filename = uigetfile_with_preview(filterSpec, prompt, folder, callbackFunction, multiSelectFlag)

1. I used a com.mathworks.hg.util.dFileChooser component for the main file selector. This is a builtin Matlab control that extends the standard javax.swing.JFileChooser with a few properties and methods. I don’t really need the extra features, so you can safely replace the component with a JFileChooser if you wish (lines 54-55). Various properties of the file selector are then set, such as the folder that is initially displayed, the multi-selection flag, the component background color, and the data-type filter options.
2. I used the javacomponent function to place the file-selector component within the dialog window.
3. I set a callback on the component’s PropertyChangeCallback that is invoked whenever the user interactively selects a new file. This callback clears the preview panel and then calls the user-defined callback function (if available).
4. I set a callback on the component’s ActionPerformedCallback that is invoked whenever the user closes the figure or clicks the “Open” button. The selected filename(s) is/are then returned to the caller and the dialog window is closed.
5. I set a callback on the component’s file-name editbox’s KeyTypedCallback that is invoked whenever the user types in the file-name editbox. The callback checks whether the entered text looks like a valid folder path and if so then it automatically updates the displayed folder as-you-type.

If you want to convert the code to a uiputfile variant, add the following code lines before the uiwait in line 111:

hjFileChooser.setShowOverwriteDialog(true);  % default: false (true will display a popup alert if you select an existing file)
hjFileChooser.setDialogType(hjFileChooser.java.SAVE_DIALOG);  % default: OPEN_DIALOG
hjFileChooser.setApproveButtonText('Save');  % or any other string. Default for SAVE_DIALOG: 'Save'
hjFileChooser.setApproveButtonToolTipText('Save file');  % or any other string. Default for SAVE_DIALOG: 'Save selected file'

In memory of my dear father.

The post uigetfile/uiputfile customizations appeared first on Undocumented Matlab.

// Most important functions (C):
bool utIsInterruptEnabled(void)
bool utIsInterruptPending(void)
bool utWasInterruptHandled(void)
bool utSetInterruptHandled(bool)
bool utSetInterruptEnabled(bool)
bool utSetInterruptPending(bool)
// Related functions (C, signature unknown):
? utHandlePendingInterrupt(?)
? utRestoreInterruptEnabled(?)
? utLongjmpIfInterruptPending(?)
// utInterruptMode class (C++):
utInterruptMode::utInterruptMode(enum utInterruptMode::Mode)  // constructor
utInterruptMode::~utInterruptMode(void)  // destructor
bool utInterruptMode::isInterruptEnabled(void)
enum utInterruptMode::Mode utInterruptMode::CurrentMode
enum utInterruptMode::Mode utInterruptMode::GetCurrentMode(void)
enum utInterruptMode::Mode utInterruptMode::GetOriginalMode(void)
enum utInterruptMode::Mode utInterruptMode::SetMode(enum utInterruptMode::Mode)
// utInterruptState class (C++):
class utInterruptState::AtomicPendingFlags utInterruptState::flags_pending
void utInterruptState::HandlePeekMsgPending(void)
bool utInterruptState::HandlePendingInterrupt(void)
bool utInterruptState::interrupt_handled
bool utInterruptState::IsInterruptPending(void)
bool utInterruptState::IsPauseMsgPending(void)
class utInterruptState & utInterruptState::operator=(class utInterruptState const &)
void utInterruptState::PeekMessageIfPending(void)
bool utInterruptState::SetInterruptHandled(bool)
bool utInterruptState::SetInterruptPending(bool)
bool utInterruptState::SetIqmInterruptPending(bool)
bool utInterruptState::SetPauseMsgPending(bool)
bool utInterruptState::SetPeekMsgPending(bool)
void utInterruptState::ThrowIfInterruptPending(void)
bool utInterruptState::WasInterruptHandled(void)
unsigned int const utInterruptState::FLAG_PENDING_CTRLC
unsigned int const utInterruptState::FLAG_PENDING_INTERRUPT_MASK
unsigned int const utInterruptState::FLAG_PENDING_IQM_INTERRUPT
unsigned int const utInterruptState::FLAG_PENDING_PAUSE
unsigned int const utInterruptState::FLAG_PENDING_PEEKMSG

Of all these functions, we can make do with just utIsInterruptPending, as shown by Yin (complete with compilation instructions):

