刪除語言，以及從ListView中刪除關聯的項目。我怎樣才能做到這一點？謝謝！

這裏是我的列表項佈局：

<?xml version="1.0" encoding="utf-8"?>           
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"   
     android:layout_width="fill_parent"          
     android:layout_height="fill_parent"          
     android:orientation="horizontal" android:baselineAligned="false" >  
    <TextView android:textAppearance="?android:attr/textAppearanceMedium"   
      android:layout_height="wrap_content"         
      android:text=""              
      android:layout_width="0dp"           
      android:layout_weight="1"           
      android:layout_gravity="center_vertical"        
      android:id="@+id/recordingName"/>         
    <ImageButton android:src="@drawable/cancel_32"        
      android:layout_gravity="center"          
      android:padding="5dip"            
      android:layout_margin="10dip"          
      android:scaleType="centerInside"          
      android:layout_width="60dip"           
      android:layout_height="60dip"          
      android:id="@+id/removeButton"/>          
</LinearLayout> 

這裏是有問題的活動：

package org.lp20.aikuma.ui;              

import android.app.ListActivity;             
import android.content.Intent;             
import android.os.Bundle;              
import android.util.Log;               
import android.view.View;              
import android.widget.ArrayAdapter;            
import java.io.IOException;              
import java.util.ArrayList;              
import java.util.List;               
import org.lp20.aikuma.model.Language;           
import org.lp20.aikuma.model.Recording;           
import org.lp20.aikuma.R;              
import org.lp20.aikuma.util.FileIO;            

public class AddSpeakerActivity extends ListActivity {       

    @Override                 
    public void onCreate(Bundle savedInstanceState) {       
     super.onCreate(savedInstanceState);          
     setContentView(R.layout.add_speaker);         
     languages = FileIO.readDefaultLanguages();        
    }                   

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

     ArrayAdapter<Language> adapter =           
       new SpeakerLanguagesArrayAdapter(this, languages);    
     setListAdapter(adapter);             
    }                   

    public void onAddLanguageButton(View view) {         
     Intent intent = new Intent(this, LanguageFilterList.class);    
     startActivityForResult(intent, SELECT_LANGUAGE);       
    }                   

    protected void onActivityResult(int requestCode, int resultCode, Intent  
      intent) {               
     if (requestCode == SELECT_LANGUAGE) {         
      if (resultCode == RESULT_OK) {          
       languages.add((Language)           
         intent.getParcelableExtra("language"));     
       Log.i("langs", "langs");           
      }                 
     }                  
    }                   

    static final int SELECT_LANGUAGE = 0;          
    private List<Language> languages = new ArrayList<Language>();    
} 

這裏是陣列適配器：

package org.lp20.aikuma.ui;              

import android.content.Context;             
import android.util.Log;               
import android.view.LayoutInflater;            
import android.view.View;              
import android.view.View.OnClickListener;          
import android.view.ViewGroup;             
import android.widget.ArrayAdapter;            
import android.widget.ImageButton;            
import android.widget.TextView;             
import java.util.List;               
import org.lp20.aikuma.model.Language;           
import org.lp20.aikuma.R;              

public class SpeakerLanguagesArrayAdapter extends ArrayAdapter<Language> {   
    public SpeakerLanguagesArrayAdapter(Context context, List<Language>   
      languages) {               
     super(context, listItemLayout, languages);        
     inflater = (LayoutInflater)            
       context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);   
    }                   

    @Override                 
    public View getView(int position, View _, ViewGroup parent) {    
     Log.i("langs", "getView");            
     View recordingView =              
       (View) inflater.inflate(listItemLayout, parent, false);   
     final Language language = getItem(position);        
     TextView recordingNameView =            
       (TextView) recordingView.findViewById(R.id.recordingName);   
     ImageButton removeLanguageButton =          
       (ImageButton) recordingView.findViewById(R.id.removeButton);  
     removeLanguageButton.setOnClickListener(new OnClickListener() {   
      public void onClick(View view) {          
       Log.i("langs", "language: " + language);       
      }                 
     });                  

     recordingNameView.setText(language.toString());       
     return recordingView;             
    }                   

    private static final int listItemLayout =         
      R.layout.speakerlanguages_list_item;         
    private LayoutInflater inflater;            

} 

Answer 1

您需要刪除從您的活動傳遞到您的列表中的項目，然後刷新ui。

removeLanguageButton.setOnClickListener(new OnClickListener() {   
    public void onClick(View view) {          
     Log.i("langs", "language: " + language);       
     languages.remove(language); 
     notifyDataSetChange(); 
     //here you need to notify the activity list to ensure the data is always right. 
    }                 
});