EVENTS.
WML includes the possibility to do some tasks when an event
occur. For example when we go to
some card, when a specified time expires, etc.
The first event we'll explain sounds a little familiar to us (we
saw it in the last example), it performs an action
when the user press a bottom, this
<DO> element can be located at a deck (inside a template) or at a card level. As we explained before a DO inside a card can override the one located at the template.
<DO> element can be located at a deck (inside a template) or at a card level. As we explained before a DO inside a card can override the one located at the template.
The <ONTIMER> event doesn't
wait for a key press to make the task, it goes to a
URL when a specified time expires. This time must be specified with
a timer value, as you can see in the example
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "WAPs" "www.homestead.com">
<wml>
<card
id="card1" ontimer="#card2" title="WAPs">
<timer value="12"/>
<p
align="center">
<br/>
<br/> <br/>
<big>
The
WAP
</big>
</p>
</card>
<card
id="card2" ontimer="#card3" title="WAPs">
<timer
value="12"/>
<p
align="center">
<big>
The
WAP
hole
<br/>
</big>
</p>
</card>
<card
id="card3" title="WAPs" onenterforward = "#card4" >
<p
align="center">
<br/>
<br/> <br/>
<big>
<i>
The WAP
hole Sun
</i>
</big>
</p>
</card>
<card
id="card4" title="WAPs">
<p
align="center">
<br/>
<br/> <br/>
<big>
<i>
Press
Back
</i>
</big>
</p>
</card>
</wml>
As
you can see the ontimer defined in the card
element sets the url where the program goes when the time defined expires.
<ONENTERFORWARD>, What the hell is
it?
The OnEnterForward event occurs when you
enter in a deck normally (forward). For example when we go from the 2nd deck to the third one. This event
wont occur if we go from the third card to the second one (for example
with the "go back" key). In the
example we go from the card "card2" to the card labeled "card3", the event
"onenterforward" occurs and that card will not be executed, instead of
that it goes to the card specify in the
event (onenterforward = "#card4").
When the card "card4" is displayed we can go to card 3 pressing the
"go back" key, and is now when we can
see:
"The WAP hole of the SUN"
The initial card is displayed during 12 units
of time
The second card is displayed during 12 units of
time
As the onenterforward event occurs, it jumps to
the 4th card
Now pressing "Back" we came again to the third
card, but this time the event is not triggered. (it is not enter
forward)
