Android保存按钮不保存到数据库中

Question

我在应用程序中有一个保存按钮，它似乎并没有保存它应该保存的内容。

这是功能按钮呼叫：

public void newsave (View rootView) { 
    final Dbhandler dbHandler = new Dbhandler(this.getActivity()); 

    final String distance = (result2.getText().toString()); 


    AlertDialog.Builder builder = new AlertDialog.Builder(this.getActivity()); 
    builder.setTitle("Description"); 
    final AlertDialog dialog =builder.create(); 



         // Set up the input 
         final EditText input = new EditText(this.getActivity()); 
         input.setOnFocusChangeListener(new 
View.OnFocusChangeListener() { 
         @Override 
         public void onFocusChange(View v, boolean hasFocus) { 
          if (hasFocus) { 
           dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE); 
          } 
         } 
        }); 
         // Specify the type of input expected; this, for example, sets the input as a password, and will mask the text 
         input.setInputType(InputType.TYPE_CLASS_TEXT); 
         builder.setView(input); 

         // Set up the buttons 
         builder.setPositiveButton("Save", new DialogInterface.OnClickListener() { 
          @Override 
          public void onClick(DialogInterface dialog, int which) { 
           m_Text = input.getText().toString(); 

           String ddesc = m_Text; 
           //saveDistance distances = new saveDistance(ddesc,distance); 
           try { 
            dbHandler.addDistances(1,ddesc, distance); 
            Toast.makeText(getActivity(), "Save Successful", Toast.LENGTH_LONG).show(); 
           } catch (Exception e) { 
            Toast.makeText(getActivity(), e.toString(), Toast.LENGTH_LONG).show(); 
           } 

          } 
         }); 

    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { 
          @Override 
          public void onClick(DialogInterface dialog, int which) { 
           dialog.cancel(); 
          } 
         }); 

         builder.show(); 

这是我的数据库处理类

package com.spydotechcorps.hwfar.database; 

import android.content.ContentResolver; 
import android.content.ContentValues; 
import android.content.Context; 
import android.database.Cursor; 
import android.database.sqlite.SQLiteDatabase; 
import android.database.sqlite.SQLiteOpenHelper; 

import com.spydotechcorps.hwfar.provider.MyContentProvider; 

/** 
* Created by INGENIO on 3/8/2015. 
*/ 




public class Dbhandler extends SQLiteOpenHelper { 


    private ContentResolver myCR; 

    private static int DATABASE_VERSION = 2; 
    private static String DATABASE_NAME = "distanceDB.db"; 
    public static String TABLE_DISTANCES = "distances"; 

    public static final String COLUMN_ID ="_id"; 
    public static final String COLUMN_DESCRIPTION = "COLUMN_DESCRIPTION"; 
    public static final String COLUMN_DISTANCE = "COLUMN_DISTANCE"; 


    public Dbhandler(Context context 
      //, String name, 
         //SQLiteDatabase.CursorFactory factory, int version 
         ) { 
     super(context, DATABASE_NAME, 
       //factory 
       null, DATABASE_VERSION); 
     myCR = context.getContentResolver(); // obtaining reference to content resolver in content provider 
    } 


    @Override 
    public void onCreate(SQLiteDatabase db) { 
     String CREATE_DISTANCES_TABLE = "CREATE TABLE " + 
       TABLE_DISTANCES + "(" 
       + 
       COLUMN_ID + 
       " _id INTEGER PRIMARY KEY," + COLUMN_DESCRIPTION 
       + " TEXT," + COLUMN_DISTANCE + " REAL" + ")"; 
     db.execSQL(CREATE_DISTANCES_TABLE); 


    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, 
          int newVersion) { 
     db.execSQL("DROP TABLE IF EXISTS " + TABLE_DISTANCES); 
     onCreate(db); 

    } 


    public void addDistances(int c,String a,String b) { 

     ContentValues values = new ContentValues(); 
     values.put(COLUMN_ID,c); 
     values.put(COLUMN_DESCRIPTION, a); 
     values.put(COLUMN_DISTANCE, b); 

     myCR.insert(MyContentProvider.CONTENT_URI, values); 
    } 

    public saveDistance findDistances(String Distancesname) { 
     String[] projection = { 
       COLUMN_ID, 
       COLUMN_DESCRIPTION, COLUMN_DISTANCE }; 

     String selection = "Distancesname = \"" + Distancesname + "\""; 

     Cursor cursor = myCR.query(MyContentProvider.CONTENT_URI, 
       projection, selection, null, 
       null); 

     saveDistance Distances = new saveDistance(); 

     if (cursor.moveToFirst()) { 
      cursor.moveToFirst(); 
      Distances.setID(Integer.parseInt(cursor.getString(0))); 
      Distances.setdesc(cursor.getString(1)); 
      Distances.setdistance(cursor.getString(2)); 
      cursor.close(); 
     } else { 
      Distances = null; 
     } 
     return Distances; 
    } 

    public boolean deleteDistances(String Distancesname) { 

     boolean result = false; 

     String selection = "Distancesname = \"" + Distancesname + "\""; 

     int rowsDeleted = myCR.delete(MyContentProvider.CONTENT_URI, 
       selection, null); 

     if (rowsDeleted > 0) 
      result = true; 

     return result; 
    } 



} 

这是saveDistance类

package com.spydotechcorps.hwfar.database; 

/** 
* Created by INGENIO on 3/8/2015. 
*/ 
public class saveDistance { 
    public int _id; 
    public String _desc; 
    public String _distance; 

    public void Distances() { 

    } 

    /*public void Distances(int id, String desc, String distance) { 
     this._id = id; 
     this._desc = desc; 
     this._distance = distance; 
    }*/ 
    public void Distances(
      //int k, 
     String desc, String distance) { 
     //this._id=1; 
     this._desc = desc; 
     this._distance = distance; 
    } 

    public void setID(int id) { 
     this._id = id; 
    } 

    public int getID() { 
     return this._id; 
    } 

    public void setdesc(String desc) { 
     this._desc = desc; 
    } 

    public String getdesc() { 
     return this._desc; 
    } 

    public void setdistance(String distance) { 
     this._distance = distance; 
    } 

    public String getdistance() { 
     return this._distance; 
    } 
} 

Answer 1

你可以试着改变你的addDistances dbHelper类的方法为您已将_id列用作整数和主键。尝试使用SQLite Inject查询而不是内容值而不传递_id列值。我认为由于主键值，数据不会插入/冲突。

您可以将_id列类型更改为“integer primary key autoincrement”，并且不会在插入查询中传递_id列值。 Sqlite DB将自动处理_id列值。无需从用户端提供。

我希望这会帮助你。

Answer 2

你做了一个错误在创建表的查询......检查一次，然后给予反馈...

@Override 
    public void onCreate(SQLiteDatabase db) { 
     String CREATE_DISTANCES_TABLE = "CREATE TABLE " + 
       TABLE_DISTANCES + "(" 
       + 
       COLUMN_ID + " INTEGER PRIMARY KEY," + COLUMN_DESCRIPTION + " TEXT," + COLUMN_DISTANCE + " INTEGER" + ")"; 
     db.execSQL(CREATE_DISTANCES_TABLE); 


    }