MATLAB GUI: Tracking mouse actions

In the second tutorial of the series, we will look at how we can track the mouse actions such as pressing and releasing. We will start with the GUI we created in the first tutorial, and we will add a text field that details the last mouse action and its location.

Step-by-step guide

1. Download mouse1.zip, and ready the files in a working folder of MATLAB.
2. Open gui_mouse.fig using GUIDE.
3. Add a static text to the GUI and rename its tag to lbl_last_action
4. Open the property window of the figure (double click on the figure), click on WindowButtonDownFcn to populate the callback and paste the following code:

pos = get(hObject, 'currentpoint'); % get mouse location on figure
x = pos(1); y = pos(2); % assign locations to x and y
set(handles.lbl_last_action, 'string', ['Mouse pressed @ X: ', num2str(x), ', Y: ', num2str(y)]);

5. Click on WindowButtonUpFcn to populate the callback and paste the following code: 

pos = get(hObject, 'currentpoint'); % get mouse location on figure
x = pos(1); y = pos(2); % assign locations to x and y
set(handles.lbl_last_action, 'string', ['Mouse released @ X: ', num2str(x), ', Y: ', num2str(y)]);

6. Press F5 (or click on run button) to start up the GUI.

Anytime when the mouse is pressed (down) or released (up), the text field is updated with the action and the location of the action. Note that if the button is released quickly after pressed, the text field may be updated too quickly as if there is no press action.

Video 


Files: 

Files can be downloaded here. Note some changes have been made to the GUI to make it more presentable.

MATLAB GUI tutorial planned

I am planning to create a tutorial series on how to incorporate mouse movements and actions into MATLAB GUI. Traditionally, the GUIs are designed to accept user input via a variety of uicontrols (or components). While having the components are sufficient in most applications, there are still cases where the user experience may be drastically enhanced by utilizing mouse movements and actions.

The end-product of the series is a GUI that allows user dragging and dropping an object in the GUI. The series will contain a number of tutorials, each dealing with a specific subject (or sub-problem). Each tutorial will be built on the earlier tutorials, either provides a different functionality or a more advance usage of the same functionality (or both).

The series of tutorials may cover the following topics (subject to change)

• tracking mouse locations [completed]
• tracking mouse actions [completed]
• finding the 'hotspot' [completed]
• changing mouse pointer [completed]
• designing drag-and-drop [completed]
• implementing drag-and-drop [completed]