/* A demo of Ctrl-C detection in mex-file by Wotao Yin. Jan 29, 2010. */
#include "mex.h"
#if defined (_WIN32)
    #include 
#elif defined (__linux__)
    #include 
#endif
#ifdef __cplusplus
    extern "C" bool utIsInterruptPending();
#else
    extern bool utIsInterruptPending();
#endif
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
    int count = 0;
    while(1) {
        #if defined(_WIN32)
            Sleep(1000);        /* Sleep one second */
        #elif defined(__linux__)
            usleep(1000*1000);  /* Sleep one second */
        #endif
        mexPrintf("Count = %d\n", count++);  /* print count and increase it by 1 */
        mexEvalString("drawnow;");           /* flush screen output */
        if (utIsInterruptPending()) {        /* check for a Ctrl-C event */
            mexPrintf("Ctrl-C Detected. END\n\n");
            return;
        }
        if (count == 10) {
            mexPrintf("Count Reached 10. END\n\n");
            return;
        }
    }
}

After returning to Matlab, the Ctrl-C event will stop the execution of the caller function(s). However, sometimes we would like to keep the partial calculation, for example if the calculation can later be resumed from the point of interruption. It’s not possible to save partial result using only the utIsInterruptPending() function. However, it is possible to reset the interrupt state so that Matlab will not stop the execution after returning control from the mex function, and the caller function can get and use the partial calculation. The magic is done using another undocumented libut function named ​utSetInterruptPending(). A short example is included below (provided by Zvi Devir):

// Import libut functions
#pragma comment(lib, "libut.lib")
extern "C" bool utIsInterruptPending();
extern "C" bool utSetInterruptPending(bool);
// Run calculation divided into steps
int n;
for (n = 0; n < count; n++) {
	// some expensive calculation
	a_long_calculation(..., n);
	if (utIsInterruptPending()) {		// check for a Ctrl-C event
		mexPrintf("Ctrl-C detected [%d/%d].\n\n", n, count);
		utSetInterruptPending(false);	// Got it... consume event
		break;
	}
}
// Write back partial or full calculation
...

An elaboration of the idea of Ctrl-C detection was created by Ramon Casero (Oxford) for the Gerardus project. Ramon wrapped Yin's code in C/C++ #define to create an easy-to-use pre-processor function ctrlcCheckPoint(fileName,lineNumber):

...
ctrlcCheckPoint(__FILE__, __LINE__);  // exit if user pressed Ctrl+C
...

Here's the code for the preprocessor header file (GerardusCommon.h) that #defines ctrlcCheckPoint() (naturally, the __FILE__ and __LINE__ parts could also be made part of the #define, for even simpler usage):

 /*
  * Author: Ramon Casero 
  * Copyright © 2011-2013 University of Oxford
  * Version: 0.10.2
  *
  * University of Oxford means the Chancellor, Masters and Scholars of
  * the University of Oxford, having an administrative office at
  * Wellington Square, Oxford OX1 2JD, UK.
  *
  * This file is part of Gerardus.
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details. The offer of this
  * program under the terms of the License is subject to the License
  * being interpreted in accordance with English Law and subject to any
  * action against the University of Oxford being under the jurisdiction
  * of the English Courts.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see
  * .
  */
#ifndef GERARDUSCOMMON_H
#define GERARDUSCOMMON_H
/* mex headers */
#include 
/* C++ headers */
#include 
#include 
#include 
#include 
#include 
/* ITK headers */
#include "itkOffset.h"
/*
 * utIsInterruptPending(): "undocumented MATLAB API implemented in
 * libut.so, libut.dll, and included in the import library
 * libut.lib. To use utIsInterruptPending in a mex-file, one must
 * manually declare bool utIsInterruptPending() because this function
 * is not included in any header files shipped with MATLAB. Since
 * libut.lib, by default, is not linked by mex, one must explicitly
 * tell mex to use libut.lib." -- Wotao Yin,
 * http://www.caam.rice.edu/~wy1/links/mex_ctrl_c_trick/
 *
 */
#ifdef __cplusplus
    extern "C" bool utIsInterruptPending();
#else
    extern bool utIsInterruptPending();
#endif
/*
 * ctrlcCheckPoint(): function to check whether the user has pressed
 * Ctrl+C, and if so, terminate execution returning an error message
 * with a hyperlink to the offending function's help, and a hyperlink
 * to the line in the source code file this function was called from
 *
 * It is implemented as a C++ macro to check for the CTRL+C flag, and
 * a call to function ctrlcErrMsgTxt() inside, to throw the error. The
 * reason is that if ctrlcCheckPoint() were a function instead of a
 * macro, this would introduce a function call at every iteration of
 * the loop, which is very expensive. But then we don't want to put
 * the whole error message part inside a macro, it's bug-prone and bad
 * programming practice. And once the CTRL+C has been detected,
 * whether the error message is generated a bit faster or not is not
 * important.
 *
 * In practice, to use this function put a call like this e.g. inside
 * loops that may take for a very long time:
 *
 *    // exit if user pressed Ctrl+C
 *    ctrlcCheckPoint(__FILE__, __LINE__);
 *
 * sourceFile: full path and name of the C++ file that calls this
 *             function. This should usually be the preprocessor
 *             directive __FILE__
 *
 * lineNumber: line number where this function is called from. This
 *             should usually be the preprocessor directive __LINE__
 *
 */
inline
void ctrlcErrMsgTxt(std::string sourceFile, int lineNumber) {
  // run from here the following code in the Matlab side:
  //
  // >> path = mfilename('fullpath')
  //
  // this provides the full path and function name of the function
  // that called ctrlcCheckPoint()
  int nlhs = 1; // number of output arguments we expect
  mxArray *plhs[1]; // to store the output argument
  int nrhs = 1; // number of input arguments we are going to pass
  mxArray *prhs[1]; // to store the input argument we are going to pass
  prhs[0] = mxCreateString("fullpath"); // input argument to pass
  if (mexCallMATLAB(nlhs, plhs, nrhs, prhs, "mfilename")) { // run mfilename('fullpath')
    mexErrMsgTxt("ctrlcCheckPoint(): mfilename('fullpath') returned error");
  }
  if (plhs == NULL) {
    mexErrMsgTxt("ctrlcCheckPoint(): mfilename('fullpath') returned NULL array of outputs");
  }
  if (plhs[0] == NULL) {
    mexErrMsgTxt("ctrlcCheckPoint(): mfilename('fullpath') returned NULL output instead of valid path");
  }
  // get full path to current function, including function's name
  // (without the file extension)
  char *pathAndName = mxArrayToString(plhs[0]);
  if (pathAndName == NULL) {
    mexErrMsgTxt("ctrlcCheckPoint(): mfilename('fullpath') output cannot be converted to string");
  }
  // for some reason, using mexErrMsgTxt() to give this output
  // doesn't work. Instead, we have to give the output to the
  // standar error, and then call mexErrMsgTxt() to terminate
  // execution of the program
  std::cerr << "Operation terminated by user during "
	    << ""
	    << mexFunctionName()
	    << " (line " << lineNumber
	    << ")"
	    << std::endl;
  mexErrMsgTxt("");
}
#define ctrlcCheckPoint(sourceFile, lineNumber)		\
  if (utIsInterruptPending()) {				\
    ctrlcErrMsgTxt(sourceFile, lineNumber);		\
  }

