Get the "handle number" of a standard handle class

2012 2 29
4 个回答
回答已采纳
2 次查看（30 天）

1 个投票

How can I ...
-Get the "handle number" (like the handle number returned when using hdgetset classes(ex : 203.0024)) of a myclass object which is of a "standard" handle class (myclass<handle)
-Store this "handle number" in a text variant
-And then retrieve my original object by this "handle number"
Thanks for you help!!! Gabriel

请先登录，再回答此问题。

 采纳的回答

Walter Roberson
Walter Roberson 2012-2-29

1 个投票

You can attach arbitrary (binary) data to a graphics object by setting its UserData property, or by using setappdata() on it.

更多回答（3 个）

Andrew Newell
Andrew Newell 2012-2-29

1 个投票

Setappdata seems best because of the limitations on using the UserData property (see How can I keep track of my GUI object handles?. You can store handles, as in the following example:
x = 1:10;
h = plot(x,x);
ha = @(x) x^2;
setappdata(h,'myHandle',ha)
f = getappdata(h,'myHandle');
f(2)
ans =
4
Daniel Shub
Daniel Shub 2012-2-29

0 个投票

You cannot do this directly. I don't understand why you would want to. Why not just pass the object around? MATLAB is pretty smart about memory management and doesn't make copies of handle object every time they are referenced.
If you really want to do it, you could subclass the handle class with something like myhandle. This new class could have a public property "h" which gets set at creation with a unique number. There are a number of ways that I can think of to keep track of the handle number to guarantee that they are unique. Then just make myclass<myhandle.

6 个评论
显示 4更早的评论 隐藏 4更早的评论

Walter Roberson
Walter Roberson 2012-2-29
I _think_ what Gabriel is asking for is an object serialization method. Which MATLAB does have internally but has never exposed.
Daniel Shub
Daniel Shub 2012-2-29
@Walter, it is possible that I am wrong. I interpreted hdgetset to be hgsetget and the 203.0024 to be a handle to a graphics object.
Walter Roberson
Walter Roberson 2012-2-29
Hard to say. We'll have to wait for an update from Gabriel.
I am building a mass transit simulation interface. The user use tools to build the mass transit system over an image. What I need is to make a link between the graphic objects (lines, etc.) and the "simulation objects" they represent(tracks, stations, etc.). The only way that I have found to store information into a graphic object is by changing their Tag property. The problem is that the Tag property only accept text. I don't want to store the graphic objects into my "simulation objects". If you have an alternate method to arrive to that goal, it could also solve my problem. Thanks.
So my question was basically if an object of class Myclass<handle have a handle that can be retrieved and used to retrieve back this object like the graphics objects have.
Walter Roberson
Walter Roberson 2012-2-29
Gabriel, object handles that are not handle graphics objects, do *not* have a representation of the kind you are seeking.

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Creating, Deleting, and Querying Graphics Objects 的更多信息

产品

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by