目前我的 SQLite 数据库运行良好,我已经阅读了各种方法,例如实现此目的的方法,尽管目前我在设置 Date 构造函数以及如何定义数据以将其放入数据库时遇到问题(并取回它!)
到目前为止,我已经使用 static final String 来定义我的数据变量,不确定哪种是使用 Date 的正确方法。
我不关心时间,只关心条目的创建日期。
下面是我的java类:
import java.sql.Date;
import java.text.SimpleDateFormat;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class Stats {
public static final String KEY_ROWID = "_id";
public static final String KEY_WEIGHT = "weight";
public static final String KEY_WAIST = "waist";
public static final String KEY_CHEST = "chest";
public static final String KEY_LEGS = "legs";
public static final String KEY_ARMS = "arms";
public static final String KEY_DATE = "date";
private static final String DATABASE_NAME = "statsDB";
private static final String DATABASE_TABLE = "personalStats";
private static final int DATABASE_VERSION = 3;
private DbHelper ffHelper;
private final Context ffContext;
private SQLiteDatabase ffDatabase;
private static class DbHelper extends SQLiteOpenHelper {
public DbHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" + KEY_ROWID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_WEIGHT
+ " TEXT NOT NULL, " + KEY_WAIST + " TEXT NOT NULL, "
+ KEY_CHEST + " TEXT NOT NULL, " + KEY_LEGS
+ " TEXT NOT NULL, " + KEY_ARMS + " TEXT NOT NULL, "
+ KEY_DATE + " TEXT NOT NULL);");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
public Stats(Context c) {
ffContext = c;
}
public Stats open() throws SQLException {
ffHelper = new DbHelper(ffContext);
ffDatabase = ffHelper.getWritableDatabase();
return this;
}
public void close() {
ffHelper.close();
}
public long createEntry(String weight, String waist, String chest, String legs, String arms) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = new Date();
ContentValues cv = new ContentValues();
cv.put(KEY_WEIGHT, weight);
cv.put(KEY_WAIST, waist);
cv.put(KEY_CHEST, chest);
cv.put(KEY_LEGS, legs);
cv.put(KEY_ARMS, arms);
cv.put("date_created", dateFormat.format(date));
return ffDatabase.insert(DATABASE_TABLE, null, cv);
}
public String getData() {
String[] columns = new String[] { KEY_ROWID, KEY_WEIGHT, KEY_WAIST, KEY_CHEST, KEY_LEGS, KEY_ARMS, KEY_DATE };
Cursor c = ffDatabase.query(DATABASE_TABLE, columns, null, null, null,
null, null);
String result = "";
int iRow = c.getColumnIndex(KEY_ROWID);
int iWeight = c.getColumnIndex(KEY_WEIGHT);
int iWaist = c.getColumnIndex(KEY_WAIST);
int iChest = c.getColumnIndex(KEY_CHEST);
int iLegs = c.getColumnIndex(KEY_LEGS);
int iArms = c.getColumnIndex(KEY_ARMS);
int iDate = c.getColumnIndex(KEY_DATE);
for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) {
result = result + c.getString(iRow) + " " + c.getString(iWeight)
+ " " + c.getString(iWaist)
+ " " + c.getString(iChest)
+ " " + c.getString(iLegs)
+ " " + c.getString(iArms)
+ " " + c.getString(iDate)+ "\n";
}
return result;
}
}
显然,任何时候提到 Date 都是我试图添加这个额外功能的地方。