FindJObj - find java handles of Matlab graphic objects

Find java objects contained within a specified java container or Matlab GUI handle

Description

Find all java objects contained within a java container or Matlab GUI handle

If no output parameter is specified, then an interactive GUI window will be displayed with a tree-view of all container components, their properties and callbacks.

Syntax:
[handles,levels,parentIds,listing] = findjobj(container,'PropName',PropValue(s),...)
 
Inputs:
- container - optional GUI handle. If unsupplied then current figure will be used
- 'PropName',PropValue - optional list of case insensitive property pairs. PropName may also be named -PropName. Supported properties:
  - 'position' - filter results based on those elements that contain the specified X,Y position or a java element
        Note: specify a Matlab position (X,Y = pixels from bottom left corner), not a java one
  - 'size' - filter results based on those elements that have the specified W,H (in pixels)
  - 'class' - filter results based on those elements that contain the substring (or java class) PropValue
        Note: filtering is case insensitive and relies on regexp, so you can pass wildcards etc.
  - 'property' - filter results based on elements that possess the specified case-insensitive property string or have property values in cell array format: {'propName', 'propValue'}. Example: findjobj(...,'property', {'Text','click me'})
  - 'depth' - filter results based on specified depth. 0=top-level, Inf=all levels (default=Inf)
  - 'flat' - same as: 'depth',0
  - 'not' - negates the following filter: 'not','class','c' returns all elements EXCEPT those with class 'c'
  - 'persist' - persist figure components information, allowing much faster results for subsequent invocations
  - 'print' - display all java elements in a hierarchical list
        Note1: optional PropValue of element index or handle to java container
        Note2: normally this option would be placed last, after all filtering is complete.
  - 'list' - same as 'print'
 
Outputs:
- handles - list of handles to java elements
- levels - list of corresponding hierarchy level of the java elements (top=0)
- parentIds - list of indexes (in unfiltered handles) of the parent container of the corresponding java element
- listing - results of 'print'/'list' options (empty if 'print'/'list' were unspecified)

Sample usage:
>> hButton = uicontrol('string','click me');
>> jButton = findjobj(hButton,'nomenu'); % or: jButton = findjobj('property',{'Text','click me'});
>> jButton.setFlyOverAppearance(1);
>> jButton.setCursor(java.awt.Cursor.getPredefinedCursor(java.awt.Cursor.HAND_CURSOR));
>> set(jButton,'FocusGainedCallback',@myMatlabFunction); % some 30 callback points available...
>> jButton.get; % list all changeable properties...

>> hEditbox = uicontrol('style',edit');
>> jEditbox = findjobj(hEditbox,'nomenu');
>> jEditbox.setCaretColor(java.awt.Color.red);
>> jEditbox.KeyTypedCallback = @myCallbackFunc; % many more callbacks where this came from...
>> jEdit.requestFocus;

(Many more examples in the utility's help section)
 
Known issues/limitations:
- Cannot currently process multiple container objects - just one at a time
- Initial processing is a bit slow when the figure is laden with many UI components (so better use 'persist')
- Passing a container Matlab handle is currently found by position+size: should find a better way to do this
- Matlab uipanels are not implemented as simple java panels, and so they can't be found using this utility
- Labels have a write-only text property in java, so can't be found using 'property',{'Text','string'} notation

Technical description:
http://UndocumentedMatlab.com/blog/findjobj-find-underlying-java-object/
http://UndocumentedMatlab.com/blog/findjobj-gui-display-container-hierarchy/
 
Warning:
This code heavily relies on undocumented and unsupported Matlab functionality. It works on Matlab 7+, but use at your own risk!
 
Bugs and suggestions:
Please send to Yair Altman (altmany at gmail dot com)

See also:
java, handle, findobj, findall

Acknowledgements

Uiinspect Display Methods Properties Callbacks Of An Object inspired this file.

