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Android 在CountryList类中再添加一个文本框不显示值

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Android 在CountryList类中再添加一个文本框不显示值,android,Android,这是我的最后一篇文章，请告诉我如何在代码中再添加一个文本框？？？我添加了新的文本框private EditText LocationEd；但是，当我保存数据时，没有任何值显示此代码中有什么错误？我从这个url复制这个代码 AddEditCountry public class AddEditCountry extends Activity { private long rowID; private EditText nameEt; private EditText capEt; pr

这是我的最后一篇文章，请告诉我如何在代码中再添加一个文本框？？？我添加了新的文本框private EditText LocationEd；但是，当我保存数据时，没有任何值显示此代码中有什么错误？我从这个url复制这个代码

AddEditCountry

public class AddEditCountry extends Activity {

 private long rowID; 
 private EditText nameEt;
 private EditText capEt;
 private EditText codeEt;

 private EditText LocationEd;

   @Override
   public void onCreate(Bundle savedInstanceState) 
   {
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.add_country);

      nameEt = (EditText) findViewById(R.id.nameEdit);
      capEt = (EditText) findViewById(R.id.capEdit);
      codeEt = (EditText) findViewById(R.id.codeEdit);

      LocationEd = (EditText) findViewById(R.id.LocationEdit);

      Bundle extras = getIntent().getExtras(); 

      if (extras != null)
      {
         rowID = extras.getLong("row_id");
         nameEt.setText(extras.getString("name"));  
         capEt.setText(extras.getString("cap"));  
         codeEt.setText(extras.getString("code"));  
         LocationEd.setText(extras.getString("Location"));  
      }

      Button saveButton =(Button) findViewById(R.id.saveBtn);
      saveButton.setOnClickListener(new OnClickListener() {

          public void onClick(View v) 
          {
             if (nameEt.getText().length() != 0)
             {
                AsyncTask<Object, Object, Object> saveContactTask = 
                   new AsyncTask<Object, Object, Object>() 
                   {
                      @Override
                      protected Object doInBackground(Object... params) 
                      {
                         saveContact();
                         return null;
                      }

                      @Override
                      protected void onPostExecute(Object result) 
                      {
                         finish();
                      }
                   }; 

                saveContactTask.execute((Object[]) null); 
             }

             else
             {
                AlertDialog.Builder alert = new  
 AlertDialog.Builder(AddEditCountry.this);
                alert.setTitle(R.string.errorTitle); 
                alert.setMessage(R.string.errorMessage);
                alert.setPositiveButton(R.string.errorButton, null); 
                alert.show();
             }
          } 
     });
   }

   private void saveContact() 
   {
      DatabaseConnector dbConnector = new DatabaseConnector(this);

      if (getIntent().getExtras() == null)
      {
          dbConnector.insertContact(nameEt.getText().toString(),
                  capEt.getText().toString(),
                  codeEt.getText().toString(),   
  LocationEd.getText().toString());
      }
      else
      {
         dbConnector.updateContact(rowID,
            nameEt.getText().toString(),
            capEt.getText().toString(), 
            codeEt.getText().toString(), 
            LocationEd.getText().toString());
      }
   }
}         

 public class ViewCountry extends Activity {

   private long rowID;
   private TextView nameTv;
   private TextView capTv;
   private TextView codeTv; 


   private TextView Locationlb; 

   @Override
   public void onCreate(Bundle savedInstanceState) 
   {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.view_country);

      setUpViews();
      Bundle extras = getIntent().getExtras();
      rowID = extras.getLong(CountryList.ROW_ID); 
   }

   private void setUpViews() {
       nameTv = (TextView) findViewById(R.id.nameText);
       capTv = (TextView) findViewById(R.id.capText);
       codeTv = (TextView) findViewById(R.id.codeText);

