我不完全确定会发生什么，我知道当我尝试插入时存在不匹配，但是当我仔细检查我的代码时，我无法理解为什么它会吐出那个错误。我只是想插入一个用户名和密码（两个都是字符串）。
背景：
在我的 RegisterLoginActivity.java 中，当用户点击TextView“创建帐户”时，它会抓取用户名和密码并将其转换为字符串。
然后在我的 DatabaseOperations.java 中，我使用函数putInformation（）来插入数据。
我的 TableData.java 只包含我的表信息。
RegisterLoginActivity.java;
package com.example.envy.energyvue;
import android.content.Context;
import android.database.Cursor;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class RegisterLoginActivity extends AppCompatActivity {
EditText USER_NAME, USER_PASS;
TextView REG;
String user_name, user_pass;
Context ctx = this;
Button login;
@Override
protected void onCreate(Bundle savedInstanceState) {
//getActionBar().hide();
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register_login);
USER_NAME = (EditText) findViewById(R.id.userText);
USER_PASS = (EditText) findViewById(R.id.passText);
REG = (TextView) findViewById(R.id.createAccount);
REG.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
user_name = USER_NAME.getText().toString();
user_pass = USER_PASS.getText().toString();
DatabaseOperations DB = new DatabaseOperations(ctx);
DB.putInformation(DB,user_name, user_pass);
}
});
// IGNORE THIS PORTION, IT IS FOR LOGGING IN AFTER I REGISTER
//********************************************
login = (Button) findViewById(R.id.login);
login.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view) {
user_name = USER_NAME.getText().toString();
user_pass = USER_NAME.getText().toString();
DatabaseOperations DB = new DatabaseOperations(ctx);
Cursor CR = DB.getInformation(DB);
CR.moveToFirst();
boolean loginstatus = false;
String NAME = "";
do{
if(user_name.equals(CR.getString(0)) && user_pass.equals(CR.getString(1))){
loginstatus = true;
}
}while(CR.moveToFirst());
if(loginstatus){
Toast.makeText(getBaseContext(), "Login Success", Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(getBaseContext(), "Login Failed", Toast.LENGTH_LONG).show();
}
}
});
}
}
DatabaseOperations.java;
package com.example.envy.energyvue;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
/**
* Created by Envy on 7/13/2016.
*
* private static final String SQL_CREATE_ENTRIES =
"CREATE TABLE " + TableData.TableInfo.TABLE_NAME + " (" + TableData.TableInfo._ID +
" INTEGER PRIMARY KEY," + TableData.TableInfo.COLUMN_NAME_USER_ID + TEXT_TYPE + COMMA_SEP + TableData.TableInfo.COLUMN_NAME_PASSWORD + TEXT_TYPE + " );";
*/
public class DatabaseOperations extends SQLiteOpenHelper{
public static final int DATABASE_VERSION = 1;
public static final String DATABASE_NAME = "UserData.db";
private static final String TEXT_TYPE = " TEXT";
private static final String COMMA_SEP = ",";
private static final String SQL_CREATE_ENTRIES =
"CREATE TABLE " + TableData.TableInfo.TABLE_NAME + " (" + TableData.TableInfo._ID +
" INTEGER PRIMARY KEY," + TableData.TableInfo.COLUMN_NAME_USER_ID + TEXT_TYPE + COMMA_SEP + TableData.TableInfo.COLUMN_NAME_PASSWORD + TEXT_TYPE + " );";
private static final String SQL_DELETE_ENTRIES =
"DROP TABLE IF EXISTS " + TableData.TableInfo.TABLE_NAME;
public DatabaseOperations(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public void onCreate(SQLiteDatabase db) {
db.execSQL(SQL_CREATE_ENTRIES);
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// This database is only a cache for online data, so its upgrade policy is
// to simply to discard the data and start over
db.execSQL(SQL_DELETE_ENTRIES);
onCreate(db);
}
public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
onUpgrade(db, oldVersion, newVersion);
}
public void putInformation(DatabaseOperations dop, String user_id, String password){
SQLiteDatabase SQ = dop.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(TableData.TableInfo.COLUMN_NAME_USER_ID, user_id);
cv.put(TableData.TableInfo.COLUMN_NAME_PASSWORD, password);
System.out.print("LOLOLSDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD");
long newRowId;
newRowId = SQ.insert(
TableData.TableInfo.TABLE_NAME,
null,
cv);
}
public Cursor getInformation(DatabaseOperations dop){
SQLiteDatabase SQ = dop.getReadableDatabase();
String[] projection = {
TableData.TableInfo._ID,
TableData.TableInfo.COLUMN_NAME_USER_ID,
TableData.TableInfo.COLUMN_NAME_PASSWORD
};
Cursor CR = SQ.query(TableData.TableInfo.TABLE_NAME, projection, null, null, null, null, null);
return CR;
}
}
TableData.java;
package com.example.envy.energyvue;
import android.provider.BaseColumns;
/**
* Created by Envy on 7/13/2016.
*/
public class TableData {
public TableData(){}
public static abstract class TableInfo implements BaseColumns {
public static final String TABLE_NAME = "login_information";
public static final String COLUMN_NAME_USER_ID = "user_id";
public static final String COLUMN_NAME_PASSWORD = "password";
}
}
错误：
07-15 21:18:47.996 24361-24361/com.example.envy.energyvue E/SQLiteLog: (20) statement aborts at 5: [INSERT INTO login_information(password,user_id) VALUES (?,?)] datatype mismatch
07-15 21:18:47.996 24361-24361/com.example.envy.energyvue E/SQLiteDatabase: Error inserting password= bbb user_id=bbb
android.database.sqlite.SQLiteDatatypeMismatchException: datatype mismatch (code 20)
#################################################################
Error Code : 20 (SQLITE_MISMATCH)
Caused By : Data type mismatch.
(datatype mismatch (code 20))
#################################################################
at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:915)
at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1609)
at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1479)
at com.example.envy.energyvue.DatabaseOperations.putInformation(DatabaseOperations.java:59)
at com.example.envy.energyvue.RegisterLoginActivity$1.onClick(RegisterLoginActivity.java:37)
at android.view.View.performClick(View.java:5697)
at android.widget.TextView.performClick(TextView.java:10814)
at android.view.View$PerformClick.run(View.java:22526)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:158)
at android.app.ActivityThread.main(ActivityThread.java:7229)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
答案 0 :(得分：0)
好吧......好几个小时之后，我想出来了......我把我的数据库名称加上了“.db”扩展名，这让事情搞得一团糟。