Mali GPU User Interface Engine Application Development Guide

Tutorial on the System ClassesExample 2-3 Reading keyboard input...printf("Press ESC to continue\n");while (true){if (keyboard->getSpecialKeyState(MDE::Keyboard::KEY_ESCAPE)) break;}...keyboard->release();Because the Keyboard object in Example 2-2 on page 2-3 was not created with theManaged template, you must explicitly call release() on the keyboard interface.4. Example 2-4 shows the next stage of the application that deliberately raises an exceptionby trying to create a non-existent file system:Example 2-4 Basic exception handling...try{MDE::Managed fs = system->createFileSystem("non-existing root");fs->createInputStream("non-existing file");}}catch (MDE::Exception& e){printf("An expected exception was thrown:\n%s\n", e.getMessage().getCharString() );}You can put the standard C++ try blocks around code that you are testing.Exceptions generated by the UI Engine have types derived from MDE::Exception. Use acatch(MDE::Exception) statement to catch all exceptions generated by the UI Engine. Forexample code, ARM recommends putting a try block around all of the code in main() asshown in Example 2-5:Example 2-5 Using a try catch blockmain(){try{// all executable code}catch (MDE::Exception& e){// exception handling code}}5. Compile and run the project to test keyboard input and exception trapping. Figure 2-1 onpage 2-5 shows the system window:ARM DUI 0527A-02a Copyright © 2010 ARM. All rights reserved. 2-4ID070710Non-Confidential - Draft - Beta