Android SQLite：INSERT detailMessage null

我嘗試從db_insert.java插入數據，並按MyDB.java中的方法處理數據。Android SQLite：INSERT detailMessage null

public void append(String n,int p) { 
     String str = "INSERT INTO " + TABLE_NAME + " (" + NAME + "," + PRICE + ") VALUES (" + n +"," + p + ")"; 
     db.execSQL(str);  
}

在調試模式下，n & p從db_insert.java獲取數據。

到目前爲止，沒關係。但是當進程db.execSQL(str);時，該應用程序將崩潰。

有人知道爲什麼嗎？

logcat的

02-07 00:16:48.467: I/Process(979): Sending signal. PID: 979 SIG: 9 02-07 00:17:17.827: 

E/MyDBlog(1109): click insert_OKs 02-07 00:17:17.827: D/AndroidRuntime(1109): Shutting 


down VM 02-07 00:17:17.827: W/dalvikvm(1109): threadid=1: thread exiting with uncaught 

exception (group=0x2aac8578) 02-07 00:17:17.827: E/AndroidRuntime(1109): FATAL EXCEPTION: 

main 02-07 00:17:17.827: E/AndroidRuntime(1109): java.lang.NullPointerException 02-07 

00:17:17.827: E/AndroidRuntime(1109): at com.example.mydb.MyDB.append(MyDB.java:39) 02-07 

00:17:17.827: E/AndroidRuntime(1109): at com.example.mydb.db_insert$1.onClick(db_insert.java:66) 02-07 00:17:17.827: 

E/AndroidRuntime(1109): at android.view.View.performClick(View.java:2552) 02-07 

00:17:17.827: E/AndroidRuntime(1109): at android.view.View$PerformClick.run(View.java:9229) 

02-07 00:17:17.827: E/AndroidRuntime(1109): at android.os.Handler.handleCallback(Handler.java:587) 02-07 00:17:17.827: 

E/AndroidRuntime(1109): at android.os.Handler.dispatchMessage(Handler.java:92) 02-07 

00:17:17.827: E/AndroidRuntime(1109): at android.os.Looper.loop(Looper.java:130) 02-07 

00:17:17.827: E/AndroidRuntime(1109): at android.app.ActivityThread.main(ActivityThread.java:3701) 02-07 00:17:17.827: E/AndroidRuntime(1109): at java.lang.reflect.Method.invokeNative(Native Method) 02-07 00:17:17.827: E/AndroidRuntime(1109): at java.lang.reflect.Method.invoke(Method.java:507) 02-07 00:17:17.827: E/AndroidRuntime(1109): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866) 02-07 

00:17:17.827: E/AndroidRuntime(1109): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624) 02-07 00:17:17.827: 

E/AndroidRuntime(1109): at dalvik.system.NativeStart.main(Native Method)

我的應用程序首先使用open（）來打開數據庫。

MyDB.java

public SQLiteDatabase db=null; 
private Context mCtx = null; 
public MyDB(Context ctx){ 
    this.mCtx = ctx;  
} 
public void open() throws SQLException { // 開啟已經存在的資料庫 
    db = mCtx.openOrCreateDatabase(DATABASE_NAME, 0, null); 
     try {  
      db.execSQL(CREATE_TABLE);// 建立資料表 
     }catch (Exception e) {  
     } 
    }

來源

2013-02-06 Maksim

private static final String INSERT = "insert into contact(name,number) values(?,?)"; 
public DataHelper(Context context) 
    { 
     this.context=context; 
     openhelper=new OpenHelper(context); 
     this.db=openhelper.getWritableDatabase(); 
     this.insertStmt1 = this.db.compileStatement(INSERT); 

    } 

public boolean insert(String name, String number) 
    { 
    openhelper=new OpenHelper(context); 
    db=openhelper.getWritableDatabase(); 

    String person=name; 


    String values1=number; 

    this.insertStmt1.bindString(1, person); 
    this.insertStmt1.bindString(2, number); 

    this.insertStmt1.executeInsert(); 

    Toast.makeText(context, "Value inserted", 10000).show(); 
    openhelper.Close_DB(db); 
    return true; 
    }

這是爲了插入值的示例根據您的需要修改此數據庫。 :)

來源

2013-02-11 05:08:06

使用db.insert方法和存儲的值到ContentaValues objest ..

參閱this blog爲SQLiteDatabase實例

來源

2013-02-06 16:40:16 user2047685

我用CV來插入數據.. 發生同樣的錯誤.. – Maksim

Android SQLite：INSERT detailMessage null

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