Attaching a Channel - Revision history

Mparadis: /* Attach Event */

2022-04-19T20:28:20Z

Attach Event

← Older revision		Revision as of 20:28, 19 April 2022
Line 87:		Line 87:
	ch.onAttach = function() {		ch.onAttach = function() {
	// You can access the Phidget that fired the event using this function's parameter		// You can access the Phidget that fired the event using this function's parameter
	let deviceSerialNumber = ch.deviceSerialNumber		let deviceSerialNumber = this.deviceSerialNumber
	}		}
	</syntaxhighlight>		</syntaxhighlight>

Mparadis at 20:21, 19 April 2022

2022-04-19T20:21:20Z

← Older revision		Revision as of 20:21, 19 April 2022
Line 80:		Line 80:
	\|-\|		\|-\|
	JavaScript=<syntaxhighlight lang=javascript>		JavaScript=<syntaxhighlight lang=javascript>
	// Declare the event ~~handler~~
	function ~~onAttachHandler~~ (ch) {		// Declare your object. Replace "DigitalInput" with the object for your Phidget
			const ch = new phidget22.DigitalInput()

			// Assign the handler that will be called when the event occurs
			ch.onAttach = function() {
	// You can access the Phidget that fired the event using this function's parameter		// You can access the Phidget that fired the event using this function's parameter
	~~var~~ deviceSerialNumber = ch.~~getDeviceSerialNumber()~~		let deviceSerialNumber = ch.deviceSerialNumber
	}		}
	~~...~~
	~~// Declare your object. Replace "DigitalInput" with the object for your Phidget~~
	~~var ch = new phidget22.DigitalInput()~~
	~~...~~
	~~// Assign the handler that will be called when the event occurs~~
	~~ch.onAttach = onAttachHandler~~
	</syntaxhighlight>		</syntaxhighlight>
	</tabber>		</tabber>

Mparadis at 21:19, 24 March 2021

2021-03-24T21:19:16Z

← Older revision		Revision as of 21:19, 24 March 2021
Line 96:		Line 96:
	The attach event handler should be set '''before''' the channel is opened; otherwise, the attach event could occur before the handler is set to deal with it.		The attach event handler should be set '''before''' the channel is opened; otherwise, the attach event could occur before the handler is set to deal with it.

	==Can I Attach the Same Channel Multiple ~~Times~~?==		==Can I Attach the Same Channel in Multiple Programs?==
	Any one physical channel can only be attached to one software channel at a time. This remains true across multiple programs. For example, if you connected a single Phidget Accelerometer to a computer, and ran two copies of the same program to open that Accelerometer at the same time, only the first program would attach, while the other would remain ''open'' but not ''attached''. If the ''attached'' channel were to be closed, the other program would then attach to the Accelerometer.		Any one physical channel can only be attached to one software channel at a time. This remains true across multiple programs. For example, if you connected a single Phidget Accelerometer to a computer, and ran two copies of the same program to open that Accelerometer at the same time, only the first program would attach, while the other would remain ''open'' but not ''attached''. If the ''attached'' channel were to be closed, the other program would then attach to the Accelerometer. In fact, if the device has other devices connected to it (e.g. a VINT Hub with many Phidgets connected), attaching a channel from any device in one program will prevent any of the channels on the entire Hub from attaching in the other program.

	'''The one exception''' is if the Phidget device channel is ''attached'' over the network through the '''Phidget Network Server'''. Multiple software channels are allowed to match and attach to the hardware channel over the network. Some Phidgets, such as motor controllers will never match more than one channel at a time, for safety reasons.		'''The one exception''' is if the Phidget device channel is ''attached'' over the network through the '''Phidget Network Server'''. Multiple software channels are allowed to match and attach to the hardware channel over the network. Some Phidgets, such as motor controllers will never match more than one channel at a time, for safety reasons.


	{{Flow_Navigation_Buttons\|{{Flow Page Number\|{{PAGENAME}} }} }}		{{Flow_Navigation_Buttons\|{{Flow Page Number\|{{PAGENAME}} }} }}

Mparadis at 16:58, 15 March 2021

2021-03-15T16:58:42Z

← Older revision		Revision as of 16:58, 15 March 2021
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	{{Recommended_Flow_Links\|{{Flow Page Number\|{{PAGENAME}} }} }}		[[Category:Programming]]{{Recommended_Flow_Links\|{{Flow Page Number\|{{PAGENAME}} }} }}

	When a channel is open (and not ''attached''), the system will continue to try to match it with a		When a channel is open (and not ''attached''), the system will continue to try to match it with a

Mparadis at 15:44, 9 April 2019

2019-04-09T15:44:49Z

← Older revision		Revision as of 15:44, 9 April 2019
Line 80:		Line 80:
	\|-\|		\|-\|
	JavaScript=<syntaxhighlight lang=javascript>		JavaScript=<syntaxhighlight lang=javascript>
	//Declare your object. Replace "DigitalInput" with the object for your Phidget		// Declare the event handler
			function onAttachHandler (ch) {
			// You can access the Phidget that fired the event using this function's parameter
			var deviceSerialNumber = ch.getDeviceSerialNumber()
			}
			...
			// Declare your object. Replace "DigitalInput" with the object for your Phidget
	var ch = new phidget22.DigitalInput()		var ch = new phidget22.DigitalInput()
			...
	//~~Declare and assign~~ the ~~event~~ handler		// Assign the handler that will be called when the event occurs
	~~ch.onAttach = function (ch) {~~		ch.onAttach = onAttachHandler
	~~// You can access the Phidget~~ that ~~fired~~ the event ~~using parameter of this event handler ("ch" in this case)~~
	~~var deviceSerialNumber =~~ ch.~~getDeviceSerialNumber()~~
	};
	</syntaxhighlight>		</syntaxhighlight>
	</tabber>		</tabber>