This file inspired Copy Paste, Probability Distribution Plotter, Dynamic Search Box, Reorderable Listbox, Check Version Check For A Newer File Version On The File Exchange, Set Desktop Visibility, Virtual Tackball, Uhelp, Command Window Text, Enable/Disable Figure, Get J Frame Retrieves A Figure's Underlying Java Frame, Statusbar, Graphical Wrappers, Manage And Dock Figures Into Group, Colorize Document Bar, Maximize, Uiinspect Display Methods Properties Callbacks Of An Object, Tortoise Svn Toolbar Integration, and Sim.I.Am.

• MATLAB release: MATLAB 7.1.0 (R14SP3)
• Other requirements: Java should be enabled (duh!) Works on Matlab 7.1+ (reportedly also works on Matlab 7.0 but this is untested)

[Katana13]

Ok, Thank you!!!! Yair Altman

[Yair Altman]

@Katana13 - Java customizations are not saved in FIG files. See here for a discussion and workaround: http://undocumentedmatlab.com/blog/figure-toolbar-components/#comment-13897

[Katana13]

Extremely useful toolbox for creating GUIs. I don't know if it's a limitation (Matlab R2012a). Example:
h = figure('Menubar','none', 'Toolbar','none','Tag','figure');
str = ' je suis vraiment le plus beau de la planete terrrer de la foucv oeufe fz ozfz efz fvousf zefzf ouvzfz ozfz fouz fz fzo ufzf zouz fozufozf uzo fzoufzo fuziofz fzofiuzfoiz fouzfo ';
hEdit = uicontrol('Parent',h, 'Style','edit', 'FontSize',9, ...
'Min',0, 'Max',2, 'HorizontalAlignment','left', ...
'Units','normalized', 'Position',[0 0 1 1], ...
'String',str,'Tag','hEdit');

%# enable horizontal scrolling
jEdit = findjobj(hEdit);
jEditbox = jEdit.getViewport().getComponent(0);
jEditbox.setWrapping(false); %# turn off word-wrapping
jEditbox.setEditable(false); %# non-editable
set(jEdit,'HorizontalScrollBarPolicy',30); %# HORIZONTAL_SCROLLBAR_AS_NEEDED

%# maintain horizontal scrollbar policy which reverts back on component resize
hjEdit = handle(jEdit,'CallbackProperties');
set(hjEdit, 'ComponentResizedCallback','set(gcbo,''HorizontalScrollBarPolicy'',30)')

saveas(h,'test','fig');

No problem, if you directly run the script (horizontal + vertical scrollbar available). But if you launch the saved file : 'test.fig', the horizontal scrollbar becomes unavailable.

Thanks

[Raz Shimoni]

 

[Raz Shimoni]

Extremely useful function that helped me alot. Just excellent!

[Fred Holt]

Thanks for the support!

I used findjobj to update a table position, and it works well, but there are some rendering artifacts as a result of the update - hopefully seen here: http://imgur.com/uJYps3Y .
Apologies, as I am not too familiar with java, but a simple drawnow doesn't seem to help.

[Yair Altman]

@Georgios - the control must be visible for findjobj to work. You can make the figure visible in the OpenFcn using the commands
set(hObject,'Visible','on'); drawnow;

If you don't want the figure to physically appear onscreen, you can set its position to [-300,-300,200,200] or some other off-screen location. The figure will become visible but hidden... You can later move it to your screen center in the OutputFcn.

[Voulgarakis Georgios]

Hallo and congrats for the excellent code!

My issue is the following:
I need to use the findjobj, before the uicontrol is properly rendered.
Is there a way to achieve this?

(I need to set some attributes of the uicotnrol, in the OpenFcn function of the GUI.) Which means that the uicontrols are not yet rendered.

[Yair Altman]

@Echidna - findjobj works out-of-the-box and does not require any additional installation or file, including in deployed (compiled) apps. So I am 99.99% certain that the problem is in your code. It could be due to one of several possibilities:

1) perhaps your editbox has not become visible onscreen long enough before your call to findjobj. Findjobj must have the control visible before it can find its underlying Java component. Place calls to pause(0.1) and drawnow before your call to findjobj, to ensure that this is indeed so.