This feature has remained as-is since at least 2002 (when Peter first reported it), and apparently works to this day. Why then did I categorize this as "High risk for breaking in a future Matlab versions"? The reason is that internal undocumented MEX functions are prone to break in new Matlab releases (example). Hopefully my report today will prompt MathWorks to make this feature documented, rather than to remove it from a future release 🙂
By the way, if anyone knows any use for the other interrupt-related functions in libut that I listed above, and/or the missing signatures, please leave a note below and I will update here accordingly.
Addendum July 2, 2016: Pavel Holoborodko just posted an asynchronous version of this mechanism, which is an improvement of the synchronous code above. Pavel uses a separate Windows thread to check the Ctrl-C interrupt state. Readers can extend this idea to use threads for other asynchronous (multi-threaded) computations or I/O. In chapter 7 of my book "Accelerating MATLAB Performance" I explain how we can use Posix threads (pthreads) or OpenMP threads for similar multithreading in MEX (unlike Windows threads, pthreads and OpenMP are cross platform). Users can also use other multithreading solutions, such as the open-source Boost library (bundled with Matlab) or Intel's commercial TBB.

The post MEX ctrl-c interrupt appeared first on Undocumented Matlab.

Technical components

The pieces of today’s post were already discussed separately on this website, but never shown together as I will do today:

• The search box component (com.mathworks.widgets.SearchTextField) was discussed in last year’s article on auto-completion widgets
• I showed how to add custom controls to the figure toolbar in a 2009 post (time flies!)
• I discussed controlling toolbar components’ size in another old post
• I discussed my findjobj utility, used for accessing the underlying Java components of Matlab uicontrols in another article
• I discussed Matlab’s use of EDT in a dedicated article on the subject back in 2010 (and I’ll have more to say about this subject next week)
• Finally, I discussed how to trap Java control events in Matlab in separate articles here and here

Adding a search-box to the figure toolbar

As a first step, let’s create the search-box component and add it to our figure’s toolbar:

