android - 如何将所选项目保存在日历中

Question

我想将所选项目保存在日历中。重新启动后，它们将被重置。我如何实现他们的发明？选择 可能的示例，我应该使用另一个库或数据库吗？

这是我尝试编写数据库：

MainActivity.kt：

class HomeActivity : AppCompatActivity() {
var dbHelper: DBHelper? = null
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.exmaple_1_fragment)
    val daysOfWeek = daysOfWeekFromLocale()
    legendLayout.children.forEachIndexed { index, view ->
        (view as TextView).apply {
            text =
                daysOfWeek[index].getDisplayName(TextStyle.SHORT, Locale.ENGLISH).toUpperCase(
                    Locale.ENGLISH
                )
            setTextColorRes(R.color.example_1_white_light)
        }
    }
    dbHelper = DBHelper(this, name = "main", version = 1)
    val currentMonth = YearMonth.now()
    val startMonth = currentMonth.minusMonths(10)
    val endMonth = currentMonth.plusMonths(10)
    exOneCalendar.setup(startMonth, endMonth, daysOfWeek.first())
    exOneCalendar.scrollToMonth(currentMonth)

    class DayViewContainer(view: View) : ViewContainer(view) {
        // Will be set when this container is bound. See the dayBinder.
        lateinit var day: CalendarDay
        val textView = view.exOneDayText
        val database = dbHelper!!.writableDatabase
        val contentValues = ContentValues()
        init {
            view.setOnClickListener {
                if (day.owner == DayOwner.THIS_MONTH) {
                    if (selectedDates.contains(day.date)) {
                        selectedDates.remove(day.date)
                        contentValues.put(DBHelper.DATABASE_DAY, selectedDates.contains(day.date))
                        database.insert(DBHelper.TABLE_DATA, null, contentValues)
                    } else {
                        selectedDates.add(day.date)
                        database.delete(DBHelper.TABLE_DATA, null, null)
                    }
                    exOneCalendar.notifyDayChanged(day)
                }
            }
        }
    }

DBHelper.kt：

class DBHelper(context: Context?, name: String?, version: Int) :
SQLiteOpenHelper(context, name, null, version) {
override fun onCreate(db: SQLiteDatabase) {
    db.execSQL(
        "create table " + TABLE_DATA +
                "(" + DATABASE_DAY + " text" + ")"
    )
}

override fun onUpgrade(
    db: SQLiteDatabase,
    oldVersion: Int,
    newVersion: Int
) {
}

companion object {
    const val DATABASE_VERSION = 1
    const val TABLE_DATA = "list"
    const val DATABASE_DAY = "day"
}

项目链接

标签： androidkotlincalendar

Answer 1

数据库助手

class DBHelper(context: Context) : SQLiteOpenHelper(context, DATABASE_NAME, null, DATABASE_VERSION){
companion object {
    const val DATABASE_VERSION = 1
    const val DATABASE_NAME = "DateManager.db"
    const val TABLE_DATE = "date"
    const val COLUMN_USER_ID = "user_id"
    const val COLUMN_DATES = "dates"
}
private val DROP_USER_TABLE = "DROP TABLE IF EXISTS $TABLE_DATE"
private val CREATE_DATA_TABLE = ("CREATE TABLE " + TABLE_DATE + "( "
        + COLUMN_USER_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COLUMN_DATES + " TEXT" + ")")
override fun onCreate(db: SQLiteDatabase) {
    db!!.execSQL(CREATE_DATA_TABLE)
}

override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
    db.execSQL(DROP_USER_TABLE)
    onCreate(db)
}

fun getAllDates(): String {
    var allUser: String = ""
    val db = readableDatabase
    val selectALLQuery = "SELECT * FROM $TABLE_DATE"
    val cursor = db.rawQuery(selectALLQuery, null)
    if (cursor != null) {
        if (cursor.moveToFirst()) {
            do {
                var date_read = cursor.getString(cursor.getColumnIndex(COLUMN_DATES))
                allUser = "$allUser\n$date_read"
            } while (cursor.moveToNext())
        }
    }
    cursor.close()
    db.close()
    return allUser
}
fun deleteUser(model: DBmodel) {
    val db = this.writableDatabase
    db.delete(TABLE_DATE, "$COLUMN_DATES = '${model.date}'", null)
    db.close()
}
fun addUser(model: DBmodel):Long{
    val database = this.writableDatabase
    val values = ContentValues()
    values.put(COLUMN_DATES, model.date)
    val success = database.insert(TABLE_DATE, null , values)
    database.close()
    return success
}

