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Injected into Command service is null

• Edit

dev.div0

20 Sep, 2015 12:04 PM

Hello.
Please point to my error.
the config is:

`[Inject] public var injector:IInjector;

public function configure():void
{ injector.map(FloxService);

        commandMap.map(ConfigEvent.CONFIG_INIT_COMPLETE).toCommand(ShowIntroScreenCommand);

        commandMap.map(ScreenEvent.TO_MAIN_SCREEN_REQUEST).toCommand(ShowMainScreenCommand);
        commandMap.map(ScreenEvent.TO_INTRO_SCREEN_REQUEST).toCommand(ShowIntroScreenCommand);
        commandMap.map(ScreenEvent.SAVE_DATA_REQUEST).toCommand(SaveDataCommand);

        mediatorMap.map(IntroScreen).toMediator(IntroScreenMediator);
        mediatorMap.map(MainScreen).toMediator(MainScreenMediator);

        context.afterInitializing(initComplete);
    }

    private function initComplete():void
    {
        dispatcher.dispatchEvent(new ConfigEvent(ConfigEvent.CONFIG_INIT_COMPLETE));
    }`

Command
`public class SaveDataCommand extends Command{

[Inject]
public var service:IService;

public function SaveDataCommand() {
    trace("service = "+service);
    if(service){
        service.saveData();
    }
    else{
        trace("Service is NULL");
    }

}

} }`

Service
`package dev.div0.services { import com.gamua.flox.Flox;

public class FloxService implements IService {

public function saveGoToMainCount(count:int):void {
    Flox.logEvent("go_main_clicked", {count: count});
}

public function saveGoToIntroClick():void {
    Flox.logEvent("go_intro_clicked");
}

public function saveData():void {
    Flox.getTime(getTimeCompleteHandler, getTimeErrorHandler);
}

private function getTimeErrorHandler(error:String, httpStatus:int):void {
        trace("saveData error:"+error +".  httpStatus:"+httpStatus);
    }

    private function getTimeCompleteHandler(time:Date):void {
        new SaveData(time.toString());
    }
}

}`

in case of service's interface injection

[Inject] public var service:IService;

the error is

Error: Injector is missing a mapping to handle injection into property "service" of object "[object SaveDataCommand]" with type "dev.div0.commands::SaveDataCommand". Target dependency: "dev.div0.services::IService|"

in case of class injection

[Inject] public var service:FloxService;

service is NULL

1. Support Staff 1 Posted by Ondina D.F. on 20 Sep, 2015 12:47 PM

   

   Hi,

   injector.map(FloxService); is an incomplete mapping.

   The correct mapping would be:

   injector.map(FloxService).asSingleton();
   

   Please read the answers from the following discussions for more details:

   http://knowledge.robotlegs.org/discussions/robotlegs-2/8182-the-nec...

   http://knowledge.robotlegs.org/discussions/robotlegs-2/5766-automag...

   http://knowledge.robotlegs.org/discussions/robotlegs-2/8018-why-i-c...

   Also, be aware of the differences between the different mappings :

   toValue - Makes the mapping return the given value for each consecutive request.

   toType - Makes the mapping return a newly created instance of the given type for each consecutive request.

   toSingleton - Makes the mapping return a lazily constructed singleton instance of the mapped type for each consecutive request.

   asSingleton - Makes the mapping return a lazily constructed singleton instance of the mapped type for each consecutive request.

   asSingleton(initializeImmediately:Boolean=false) - initializeImmediately determines when the instance should be created, immediately after mapping or after the first request

   Hope this helps.
   Ondina

   • Edit

2. Support Staff 2 Posted by Ondina D.F. on 20 Sep, 2015 12:50 PM

   

   I forgot to say that if you are injecting an interface, you should map it like this:

   injector.map(IService).toSingleton(FloxService);
   

   • Edit

3. 3 Posted by dev.div0 on 20 Sep, 2015 01:21 PM

   

   Thank you.
   By the way - its my error.
   I need to override execute() method to use injected service inside Command - my inattention.

   • Edit

4. Support Staff 4 Posted by Ondina D.F. on 21 Sep, 2015 03:45 PM

   

   You're welcome!

   Concerning the execute method in commands, I didn't notice that you didn't have an execute() in your command. I spotted the incomplete mapping and didn't pay much attention to the code below it.

   So yes, injected classes will be null within a constructor, because the Injector hasn't finished its job (injection) yet:

   https://github.com/robotlegs/robotlegs-framework/wiki/common-proble...

   Just for your information, you don't need to extend the robotlegs Command class. Any class with a public execute method can be used as a Command.

   I'm going to mark this discussion as resolved, but you can re-open it, if need be, or you can create a new discussion if you need assistance on another topic.

   Ondina

   • Edit

5. Ondina D.F. closed this discussion on 21 Sep, 2015 03:45 PM.