% First, create the search-box component on the EDT, complete with invokable Matlab callbacks:
jSearch = com.mathworks.widgets.SearchTextField('Symbol');  % 'Symbol' is my default search prompt
jSearchPanel = javaObjectEDT(jSearch.getComponent);  % this is a com.mathworks.mwswing.MJPanel object
jSearchPanel = handle(jSearchPanel, 'CallbackProperties');  % enable Matlab callbacks
% Now, set a fixed size for this component so that it does not resize when the figure resizes:
jSize = java.awt.Dimension(100,25);  % 100px wide, 25px tall
jSearchPanel.setMaximumSize(jSize)
jSearchPanel.setMinimumSize(jSize)
jSearchPanel.setPreferredSize(jSize)
jSearchPanel.setSize(jSize)
% Now, attach the Matlab callback function to search box events (key-clicks, Enter, and icon clicks):
jSearchBox = handle(javaObjectEDT(jSearchPanel.getComponent(0)), 'CallbackProperties');
set(jSearchBox, 'ActionPerformedCallback', {@searchSymbol,hFig,jSearchBox})
set(jSearchBox, 'KeyPressedCallback',      {@searchSymbol,hFig,jSearchBox})
jClearButton = handle(javaObjectEDT(jSearchPanel.getComponent(1)), 'CallbackProperties');
set(jClearButton, 'ActionPerformedCallback', {@searchSymbol,hFig,jSearchBox})
% Now, get the handle for the figure's toolbar:
hToolbar = findall(hFig,'tag','FigureToolBar');
jToolbar = get(get(hToolbar,'JavaContainer'),'ComponentPeer');  % or: hToolbar.JavaContainer.getComponentPeer
% Now, justify the search-box to the right of the toolbar using an invisible filler control
% (first add the filler control to the toolbar, then the search-box control):
jFiller = javax.swing.Box.createHorizontalGlue;  % this is a javax.swing.Box$Filler object
jToolbar.add(jFiller,      jToolbar.getComponentCount);
jToolbar.add(jSearchPanel, jToolbar.getComponentCount);
% Finally, refresh the toolbar so that the new control is displayed:
jToolbar.revalidate
jToolbar.repaint

Search action callback functionality

Now that the control is displayed in the toolbar, let’s define what our Matlab callback function searchSymbol() does. Remember that this callback function is invoked whenever any of the possible events occur: keypress, <Enter>, or clicking the search-box’s icon (typically the “x” icon, to clear the search term).
We first reset the search-box appearance (foreground/background colors), then we check the search term (if non-empty). Based on the selected tab, we search the corresponding data table’s symbol column(s) for the search term. If no match is found, we highlight the search term by setting the search-box’s text to be red over yellow. Otherwise, we change the table’s selected row to the next match’s row index (i.e., the row following the table’s currently-selected row, cycling back at the top of the table if no match is found lower in the table).
Reading and updating the table’s selected row requires using my findjobj utility – for performance considerations the jTable handle should be cached (perhaps in the hTable’s UserData or ApplicationData):

% Callback function to search for a symbol
function searchSymbol(hObject, eventData, hFig, jSearchBox)
    try
        % Clear search-box formatting
        jSearchBox.setBackground(java.awt.Color.white)
        jSearchBox.setForeground(java.awt.Color.black)
        jSearchBox.setSelectedTextColor(java.awt.Color.black)
        jSearchBox.repaint
        % Search for the specified symbol in the data table
        symbol = char(jSearchBox.getText);
        if ~isempty(symbol)
            handles = guidata(hFig);
            hTab = handles.hTabGroup.SelectedTab;
            colOffset = 0;
            forceCol0 = false;
            switch hTab.Title
                case 'Scanning'
                    hTable = handles.tbScanResults;
                    symbols = cell(hTable.Data(:,1));
                case 'Correlation'
                    hTable = handles.tbCorrResults;
                    symbols = cell(hTable.Data(:,1:2));
                case 'Backtesting'
                    hTab = handles.hBacktestTabGroup.SelectedTab;
                    hTable = findobj(hTab, 'Type','uitable', 'Tag','results');
                    pairs = cell(hTable.Data(:,1));
                    symbols = cellfun(@(c)strsplit(c,'/'), pairs, 'uniform',false);
                    symbols = reshape([symbols{:}],2,[])';
                    forceCol0 = true;
                case 'Trading'
                    hTable = handles.tbTrading;
                    symbols = cell(hTable.Data(:,2:3));
                    colOffset = 1;
                otherwise  % ignore
                    return
            end
            if isempty(symbols)
                return
            end
            [rows,cols] = ind2sub(size(symbols), find(strcmpi(symbol,symbols)));
            if isempty(rows)
                % Not found - highlight the search term
                jSearchBox.setBackground(java.awt.Color.yellow)
                jSearchBox.setForeground(java.awt.Color.red)
                jSearchBox.setSelectedTextColor(java.awt.Color.red)
                jSearchBox.repaint
            elseif isa(eventData, 'java.awt.event.KeyEvent') && isequal(eventData.getKeyCode,10)
                % Found with  event - highlight the relevant data row
                jTable = findjobj(hTable);
                try jTable = jTable.getViewport.getView; catch, end  % in case findjobj returns the containing scrollpane rather than the jTable
                [rows, sortedIdx] = sort(rows);
                cols = cols(sortedIdx);
                currentRow = jTable.getSelectedRow + 1;
                idx = find(rows>currentRow,1);
                if isempty(idx),  idx = 1;  end
                if forceCol0
                    jTable.changeSelection(rows(idx)-1, 0, false, false)
                else
                    jTable.changeSelection(rows(idx)-1, cols(idx)-1+colOffset, false, false)
                end
                jTable.repaint
                jTable.getTableHeader.repaint
                jTable.getParent.getParent.repaint
                drawnow
            end
        end
    catch
        % never mind - ignore
    end
end