2) maybe your callback function became invalid for some reason. For example, if you modify the editbox from multi-line to single-line or other similar changes, then the underlying Java control may have changed, forcing you to re-set your callback

3) maybe your update callback is being called but runs into a bug when updating the listbox for some reason. Place debug printouts in your callback to check this.

[Echidna]

This code works great when I run my GUI directly in Matlab BUT when I compile it into an executable using deploytool, it does not always work. More specifically it works the first time I change the text in the edit box, sometimes the second time but somewhere thereafter (always at a different point), it does not seem to work anymore (i.e. no update of my listbox when I type in the edit-field and some other strange stuff sometimes happens as freezing of the list box, not finding the text string even though I know it is there and such).

Is this a known bug and how can I solve this? Is there another file that I need to include in the "Shared resources and helper files" section besides the findjobj.m file which I of course have included?

[Yair Altman]

@Peter - as far as I could test, the latest findjobj works correctly on R2012b. try running your two lines in a new figure and see for yourself. Perhaps in your specific GUI findjobj cannot find the slider control for some reason. One possible explanation is that the uicontrol is not fully rendered (displayed) when findjobj is being run. In this case, placing a short pause(0.05) and drawnow(), might help. Also ensure that the slider is actually displayed onscreen (Visible=on, valid Position and Value).

[Peter Corke]

I've used this module successfully for many years, thanks.

With R2012b I've got problems:

jh = findjobj( slider, 'nomenu');
jh.AdjustmentValueChangedCallback = @(src,event)sliderCallbackFunc(src);

and the second line results in an error

Incorrect number of right hand side elements in dot name assignment. Missing [] around left hand side is a
likely cause.

Anybody else had related problems under R2012b.

[Alexander Kosenkov]

 

[Alexander Kosenkov]

 

[Yair Altman]

@Changshun Deng - I believe that the latest version of FindJObj that I uploaded yesterday solves this issue

[Changshun Deng]

Hi, I run this programe findjobj(jEditor) as http://undocumentedmatlab.com/blog/accessing-the-matlab-editor/
I can not get the objects of editor.
an error: ??? findjobj: There is no 'UserData' property in the 'javax.swing.JTable$1' class.

my matlab version is: MATLAB Version 7.4

[Martin Lechner]

 

[Yair Altman]

@Ward - thanks - I believe that you may be right. This has no effect unless there are several overlapping/similar results in the filtering process, which is very rare. But in such rare cases, your fix would solve a problem of returning both the parent and the child handles.

[Ward]

On lines 646-649 you discard the first if in the original handles the first is the parent of second. Is this correct after Args processing or should the first line be

if length(foundIdx) > 1 && isequal(handles(foundIdx(1)).java, handles(foundIdx(2)).getParent)

[David Thompson]

This is a very cool tool, but I'm running into the same problem that Michael had - if I compile the code, I get a metric ton of "file is empty" messages. Everything works fine, it just gets in the way of other things I'd like to use the output window for. Any hope of an update to address this?

[Yair Altman]

@HaveF - you don't need to use the 'nomenu' parameter when you specify an input handle such as hButton.

I cannot reproduce any of the issues that you report. Perhaps try to download the latest version of the utilities.

Try adding a call to drawnow and/or pause(0.1) before you call findjobj. Also, ensure that the control is actually visible (findjobj can only detect visible components).

[HaveF]

seems lost something...
When I try findjobj, something strange on my machine.
>> hButton = uicontrol('string','click me'); jButton = findjobj('property',{'Text','click me'});
it's all right as I expected.
but
>> hButton = uicontrol('string','click me'); jButton = findjobj(hButton,'nomenu')
just return *ans = <1x0>*

and another thing, I am a big fun of yours.
I use setPrompt before, but when I try findjobj, my prompt disappear.
just like this:

[18:57:11]temp_proj>>
[18:57:11]temp_proj>>
[18:57:11]temp_proj>> hButton = uicontrol('string','click me');
[18:57:16]temp_proj>> jButton = findjobj('property',{'Text','click me'});
>>

[HaveF]

and another thing, I am a big fun of yours.
I use setPrompt before, but when I try findjobj, my prompt disappear.
just like this:

[18:57:11]temp_proj>>
[18:57:11]temp_proj>>
[18:57:11]temp_proj>> hButton = uicontrol('string','click me');
[18:57:16]temp_proj>> jButton = findjobj('property',{'Text','click me'});
>>

[Arturo Moncada Torres]

 

[Nik F]

Excellent!