Mparadis at 20:29, 5 April 2019

2019-04-05T20:29:01Z

← Older revision		Revision as of 20:29, 5 April 2019
Line 85:		Line 85:
	//Declare and assign the event handler		//Declare and assign the event handler
	ch.onAttach = function (ch) {		ch.onAttach = function (ch) {
	// You can access the Phidget that fired the event using parameter of this event handler ("ch" in this case)		// You can access the Phidget that fired the event using parameter of this event handler ("ch" in this case)
	var deviceSerialNumber = ch.getDeviceSerialNumber()		var deviceSerialNumber = ch.getDeviceSerialNumber()
	};		};

Mparadis at 20:28, 5 April 2019

2019-04-05T20:28:39Z

@@ Line 77: / Line 77: @@
 //Assign the handler that will be called when the event occurs
 Phidget_setOnAttachHandler((PhidgetHandle)ch, onAttachHandler, NULL);
 </syntaxhighlight>
 </tabber>

Jdecoux: Created page with "{{Recommended_Flow_Links|{{Flow Page Number|{{PAGENAME}} }} }} When a channel is open (and not ''attached''), the system will continue to try to match it with a Phidget devic..."

2019-02-28T20:04:43Z

Created page with "{{Recommended_Flow_Links|{{Flow Page Number|{{PAGENAME}} }} }} When a channel is open (and not ''attached''), the system will continue to try to match it with a Phidget devic..."

New page

{{Recommended_Flow_Links|{{Flow Page Number|{{PAGENAME}} }} }}

When a channel is open (and not ''attached''), the system will continue to try to match it with a
Phidget device channel until either a match is found, or the channel is closed. During this time, your program will remain unable to interact with the Phidget channel, as no physical channel has yet been linked to the software one.

When the software channel is matched with a physical channel, the channel is ''attached'' and an <code>Attach</code> event is fired.

==Attach Event==

An event handler can be registered to catch the <code>Attach</code> event. Each channel also has an <code>Attached</code> property that can be read to determine if the channel has been matched to a physical channel.

The following examples show how to set an event handler to detect the <code>Attach</code> event:

<tabber>
Python=<syntaxhighlight lang=python>
#Declare the event handler
def onAttachHandler(self):
#You can access the Phidget that fired the event using the "self" parameter
ph = self
deviceSerialNumber = ph.getDeviceSerialNumber()
...
#Declare your object. Replace "DigitalInput" with the object for your Phidget
ch = DigitalInput()
...
#Assign the handler that will be called when the event occurs
ch.setOnAttachHandler(onAttachHandler)
</syntaxhighlight>
|-|
Java=<syntaxhighlight lang=java>
public static DigitalInputAttachListener onAttach = new DigitalInputAttachListener() {
@Override
public void onAttach(AttachEvent e) {
//You can access the Phidget that fired the event by calling "getSource()"
//on the event parameter.
//Replace "DigitalInput" with the object for your Phidget.
DigitalInput ph = (DigitalInput) e.getSource();
int deviceSerialNumber = ph.getDeviceSerialNumber();
}
};
...
//Declare your object. Replace "DigitalInput" with the object for your Phidget.
DigitalInput ch;
...
//Assign the event listener that will be called when the event occurs
ch.addAttachListener(onAttach);
</syntaxhighlight>
|-|
C#=<syntaxhighlight lang=cSharp>
//Declare the event handler
void attach(object sender, Phidget22.Events.AttachEventArgs e) {
//You can access the Phidget that fired the event by typecasting "sender"
//to the appropriate Phidget object type.
//Replace "DigitalInput" with the object for your Phidget.
DigitalInput ph = ((DigitalInput)sender);
int deviceSerial = ph.DeviceSerialNumber;
}
...
//Declare your object. Replace "DigitalInput" with the object for your Phidget.
DigitalInput ch;
...
//Assign the handler that will be called when the event occurs
ch.Attach += attach;
</syntaxhighlight>
|-|
C=<syntaxhighlight lang=c>
//Declare the event handler
static void CCONV onAttachHandler(PhidgetHandle ph, void *ctx) {
//You can access the Phidget that fired the event by using the first parameter
//of the event handler
int deviceSerialNumber;
Phidget_getDeviceSerialNumber(ph, &deviceSerialNumber);
}
...
//Declare your object. Replace "PhidgetDigitalInputHandle" with the handle for your Phidget object.
PhidgetDigitalInputHandle ch;
...
//Assign the handler that will be called when the event occurs
Phidget_setOnAttachHandler((PhidgetHandle)ch, onAttachHandler, NULL);
</syntaxhighlight>
</tabber>

The attach event handler should be set '''before''' the channel is opened; otherwise, the attach event could occur before the handler is set to deal with it.

==Can I Attach the Same Channel Multiple Times?==
Any one physical channel can only be attached to one software channel at a time. This remains true across multiple programs. For example, if you connected a single Phidget Accelerometer to a computer, and ran two copies of the same program to open that Accelerometer at the same time, only the first program would attach, while the other would remain ''open'' but not ''attached''. If the ''attached'' channel were to be closed, the other program would then attach to the Accelerometer.

'''The one exception''' is if the Phidget device channel is ''attached'' over the network through the '''Phidget Network Server'''. Multiple software channels are allowed to match and attach to the hardware channel over the network. Some Phidgets, such as motor controllers will never match more than one channel at a time, for safety reasons.

{{Flow_Navigation_Buttons|{{Flow Page Number|{{PAGENAME}} }} }}