That’s all there is to it. In my specific case, changing the table’s selected row cased an immediate trigger that updated the associated charts, synchronized the other data tables and did several other background tasks.

What about the new web-based uifigure?

The discussion above refers only to traditional Matlab figures (both HG1 and HG2), not to the new web-based (AppDesigner) uifigures that were officially introduced in R2016a (I wrote about it last year).
AppDesigner uifigures are basically webpages rather than desktop windows (JFrames). They use an entirely different UI mechanism, based on HTML webpages served from a localhost webserver, using the DOJO Javascript toolkit for visualization and interaction, rather than Java Swing as in the existing JFrame figures. The existing figures still work without change, and are expected to continue working alongside the new uifigures for the foreseeable future. I’ll discuss the new uifigures in separate future posts (in the meantime you can read a bit about them in my post from last year).
I suspect that the new uifigures will replace the old figures at some point in the future, to enable a fully web-based (online) Matlab. Will this happen in 2017 or 2027 ? – your guess is as good as mine, but my personal guesstimate is around 2018-2020.

The post Adding a search box to figure toolbar appeared first on Undocumented Matlab.

Displaying the Shortcuts panel

Before we begin to modify shortcuts in the Toolstrip’s shortcuts menu, we need to ensure that the Shortcuts panel is visible and active (in current focus), otherwise our customizations will be ignored or cause an error. There is probably a more direct way of doing this, but a simple way that I found was to edit the current Desktop’s layout to include a directive to display the Shortcuts tab, and then load that layout:

jDesktop = com.mathworks.mde.desk.MLDesktop.getInstance;
hMainFrame = com.mathworks.mde.desk.MLDesktop.getInstance.getMainFrame;
jToolstrip = hMainFrame.getToolstrip;
isOk = jToolstrip.setCurrentTab('shortcuts');
if ~isOk  % i.e., Shortcuts tab is NOT displayed
    % Save the current Desktop layout
    jDesktop.saveLayout('Yair');  pause(0.15);
    % Update the layout file to display the Shortcuts tab
    filename = fullfile(prefdir, 'YairMATLABLayout.xml');
    fid = fopen(filename, 'rt');
    txt = fread(fid, '*char')';
    fclose(fid);
    txt = regexprep(txt,'(ShowShortcutsTab=)"[^"]*"','');
    txt = regexprep(txt,'(]*)>','$1 ShowShortcutsTab="yes">');
    fid = fopen(filename, 'wt');
    fwrite(fid,txt);
    fclose(fid);
    % Load the modified layout
    jDesktop.restoreLayout('Yair');  pause(0.15);
    % The shortcuts tab should now be visible, so transfer focus to that tab
    jToolstrip.setCurrentTab('shortcuts');
end

Custom controls

As I explained in last week’s post, we can use scUtils.addShortcutToBottom to add a simple push-button shortcut to the relevant category panel within the Shortcuts toolstrip tab. To add custom controls, we can simply add the controls to the relevant shortcut category panel container (a com.mathworks.toolstrip.components.TSPanel object). The standard shortcuts are typically placed in the Shortcuts tab’s second TSPanel (“general”), and other categories have TSPanels of their own.
Now here’s the tricky part about TSPanels: we cannot directly add components to the sectino panel (that would be too easy…): the section panels are composed of an array of internal TSPanels, and we need to add the new controls to those internal panels. However, these panels only contain 3 empty slots. If we try to add more than 3 components, the 4th+ component(s) will simply not be displayed. In such cases, we need to create a new TSPanel to display the extra components.
Here then is some sample code to add a combo-box (drop-down) control:

% First, get the last internal TSPanel within the Shortcuts tab's "general" section panel
% Note: jToolstrip was defined in the previous section above
jShortcutsTab = jToolstrip.getModel.get('shortcuts').getComponent;
jSectionPanel = jShortcutsTab.getSectionComponent(1).getSection.getComponent;  % the TSPanel object "general"
jContainer = jSectionPanel.getComponent(jSectionPanel.getComponentCount-1);
% If the last internal TSPanel is full, then prepare a new internal TSPanel next to it
if jContainer.getComponentCount >= 3
    % Create a new empty TSPanel and add it to the right of the last internal TSPanel
    jContainer = com.mathworks.toolstrip.components.TSPanel;
    jContainer.setPreferredSize(java.awt.Dimension(100,72));
    jSectionPanel.add(jContainer);
    jSectionPanel.repaint();
    jSectionPanel.revalidate();
end
% Create the new control with a custom tooltip and callback function
optionStrings = {'Project A', 'Project B', 'Project C'};
jCombo = com.mathworks.toolstrip.components.TSComboBox(optionStrings);
jCombo = handle(javaObjectEDT(jCombo), 'callbackproperties'));
set(jCombo, 'ActionPerformedCallback', @myCallbackFunction);
jCombo.setToolTipText('Select the requested project');
% Now add the new control to the internal TSPanel
jContainer.add(jCombo);
jContainer.repaint();
jContainer.revalidate();

dataModel = javax.swing.SpinnerNumberModel(125, 15, 225, 0.5);  % defaultValue, minValue, maxValue, stepSize
jSpinner = com.mathworks.toolstrip.components.TSSpinner(dataModel);
jSpinner = handle(javaObjectEDT(jSpinner), 'CallbackProperties');
[hjSpinner, hContainer] = javacomponent(jSpinner, [10,10,60,20], gcf);

You can find additional interesting components within the %matlabroot%/java/jar/toolstrip.jar file, which can be opened in any zip file utility or Java IDE. In fact, whatever controls that you see Matlab uses in its Desktop toolstrip (including galleries etc.) can be replicated in custom tabs, sections and panels of our own design.
Matlab Desktop’s interactive GUI only enables creating simple push-button shortcuts having string callbacks (that are eval‘ed in run-time). Using the undocumented programmatic interface that I just showed, we can include more sophisticated controls, as well as customize those controls in ways that are impossible via the programmatic GUI: add tooltips, set non-string (function-handle) callbacks, enable/disable controls, modify icons in run-time etc.
For example (intentionally showing two separate ways of setting the component properties):

% Toggle-button
jTB = handle(javaObjectEDT(com.mathworks.toolstrip.components.TSToggleButton('Toggle button')), 'CallbackProperties')
jTB.setSelected(true)
jTB.setToolTipText('toggle me!')
jTB.ActionPerformedCallback = @(h,e)doSomething();
jContainer.add(jTB);
% Check-box
jCB = handle(javaObjectEDT(com.mathworks.toolstrip.components.TSCheckBox('selected !')), 'CallbackProperties');
set(jCB, 'Selected', true, 'ToolTipText','Please select me!', 'ActionPerformedCallback',{@myCallbackFunction,extraData});
jContainer.add(jCB);

(resulting in the screenshot at the top of this post)
Important note: none of these customizations is saved to file. Therefore, they need to be redone programmatically for each separate Matlab session. You can easily do that by calling the relevant code in your startup.m file.
If you wish me to assist with any customization of the Desktop shortcuts, or any other Matlab aspect, then contact me for a short consultancy.
Happy New Year everybody!

The post Programmatic shortcuts manipulation – part 2 appeared first on Undocumented Matlab.

The shortcuts.xml file

It turns out that the shortcults toolbar (on R2012a and earlier) or toolstrip group (on R2012b onward) is a reflection of the contents of the [prefdir ‘\shortcuts.xml’] file (depending on your version, the file might be named somewhat differently, i.e. shortcuts_2.xml). This file can be edited in any text editor, Matlab’s editor included. So a very easy way to programmatically affect the shortcuts is to update this file. Here is a sample of this file:

   
   
      Help Browser Favorites
      
         Help Using the Desktop
         Help icon
         helpview([docroot '/mapfiles/matlab_env.map'], 'matlabenvironment_desktop');
         true
      
   
   
      CSSM
      Help icon
      disp('No callback specified for this shortcut')
      true
   
   
      UndocML
      MATLAB icon
      web('undocumentedMatlab.com')
      true
   
   
      My favorite program
      C:\Yair\program\icon.gif
      cd('C:\Yair\program'); myProgram(123);
      true
   
   ...

The file is only loaded once during Matlab startup, so any changes made to it will only take effect after Matlab restarts.