       Locationlb = (TextView) findViewById(R.id.Location_lbl);
   }

   @Override
   protected void onResume()
   {
      super.onResume();
      new LoadContacts().execute(rowID);
   } 

   private class LoadContacts extends AsyncTask<Long, Object, Cursor> 
   {
      DatabaseConnector dbConnector = new DatabaseConnector(ViewCountry.this);

      @Override
      protected Cursor doInBackground(Long... params)
      {
         dbConnector.open();
         return dbConnector.getOneContact(params[0]);
      } 

      @Override
      protected void onPostExecute(Cursor result)
      {
         super.onPostExecute(result);

         result.moveToFirst();
         // get the column index for each data item
         int nameIndex = result.getColumnIndex("name");
         int capIndex = result.getColumnIndex("cap");
         int codeIndex = result.getColumnIndex("code");

         int LocationIndex = result.getColumnIndex("Location");

         nameTv.setText(result.getString(nameIndex));
         capTv.setText(result.getString(capIndex));
         codeTv.setText(result.getString(codeIndex));
         Locationlb.setText(result.getString(LocationIndex));

         result.close();
         dbConnector.close();
      }
   } 


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

   @Override
   public boolean onOptionsItemSelected(MenuItem item) 
   {
      switch (item.getItemId())
      {
         case R.id.editItem:
            Intent addEditContact =
               new Intent(this, AddEditCountry.class);

            addEditContact.putExtra(CountryList.ROW_ID, rowID);
            addEditContact.putExtra("name", nameTv.getText());
            addEditContact.putExtra("cap", capTv.getText());
            addEditContact.putExtra("code", codeTv.getText());

            addEditContact.putExtra("Location", Locationlb.getText());
            startActivity(addEditContact); 
            return true;

         case R.id.deleteItem:
            deleteContact();
            return true;

         default:
            return super.onOptionsItemSelected(item);
      } 
   }

   private void deleteContact()
   {

      AlertDialog.Builder alert = new AlertDialog.Builder(ViewCountry.this);

      alert.setTitle(R.string.confirmTitle); 
      alert.setMessage(R.string.confirmMessage); 

      alert.setPositiveButton(R.string.delete_btn,
         new DialogInterface.OnClickListener()
         {
            public void onClick(DialogInterface dialog, int button)
            {
               final DatabaseConnector dbConnector = 
                  new DatabaseConnector(ViewCountry.this);

               AsyncTask<Long, Object, Object> deleteTask =
                  new AsyncTask<Long, Object, Object>()
                  {
                     @Override
                     protected Object doInBackground(Long... params)
                     {
                        dbConnector.deleteContact(params[0]); 
                        return null;
                     } 

                     @Override
                     protected void onPostExecute(Object result)
                     {
                        finish(); 
                     }
                  };

               deleteTask.execute(new Long[] { rowID });               
            }
         }
      );

      alert.setNegativeButton(R.string.cancel_btn, null).show();
   }
}
数据库OpenHelper

  public class DatabaseConnector {

private static final String DB_NAME = "WorldCountries";
private SQLiteDatabase database;
private DatabaseOpenHelper dbOpenHelper;

public DatabaseConnector(Context context) {
    dbOpenHelper = new DatabaseOpenHelper(context, DB_NAME, null, 1);
}

   public void open() throws SQLException 
   {
      //open database in reading/writing mode
      database = dbOpenHelper.getWritableDatabase();
   } 

   public void close() 
   {
      if (database != null)
         database.close();
   }       

   public void insertContact(String name, String cap, String code, String  
     LocationEd) 
           {
              ContentValues newCon = new ContentValues();
              newCon.put("name", name);
              newCon.put("cap", cap);
              newCon.put("code", code);

              newCon.put("Location",LocationEd);

              open();
              database.insert("country", null, newCon);
              close();
           }


           public void updateContact(long id, String name, String  
     cap,String code,String LocationEd) 
           {
              ContentValues editCon = new ContentValues();
              editCon.put("name", name);
              editCon.put("cap", cap);
              editCon.put("code", code);
              editCon.put("Location", LocationEd);