[Nicolas]

the above code works - often ;)
sometimes it throws:

No appropriate method, property, or field getViewport for class handle.handle.

-> class handle.handle => haha

how can i assure findjobj found the table?

currently i retry on failure:

code:

function setTableSelectedCellColor(table)
%

try
jUIScrollPane = findjobj(table, 'nomenu');
jUITable = jUIScrollPane.getViewport.getView;
jUITable.setSelectionBackground(java.awt.Color(1,1,1));
jUITable.setSelectionForeground(java.awt.Color(0,0,0));
catch
setTableSelectedCellColor(table);
end

end %function

end code

[Nicolas]

Fabulous!
I use it to avoid selection induced color change for a table with white background:

code:

% create the table
table = uitable( ...
'Parent', layout,...
'ColumnWidth', {100, 150}, ...
'ColumnName', {tableTitle}, ...
'RowName', [], ...
'ColumnFormat', {'char', selectionList}, ...
'ColumnEditable', [false, true],...
'Data', tableData, ...
'CellEditCallback', @selectionChanged);

% workarount to avoid seletion induced color change
jUIScrollPane = findjobj(table);
jUITable = jUIScrollPane.getViewport.getView;
jUITable.setSelectionBackground(java.awt.Color(1,1,1));
jUITable.setSelectionForeground(java.awt.Color(0,0,0));

end code

is there a way to make the findjobj command faster?

[Luc]

 

[Yair Altman]

@Evzen - for some reason, you got the handle of a uitable rather than the editbox, and of course you cannot set the page URL for uitables...

Perhaps your uitable resides at the same pixel position as the editbox?

Try to place a breakpoint on the line following the call to findjobj to determine exactly which object it found.

More information on setting rich editbox contents can be found here: http://undocumentedmatlab.com/blog/rich-matlab-editbox-contents/

[Evzen Brusle]

Awsome utility. Thanks for sharing, but I have a little problem and i dont resolve it. I use a code from your webpage, but it give me this error with method setPage:

No appropriate method, property, or field setPage for class
com.mathworks.hg.peer.ui.UITablePeer$22.

hEditbox = uicontrol('style','edit', 'max',5);

jScrollPane = findjobj(hEditbox);
jViewPort = jScrollPane.getViewport;
jEditbox = jViewPort.getComponent(0);
jEditbox.setPage('http://www.google.com');

[Yair Altman]

@Sean - you don't need findjobj to access specific toolbar buttons - you can use the built-in findall function, as explained here: http://undocumentedmatlab.com/blog/modifying-default-toolbar-menubar-actions/

[Andrew Bytheway]

This is an awesome tool. Thanks for your sharing your work Yair.

[Sean Larkin]

I'm trying to use findjobj to get the java handle for a toolbar uitogglebutton. It does not find the handles for the button. When I call the function like this:
findjobj;

it finds the toolbar button. Why is this and is there a way I can modify findjobj to directly find toolbar buttons?

[Michael]

Works super! Nevertheless, when I compile this line:
jScrollPane = findjobj(handles.editBox)
and I execute the code, I get many times the message 'File is empty' in the command line. Anyway, the code works nevertheless!? Any ideas?

Best regards!

PS: I use your tool to extract selected text from an edit box.

[Emad Hasan]

Finally got it to work, thanks a lot for the updates!

[Urs]

Hi Guys,

I have written the following code in _OpeningFcn(because I have used GUIDE!),

pause(0.01);
drawnow;
jb=findjobj('class','pushbutton');
drawnow;
set(jb(2), 'MousePressedCallback', @UpVertTest);
guidata(hObject, handles);
--------------------

Up to here everything works fine,

But at the end of my m file where I define the related function(UpVertTest) I have problem,
I want to have access to normal handles and do some changes, But I get this error:

??? Undefined function or method 'toDouble' for input arguments of type 'java.awt.Dimension'.

