@@meolivares06 hi :) of course you can. You can buy it as usually and your local currency will be automatically converted during the purchase to Euro with a current exchange rate.
Hi!! Your videos are great as always, for the last 2 weeks I been trying to buy one of your courses (Advance forms), but I cant buy it, my card is being declined every time, I dont know why if already bought one of your courses before and I dont think its a problem with my bank, Im always buying stuff from internet xd
Can you help me please? I can't bind Custom Control to emitEvent: false; I use Custom Control, but i need to "correct" some of inputs. So when user input smth - i can alter it, with setValue(value, {emitEvent:false}). It works with normal forms, but with Custom Form Control i read that updateValueAndValidity used ignoring "emitEvent" option with Custom Control. So what to do, to make emitEvent: false work? Or what method use, to replace it?
Since this video came out I used this approach in two projects and I really love it. One thing that is missing for pretty much all dynamic form videos, tutorials and courses is to be able to dynamically hide or show a control based on another ones value. If you happen to know a solid solution for that, please make a video or add it to your course. In your course you already have a section about creating a form based on a json, but no way of adding conditions for visibility. I found a working solution, but it relies on mutability. For those wondering: I'm using a signal to hold the config of the form which includes a visibility state as well as conditions on when to show certain fields. Then I'm building a form based on that condition using the approach from this video. That way we can keep markup and from group in sync. Then I'm listening to value changes on the form group and look for any controls that might need to be updated. I then set their visibility to either true or false. However, since my config can be deeply nested I'm extracting all controls, that dependent on a another one, into a computed signal. I use this as a base to find controls to check and modify.
Good little dive into intervals - the ControlContainer, but honestly, it looks like you are on your way to reinvent the wheel - namely the template driven forms
Hi Dmitry, I am really glad to hear your opinion, thank you 🙌 indeed, the inspiration for self-registered form control models I found in Template-Driven forms :) I know that with TDF it would be even easier to reuse the controls since the control registration happens there automatically but sometimes we just have to stick with reactive forms.
@@Emekaelo Without declaring form controls in parent component you will face an error. Of cource you can make those controls optional, but it's not the best solution. If you want to make the child component strictly typed, it can be not that easy )
Рік тому
I used to pass the form around to huge component hierarchies... I didn't know you could avoid it. I'll never struggle again, thanks so much!
Interesting approach, previously in such cases I used Control value accessor. I think this has one advantage, we can keep the model reference in the main form model
ControlValueAccessor might be also a valid approach. It depends on the use case. CVA is useful when you want to make a component bindable with FormControl/FormGroup models which eventually brings support of angular form features like validations, etc.
best advanced angular tutorials on youtube, high quality content. You cover advanced concepts in an understandable way. i am absolutly grateful for your service to the community I will definitly buy the forms course ;)
Nice approach, thanks, will definitely use in our project! How do you deal with the fact that nested part is invisible when inspecting a form declaration in the parent component, do you usually check the template as well?
this is a good question. I think you should look always for some balance. For example, how much I will win if apply this technique for a simple login form? Well, probably not too much, right? It will bring too much magic to your forms. But maybe if it is a complex piece of logic that would require a lot of boilerplate, validation logic, etc. Then probably a bit of magic isn't so bad 😊 Also, you can use only part of the whole pattern (providing only ControlContainer) and keep separately form models and the view if you want/need.
Thanks for the great tutorial. I have been trying to do this cleanly for a long time ! Would be interesting to have some testing strategies for the subform component, as it needs to be part of a encapsulating formgroup to be functionnal.
What is next and very challenging is when you have Form Array: 1. Edit mode - you have database data which needs to populate the child reactive form array. Or not if we are in Add mode. 2. Send additional data to child component. Ex: Form array object has select box which requires some database objects and also determine values of another control in that Form Array. In the end you have two @Input, the edit mode array from database and additonal values for select box, which need to communicate with parent form group. I don't know if I will find this in the course. Nevertheless, thank you! Best one yet!
So funny, I was facing such problem yesterday, and was using 'dirty' method to solve the problem. It looks pretty awesome and I think this thing will become more popular because of your contribution :)
Thank you Dmytro, you're producing a really great and unique piece of content. Secondly, although I really like this approach in some cases, I wonder if it doesn't break the typed forms. What if I would like to have a multistep form (order) with items and addresses as separate form groups? I would like to know it upfront, validate everything etc. And with this approach the starting form group has only single field. I feel CVA would be a better choice. So my question - is there a way to use type in root component with the approach you demonstrated?
