Reference MWAPI
Learn to develop Windows applications with the new Microsoft Windowing Applications Interface (MWAPI).
TABLE OF CONTENTS Reference MWAPI
Event Specification Attributes
Each EVENT attribute node will have at least one Event Specification Attribute to modify when callback processing can occur for the specified event type. Depending on the event type specified, a second modifier can be used. ENABLE and FILTERIN are the keywords specified by the MWAPI for the restriction of callbacks, and implementers can define their own for their implementations. Implementation-defined keywords will begin with the letter "Z," and are not guaranteed portable. These attributes are maintained as subscripts of the event types they modify. Example 5.10 shows the syntax required for these modifiers. Event Specification Attributes are uppercase keywords that must be enclosed in quotes or assigned as a variable
^$W(<span class="emphasis"><iwindow name</i></span>, "G" ,<span class="emphasis"><igadget name</i></span>,"EVENT"<span class="emphasis"><ievent type,event specification attribute<span class="emphasis"><i)</i></span>=value</i></span>
EXAMPLE 5.10: Event Specification Node Syntax
The MWAPI implementation implicitly creates an ENABLE attribute node subscripted from each event type. If the value of the node evaluates to true, and event processing is active for the process, callback processing can occur for the event type specified. If the value is false, a callback will not occur for the event type. The ENABLE attribute is true by default and can be modified at anytime. Example 5.11 shows how this looks.
^$W("WIN","G","GAD","EVENT","FOCUS")="FOCUS^WINDOW"^$W("WIN","G","GAD","EVENT","FOCUS","ENABLE")=1EXAMPLE 5.11: Enabled Event Node Syntax
Events in the keyboard and pointer categories (see Table 5.12 and Table 2.2) can have restrictions placed on their ability to process callbacks even if callback processing is enabled for the event type. The event specification attribute FILTERIN...
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