怎么在Android中实现一个可标记日历功能

package com.xugongming38.editcalendar.utils;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;public class DatabaseHelper extends SQLiteOpenHelper { public static final String CREATE_DIARY = "create table Hair("   + "id integer primary key autoincrement, "   + "content text)"; private Context mContext; public DatabaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){  super(context, name, factory, version);  mContext = context; } @Override public void onCreate(SQLiteDatabase db) {  db.execSQL(CREATE_DIARY); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {  db.execSQL("drop table if exists Hair");  onCreate(db); }}