Error in ==> opaque.double at 80
dbl = toDouble(opaque_array(1));

Error in ==> guidata at 85
if isscalar(h) && ishghandle(h)

Error in ==> RatRobot_GUI4>UpVertTest at 523
handlesData=guidata(src);

this is the code I have written:

function UpVertTest(src, evnt)
% trying to access to handles
handlesData=guidata(src);

% set new initial value in GUI
set(handlesData.VerticalPosStart,'string',handlesData.initZ-handles.Step(3));drawnow;
-----------

I think there is something wrong with my function definition,
any ideas?

[Oscar Hartogensis]

I used the findjobj-function as described at http://undocumentedmatlab.com/blog/customizing-listbox-editbox-scrollbars/ to disable text-wrapping and display a horizontal scroll-bar in a GUI edit-box.
Many thanks for this fabulous tool. It works like a charm.

[Jveer]

after further testing, following the use of findjobj, from time to time i get the following errors:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.text.BoxView.calculateMinorAxisRequirements(BoxView.java:886)
at javax.swing.text.html.BlockView.calculateMinorAxisRequirements(BlockView.java:129)
at javax.swing.text.BoxView.checkRequests(BoxView.java:918)
at javax.swing.text.BoxView.getPreferredSpan(BoxView.java:528)
at javax.swing.text.html.BlockView.getPreferredSpan(BlockView.java:345)
at javax.swing.plaf.basic.BasicTextUI$RootView.getPreferredSpan(BasicTextUI.java:1342)
at javax.swing.plaf.basic.BasicTextUI.getPreferredSize(BasicTextUI.java:908)
at javax.swing.JComponent.getPreferredSize(JComponent.java:1622)
at javax.swing.JEditorPane.getPreferredSize(JEditorPane.java:1412)
at com.mathworks.hg.peer.EditTextPeer$hgTextEditMultiline.getPreferredSize(EditTextPeer.java:864)
at javax.swing.ScrollPaneLayout.layoutContainer(ScrollPaneLayout.java:769)
at java.awt.Container.layout(Container.java:1421)
at java.awt.Container.doLayout(Container.java:1410)
at java.awt.Container.validateTree(Container.java:1507)
at java.awt.Container.validate(Container.java:1480)
at javax.swing.RepaintManager.validateInvalidComponents(RepaintManager.java:670)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:124)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:633)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

is there a workaround?

[Jveer]

that does make sense. thank you for clarifying that.

[Yair Altman]

Jveer - FindJObj *cannot* work in the GUIDE-created *_OpeningFcn because the figure is not yet visible at this time and so the Java components have still not rendered and therefore cannot be found.

Try placing your call to FindJObj *after* the figure has become visible and all the controls have completed rendering, for example by moving your FindJObj call to the *_OutputFcn function, hopefully after a call to drawnow to ensure that everything has completed rendering.

[Jveer]

i'm sorry to report it still doesn't work. downloaded it today, tried it on r2009b and r2010a. frustratingly sometimes it works sometimes it doenst.

1) run from a script - it works
2) run from opening function of a GUI created using guide - doesn't work
3) run the script from #1 after #2 failed - it doesn't work!
4) reopen matlab and run #1 - works

very strange.

[Yair Altman]

Patrick, Emad & Jayveer - I have yesterday uploaded a new version of FindJObj that fixes the problem you have reported.

FYI, the problem occurred due to a slightly different implementation of the Java hierarchy for Matlab figure windows. The new code should work find on all the older Matlab 7 versions *IN ADDITION* to R2010a.

As always, I am very committed to fixing such utilities, to the best of my abilities, also in upcoming Matlab releases.

[Jveer]

findjobj returns [] on r2010a !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

which makes the following tutorial useless!! - http://undocumentedmatlab.com/blog/rich-matlab-editbox-contents/#EditorKit along with everything else on the website since they all depend on finjobj!

