Question

我想问一下将Android数据存储到SQLite数据库（我是SQLite数据库的新手）。我一直在尝试将数据存储到SQLite数据库，但是当我用SQLiteStudio看到数据库时，数据是空的。这是我的代码：

DatabaseHelper.java

package com.example.toolsmanager;

    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;

    public class DatabaseHelper extends SQLiteOpenHelper {

    private static final String DATABASE_NAME = "btm.db";
    private static final int DATABASE_VERSION = 1;

    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    public static final String TABLE_1 = "oneroundsingle";

    public static final String TABLE1_COLUMN1 = "_ID";
    public static final String TABLE1_COLUMN2 = "GAMETYPE";
    public static final String TABLE1_COLUMN3 = "PLAYER1";
    public static final String TABLE1_COLUMN4 = "PLAYER2";
    public static final String TABLE1_COLUMN5 = "SCORE";
    public static final String TABLE1_COLUMN6 = "WINNER";


    public static final String CREATE_TABLE_ORS = "create table" + TABLE_1 + " ( " +
            TABLE1_COLUMN1 + " integer primary key autoincrement, " +
            TABLE1_COLUMN2 + " text, " +
            TABLE1_COLUMN3 + " text, " +
            TABLE1_COLUMN4 + " text, " +
            TABLE1_COLUMN5 + " text, " +
            TABLE1_COLUMN6 + " text " + ");";

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_TABLE_ORS);
        db.execSQL(CREATE_TABLE_ORD);
        db.execSQL(CREATE_TABLE_RS);
        db.execSQL(CREATE_TABLE_RD);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("drop table if exists" + TABLE_1);
        db.execSQL("drop table if exists" + TABLE_2);
        db.execSQL("drop table if exists" + TABLE_3);
        db.execSQL("drop table if exists" + TABLE_4);
        onCreate(db);
    }
    }

OR_SingleCount.java

package com.example.toolsmanager;

    import android.content.ContentValues;
    import android.content.DialogInterface;
    import android.content.Intent;
    import android.database.sqlite.SQLiteDatabase;
    import android.support.v7.app.AlertDialog;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.TextView;
    import android.widget.Toast;

    public class OR_SingleCount extends AppCompatActivity {

    int player1_score, player2_score, final_score;
    TextView text_player1_name, text_player2_name;
    String score, winner;
    DatabaseHelper databaseHelper;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_or_single_count);

        text_player1_name = (TextView)findViewById(R.id.player1_name);
        text_player1_name.setText(getIntent().getExtras().getString("player1"));

        text_player2_name = (TextView)findViewById(R.id.player2_name);
        text_player2_name.setText(getIntent().getExtras().getString("player2"));

    }

    public void singleCount(View v) {
        int id = v.getId();
        if (id == R.id.player1_plus) {
            player1_score += 1;
            TextView text_player1_score = (TextView) findViewById(R.id.player1_score);
            text_player1_score.setText(String.valueOf(player1_score));
        } else if (id == R.id.player1_minus && player1_score != 0) {
            player1_score -= 1;
            TextView text_player1_score = (TextView) findViewById(R.id.player1_score);
            text_player1_score.setText(String.valueOf(player1_score));
        } else if (id == R.id.player2_plus) {
            player2_score += 1;
            TextView text_player2_score = (TextView) findViewById(R.id.player2_score);
            text_player2_score.setText(String.valueOf(player2_score));
        } else if (id == R.id.player2_minus && player2_score != 0) {
            player2_score -= 1;
            TextView text_player2_score = (TextView) findViewById(R.id.player2_score);
            text_player2_score.setText(String.valueOf(player2_score));
        }
        finalScore();
    }

    public void finalScore(){
        if ((player1_score == 21 && player2_score < 20) || (player2_score == 21 && player1_score < 20)) {
            final_score = 21;
            getWinner();
        } else if (player1_score == 30 || player2_score == 30) {
            final_score = 30;
            getWinner();
        } else if (player1_score >= 20 && player2_score >= 20) {
            if (player1_score == player2_score + 2) {
                final_score = player1_score;
                getWinner();
            } else if (player2_score == player1_score + 2) {
                final_score = player2_score;
                getWinner();
            }
        }
    }

    public void getWinner() {
        if (player1_score == final_score){
            winner = text_player1_name.getText().toString();
            String print_winner = winner + " is the winner";
            Toast.makeText(getApplicationContext(),print_winner, Toast.LENGTH_LONG).show();
        } else if(player2_score == final_score) {
            winner = text_player2_name.getText().toString();
            String print_winner = winner + " is the winner";
            Toast.makeText(getApplicationContext(), print_winner, Toast.LENGTH_LONG).show();
        }

        score = player1_score + " - " + player2_score;
        String gametype = "Single";
        addORSingleData(gametype,
                text_player1_name.getText().toString(),
                text_player2_name.getText().toString(),
                score,
                winner);

        AlertDialog repeatdialog= new AlertDialog.Builder(this)
                .setTitle("Game Finish")
                .setMessage("Do you want to repeat the game?")
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int whichButton) {
                        player1_score = 0;
                        player2_score = 0;
                        recreate();
                    }
                })
                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        Intent i = new Intent(OR_SingleCount.this, OneRoundMatch.class);
                        i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        startActivity(i);
                        finish();
                    }
                }).create();
        repeatdialog.show();
    }

    public void addORSingleData(String gametype, String player1, String player2, String score, String winner){
        databaseHelper = new DatabaseHelper(this);
        SQLiteDatabase db = databaseHelper.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(DatabaseHelper.TABLE1_COLUMN2, gametype);
        contentValues.put(DatabaseHelper.TABLE1_COLUMN3, player1);
        contentValues.put(DatabaseHelper.TABLE1_COLUMN4, player2);
        contentValues.put(DatabaseHelper.TABLE1_COLUMN5, score);
        contentValues.put(DatabaseHelper.TABLE1_COLUMN6, winner);
        db.insert(DatabaseHelper.TABLE_1, null, contentValues);
    }
    }

我的代码出了什么问题？

Answer 1

我从未使用过SQLite Studio，因此如果我愿意，我可以解决问题，但你可以设置光标：

Cursor cursor = db.query(TABLE_NAME,null,null,null,null,null,null);

然后致电

Toast.makeText(this, "" + cursor.getCount(), Toast.LENGTH_SHORT).show();

查看您是否正在插入任何数据。另外，onCreate方法中的额外表格是什么？

Android数据未存储到SQLite数据库

1 个答案: