วิธีใช้ ParseQuery: ตัวอย่างและการทำงานบน Android

คู่มือการใช้ parse query ใน android บทนำ เราได้เห็นแล้วว่า parsequery parsequery กับ get get สามารถดึงข้อมูล parsequery parsequery จาก back4app ได้ มีวิธีอื่นๆ อีกมากมายในการดึงข้อมูลด้วย parsequery parsequery คุณสามารถดึงวัตถุหลายๆ ตัวพร้อมกัน ใช้เงื่อนไขกับวัตถุที่คุณต้องการดึง และอื่นๆ ในคู่มือนี้ คุณจะได้เจาะลึกเข้าไปใน parsequery parsequery คลาสและดูวิธีการทั้งหมดที่คุณสามารถใช้ในการสร้าง queries ของคุณ คุณจะใช้คลาสฐานข้อมูลง่ายๆ พร้อมข้อมูลที่จำลองขึ้นเพื่อทำการ queries โดยใช้ javascript console บน back4app คุณสามารถใช้ javascript console บน back4app เพื่อสร้างข้อมูลที่จำลองขึ้นได้อย่างง่ายดาย หรือคุณสามารถสร้างข้อมูลของคุณเองด้วยแอป android ของคุณโดยทำตาม คู่มือนี้ บทเรียนนี้ใช้แอปที่สร้างขึ้นใน android studio 4 1 1 โดยมี buildtoolsversion=30 0 2 buildtoolsversion=30 0 2 , compile sdk version = 30 0 2 compile sdk version = 30 0 2 และ targetsdkversion=30 targetsdkversion=30 ในทุกเวลา คุณสามารถเข้าถึงโปรเจกต์ android ที่สร้างขึ้นด้วยบทเรียนนี้ได้ที่ที่เก็บ github ของเรา ที่เก็บตัวอย่าง kotlin ที่เก็บตัวอย่าง java ข้อกำหนดเบื้องต้น ในการทำให้บทเรียนนี้เสร็จสมบูรณ์ เราต้องการ android studio แอปที่สร้างขึ้นบน back4app หมายเหตุ ติดตาม บทเรียนการสร้างแอป parse ใหม่ เพื่อเรียนรู้วิธีการสร้างแอป parse บน back4app แอป android ที่เชื่อมต่อกับ back4app หมายเหตุ ติดตาม บทเรียนการติดตั้ง parse sdk เพื่อสร้างโปรเจกต์ android studio ที่เชื่อมต่อกับ back4app อุปกรณ์ (หรือ อุปกรณ์เสมือน ) ที่รัน android 4 1 (jelly bean) หรือใหม่กว่า เป้าหมาย สำรวจ parsequery parsequery คลาส วิธีการต่างๆ และเรียนรู้ประเภทของการค้นหาที่คุณสามารถสร้างได้บน android คลาส parsequery การดำเนินการค้นหาใด ๆ บน parse ใช้ parsequery parsequery ประเภทวัตถุ ซึ่งจะช่วยให้คุณดึงข้อมูลเฉพาะจาก back4app ตลอดทั้งแอปของคุณ เพื่อสร้าง parsequery parsequery , คุณต้องส่งพารามิเตอร์เป็น parsequery parsequery ซับคลาสที่ต้องการ ซึ่งจะเป็นตัวที่เก็บผลลัพธ์การค้นหาของคุณ สิ่งสำคัญคือต้องรู้ว่า parsequery parsequery จะถูกแก้ไขหลังจากเรียกใช้วิธีการดึงข้อมูล (เช่น parsequery find parsequery find หรือ parsequery get parsequery get ), ดังนั้นการค้นหาสามารถตั้งค่าและมีการปรับแต่งหลายอย่างก่อนที่จะถูกเรียกใช้งานจริง คุณสามารถอ่านเพิ่มเติมเกี่ยวกับ parsequery parsequery คลาส ที่นี่ในเอกสารทางการ https //parseplatform org/parse sdk android/api/ การใช้ js console บน back4app ภายในแดชบอร์ดแอปพลิเคชัน back4app ของคุณ คุณจะพบกับ api console ที่มีประโยชน์มากซึ่งคุณสามารถรันโค้ด javascript ได้โดยตรง ในคู่มือนี้คุณจะใช้เพื่อจัดเก็บและค้นหาวัตถุข้อมูลจาก back4app ในแดชบอร์ดหลักของแอปของคุณไปที่ core >api console >js console core >api console >js console บันทึกวัตถุข้อมูลของคุณ ในการรันคำค้นในคู่มือนี้คุณจะต้องเติมข้อมูลในแอปของคุณก่อน มาสร้างคลาสตัวอย่างที่เรียกว่า profile profile , ซึ่งเลียนแบบคลาสโปรไฟล์โซเชียลมีเดียโดยใช้ชื่อของคนดังและฟิลด์ต่อไปนี้ ประเภทสตริง ประเภทวันที่ ประเภทหมายเลข (จำนวนเต็ม) ประเภทอาร์เรย์ (อาร์เรย์สตริง) ประเภทอาร์เรย์ (อาร์เรย์หมายเลข) ประเภท geopoint ประเภทพอยเตอร์ที่สามารถเป็นค่า null ได้ นี่คือ parse object parse object โค้ดการสร้างคลาส ดังนั้นไปข้างหน้าและรันมันในคอนโซล api ของคุณ 1 // add profile objects and create table 2 // adam sandler 3 let profile = new parse object('profile'); 4 profile set('name', 'adam sandler'); 5 profile set('birthday', new date('09/09/1966')); 6 profile set('friendcount', 2); 7 profile set('favoritefoods', \['lobster', 'bread']); 8 profile set('luckynumbers', \[2, 7]); 9 profile set('lastloginlocation', new parse geopoint(37 38412167489413, 122 01268034622319)); 10 await profile save(); 11 12 // britney spears 13 profile = new parse object('profile'); 14 profile set('name', 'britney spears'); 15 profile set('birthday', new date('12/02/1981')); 16 profile set('friendcount', 52); 17 profile set('favoritefoods', \['cake', 'bread']); 18 profile set('luckynumbers', \[22, 7]); 19 profile set('lastloginlocation', new parse geopoint(37 38412167489413, 122 01268034622319)); 20 await profile save(); 21 22 // carson kressley 23 profile = new parse object('profile'); 24 profile set('name', 'carson kressley'); 25 profile set('birthday', new date('11/11/1969')); 26 profile set('friendcount', 12); 27 profile set('favoritefoods', \['fish', 'cookies']); 28 profile set('luckynumbers', \[8, 2]); 29 profile set('lastloginlocation', new parse geopoint(37 38412167489413, 122 01268034622319)); 30 await profile save(); 31 32 // dan aykroyd 33 // creates related object membership for this user only 34 let membership = new parse object('membership'); 35 membership set('name', 'premium'); 36 membership set('expirationdate', new date('10/10/2030')) 37 await membership save(); 38 profile = new parse object('profile'); 