[Kusa358 Figueredo]

 

[Emad Hasan]

I have the same problem as Patrick.

I made a slider using GUIDE; its handle is hSlider.
I called jSlider = findjobj(hSlider);
I tried this with MATLAB 2007b, this worked very well, thank you.

Then I tried this with MATLAB 2009a, findjobj returned empty!
Actually, calling findjobj with any arguments all returned empty.

What did I do wrong?

[Yair Altman]

Dear Malcolm - Thanks for the feedback.

ApplicationData is a hidden property which is not shown by the property inspector used by FindJObj.

To see this information, simply select the relevant object in the FindJObj hierarchy tree and click the "Inspect object" button. This opens the UIInspect utility, which does display ApplicationData (if available) in UIInspect's bottom-right ("other properties") table.

If you need more control, you can always use FindJObj's "Export to workspace" button, and get the ApplicationData from the exported object handle.

[Malcolm Lidierth]

Superb tool Yair. Do you any plans to provide access to the application data areas of the objects e.g. from the context menu in the left-hand panel?

[Alexander Kosenkov]

That's simply amazing how deep inside could you get into Matlab internals! That's incredibily useful if one needs to bult-in matlab into Java application. Something like this should be definetely included into Builder JA

[James]

thx

[Oliver Woodford]

Great function. The interactive display is a brilliant feature.

[Patrick Tai]

I made a slider using GUIDE; its handle is hSlider.
I called jSlider = findjobj(hSlider);
I tried this with MATLAB 2007b, this worked very well, thank you.

Then I tried this with MATLAB 2009a, findjobj returned empty!
Actually, calling findjobj with any arguments all returned empty.

What did I do wrong?

[Saidul Hasnan]

Why do I get this error whenever i tried findjobj;

??? findjobj: Undefined function or variable "jcb".

I have the latest version of findjobj file.

[Boris]

 

[Jesse Hopkins]

I've actually solved my problem. After reading this page: http://undocumentedmatlab.com/blog/uicontrol-callbacks/,
I tried changing the way I set the callbacks. Before, I set the callbacks directly on the java-object. However, when I used the handle() function and then set the callbacks the problem disappears.

In summary:
before:
set(myJavaObject,'MouseReleasedCallback',@callbackfcn);

now:
myHandle = handle(myJavaObject,'CallbackProperties');
set(myHandle,'MouseReleasedCallback,@callbackfcn)

[Jesse Hopkins]

I've been using this file for about a year now (great work Yair!), and a very weird issue has crept up now that I've upgraded from R2007b to R2008b.

What happens to me is that I have a few custom java-objects instantiated (they are a modified version of the java-swing table), with userdata and function callbacks associated with them via calls like: set(myTableObj,'MouseReleasedCallback',@callbackfcn);
set(myTableObj,'userdata',data);

After findjobj returns, all of the userdata and callbacks have been cleared out. I've stepped through findjobj line by line, and cannot find a culprit. In fact, when I get to the "return" line on 279, the userdata and function callbacks are still properly associated with the java-objects. However, once findjobj returns, all userdata and function callbacks of my java-objects are cleared to an empty matrix.

Any thoughts on this?

[Yair Altman]

@Leonardo - FindJObj does not enable modifying the displayed object hierarchy - perhaps I will add this feature in a future version. You need to update the hierarchy outside FindJObj and then click on the <Refresh Tree> button.

[Leonardo Glavina]

Great file! i just have one doubt using it: if I can chance the order of some structures. I have some check boxes and using 'tab' to select them is completely out of order, and using this function I found that it's following the specific order that is on the tree.

So, can I change the place of my tree's items?

thanks for the code

[Qun HAN]

Great work, Yair! I have refferenced it in my spaces.
Only one suggestion: To be compatible with future versions of ML, the use of "JavaFrame" in your function should be avoid. The "JavaFrame" is a com.mathworks.hg.peer.FigurePeer Object, it can be easily obtained using a JAVA approach instead of the get(hfig,'JavaFrame'). For example, you can get if from the mde's Client.

