解析：如何设置一个指针的Andr​​oid？ [英] Parse: How to set a pointer in Android?

问题描述

在我目前的类，比方说，我有一列是一个指向另一个类，说B.任何人都可以请让我知道我可以在Android的此列？

In my current class, say A, I have a column which is a pointer to another class, say B. Can anyone please let me know how I can set a value for this column in Android?

我曾尝试获取来自B类要求的行作为的parseObject，并做了：

I have tried fetching the required row from class B as a ParseObject, and doing a:

classAObject.put("column_name",classBParseObject);

不过，这只是我的A级创建一个空行，没有指针。在这方面的任何帮助是非常AP preciated。

But, this is just creating an empty row in my class A, with no pointers. Any help in this regard is much appreciated.

推荐答案

如果您有计算机科学课程ID的OBJECTID，那么你需要使用createWithoutData方法保存。因此，让我们回顾一下：你有一个叫CourseId列学生表 - 这是一个指向课程表，而不是课程表的CourseId列。你不能指向一个栏，你点到一个表。

If you have the objectID of the course ID for Computer Science, then you need to save using the createWithoutData method. So let's recap: You have a Student table with a column called CourseId - that is a pointer to the Course table, not the CourseId column of the Course table. You can't point to a column, you point to a table.

所以，当你创建一个新的Student对象，你需要一个指针保存到计算机科学的CourseId列。比方说计算机科学对象在你的课程表中的OBJECTID是XYZ123。你会做到以下几点：

So when you create a new Student object, you need to save a pointer into the CourseId column for Computer Science. Let's say the objectID of the Computer Science object in your Course table is "xyz123". You would do the following:

ParseObject student = new ParseObject("Student");
student.put("CourseId", ParseObject.createWithoutData("Course", "xyz123");
//...set other values for the student object
student.saveInBackground();

在解析文档有你需要什么，并更多 - 退房关系数据的部分：
<一href=\"https://parse.com/docs/android_guide#objects-pointers\">https://parse.com/docs/android_guide#objects-pointers

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