Updating the shortcuts in the current Matlab session

We can update the shortcuts directly, in the current Matlab session, using the builtin com.mathworks.mlwidgets.shortcuts.­ShortcutUtils class. This class has existed largely unchanged for numerous releases (at least as far back as R2008b).
For example, to add a new shortcut to the toolbar:

name = 'My New Shortcut';
cbstr = 'disp(''My New Shortcut'')';  % will be eval'ed when clicked
iconfile = 'c:\path\to\icon.gif';  % default icon if it is not found
isEditable = 'true';
scUtils = com.mathworks.mlwidgets.shortcuts.ShortcutUtils;
category = scUtils.getDefaultToolbarCategoryName;
scUtils.addShortcutToBottom(name,cbstr,iconfile,category,isEditable);

The shortcut’s icon can either be set to a specific icon filepath (e.g., ‘C:\Yair\program\icon.jpg’), or to one of the predefined names: ‘Help icon’, ‘Standard icon’, ‘MATLAB icon’ or ‘Simulink icon’. The editable parameter does not seem to have a visible effect that I could see.
The category name can either be set to the default name using scUtils.getDefaultToolbarCategoryName (‘Shortcuts’ on English-based Matlab R2012b onward), or it can be set to any other name (e.g., ‘My programs’). To add a shortcut to the Help Browser (also known as a “Favorite”), simply set the category to scUtils.getDefaultHelpCategoryName (=’Help Browser Favorites’ on English-based Matlab installations); to add the shortcut to the ‘Start’ button, set the category to ‘Shortcuts’. When you use a non-default category name on R2012a and earlier, you will only see the shortcuts via Matlab’s “Start” button (as seen in the screenshot below); on R2012b onward you will see it as a new category group within the Shortcuts toolstrip (as seen in the screenshot above). For example:

scUtils = com.mathworks.mlwidgets.shortcuts.ShortcutUtils;
scUtils.addShortcutToBottom('clear', 'clear; clc', 'Standard icon', 'Special commands', 'true');

scUtils.removeShortcut('Shortcuts', 'My New Shortcut');

The addShortcutToBottom() method does not override existing shortcuts. Therefore, to ensure that we don’t add duplicate shortcuts, we must first remove the possibly-existing shortcut using removeShortcut() before adding it. Since removeShortcut() does not complain if the specific shortcut is not found, we can safely use it without having to loop over all the existing shortcuts. Alternately, we could loop over all existing category shortcuts checking their label, and adding a new shortcut only if it is not already found, as follows:

scUtils = com.mathworks.mlwidgets.shortcuts.ShortcutUtils;
category = scUtils.getDefaultToolbarCategoryName;
scVector = scUtils.getShortcutsByCategory(category);
scArray = scVector.toArray;  % Java array
foundFlag = 0;
for scIdx = 1:length(scArray)
   scName = char(scArray(scIdx));
   if strcmp(scName, 'My New Shortcut')
      foundFlag = 1; break;
      % alternatively: scUtils.removeShortcut(category, scName);
   end
end
if ~foundFlag
   scUtils.addShortcutToBottom(scName, callbackString, iconString, category, 'true');
end

As noted above, we can add categories by simply specifying a new category name in the call to scUtils.addShortcutToBottom(). We can also add and remove categories directly, as follows (beware: when removing a category, it is removed together with all its contents):

scUtils.addNewCategory('category name');
scUtils.removeShortcut('category name', []);  % entire category will be deleted

Shortcut tools on the Matlab File Exchange

Following my advice on StackOverflow back in 2010, Richie Cotton wrapped the code snippets above in a user-friendly utility (set of independent Matlab functions) that can now be found on the Matlab File Exchange and on his blog. Richie tested his toolbox on Matlab releases as old as R2008b, but the functionality may also work on even older releases.

Shortcuts panel embedded in Matlab GUI

Shortcuts are normally visible in the toolbar and the Matlab start menu (R2012a and earlier) or the Matlab Desktop’s toolstrip (R2012b onward). However, using com.mathworks.mlwidgets.shortcuts.ShortcutTreePanel, the schortcuts can also be displayed in any user GUI, complete with right-click context-menu:

jShortcuts = com.mathworks.mlwidgets.shortcuts.ShortcutTreePanel;
[jhShortcuts,hPanel] = javacomponent(jShortcuts, [10,10,300,200], gcf);

Stay tuned…

Next week I will expand the discussion of Matlab shortcuts with the following improvements:

1. Displaying non-standard controls as shortcuts: checkboxes, drop-downs (combo-boxes) and toggle-buttons
2. Customizing the shortcut tooltip (replacing the default tooltip that simply repeats the callback string)
3. Customizing the shortcut callback (rather than using an eval-ed callback string)
4. Enabling/disabling shortcuts in run-time

Merry Christmas everyone!

