我在将数据插入SQLite数据库时遇到困难。当我调用addData()方法时，我的应用程序崩溃了。我在addData方法中的MainActivity类中调用GameView方法（位于onTouchEvent）。我需要将turns整数插入到数据库的COLUMN_SCORES列中。感谢任何帮助！
DatabaseHelper.java：
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "scores.db";
public static final String TABLE_NAME = "scores_table";
public static final String COLUMN_ID = "ID";
public static final String COLUMN_SCORE = "SCORE";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table " + TABLE_NAME +" (ID INTEGER PRIMARY KEY AUTOINCREMENT, SCORE INTEGER)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
public boolean insertData(String score) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COLUMN_SCORE, score);
long result = db.insert(TABLE_NAME, null, contentValues);
if(result == -1) {
return false;
}
else {
return true;
}
}
public Cursor getAllData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from " + TABLE_NAME, null);
return res;
}
public boolean updateData(String id, String score) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COLUMN_ID, id);
contentValues.put(COLUMN_SCORE, score);
db.update(TABLE_NAME, contentValues, "ID = ?", new String[] { id });
return true;
}
public Integer deleteData(String id) {
SQLiteDatabase db = this.getWritableDatabase();
return db.delete(TABLE_NAME, "ID = ?", new String[] { id });
}
}
GameView.java：
public class GameView extends View {
int mcolumns = 5;
int mrows = 5;
private NetwalkGrid mGame = new NetwalkGrid(mcolumns, mrows);
private GestureDetector mGestureDetector;
Random rand = new Random();
int sizeSqX;
int sizeSqY;
int sizeSq;
public static int turns;
Paint bgPaint;
public GameView(Context context) {
super(context);
init();
}
private void init() {
bgPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
bgPaint.setStyle(Paint.Style.FILL);
bgPaint.setColor(0xff0000ff);
mGame.gridCopy();
for (int col = 0; col < mGame.getColumns(); col++) {
for (int row = 0; row < mGame.getRows(); row++) {
int num = rand.nextInt(3) + 1;
for (int turns = 1; turns < num; turns++) {
mGame.rotateRight(col, row);
}
}
}
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.BLACK);
sizeSqX = getWidth() / mcolumns;
sizeSqY = getHeight() / mrows;
if (sizeSqX < sizeSqY) {
sizeSq = sizeSqX;
}
else {
sizeSq = sizeSqY;
}
Bitmap b = BitmapFactory.decodeResource(getResources(), R.drawable.placeholder);
//Bitmap s = BitmapFactory.decodeResource(getResources(), R.drawable.straight);
//Bitmap dl = BitmapFactory.decodeResource(getResources(), R.drawable.downleft);
int cellContent;
//square = get width / col
int square = 140;
for (int col = 0; col < mGame.getColumns(); col++) {
for (int row = 0; row < mGame.getRows(); row++) {
cellContent = mGame.getGridElem(col,row);
if (cellContent == 1) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.up_down); // Image for down position
if (cellContent == 65 && mGame.checkWin()) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.up_down_connected);
}
}
else if (cellContent == 2) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.left_right); // Right position
if (mGame.checkWin()) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.left_right_connected);
}
}
else if (cellContent == 3) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.right_down); // Down right position WORKS
if (mGame.checkWin()) {
b = BitmapFactory.decodeResource(getResources(), R.drawable.right_down_connected);
}
else {
b = BitmapFactory.decodeResource(getResources(), R.drawable.placeholder2); //
}
canvas.drawBitmap(b, null,new Rect(col * sizeSq, row * sizeSq,col*sizeSq+sizeSq, row*sizeSq+sizeSq), null);
//Paint paint = new Paint();
//paint.setColor(Color.WHITE);
// paint.setStyle(Paint.Style.FILL);
TextPaint tp = new TextPaint();
tp.setColor(Color.GREEN);
tp.setTextSize(70);
tp.setTypeface(Typeface.create("Courier", Typeface.BOLD));
canvas.drawText("Moves: " + String.valueOf(turns), 10, 1180, tp);
canvas.drawText("High score: ", 10, 1280, tp);
}
}
}
//SoundPoolPlayer sound = new SoundPoolPlayer(getContext());
@Override
public boolean onTouchEvent(MotionEvent event) {
//boolean eventConsumed = mGestureDetector.onTouchEvent(event);
//GameView mGameView = new GameView(getApplicationContext());
//if (eventConsumed) {
int x = (int) event.getX();
int y = (int) event.getY();
int column = getColTouched(event.getX());
int row = getRowTouched(event.getY());
try {
mGame.rotateRight(column, row);
System.out.println(mcolumns);
turns++;
MainActivity main = new MainActivity();
//main.setTurns();
main.addData();
//main.getData();
mGame.checkWin();
if (mGame.checkWin()) {
System.out.println("check win works");
invalidate();
//main.setTurns();
//main.AddData();
}
invalidate();
}
catch (ArrayIndexOutOfBoundsException err) {
System.out.println("User has pressed outside game grid - exception caught");
}
//sound.playShortResource(R.raw.click);
// sound.release();
return super.onTouchEvent(event);
}
public int getColTouched(float x) {
return (int) (x / sizeSq);
}
public int getRowTouched(float y) {
return (int) (y / sizeSq);
}
public int getCols() {
return mcolumns;
}
public void setColRow(int columns, int rows) {
this.mcolumns = columns;
this.mrows = rows;
}
public int getTurns() {
return turns;
}
}
MainActivity.java：
公共类MainActivity扩展了AppCompatActivity {
private GestureDetector mGestureDetector;
private ImageView imageView;
private RadioGroup radioGroup;
private int mcolumns;
private int mrows;
DatabaseHelper myDb;
String test = "test data";
int turns;
static Context appcon;
String highScore;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
appcon = this;
myDb = new DatabaseHelper(this);
}
public void runGame(View view){
Intent intent = new Intent(this, GameViewActivity.class);
startActivity(intent);
}
public void runInstructions(View view) {
Intent intent = new Intent(this, InstructionsActivity.class);
startActivity(intent);
}
public void setTurns() {
//GameView mGameView = new GameView(getApplicationContext());
this.turns = GameView.turns;
System.out.println("Turns: " + Integer.toString(turns));
}
public void addData() {
boolean isInserted = myDb.insertData(test);
if(isInserted == true) {
System.out.println("Data inserted");
}
else {
System.out.println("Data NOT inserted");
}
}
public void getData() {
Cursor res = myDb.getAllData();
StringBuffer buffer = new StringBuffer();
while(res.moveToNext()) {
buffer.append(res.getString(1));
}
System.out.println(buffer.toString());
}
}
答案 0 :(得分：0)
在onTouchEvent类的GameView中，而不是创建一个新的MainActivity实例，我怀疑它是否正在运行failiure，您可以调用{{1}的insertData方法直接类。例如而不是使用： -
DatabaseHelper尝试
MainActivity main = new MainActivity();
//main.setTurns();
main.addData();
//main.getData();