MATLAB IMAGE ACQUISITION TOOLBOX - RELEASE NOTES Guide de l'utilisateur télécharger pdf (Page 117)

Creating Device Properties

6-5

Creating Device Properties

To define properties for a device, follow this procedure:

Create the property using the appropriate IPropFactory member function for

the data type. The engine passes in a handle to a IPropFactory object to the

getDeviceAttributes() function.

For example, to create a property of type double, use the

createDoubleProperty() method of the IPropFactory object, specifying the

property name and default value as arguments.

hprop = devicePropFact->createDoubleProperty("Brightness",100)

The IPropFactory class supports functions to create properties of various data

types — see “Selecting the Property Creation Function” on page 6-5.

Specify if a user can modify the property, using the setPropReadOnly()

method of the IPropFactory object. Use one of the following constants

(defined in IEngine.h): READONLY_ALWAYS, READONLY_NEVER, and

READONLY_WHILE_RUNNING. For example,

devicePropFact->setPropReadOnly(hProp,

imaqkit::propreadonly::READONLY_WHILE_RUNNING);

Add the property to the device-specific property container, using the

addProperty() method of the IPropFactory object. For example,

devicePropFact->addProperty(hProp);

where hProp is a handle to the property you created in step 1.

Selecting the Property Creation Function

The IPropFactory() object supports functions that you can use to create properties of

various data types, including:

• int

• double

• string

• Enumerated types

1 2 ... 112 113 114 115 116 117 118 119 120 121 122 ... 171 172

Pas de commentaire

MATLAB IMAGE ACQUISITION TOOLBOX - RELEASE NOTES Guide de l'utilisateur Page 117