The post Programmatic shortcuts manipulation – part 1 appeared first on Undocumented Matlab.

uisetfont

The only documented font-selection alternative in Matlab is uisetfont, which presents a popup dialog window that returns the selected font properties in a simple Matlab struct:

>> font = uisetfont
font =
      FontName: 'Arial'
    FontWeight: 'normal'
     FontAngle: 'normal'
     FontUnits: 'points'
      FontSize: 10

DesktopFontPicker

DesktopFontPicker is a Swing component that presents a font selection panel that can easily be inserted into any Matlab GUI container (figure, panel or tab) using the javacomponent function:

font = java.awt.Font('Tahoma',java.awt.Font.PLAIN, 11);
jFontPanel = com.mathworks.widgets.DesktopFontPicker(true, font);
[jhPanel,hContainer] = javacomponent(jFontPanel, [10,10,250,170], gcf);

jFontPanel.setUseDesktopFontLabel('Use Yair''s standard font...')

jFont = jFontPanel.getSelectedFont();  % returns a java.awt.Font object
flag = jFontPanel.getUseDesktopFont();  % true if top radio-button is selected; false if custom font is selected

FontPrefsPanel

The builtin com.mathworks.mlwidgets.prefs.FontPrefsPanel class is used in Matlab to display the font preferences panel in the Preferences window. We can integrate it directly in our GUI:

jFontPanel=com.mathworks.mlwidgets.prefs.FontPrefsPanel(java.awt.Dimension);
[jhPanel,hContainer] = javacomponent(jFontPanel, [1,1,500,470], gcf);

Using this class is admittedly more cumbersome than DesktopFontPicker and I would not recommend using it in practice.

FontPicker

Font selection can also be shown with drop-downs (combo-boxes), rather than with lists as in DesktopFontPicker, FontPrefsPanel, or uisetfont. Use of drop-downs significantly reduces the display “real-estate” required by the control. This is useful in forms where the font selection is only one of several user-configurable options, and where enough space must be reserved for other configuration controls. We can do this using the com.mathworks.widgets.fonts.FontPicker class.
Up until Matlab release R2010a, FontPicker‘s constructor accepted optional parameters of a pre-selected font (a java.awt.Font object), an optional boolean flag indicating whether to display sample text using the selected font, an optional layout indicator, and optional list of selectable font names. Several screenshots of different parameter combinations are shown below:

import com.mathworks.widgets.fonts.FontPicker
jFontPicker = FontPicker(font, sampleFlag, layout);
[hjFontPicker, hContainer] = javacomponent(jFontPicker, position, gcf);

font=	[]	java.awt.Font('Tahoma', java.awt.Font.PLAIN, 8 )	[]
sampleFlag=	false	false	true
layout=	FontPicker.GRID_LAYOUT (=1)	FontPicker.LONG_LAYOUT (=2)	FontPicker.LONG_LAYOUT (=2)
position=	[10,200,140,40]	[10,200,225,20]	[10,200,225,80]

As before, the selected font can be retrieved using jFontPicker.getSelectedFont().
In Matlab release R2010b, FontPicker‘s interface changed, and the above code no longer works. This highlights a common pitfall in future-compatibility of internal components: even when the components remain, their interface sometimes changes. Here is the new code format, starting with R2010b:

jLayout = javaMethod('valueOf', 'com.mathworks.widgets.fonts.FontPicker$Layout', 'WIDE_WITH_SAMPLE');  % options: COMPACT, WIDE, WIDE_WITH_SAMPLE
jFont = java.awt.Font('Tahoma', java.awt.Font.PLAIN, 10);  % initial font to display (may not be [])
jFontPicker = com.mathworks.widgets.fonts.FontPicker(jFont, jLayout);
jFontPanel = jFontPicker.getComponent;
[jhPanel,hContainer] = javacomponent(jFontPanel, [10,10,250,120], gcf);

FontChooserPanel

As a final alternative for font selection, we can use the JIDE font-selection component. This component has two variants: as a drop-down/combo-box (com.jidesoft.combobox.FontComboBox) and as a standard JPanel (com.jidesoft.combobox.FontChooserPanel):

jFont = java.awt.Font('arial black',java.awt.Font.PLAIN, 8);
jFontPicker = com.jidesoft.combobox.FontComboBox(jFont);
[hjFontPicker, hContainer] = javacomponent(jFontPicker, position, gcf);
set(hjFontPicker, 'ItemStateChangedCallback', @myCallbackFunction);

popupmenu uicontrol

As another example of using a font-selection drop-down (combo-box), we can use a standard Matlab popupmenu uicontrol, setting its String property value to a cell-array containing the supported system’s fonts (as returned by the listfonts function). A nice twist here is to use the undocumented trick that all Matlab uicontrols inherently support HTML to list each of the fonts in their respective font style:

fontStr = @(font) ['' font ''];
htmlStr = cellfun(fontStr, listfonts, 'uniform',false);
uicontrol('style','popupmenu', 'string',htmlStr, 'pos',[20,350,100,20]);

Austria visit, 11-15 October, 2015

I will be travelling to clients in Austria next week, between October 11-15. If you are in Austria and wish to meet me to discuss how I could bring value to your work, then please email me (altmany at gmail).

The post Font selection components appeared first on Undocumented Matlab.