39 profile set('name', 'dan aykroyd'); 40 profile set('birthday', new date('07/01/1952')); 41 profile set('friendcount', 66); 42 profile set('favoritefoods', \['jam', 'peanut butter']); 43 profile set('luckynumbers', \[22, 77]); 44 profile set('lastloginlocation', new parse geopoint(37 38412167489413, 122 01268034622319)); 45 profile set('premiummembership', membership); 46 await profile save(); 47 48 // eddie murphy 49 profile = new parse object('profile'); 50 profile set('name', 'eddie murphy'); 51 profile set('birthday', new date('04/03/1961')); 52 profile set('friendcount', 49); 53 profile set('favoritefoods', \['lettuce', 'pepper']); 54 profile set('luckynumbers', \[6, 5]); 55 profile set('lastloginlocation', new parse geopoint( 27 104919974838154, 52 61428045237739)); 56 await profile save(); 57 58 // fergie 59 profile = new parse object('profile'); 60 profile set('name', 'fergie'); 61 profile set('birthday', new date('03/27/1975')); 62 profile set('friendcount', 55); 63 profile set('favoritefoods', \['lobster', 'shrimp']); 64 profile set('luckynumbers', \[13, 7]); 65 profile set('lastloginlocation', new parse geopoint( 27 104919974838154, 52 61428045237739)); 66 await profile save(); 67 68 console log('success!'); หลังจากรันโค้ดนี้ คุณควรมี โปรไฟล์ โปรไฟล์ คลาสในฐานข้อมูลของคุณที่มีวัตถุหกตัวถูกสร้างขึ้น คลาสใหม่ของคุณควรมีลักษณะดังนี้ ตอนนี้เรามาดูตัวอย่างจากทุก parsequery parsequery เมธอด พร้อมกับคำอธิบายสั้น ๆ ว่าพวกมันทำอะไร โปรดทราบว่าบางเมธอดในรายการนี้สามารถรับ ตัวเลือก ตัวเลือก เป็นอาร์กิวเมนต์เพิ่มเติม แต่ในกรณีส่วนใหญ่จะเกี่ยวข้องกับ masterkey masterkey การใช้งานและไม่เกี่ยวข้องกับเนื้อหาของคู่มือนี้ ดังนั้นความเป็นไปได้นี้จะถูกละเว้นเมื่อไม่เกี่ยวข้อง ตัวดึงข้อมูลคำถาม วิธีการเหล่านี้มีหน้าที่ในการรันคำถามและดึงผลลัพธ์ของมัน โดยจะต้องมีอยู่เสมอในการใช้งานคำถามของคุณ นี่คือ java วิธีการ cancel //cancels the current network request 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query findinbackground(); 3 query cancel(); count //retrieves the count of parseobject results that meet the query criteria 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 try { 3 int querycount = query count(); 4 log d(tag, "count " + querycount); 5 } catch (com parse parseexception parseexception) { 6 parseexception printstacktrace(); 7 } find //this is the basic method for retrieving your query results, always returning an array of parseobject instances, being empty when none are found 1 //this find function works synchronously 2 parsequery\<parseobject> query = new parsequery<>("profile"); 3 try { 4 list\<parseobject> list = query find(); 5 log d(tag, "list " + list); 6 } catch (com parse parseexception e) { 7 e printstacktrace(); 8 } findinbackground //this is the basic method for retrieving your query results, always returning an array of parseobject instances, being empty when none are found 1 //this find function works asynchronously 2 parsequery\<parseobject> query = new parsequery<>("profile"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parseerror ", e); 8 } 9 }); first //retrieves the first parseobject instance that meets the query criteria 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 try { 3 parseobject firstitem = query getfirst(); 4 log d(tag, "first item " + firstitem); 5 } catch (parseexception e) { 6 e printstacktrace(); 7 } get //this quick method is used to retrieve a single parseobject instance when you know its objectid 1 //we can call a parse object with an object id with the get() function 2 parsequery\<parseobject> query = new parsequery<>("profile"); 3 try { 4 parseobject object = query get("c6endlnfdq"); 5 log d(tag, "object " + object); 6 } catch (parseexception e) { 7 e printstacktrace(); 8 } นี่คือ kotlin วิธีการ cancel //cancels the current network request 1 val query = parsequery\<parseobject>("profile") 2 query findinbackground() 3 query cancel() count //retrieves the count of parseobject results that meet the query criteria 1 val query = parsequery\<parseobject>("profile") 2 try { 3 val querycount = query count() 4 log d(companion tag, "count $querycount") 5 } catch (parseexception parseexception) { 6 parseexception printstacktrace() 7 } find //this is the basic method for retrieving your query results, always returning an array of parseobject instances, being empty when none are found 1 //this find function works synchronously 2 val query = parsequery\<parseobject>("profile") 3 try { 4 val list = query find() 5 log d(companion tag, "list $list") 6 } catch (e parseexception) { 7 e printstacktrace() 8 } findinbackground //this is the basic method for retrieving your query