guidata (MATLAB Function Reference)

Store or retrieve application data

Syntax

guidata(object_handle,data)
data = guidata(object_handle)

Description

guidata(object_handle,data) stores the specified data in the figure's application data. If object_handle is not a figure handle, then the object's parent figure is used.

data = guidata(object_handle) returns previously stored data, or an empty matrix if nothing has been stored.

guidata provides application developers with a convenient interface to a figure's application data:

You do not need to create and maintain a hard-coded property name for the application data throughout your source code.
You can access the data from within a subfunction callback routine using the component's handle (which is returned by gcbo), without needing to find the figure's handle.

guidata is particularly useful in conjunction with guihandles, which creates a structure in the figure's application data containing the handles of all the components in a GUI.

Examples

In this example, guidata is used to save a structure on a GUI figure's application data from within the initialization section of the application M-file. This structure is initially created by guihandles and then used to save additional data as well.

data = guihandles(figure_handle); % create structure of handles
data.numberOfErrors = 0; % add some additional data
guidata(figure_handle,data) % save the structure

You can recall the data from within a subfunction callback routine and then save the structure again:

data = guidata(gcbo); % get the structure in the subfunction
data.numberOfErrors = data.numberOfErrors + 1;
guidata(gcbo,data) % save the changes to the structure

gtext guide