[Dennis Olly]

ucd puri,

> but i did not understand how did you figured out
> AdjustmentValueChangedCallback attribute in line below

I just used findjobj itself:

hSlider = uicontrol('style','slider' );
findjobj( hSlider )

Dennis

btw: did I mention findjobj is excellent !?

[Matthias Höller]

Awesome tool to find the underlying java objects of MATLAB objects! Works great!

[Husam Aldahiyat]

 

[Zhang Yanxiang]

Great work!

[Jveer]

brilliant!

[Jveer]

 

[Sebastian Hölz]

Another suggestion (valid for Matlab 7.5):

If you want to inspect the Editor-container, you will need to change lines 175-176 from

origContainer = container;
contentSize = [container.getWidth, container.getHeight];

to

origContainer = container;
if strcmp(container.getName,'Editor');
container=container.getInternalFrame;
end
contentSize = [container.getWidth, container.getHeight];

Sebastian

[Sebastian Hölz]

Info for MATLAB 7.5.
An inconsistency in uitreenode.m (%MATLAB%\toolbox\matlab\uitools\uitreenode.m) prevents "findjobj" to work properly. You have to change the first line in "uitreenode.m" from ...

function node = uitreenode(value, string, icon, isLeaf)

... to ...
function node = uitreenode(dummy,value, string, icon, isLeaf)

... , then everything initializes just fine.

After fixing that, it's SWEET! I've just spend hours and hours writing down the hirarchy of objects and was just starting to think, how nice it would be to have everything at hand in "file"-browser ... well, you know it: it's all on the FEX, ... somewhere ...

Thanks,

Sebastian

[ucd puri]

thanks

[Yair Altman]

ucd puri - jControl and uiComponent are simply Matlab functions that enable easy access and usage of Java controls, which in general are more powerful than the basic Matlab controls. The FindJObj function is useful for finding the handle of a Java control within a Matlab figure, similarly to Matlab's basic findobj function.

Java control functionality can be googled (e.g., "java jslider") , or you can read any good book or online tutorial about Java Swing (e.g., java.sun.com/docs/books/tutorial/uiswing/components/). Alternately, you can use my uiInspect submission on the Matlab File Exchange to see exactly which properties/methods/callbacks are available for any component (Java, Matlab or COM) - http://www.mathworks.com/matlabcentral/fileexchange/17935

Yair Altman

[ucd puri]

I implemented this function Dennis's way. it works perfect. Thanl all. but i did not understand how did you figured out AdjustmentValueChangedCallback attribute in line below

jSlider.AdjustmentValueChangedCallback = {@FollowSliceSliderCallback,guidata(gcbo)};

Which all other attributes i can use with jSlider.(.....)
and how to find ot about them.
Regards n Thanks for tips
Tanuj

[ucd puri]

HI All, One more stupid question if you dnt mind. I am an intermidiate user of matlab, and learning more. I did not exactly understood the difference between
1) jControl function
2) findjObj function, and
3) uiComponent function.
Regards n Thanks for help. Tanuj

[Yair Altman]

The R2008 warnings can be eliminated by typing:

warning('off','MATLAB:HandleGraphics:ObsoletedProperty:JavaFrame');
warning('off','MATLAB:uitreenode:MigratingFunction');

I'll add it to a new version soon, but you can simply use this in your startup file or your Matlab Command Window.
Yair

[Jesse Hopkins]

Running this in R2008a brings up the warning:
Warning: figure JavaFrame property will be obsoleted in a future release. For more information see the JavaFrame resource on
the MathWorks Web site.
> In findjobj>getRootPanel at 266
In findjobj at 164

[Johnny Smith]

I guess, ln 257 should be

set(0,'ShowHiddenHandles','on');

instead of

set(0,'ShowHiddenHandles','off');

thanks!

[Jack Zheng]

a great piece of work! thanks!

Yair, is that possible for you to make it compatible with 08a? it causes a bunch of thread error/warning in 08a.

thank you!