results, always returning an array of parseobject instances, being empty when none are found 1 //this find function works asynchronously 2 val query = parsequery\<parseobject>("profile") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parseerror ", e) 8 } 9 } first //retrieves the first parseobject instance that meets the query criteria 1 val query = parsequery\<parseobject>("profile") 2 try { 3 val firstitem = query first 4 log d(companion tag, "first item $firstitem") 5 } catch (e parseexception) { 6 e printstacktrace() 7 } get //this quick method is used to retrieve a single parseobject instance when you know its objectid 1 //we can call a parse object with an object id with the get() function 2 val query = parsequery\<parseobject>("profile") 3 try { 4 val `object` = query\["c6endlnfdq"] 5 log d(companion tag, "object $`object`") 6 } catch (e parseexception) { 7 e printstacktrace() 8 } เงื่อนไขการค้นหา วิธีการเหล่านี้ให้คุณมีความสามารถในการใช้ข้อจำกัดตามเงื่อนไขกับการค้นหาของคุณ ซึ่งถือเป็นการดำเนินการที่สำคัญที่สุดในการค้นหา จำไว้ว่าการดำเนินการเหล่านี้สามารถเชื่อมโยงกันได้ก่อนที่จะดึงผลลัพธ์ ดังนั้นจึงสามารถสร้างการรวมกันมากมายเพื่อแก้ไขความต้องการในการค้นหาของคุณได้ นี่คือ java วิธีการ containedin //filters objects in which a key value is contained in the provided array of values 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherecontainedin("luckynumbers", list of(2, 7)); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); contains //filters objects in which a string key value contains the provided text value be aware that this condition is case sensitive 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherecontains("name", "da"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); cointansall //filters objects in which an array type key value must contain every value provided 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherecontainsall("luckynumbers", list of(2, 7)); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); containsallstartingwith //filters objects in which an array type key value must contain every string value provided 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherecontainsallstartswith("favoritefoods", list of("shrimp", "lobster")); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); doesnotexist //filters objects in which a key value is not set 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wheredoesnotexist("premiummembership"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); นี่คือ kotlin วิธีการ containedin //filters objects in which a key value is contained in the provided array of values 1 val query = parsequery\<parseobject>("profile") 2 query wherecontainedin("luckynumbers", java util list of(2, 7)) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } contains //filters objects in which a string key value contains the provided text value be aware that this condition is case sensitive 1 val query = parsequery\<parseobject>("profile") 2 query wherecontains("name", "da") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } cointansall //filters objects in which an array type key value must contain every value provided 1 val query = parsequery\<parseobject>("profile") 2 query wherecontainsall("luckynumbers", java util list of(2, 7)) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } containsallstartingwith //filters objects in which an array type key value must contain every string value provided 1 val query = parsequery\<parseobject>("profile") 2 query wherecontainsallstartswith("favoritefoods", java util list of("shrimp", "lobster")) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } doesnotexist //filters objects in which a key value is not set 1 val query = parsequery\<parseobject>("profile") 2 query wheredoesnotexist("premiummembership") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } นี่คือ java วิธีการ canceldoesnotmatchkeyinquery //requires that a key’s value does not match a value in an object returned by a different parsequery useful for multi object querying 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 parsequery\<parseobject> innerquery = new parsequery<>("profile"); 3 innerquery wherelessthan("friendcount", 50); 4 query wheredoesnotmatchkeyinquery("friendcount", "friendcount", innerquery); 5 query wheregreaterthan("friendcount", 10); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); doesnotmatchquery //requires that an object contained in the given key does not match another query useful for multi object querying 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 parsequery\<parseobject> innerquery = new