The receiver in Laszlo's point-to-point event system.
A delegate is an object that calls a specific method in a specific context when its execute method is called. It is essentially a function pointer.
Delegates, along with events, comprise Laszlo's point to point event system. A delegate represents a named method of an instance. Delegates are mostly registered with events, but they can be used anywhere a function callback would traditionally be called for: for instance, the LzTimer service takes a delegate as its argument when a timer is started. See the code example on the events page.
| Attributes | |||||
| Name | Usage | Type (Tag) | Type (JS) | Default | Category |
| c | JS only | Object | readonly | ||
| The context in which to call the method | |||||
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| f | JS only | String | readonly | ||
| The name of the method to call | |||||
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| constructor() | ||
| LzDelegate(context, functionName, eventSender, eventName) | ||
| Parameters | ||
| Name | Type | Desc |
| context | Object | reference to object which will be called |
| functionName | String | name of the method to call (a string) |
| eventSender | Object | optional; the sender of the event to register the new delegate for. |
| eventName | String | Optional, but required if eventSender is used; The name of the event to register the new delegate for. |
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| disable() | ||
| LzDelegate.disable() | ||
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Disables the delegate until enable method is called. |
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| enable() | ||
| LzDelegate.enable() | ||
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Enables a delegate that has been disabled |
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| execute() | ||
| LzDelegate.execute(sd) | ||
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Executes the named method in the given context with the given data. Returns the result of the call. |
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| Parameters | ||
| Name | Type | Desc |
| sd | The data with which to call the method. | |
| Returns | ||
| Type | Desc | |
| The value returned by the method call. | ||
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| register() | ||
| LzDelegate.register(eventSender, eventName) | ||
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Registers the delegate for the named event in the given context. NB: This is the primary way in which events are created. Published events do not generally exist as objects (with some exceptions) until delegates are created for them. |
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| Parameters | ||
| Name | Type | Desc |
| eventSender | Object | The object which publishes the event. |
| eventName | String | The name (string) of the event to register for. |
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| unregisterAll() | ||
| LzDelegate.unregisterAll() | ||
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Unregisters the delegate for all of the events it is registered for. |
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| unregisterFrom() | ||
| LzDelegate.unregisterFrom(event) | ||
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Unregisters the delegate for the given event |
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| Parameters | ||
| Name | Type | Desc |
| event | LzEvent | The event to unregister the delegate from. (e.g. myview.onmouseup) |
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