如何刪除android

Question

中的選定項目

我有數據庫，並使用simple_list_item_checked佈局顯示列表中的內容。現在我想刪除用戶從該列表中選擇的項目。我該怎麼做？ 這是XML活動：

<ImageButton 
    android:id="@+id/ib_delete" 
    android:layout_width="40dp" 
    android:layout_height="40dp" 
    android:background="@drawable/delete" 
    android:layout_centerHorizontal="true" 
    android:layout_below="@+id/tv_page_mySpace2" 
    android:layout_marginTop="20dp"/> 

<ListView 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:id="@+id/theuserideaslist" 
    android:background="@drawable/brain1" 
    android:layout_below="@id/ib_delete" 
    android:layout_marginTop="20dp"/> 

，這是remove方法，他們告訴我把它放在我開幫手：

public void removeIedas (long id) { 
    String string = String.valueOf(id); 

    database.execSQL("DELETE FROM name WHERE _id = '" + string + "'"); 
} 

，這是我對活動的java類：

final MyOpenHelper myOpenHelper = new MyOpenHelper(getApplicationContext()); 
    final ListView theuserideaslist = (ListView) findViewById(R.id.theuserideaslist); 

    ArrayList<String> n ; 
    n = myOpenHelper.ShowTheUserIdeas(); 
    final ArrayAdapter<String> myadapter = new ArrayAdapter<String> (getApplicationContext() , android.R.layout.simple_list_item_checked , n) ; 
    theuserideaslist.setAdapter(myadapter); 
    theuserideaslist.setChoiceMode(2); 

    final ImageButton ib_delete = (ImageButton) findViewById(R.id.ib_delete); 

    theuserideaslist.setOnItemClickListener(new AdapterView.OnItemClickListener() { 

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

      ib_delete.setOnClickListener(new View.OnClickListener() { 
       @Override 
       public void onClick(View view) { 
        myOpenHelper.removeIedas(id); //create removemethod in database class 

       } 
      }); 

     } 
    }); 

    /* ib_delete.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      theuserideaslist.setOnItemClickListener(new AdapterView.OnItemClickListener() { 

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

        // ArrayList database = null; 
        myOpenHelper.removeIedas(id); //create removemethod in database class 

       } 
      }); 
     } 
    });*/ 

我想要的是：當我點擊ib_delete刪除選中的項目。 對不起，我還是新手。 謝謝。

Answer 1

使用：

listview.setOnItemClickListener(new OnItemClickListener() { 
    @Override 
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 
     database.remove(id); //Create a remove method in your database class 
    } 
}); 

和remove方法：

：

public void remove(long id){ 
    String string = String.valueOf(id); 
    database.execSQL("DELETE FROM favorite WHERE _id = '" + string + "'"); 
} 

從 this stackoverflow question

收集更新10

請勿在按鈕上設置onclick列表器，實際上您可能想要在單擊列表視圖時從列表視圖中刪除項目。

假設你的ListView是爲您的活動的ListView的ID，

這裏：

myDBHelper的類的對象，擴展SQLiteOpenHelper像

public class MyDBHelper extends SQLiteOpenHelper{ 

//codes.. 

    public void DeleteFromDB(String d) { 
    SQLiteDatabase db = getWritableDatabase(); 

    String dm = "\"" + d + "\""; 

    try { 
     db.execSQL("delete from " + db_table + " where taskName=" + dm); 
    } catch (SQLException e) { 
     Toast.makeText(context, e.toString(), Toast.LENGTH_SHORT).show(); 
    } 

    } 
} 

然後在主要使用活動：

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 

     myDBHelper.DeleteFromDB(arrayList.get(position)); 

     } 
    });