parsequery<>("membership"); 3 innerquery wheregreaterthan("expirationdate", new date()); 4 query whereexists("premiummembership"); 5 query wheredoesnotmatchquery("premiummembership", innerquery); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); endswith //filters objects in which a string key’s value ends with the provided text value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query whereendswith("name", "ie"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); equalto //filters objects in which a specific key’s value is equal to the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query whereequalto("friendcount", 2); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); exists //filters objects in which a key value is set 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query whereexists("premiummembership"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); fulltext //filters objects in which a string key’s value wrap matches the provided text value in it it can have many customizable options to improve its results, like language specification and score order 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherefulltext("name", "spears"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); greaterthan //filters objects in which a specific key’s value is greater than the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 calendar calendar = calendar getinstance(); 3 calendar set(1980, 8, 19, 59, 59, 59); 4 date date = calendar gettime(); 5 query wheregreaterthan("birthday", date); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); greaterthanorequalto //filters objects in which a specific key’s value is greater than or equal to the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wheregreaterthanorequalto("friendcount", 49); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); นี่คือ kotlin วิธีการ canceldoesnotmatchkeyinquery //requires that a key’s value does not match a value in an object returned by a different parsequery useful for multi object querying 1 val query = parsequery\<parseobject>("profile") 2 val innerquery = parsequery\<parseobject>("profile") 3 innerquery wherelessthan("friendcount", 50) 4 query wheredoesnotmatchkeyinquery("friendcount", "friendcount", innerquery) 5 query wheregreaterthan("friendcount", 10) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } doesnotmatchquery //requires that an object contained in the given key does not match another query useful for multi object querying 1 val query = parsequery\<parseobject>("profile") 2 val innerquery = parsequery\<parseobject>("membership") 3 innerquery wheregreaterthan("expirationdate", date()) 4 query whereexists("premiummembership") 5 query wheredoesnotmatchquery("premiummembership", innerquery) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } endswith //filters objects in which a string key’s value ends with the provided text value 1 val query = parsequery\<parseobject>("profile") 2 query whereendswith("name", "ie") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } equalto //filters objects in which a specific key’s value is equal to the provided value 1 val query = parsequery\<parseobject>("profile") 2 query whereequalto("friendcount", 2) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } exists //filters objects in which a key value is set 1 val query = parsequery\<parseobject>("profile") 2 query whereexists("premiummembership") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } fulltext //filters objects in which a string key’s value wrap matches the provided text value in it it can have many customizable options to improve its results, like language specification and score order 1 val query = parsequery\<parseobject>("profile") 2 query wherefulltext("name", "spears") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } greaterthan //filters objects in which a specific key’s value is greater than the provided value 1 val query = parsequery\<parseobject>("profile") 2 val calendar = calendar getinstance() 3 calendar\[1980, 8, 19, 59, 59] = 59 4 val date = calendar time 5 query wheregreaterthan("birthday", date) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } greaterthanorequalto //filters objects in which a specific key’s value is greater than or equal to the provided value 1 val query = parsequery\<parseobject>("profile") 2 query wheregreaterthanorequalto("friendcount", 49) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } นี่คือ java วิธีการ lessthan //filters objects in which a specific key’s value is lesser than the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 calendar