}

MainActivity.kt

class HomeActivity : AppCompatActivity() {
private val activity = this@HomeActivity
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.exmaple_1_fragment)
    val daysOfWeek = daysOfWeekFromLocale()
    database = DBHelper(this)
    legendLayout.children.forEachIndexed { index, view ->
        (view as TextView).apply {
            text =
                daysOfWeek[index].getDisplayName(TextStyle.SHORT, Locale.ENGLISH).toUpperCase(
                    Locale.ENGLISH
                )
            setTextColorRes(R.color.example_1_white_light)
        }
    }
    val currentMonth = YearMonth.now()
    val startMonth = currentMonth.minusMonths(10)
    val endMonth = currentMonth.plusMonths(10)
    exOneCalendar.setup(startMonth, endMonth, daysOfWeek.first())
    exOneCalendar.scrollToMonth(currentMonth)
    class DayViewContainer(view: View) : ViewContainer(view) {

        lateinit var day: CalendarDay
        val textView = view.exOneDayText
        init {
            view.setOnClickListener {
                if (day.owner == DayOwner.THIS_MONTH) {
                    if (selectedDates.contains(day.date)) {
                        selectedDates.remove(day.date)
                        Toast.makeText(this@HomeActivity, "("+day.date.toString().trim()+") deleted", Toast.LENGTH_SHORT).show()
                        val user = DBmodel(date = day.date.toString().trim())
                        database!!.deleteUser(user)
                    } else {
                        selectedDates.add(day.date)
                        val user = DBmodel(date = day.date.toString().trim())
                        database!!.addUser(user)
                        Toast.makeText(this@HomeActivity, "("+day.date.toString().trim()+") added", Toast.LENGTH_SHORT).show()
                    }
                    exOneCalendar.notifyDayChanged(day)
                }
            }
        }
    }

    exOneCalendar.dayBinder = object : DayBinder<DayViewContainer> {
        override fun create(view: View) = DayViewContainer(view)
        override fun bind(container: DayViewContainer, day: CalendarDay)
        {
            container.day = day
            val textView = container.textView
            val db = database!!.readableDatabase
            var allUser: String = ""
            val selectALLQuery = "SELECT * FROM ${DBHelper.TABLE_DATE}"
            val cursor = db.rawQuery(selectALLQuery, null)
            textView.text = day.date.dayOfMonth.toString()

            if (cursor != null) {
                if (cursor.moveToFirst()) {
                    do {
                        var date_read =
                            cursor.getString(cursor.getColumnIndex(DBHelper.COLUMN_DATES))
                        when {
                            day.date.toString() == date_read -> {
                                selectedDates.add(day.date)
                            }
                        }
                    } while (cursor.moveToNext())
                }
            }
            cursor.close()
            db.close()

            if (day.owner == DayOwner.THIS_MONTH) {
                when {
                    selectedDates.contains(day.date) -> {
                        textView.setTextColorRes(R.color.example_1_bg)
                        textView.setBackgroundResource(R.drawable.example_1_selected_bg)
                    }
                    today == day.date -> {
                        textView.setTextColorRes(R.color.example_1_white)
                        textView.setBackgroundResource(R.drawable.example_1_today_bg)
                    }
                    else -> {
                        textView.setTextColorRes(R.color.example_1_white)
                        textView.background = null
                    }
                }
            } else {
                textView.setTextColorRes(R.color.example_1_white_light)
                textView.background = null
            }
        }
    }

数据库模型

data class DBmodel(val id: Int = -1, val date: String)