2- Programs in Niagara framework iot. Action Slots | Importing Modules | Niagara Developer tutorial - read the full article about IoT Development, IoT Development and Internet of Things technologies from Iot Easily on Qualified.One
hello everybody welcomes back to the Niagara framework developer tutorial today we are going to talk more about the program in Niagara, by the way, I will keep my videos to be short and brief hopefully you will like it actually I received many useful comments since I posted my first video so here I thank all of you guys for your supporting and I quoted one of the reviews which I found it useful for todays topic here is some brief points first, we dont need to package the program object unless we plan to deploy in a jar file or even there is a need to add permissions actually jarring is good as it uses less resources as the program become standard components and also remember that once the program in a jar its a component and we cant use the program editor on that component so in order to make changes we need to go back to the program module and re-build a new jar again and then re-deploy it also, we need to pay attention not to loop or hang in programs as a program object runs on the engine thread which could cause an engine watchdog timeout if they hang up the engine thread today we will talk about action slots as we have seen before in the previous video the program contains three methods which are generated automatically the first one is onStart this will be triggered after the component created or in one stage of starting the station the second one is onStop this will be triggered when the component is deleted or when the station is turning off and the last one is onExecute which will be triggered automatically when any input has been changed how about if we would like to add a new action slot actually we can add another action slot by selecting slot tab and add slot choosing the program from the type list and after then we take the class of programAction, let me rename this slot and let me say its for createPoints now we need to implement the function for this action slot by going back to the editor the function name will follow the structure of adding "on" than the name of that action slot and we need to care that the first letter is a capital letter so here we take this name and will be like on created points and then for example if we would like to add a control point programmatically to a specific location this location can be made by adding an ord object which is an object resolution descriptor for that path and in my case, I set the path under the station under the config so how we get this path we can easily go to the config and check the path so you can see this is a pass for the config station slot and in order to use ord object, we have to import that the class by going back to the imports and then import type and select under the baja we select Ord after that we need to resolve that location by calling get, so to add control point we need to import from control module first by going back to the import and selecting import type selected from the control module and under the control module we can find a BooleanPoint and by going back to the editors we can add the boolean point to that location we can see here in this function actually its easy to know what is the documentation or what is a description for that function so for instance if we need to check about this "add" function for a component we can easily go back to the help and check the help documentation and when im clicking help content and if we go to search about BComponent so we can find this action or this function inside these functions take two parameters the first is the name for that element you need to add and the element itself and if you can see the element here is BValue and in our case, its a ControlPoint which is BBooleanPoint so let me check about this BBooleanPoint.
and as you can see here in the documentation for BBooleanPoint its extended from this class and if we going through its hierarchy we can see like its really come from the BValue and extend from BComponent BComplex until we reach that BValue by the way, the action slots are designed to be invoked mainly so if we compile this code and by going and run this code we can see the point is created programmatically thats all for today thank you and I hope my video helped you guys and again if you have any question or suggestion about my future videos welcome to leave your comments below see you in the next video
Iot Easily: 2- Programs in Niagara framework iot. Action Slots | Importing Modules | Niagara Developer tutorial - IoT Development