calendar = calendar getinstance(); 3 calendar set(1980, 8, 19, 59, 59, 59); 4 date date = calendar gettime(); 5 query wherelessthan("birthday", date); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); lessthanorequalto //filters objects in which a specific key’s value is lesser than or equal to the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherelessthanorequalto("friendcount", 49); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); matches //filters objects in which a string type key value must match the provided regular expression and its modifiers 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherematches("name", "da", "i"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); matcheskeyinquery //requires that a key’s value matches a value in an object returned by a different parsequery useful for multi object querying 1 parsequery\<parseobject> query = new parsequery<>("profile"); 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 parsequery\<parseobject> innerquery = new parsequery<>("profile"); 3 innerquery wherelessthan("friendcount", 50); 4 query wherematcheskeyinquery("friendcount", "friendcount", innerquery); 5 query wheregreaterthan("friendcount", 10); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); matchesquery //requires that an object contained in the given key matches another query useful for multi object querying 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 parsequery\<parseobject> innerquery = new parsequery<>("membership"); 3 innerquery wheregreaterthan("expirationdate", new date()); 4 query whereexists("premiummembership"); 5 query wherematchesquery("premiummembership", innerquery); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 }); notequalto //filters objects in which a specific key’s value is not equal to the provided value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherenotequalto("friendcount", 2); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); startswith //filters objects in which a string key’s value starts with the provided text value 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherestartswith("name", "brit"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); นี่คือ kotlin วิธีการ lessthan //filters objects in which a specific key’s value is lesser than the provided value 1 val query = parsequery\<parseobject>("profile") 2 val calendar = calendar getinstance() 3 calendar\[1980, 8, 19, 59, 59] = 59 4 val date = calendar time 5 query wherelessthan("birthday", date) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } lessthanorequalto //filters objects in which a specific key’s value is lesser than or equal to the provided value 1 val query = parsequery\<parseobject>("profile") 2 query wherelessthanorequalto("friendcount", 49) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } matches //filters objects in which a string type key value must match the provided regular expression and its modifiers 1 val query = parsequery\<parseobject>("profile") 2 query wherematches("name", "da", "i") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } matcheskeyinquery //requires that a key’s value matches a value in an object returned by a different parsequery useful for multi object querying 1 parsequery\<parseobject> query = new parsequery<>("profile"); 1 val query = parsequery\<parseobject>("profile") 2 val innerquery = parsequery\<parseobject>("profile") 3 innerquery wherelessthan("friendcount", 50) 4 query wherematcheskeyinquery("friendcount", "friendcount", innerquery) 5 query wheregreaterthan("friendcount", 10) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } matchesquery //requires that an object contained in the given key matches another query useful for multi object querying 1 val query = parsequery\<parseobject>("profile") 2 val innerquery = parsequery\<parseobject>("membership") 3 innerquery wheregreaterthan("expirationdate", date()) 4 query whereexists("premiummembership") 5 query wherematchesquery("premiummembership", innerquery) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } notequalto //filters objects in which a specific key’s value is not equal to the provided value 1 val query = parsequery\<parseobject>("profile") 2 query wherenotequalto("friendcount", 2) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } startswith //filters objects in which a string key’s value starts with the provided text value 1 val query = parsequery\<parseobject>("profile") 2 query wherestartswith("name", "brit") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } การจัดลำดับคำถาม สิ่งจำเป็นในคำถามส่วนใหญ่ การจัดเรียงสามารถทำได้ง่ายใน