Mosync: Detecting Pointer/Clicks - c++

Question

I am trying to detect when a Label is clicked/pointed/hit. I come from programming in Win32 C++ & Java Swing and I know both take different approaches to how you register for event/input.
I have looked at the tutorials but I cannot find an example of detecting a click. Is there a constant for a click, so then I can detect it in the keyPressEvent (Ie, like win32 & the WM_LBUTTONDOWN)? Or do I need to first register for the click then call my own function to handle the click (like Java & .addActionListener())?
My attempts to detect the click below dont work:
#include <MAUtil/Moblet.h>
#include <MAUI/Layout.h>
#include <MAUI/ListBox.h>
#include <MAUI/Label.h>
#include <MAUI/EditBox.h>
#include <MAUI/Screen.h>
#include <MAUtil/Environment.h>
#include <madmath.h>
#include <conprint.h>
using namespace MAUtil;
using namespace MAUI;
class MouseScreen : public Screen, public PointerListener
{
private:
Label *testLabel;
public:
MouseScreen()
{
MAExtent screenDim = maGetScrSize();
Layout* mainLayout = new Layout( 0, 0, EXTENT_X(screenDim), EXTENT_Y(screenDim), NULL, 1, 3 );
ListBox* mainListBox = new ListBox( 0, 0, 100, 200, mainLayout,
ListBox::LBO_VERTICAL, ListBox::LBA_LINEAR,
true );
mainListBox -> setPaddingLeft( 10 );
mainListBox -> setPaddingRight( 10 );
mainListBox -> setPaddingTop( 10 );
mainListBox -> setPaddingBottom( 10 );
mainListBox -> setBackgroundColor( 900 );
mainLayout -> setBackgroundColor( 300 );
testLabel = new Label( 10, 300, 50, 20, mainLayout );
//testLabel -> addPointerListener( this );
testLabel -> setCaption( "Click me" );
mainLayout -> add( testLabel );
}
void pointerPressEvent( MAPoint2d p )
{
printf( "clicked" ); // never occurs
// OR
if ( testLabel.contains((MouseScreen*)p) )
{
printf( "Label clicked" );
}
// Should I call parent function
// PointerListener :: pointerPressEvent( p );
}
void pointerMoveEvent( MAPoint2d p ) {}
void pointerReleaseEvent( MAPoint2d p ) {}
};
class MouseMoblet : public Moblet
{
public:
MouseMoblet()
{
instance = new MouseScreen();
instance -> show();
}
~MouseMoblet()
{
delete instance;
}
void keyPressEvent(int keyCode, int nativeCode)
{
// todo: handle key presses
printf( "Blah" ); // never occurs when I press the mouse, but other KEYS work
}
void keyReleaseEvent(int keyCode, int nativeCode)
{
// todo: handle key releases
}
private:
MouseScreen *instance;
};
extern "C" int MAMain()
{
Moblet::run(new MouseMoblet());
return 0;
};

Answer 1

I can see some things that you need to do. First, you need to set mainLayout as the main widget for Screen by calling setMain(mainLayout). This makes the screen aware of the mainLayout so that it can draw it. Once you have done this you will be able to see your widgets on the screen and you should also get click events.
In pointerPressedEvent you were almost right, the contains method of testLabel takes a point rather than a Screen. What you should do here is to call testLabel->contains( p.x, p.y ) to evaluate if the testLabel was clicked.
The full revised code looks something like this:
#include <MAUtil/Moblet.h>
#include <MAUI/Layout.h>
#include <MAUI/ListBox.h>
#include <MAUI/Label.h>
#include <MAUI/EditBox.h>
#include <MAUI/Screen.h>
#include <MAUtil/Environment.h>
#include <madmath.h>
#include <conprint.h>
using namespace MAUtil;
using namespace MAUI;
class MouseScreen : public Screen
{
private:
Label *testLabel;
public:
MouseScreen()
{
MAExtent screenDim = maGetScrSize();
Layout* mainLayout = new Layout( 0, 0, EXTENT_X(screenDim), EXTENT_Y(screenDim), NULL, 1, 3 );
ListBox* mainListBox = new ListBox( 0, 0, 100, 200, mainLayout,
ListBox::LBO_VERTICAL, ListBox::LBA_LINEAR,
true );
mainListBox -> setPaddingLeft( 10 );
mainListBox -> setPaddingRight( 10 );
mainListBox -> setPaddingTop( 10 );
mainListBox -> setPaddingBottom( 10 );
mainListBox -> setBackgroundColor( 900 );
mainLayout -> setBackgroundColor( 300 );
testLabel = new Label( 10, 300, 50, 20, mainLayout );
//testLabel -> addPointerListener( this );
testLabel -> setCaption( "Click me" );
mainLayout -> add( testLabel );
setMain( mainLayout );
}
void pointerPressEvent( MAPoint2d p )
{
if ( testLabel->contains( p.x, p.y ) )
{
printf( "Label clicked" );
}
}
void pointerMoveEvent( MAPoint2d p ) {}
void pointerReleaseEvent( MAPoint2d p ) {}
};
class MouseMoblet : public Moblet
{
public:
MouseMoblet()
{
instance = new MouseScreen();
instance -> show();
}
~MouseMoblet()
{
delete instance;
}
void keyPressEvent(int keyCode, int nativeCode)
{
// todo: handle key presses
printf( "Blah" ); // never occurs when I press the mouse, but other KEYS work
}
void keyReleaseEvent(int keyCode, int nativeCode)
{
// todo: handle key releases
}
private:
MouseScreen *instance;
};
extern "C" int MAMain()
{
Moblet::run(new MouseMoblet());
return 0;
};
Note: The current MoSync UI system was designed for non-touch phones, so it is a bit contrived to handle pointer events, this will however be improved in the coming release.
Regarding wether you should call the parent function or not depends on if you want to keep the default behavior or not, currently the default implementation of Screen does nothing.