              open();
              database.update("country", editCon, "_id=" + id, null);
              close();
           }


           public Cursor getAllContacts() 
           {
              return database.query("country", new String[] {"_id",  
    "name"}, 
                 null, null, null, null, "name");
           }

           public Cursor getOneContact(long id) 
           {
              return database.query("country", null, "_id=" + id, null,  
  null, null, null);
           }

           public void deleteContact(long id) 
           {
              open(); 
              database.delete("country", "_id=" + id, null);
              close();
           }
   }

 public class DatabaseOpenHelper extends SQLiteOpenHelper {

public DatabaseOpenHelper(Context context, String name,
        CursorFactory factory, int version) {
    super(context, name, factory, version);
}

@Override
public void onCreate(SQLiteDatabase db) {
    String createQuery = "CREATE TABLE country (_id integer primary key  
    autoincrement,name,cap,code,Location);";                 
    db.execSQL(createQuery);        
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

  }
查看国家/地区

public class AddEditCountry extends Activity {

 private long rowID; 
 private EditText nameEt;
 private EditText capEt;
 private EditText codeEt;

 private EditText LocationEd;

   @Override
   public void onCreate(Bundle savedInstanceState) 
   {
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.add_country);

      nameEt = (EditText) findViewById(R.id.nameEdit);
      capEt = (EditText) findViewById(R.id.capEdit);
      codeEt = (EditText) findViewById(R.id.codeEdit);

      LocationEd = (EditText) findViewById(R.id.LocationEdit);

      Bundle extras = getIntent().getExtras(); 

      if (extras != null)
      {
         rowID = extras.getLong("row_id");
         nameEt.setText(extras.getString("name"));  
         capEt.setText(extras.getString("cap"));  
         codeEt.setText(extras.getString("code"));  
         LocationEd.setText(extras.getString("Location"));  
      }

      Button saveButton =(Button) findViewById(R.id.saveBtn);
      saveButton.setOnClickListener(new OnClickListener() {

          public void onClick(View v) 
          {
             if (nameEt.getText().length() != 0)
             {
                AsyncTask<Object, Object, Object> saveContactTask = 
                   new AsyncTask<Object, Object, Object>() 
                   {
                      @Override
                      protected Object doInBackground(Object... params) 
                      {
                         saveContact();
                         return null;
                      }

                      @Override
                      protected void onPostExecute(Object result) 
                      {
                         finish();
                      }
                   }; 

                saveContactTask.execute((Object[]) null); 
             }

             else
             {
                AlertDialog.Builder alert = new  
 AlertDialog.Builder(AddEditCountry.this);
                alert.setTitle(R.string.errorTitle); 
                alert.setMessage(R.string.errorMessage);
                alert.setPositiveButton(R.string.errorButton, null); 
                alert.show();
             }
          } 
     });
   }

   private void saveContact() 
   {
      DatabaseConnector dbConnector = new DatabaseConnector(this);

      if (getIntent().getExtras() == null)
      {
          dbConnector.insertContact(nameEt.getText().toString(),
                  capEt.getText().toString(),
                  codeEt.getText().toString(),   
  LocationEd.getText().toString());
      }
      else
      {
         dbConnector.updateContact(rowID,
            nameEt.getText().toString(),
            capEt.getText().toString(), 
            codeEt.getText().toString(), 
            LocationEd.getText().toString());
      }
   }
}         

 public class ViewCountry extends Activity {

   private long rowID;
   private TextView nameTv;
   private TextView capTv;
   private TextView codeTv; 


   private TextView Locationlb; 

   @Override
   public void onCreate(Bundle savedInstanceState) 
   {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.view_country);

      setUpViews();
      Bundle extras = getIntent().getExtras();
      rowID = extras.getLong(CountryList.ROW_ID); 
   }

   private void setUpViews() {
       nameTv = (TextView) findViewById(R.id.nameText);
       capTv = (TextView) findViewById(R.id.capText);
       codeTv = (TextView) findViewById(R.id.codeText);