parse และแม้กระทั่งเชื่อมโยงระหว่างข้อจำกัดการจัดเรียงสองข้อหรือมากกว่า นี่คือ java วิธีการ addascending //sort the results in ascending order, overwrites previous orderings multiple keys can be used to solve ordering ties 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query addascendingorder("friendcount"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); adddescending //sort the results in descending order, overwrites previous orderings multiple keys can be used to solve ordering ties 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query adddescendingorder("friendcount"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); ascending //sort the results in ascending order, this can be chained without overwriting previous orderings multiple keys can be used to solve ordering ties 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query orderbyascending("friendcount"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); descending //sort the results in descending order, this can be chained without overwriting previous orderings multiple keys can be used to solve ordering ties 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query orderbydescending("friendcount"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); นี่คือ kotlin วิธีการ addascending //sort the results in ascending order, overwrites previous orderings multiple keys can be used to solve ordering ties 1 val query = parsequery\<parseobject>("profile") 2 query addascendingorder("friendcount") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } adddescending //sort the results in descending order, overwrites previous orderings multiple keys can be used to solve ordering ties 1 val query = parsequery\<parseobject>("profile") 2 query adddescendingorder("friendcount") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } ascending //sort the results in ascending order, this can be chained without overwriting previous orderings multiple keys can be used to solve ordering ties 1 val query = parsequery\<parseobject>("profile") 2 query orderbyascending("friendcount") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } descending //sort the results in descending order, this can be chained without overwriting previous orderings multiple keys can be used to solve ordering ties 1 val query = parsequery\<parseobject>("profile") 2 query orderbydescending("friendcount") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } การเลือกฟิลด์ วิธีการเหล่านี้มีผลต่อค่าฟิลด์ที่สามารถอยู่ในผลลัพธ์ของการค้นหาของคุณ นี่คือ java วิธีการ include //return all fields in the returned objects except the ones specified 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query whereexists("premiummembership"); 3 query include("premiummembership"); 4 query findinbackground((objects, e) > { 5 if (e == null) { 6 log d(tag, "objects " + objects); 7 log d(tag, "object premium membership " + objects get(0) get("premiummembership")); 8 } else { 9 log e(tag, "parse error ", e); 10 } 11 12 }); select //return only the specified fields in the returned objects 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query selectkeys(list of("name")); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 log d(tag, "object name " + objects get(0) get("name")); 7 } else { 8 log e(tag, "parse error ", e); 9 } 10 11 }); นี่คือ kotlin วิธีการ include //return all fields in the returned objects except the ones specified 1 val query = parsequery\<parseobject>("profile") 2 query whereexists("premiummembership") 3 query include("premiummembership") 4 query findinbackground { objects list\<parseobject>, e parseexception? > 5 if (e == null) { 6 log d(companion tag, "objects $objects") 7 log d( 8 companion tag, 9 "object premium membership " + objects\[0]\["premiummembership"] 10 ) 11 } else { 12 log e(companion tag, "parse error ", e) 13 } 14 } select //return only the specified fields in the returned objects 1 val query = parsequery\<parseobject>("profile") 2 query selectkeys(java util list of("name")) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 log d(companion tag, "object name " + objects\[0]\["name"]) 7 } else { 8 log e(companion tag, "parse error ", e) 9 } 10 } การค้นหา geopoint นี่คือวิธีการเฉพาะสำหรับการค้นหา geopoint นี่คือ java วิธีการ near //order objects by how near the key value is from the given geopoint 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherenear("lastloginlocation", new parsegeopoint(37 38412167489413, 122 01268034622319)); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); polygoncontains //find objects whose key value contains the specified geopoint 