网上常用的方法：

if ~isdeployed

newIcon=javax.swing.ImageIcon('.piciap.jpg');

else

newIcon=javax.swing.ImageIcon('iap.jpg');

end

jFrame = get(hObject,'javaframe');

jFrame.setFigureIcon(newIcon);

运行后warning：

Warning: figure JavaFrame property will be obsoleted in a future release. For more information see the JavaFrame resource on the MathWorks Web site.

新方法 (http://www.mathworks.com/matlabcentral/answers/7313-change-guide-icon)：

if ~isdeployed

newIcon=javax.swing.ImageIcon('.piciap.jpg');

else

newIcon=javax.swing.ImageIcon('iap.jpg');

end

jFrame = get(handle(hObject),'javaframe');

jFrame.setFigureIcon(newIcon);