       Locationlb = (TextView) findViewById(R.id.Location_lbl);
   }

   @Override
   protected void onResume()
   {
      super.onResume();
      new LoadContacts().execute(rowID);
   } 

   private class LoadContacts extends AsyncTask<Long, Object, Cursor> 
   {
      DatabaseConnector dbConnector = new DatabaseConnector(ViewCountry.this);

      @Override
      protected Cursor doInBackground(Long... params)
      {
         dbConnector.open();
         return dbConnector.getOneContact(params[0]);
      } 

      @Override
      protected void onPostExecute(Cursor result)
      {
         super.onPostExecute(result);

         result.moveToFirst();
         // get the column index for each data item
         int nameIndex = result.getColumnIndex("name");
         int capIndex = result.getColumnIndex("cap");
         int codeIndex = result.getColumnIndex("code");

         int LocationIndex = result.getColumnIndex("Location");

         nameTv.setText(result.getString(nameIndex));
         capTv.setText(result.getString(capIndex));
         codeTv.setText(result.getString(codeIndex));
         Locationlb.setText(result.getString(LocationIndex));

         result.close();
         dbConnector.close();
      }
   } 


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

   @Override
   public boolean onOptionsItemSelected(MenuItem item) 
   {
      switch (item.getItemId())
      {
         case R.id.editItem:
            Intent addEditContact =
               new Intent(this, AddEditCountry.class);

            addEditContact.putExtra(CountryList.ROW_ID, rowID);
            addEditContact.putExtra("name", nameTv.getText());
            addEditContact.putExtra("cap", capTv.getText());
            addEditContact.putExtra("code", codeTv.getText());

            addEditContact.putExtra("Location", Locationlb.getText());
            startActivity(addEditContact); 
            return true;

         case R.id.deleteItem:
            deleteContact();
            return true;

         default:
            return super.onOptionsItemSelected(item);
      } 
   }

   private void deleteContact()
   {

      AlertDialog.Builder alert = new AlertDialog.Builder(ViewCountry.this);

      alert.setTitle(R.string.confirmTitle); 
      alert.setMessage(R.string.confirmMessage); 

      alert.setPositiveButton(R.string.delete_btn,
         new DialogInterface.OnClickListener()
         {
            public void onClick(DialogInterface dialog, int button)
            {
               final DatabaseConnector dbConnector = 
                  new DatabaseConnector(ViewCountry.this);

               AsyncTask<Long, Object, Object> deleteTask =
                  new AsyncTask<Long, Object, Object>()
                  {
                     @Override
                     protected Object doInBackground(Long... params)
                     {
                        dbConnector.deleteContact(params[0]); 
                        return null;
                     } 

                     @Override
                     protected void onPostExecute(Object result)
                     {
                        finish(); 
                     }
                  };

               deleteTask.execute(new Long[] { rowID });               
            }
         }
      );