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherepolygoncontains("lastloginlocation", new parsegeopoint(37 38412167489413, 122 01268034622319)); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); withingeobox //find objects whose key value is contained within the specified bounding box, composed by two geopoint values that set the lower left and upper right corner values 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherewithingeobox("lastloginlocation", new parsegeopoint(37 48412167489413, 122 11268034622319), new parsegeopoint(37 28412167489413, 121 91268034622319)); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); withinkilometers //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherewithinkilometers("lastloginlocation", new parsegeopoint(37 38412167489413, 122 01268034622319), 100); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); withinmiles //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherewithinmiles("lastloginlocation", new parsegeopoint(37 38412167489413, 122 01268034622319), 100); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); withinpolygon //find objects whose key value is contained within the specified polygon, composed of an array of geopoints (at least three) if the polygon path is open, it will be closed automatically by parse connecting the last and first points 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherewithinpolygon("lastloginlocation", list of(new parsegeopoint(37 48412167489413, 122 11268034622319), 3 new parsegeopoint(37 48412167489413, 121 91268034622319), 4 new parsegeopoint(37 28412167489413, 121 91268034622319), 5 new parsegeopoint(37 28412167489413, 122 01268034622319))); 6 query findinbackground((objects, e) > { 7 if (e == null) { 8 log d(tag, "objects " + objects); 9 } else { 10 log e(tag, "parse error ", e); 11 } 12 13 }); withinradians //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query wherewithinradians("lastloginlocation", new parsegeopoint(37 38412167489413, 122 01268034622319), 100); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); นี่คือ kotlin วิธีการ near //order objects by how near the key value is from the given geopoint 1 val query = parsequery\<parseobject>("profile") 2 query wherenear("lastloginlocation", parsegeopoint(37 38412167489413, 122 01268034622319)) 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } polygoncontains //find objects whose key value contains the specified geopoint 1 val query = parsequery\<parseobject>("profile") 2 query wherepolygoncontains( 3 "lastloginlocation", 4 parsegeopoint(37 38412167489413, 122 01268034622319) 5 ) 6 query findinbackground { objects list\<parseobject>, e parseexception? > 7 if (e == null) { 8 log d(companion tag, "objects $objects") 9 } else { 10 log e(companion tag, "parse error ", e) 11 } 12 } withingeobox //find objects whose key value is contained within the specified bounding box, composed by two geopoint values that set the lower left and upper right corner values 1 val query = parsequery\<parseobject>("profile") 2 query wherewithingeobox( 3 "lastloginlocation", 4 parsegeopoint(37 48412167489413, 122 11268034622319), 5 parsegeopoint(37 28412167489413, 121 91268034622319) 6 ) 7 query findinbackground { objects list\<parseobject>, e parseexception? > 8 if (e == null) { 9 log d(companion tag, "objects $objects") 10 } else { 11 log e(companion tag, "parse error ", e) 12 } 13 } withinkilometers //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 val query = parsequery\<parseobject>("profile") 2 query wherewithinkilometers( 3 "lastloginlocation", 4 parsegeopoint(37 38412167489413, 122 01268034622319), 5 100 0 6 ) 7 query findinbackground { objects list\<parseobject>, e parseexception? > 8 if (e == null) { 9 log d(companion tag, "objects $objects") 10 } else { 11 log e(companion tag, "parse error ", e) 12 } 13 } withinmiles //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 val query = parsequery\<parseobject>("profile") 2 query wherewithinmiles( 3 "lastloginlocation", 4 parsegeopoint(37 38412167489413, 122 01268034622319), 5 100 0 6 ) 7 query findinbackground { objects list\<parseobject>, e parseexception? > 8 if (e == null) { 9 log d(companion tag, "objects $objects") 10 } else { 11 log e(companion tag, "parse error ", e) 12 } 13 } withinpolygon //find objects whose key value is contained within the specified polygon, composed of an array of geopoints (at least three) if the polygon path is open, it will be closed automatically by parse connecting the last and first points 1 val query = parsequery\<parseobject>("profile") 2 query wherewithinpolygon( 