[Yair Altman]

Peter - all you need to do to prevent scanning the menu-bar is to add the '-nomenu' option. For example: jObj=findjobj(hObj,'-nomenu'); Unfortunately, I could not find a way to scan the menu-bar without actually activating all menu options.

[Peter Li]

Is it just me or does everyone who uses this script have problem on initialization.

Whenever start my own script which uses findjobj, "it" scrolls through the top menu ('file', 'edit','view','insert',...'help'). This is a little annoying

[Dennis Olly]

Thanks for the reply, Yair!

I am using: % $Revision: 1.9 $ $Date: 2007/08/14 23:03:04 $ which is the version I get when clicking the .m button on Mathworks (this page). Is there indeed I later version?

Nevertheless, you provided the solution saying the control has to be rendered. I created both the uicontrol AND the javacallback in the OpeningFcn.
I left the creation of the uicontrol in place but now I moved the below lines of code to the OutputFcn (not sure if that's a proper place for such purposes though):

jSlider = findjobj( handles.sliceSlider );
drawnow;
jSlider.AdjustmentValueChangedCallback = {@FollowSliceSliderCallback,guidata(gcbo)};

Now it works perfectly. Thanks again!
Dennis

[Yair Altman]

Thanks for your feedback Dennis.

Please ensure you're using the latest version of FindJObj (currently dating 2007-11-13). Also, when calling findjobj immediately after creating a UI control, you must let the Matlab/Java engine time to fully render the control. This can be done with a simple drawnow command, possibly followed by a small pause(0.01).

Yair

[Dennis Olly]

I found out that

jSlider = findjobj(hSlider)
ans = <1x0>

eventhough just doing

findjobj

lists all java-objects including the slider.
Also, when just using the Command Window, it works find: I can create figure with a slider with a callback that continuously calls an .m file.

Dennis

[Dennis Olly]

Using Matlab 7.5 (R2007b) and doing

1 hSlider = uicontrol('style','slider' );
2 jSlider = findjobj(hSlider);
3 jSlider.AdjustmentValueChangedCallback = @FollowSliceSlider_Callback;

I get:
No public field AdjustmentValueChangedCallback exists for class handle

Using:

set(jSlider,
'AdjustmentValueChangedCallback', @FollowSliceSlider_Callback );

I get no error, but the callback function is never reached.

Am I missing something here?
Thanks for any help
Dennis

[Yair Altman]

Bob - the bottom tree branch that FindJObj displays is the Handle Graphics hierarchy - only the top branch is the Java hierarchy. If you don't see it, perhaps you're not using the latest version of FindJObj.

[Bob W]

This is interesting, would it be easy to organize the objects the way as they are thought of in the Child/Parent as the handle graphics user would see them?

[Yair Altman]

the cellfun behavior has changed in Matlab 7.1 - unfortunately FINDJOBJ relies on the new behavior, so you must have version 7.1+ to run. Sorry about the confusion...

[YP P]

Hello Yair!
Sorry for typing mistake in the post. The matlab command issued is "findjobj" and not "finjobj". I have not renamed the file. The file name is kept "findjobj.m" only. I ensure that script is run by setting breakpoints in the m-file.
So here I restate the problem.
If I issue the command, the figure window is created and I get following error message

>> findjobj
findjobj
??? findjobj: Function name must be a string.

If I set breakpoint for error,the error is reported at line 234 of the code. The value of error variable is

K>> err

err =

message: 'findjobj: Function name must be a string.'
identifier:'MATLAB:cellfun:InvalidFirstInput'

The Java version is

Java 1.5.0 with Sun Microsystems Inc. Java HotSpot(TM) Client VM (mixed mode)

with regards,
YP
--

[YP P]

On MATLAB Version 7.0.4.365 (R14) Service Pack 2 I get following error when findjobj is run (with and without arguments)

>>finjobj
??? findjobj: Function name must be a string.

[Mikhail Poda Razumtsev]

It is the best piece of code on Matlab/Java I have ever seen in Matlab Central. I am very grateful to the author for sharing his knowledge.