      alert.setNegativeButton(R.string.cancel_btn, null).show();
   }
}

公共类ViewCountry扩展活动{
私人长罗威德；
私有文本视图名称电视；
私有文本视图capTv；
私有文本视图代码电视；
私有文本视图位置LB；
@凌驾
创建时的公共void（Bundle savedInstanceState）
{
super.onCreate（savedInstanceState）；
setContentView（R.layout.view_country）；
setupview（）；
Bundle extras=getIntent（）.getExtras（）；
rowID=extras.getLong（CountryList.ROW\u ID）；
}
私有void setUpViews（）{
nameTv=（TextView）findviewbyd（R.id.nameText）；
capTv=（文本视图）findViewById（R.id.capText）；
codeTv=（TextView）findviewbyd（R.id.codeText）；
Locationlb=（TextView）findViewById（R.id.Location\u lbl）；
}
@凌驾
受保护的void onResume（）
{
super.onResume（）；
新建LoadContacts（）.execute（rowID）；
} 
私有类LoadContacts扩展异步任务
{
DatabaseConnector dbConnector=新的DatabaseConnector（ViewCountry.this）；
@凌驾
受保护的光标背景（长…参数）
{
dbConnector.open（）；
返回dbConnector.getOneContact（参数[0]）；
} 
@凌驾
受保护的void onPostExecute（游标结果）
{
super.onPostExecute（结果）；
result.moveToFirst（）；
//获取每个数据项的列索引
int nameIndex=result.getColumnIndex（“名称”）；
int capIndex=result.getColumnIndex（“cap”）；
int codeIndex=result.getColumnIndex（“代码”）；
int LocationIndex=result.getColumnIndex（“位置”）；
nameTv.setText（result.getString（nameIndex））；
setText（result.getString（capIndex））；
setText（result.getString（codeIndex））；
Locationlb.setText（result.getString（LocationIndex））；
result.close（）；
dbConnector.close（）；
}
} 
@凌驾
公共布尔onCreateOptions菜单（菜单）
{
super.onCreateOptions菜单（菜单）；
MenuInflater充气机=getMenuInflater（）；
充气器。充气（右菜单。查看国家菜单，菜单）；
返回true；
}
@凌驾
公共布尔值onOptionsItemSelected（菜单项项）
{
开关（item.getItemId（））
{
案例R.id.editItem：
意向书=
新的意图（此，添加了Country.class）；
addEditContact.putExtra（CountryList.ROW_ID，rowID）；
addEditContact.putExtra（“name”，nameTv.getText（））；
addEditContact.putExtra（“cap”，capTv.getText（））；
addEditContact.putExtra（“code”，codeTv.getText（））；
addEditContact.putExtra（“位置”，Locationlb.getText（））；
startActivity（addEditContact）；
返回true；
案例R.id.deleteItem：
deleteContact（）；
返回true；
违约：
返回super.onOptionsItemSelected（项目）；
} 
}
私有void deleteContact（）
{
AlertDialog.Builder alert=新建AlertDialog.Builder（ViewCountry.this）；
alert.setTitle（R.string.confirmTitle）；
alert.setMessage（R.string.confirmMessage）；
alert.setPositiveButton（R.string.delete_btn，
新建DialogInterface.OnClickListener（）
{
公共void onClick（对话框接口对话框，int按钮）
{
最终数据库连接器dbConnector=
新的数据库连接器（ViewCountry.this）；
异步任务删除任务=
新建异步任务（）
{
@凌驾
受保护对象doInBackground（长…参数）
{
dbConnector.deleteContact（参数[0]）；
返回null；
} 
@凌驾
受保护的void onPostExecute（对象结果）
{
完成（）；
}
};
deleteTask.execute（新的长[]{rowID}）；
}
}
);
alert.setNegativeButton（R.string.cancel_btn，null）.show（）；
}
}
查看您的代码，似乎一切都是正确的。您是否在更改数据库后卸载并重新安装了应用程序？数据库创建语句仅在第一次初始化数据库时调用，因此如果不清除数据或卸载并重新安装应用程序，则新的
位置
列不存在。

如果删除了
编辑文本位置编辑文本然后开始工作？您确定捆绑包包含键为
“Location”
的字符串对象吗？我猜当在另一个活动中单击列表项时，
AddEditActivity
就会启动。你也修改了那个代码吗？是的，正在编写，我添加了定位编辑文本框，所以不起作用，那么我该怎么办？实际上，在所有代码中，有3个editfield，我又添加了一个，因此我如何管理它？？？@ρцσѕρєK在
doInBackground
中使用
EditText.getText（）
，没有什么错，因为您没有更新UI<另一方面，code>EditText.setText（）
不起作用。你是说删除手机内存？