3 "lastloginlocation", java util list of( 4 parsegeopoint(37 48412167489413, 122 11268034622319), 5 parsegeopoint(37 48412167489413, 121 91268034622319), 6 parsegeopoint(37 28412167489413, 121 91268034622319), 7 parsegeopoint(37 28412167489413, 122 01268034622319) 8 ) 9 ) 10 query findinbackground { objects list\<parseobject>, e parseexception? > 11 if (e == null) { 12 log d(companion tag, "objects $objects") 13 } else { 14 log e(companion tag, "parse error ", e) 15 } 16 } withinradians //find objects whose key value is near the given geopoint and within the maxdistance value the sorted boolean value determines if the results should be sorted by distance ascending 1 val query = parsequery\<parseobject>("profile") 2 query wherewithinradians( 3 "lastloginlocation", 4 parsegeopoint(37 38412167489413, 122 01268034622319), 5 100 0 6 ) 7 query findinbackground { objects list\<parseobject>, e parseexception? > 8 if (e == null) { 9 log d(companion tag, "objects $objects") 10 } else { 11 log e(companion tag, "parse error ", e) 12 } 13 } การแบ่งหน้า วิธีการเหล่านี้เกี่ยวข้องกับเครื่องมือการแบ่งหน้า ซึ่งมีประโยชน์สำหรับการค้นหาที่จะดึงข้อมูลผลลัพธ์จำนวนมาก นี่คือ java วิธีการ limit //sets the maximum value of returned results, the default value is 100 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query setlimit(2); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); skip //skips the first n results in the query, essential for pagination 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query setskip(2); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); นี่คือ kotlin วิธีการ limit //sets the maximum value of returned results, the default value is 100 1 val query = parsequery\<parseobject>("profile") 2 query limit = 2 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } skip //skips the first n results in the query, essential for pagination 1 val query = parsequery\<parseobject>("profile") 2 query skip = 2 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } ฐานข้อมูลท้องถิ่น วิธีการเหล่านี้ช่วยให้เลือกแหล่งที่มาของการค้นหาและใช้ฐานข้อมูลท้องถิ่น นี่คือ java วิธีการ fromlocaldatastore //changes the source of this query to all pinned objects 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 //if you want use localdatastore you should enable local data store in the app java or app kt file 3 query fromlocaldatastore(); 4 query findinbackground((objects, e) > { 5 if (e == null) { 6 log d(tag, "objects " + objects); 7 } else { 8 log e(tag, "parse error ", e); 9 } 10 11 }); fromnetwork //changes the source of this query to your online server 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query fromnetwork(); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); frompin //changes the source of this query to the default group of pinned objects 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query frompin(); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 10 }); frompinwithname //changes the source of this query to a specific group of pinned objects 1 parsequery\<parseobject> query = new parsequery<>("profile"); 2 query frompin("pinnedobjects"); 3 query findinbackground((objects, e) > { 4 if (e == null) { 5 log d(tag, "objects " + objects); 6 } else { 7 log e(tag, "parse error ", e); 8 } 9 }); นี่คือ kotlin วิธีการ fromlocaldatastore //changes the source of this query to all pinned objects 1 val query = parsequery\<parseobject>("profile") 2 //if you want use localdatastore you should enable local data store in the app java or app kt file 3 query fromlocaldatastore() 4 query findinbackground { objects list\<parseobject>, e parseexception? > 5 if (e == null) { 6 log d(companion tag, "objects $objects") 7 } else { 8 log e(companion tag, "parse error ", e) 9 } 10 } fromnetwork //changes the source of this query to your online server 1 val query = parsequery\<parseobject>("profile") 2 query fromnetwork() 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } frompin //changes the source of this query to the default group of pinned objects 1 val query = parsequery\<parseobject>("profile") 2 query frompin() 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } frompinwithname //changes the source of this query to a specific group of pinned objects 1 val query = parsequery\<parseobject>("profile") 2 query frompin("pinnedobjects") 3 query findinbackground { objects list\<parseobject>, e parseexception? > 4 if (e == null) { 5 log d(companion tag, "objects $objects") 6 } else { 7 log e(companion tag, "parse error ", e) 8 } 9 } บทสรุป ในตอนท้ายของคู่มือนี้ คุณได้เรียนรู้วิธีการใช้ประเภทคำค้นหาที่แตกต่างกันใน android