Sorry Dymtro but I think this solution you have provided this time, even if it works, is not the best approach to solve this kind of problems. For example, what if you want to add a different set of validators on each of the reused components? You would have to start creating new inputs on the reusable component to address this kind of things and everything would be a mess inside the component sooner or later. And what is worst, you don't need that, Angular is ready for those scenarios. I'm sure that you're aware that NG_VALUE_ACCESSOR provider and implementing the ControlValueAccesor interface should be the way to go if you want to create truly reusable form components, exactly the same way is done in the Angular forms source code. Adding controls "magically" to a parent formgroup from a control that is not declared as a formControl itself seems to me a really bad patttern and I hope no external library does it in my projects.
Hi, thank you for your comment and I respect it a lot. Firstly, I'd like to say that please don't take my solution as a "silver bullet" for each use case of "form control reusing" :) The best approach may vary depending on the requirements and goals you want to achieve. The goal of ControlValueAccessor isn't making the form control reusable (though it is also possible) but rather making a component/directive/DOM element/etc. behave as a form control that can support validation and other Angular form control features. Also, if you look at the source code of angular forms, you will see that the ValueAccessor is used to build a "bridge" between native form controls like input and the model (FormControl) that describes this input but it is not used for sharing purposes. The pattern from this video works better if you have a static and predictable group of controls that just has to be shared in some other place. Like the use case with billing and delivery address. If we assume that they are static and have the same validators I don't see any problem with encapsulating everything in one component and I don't see any reason to make the host component as the CVA. If the "magic" embarrasses you, you can drop this part of the pattern and define models explicitly from the parent component, it is also fine :) I also don't like when too much magic happens but if an adequate amount of magic can bring much cleaner code then I am fine with that. For example, when you build your form dynamically, it is very convenient when the component registers the corresponding form control by itself and you don't have to separately manage the form control models and the control component. By the way, Template-Driven forms are doing pretty much the same ;) E.g ngModel creates a FormControl instance and registers them in the parent FormGroup instance created by ngForm directive, so Template-Driven Forms are completely built with this "magic" and many developers like and successfully use them. Of course, we can have different opinions on it and I respect it. It is absolutely OK to have different points of view and I am very grateful for this interesting discussion :)
@@DecodedFrontendHi Dmytro. I found a solution to the problem of reusable forms on angular university article about custom controls. I dont know is it the best solution (learning angular about 2 months), but the solution helped me
@@DecodedFrontend I've got to agree with @gonzalocorchon6509 and I would like to point out that there are some issues with this approach: - controlKey when propagated through the codebase will become something the new developpers should learn in order to be able to work. It increases the entry cost of the codebase. - With this approach you will have not only to add validators and extra inputs to fullfill the features that reactive froms already have, but you have to introduce some error management. In your code, if the parent doesn't have a formGroup, your error will be a null injector instead of the well formatted form of angular, whilest with ControlValueAccesor you'll benefit of angular's error management. With that being said, I would like to thank you for your content, it's truely amazing, this critic is meant for us all to grow as a community and not discrediting your hard work, I understand a vidéo like this took you hours to make, and I think I can speak for everyone when I say, we truely appreciate your hardwork
Totally agree with you (see my comment above) and after a few experiments I would also add that (1) ControlValueAccessor gives a bit more flexibility when working with strongly typed form group definitions generated from API types (for example, ToFormGroupType) (2) better way of creating reusable components for arrays in case if you need a bit more code than simple *ngFor (3) ControlValueAccessor-based approach doesn't care about lifecycle hooks in contrast to Dmytro's example where you can't start adding controls in constructor directly, this means that parent component can't start pushing data before OnInit has finished. BUT ControlValueAccessor comes at a cost of way more complicated code and also has a few other issues like propagating control's validity upstream if you have validators inside ControlValueAccessor-based component.
This is so good, thanks for the video! creating a separate component that implements ControlValueAccessor and Validator stuff, just to containt an inner FormGroup and behave as a control also works the same, but this method is so much less painful. How does this work with typed form though, if a child component is registering the FormControls on the parent FormGroup directive, and it is all configured in the remplate? To me it seems the parent will not know about the existence of those controls, as far as typing goes - it will ofc work in runtime just as the video shows.
Hi Dmytro, How do you overcome the famous "Expression Changed After Checked" console error, in case you use in you main form template expressions like: "form.valid", since you are changing your parent component from a child(when you add the control)??
Thanks for video. I found an interesting thing here, So if we have some async validators, after each on destroy of our control we will fire updateValueAndValidity under the hood, and make some request. Maybe you know some workaround for this?
Hi, thank you for the video! Really good! But I have a question. How can I reset the complete Form in the Parent Component? Calling reset on the Parent Container set the forms added by the child to null?
Hey! Thanks for your question :) You reset the form the same way as for the regular one. This is because the formControl created by the child component will be eventually registered in the parent formGroup, so it means that if you reset the root formGroup then all child form controls will be reset to null (or initial values)
its dont work in angular 12? viewProviders: [ { provide: ControlContainer, useFactory: () => inject(ControlContainer), deps: [[new SkipSelf(), ControlContainer]], }, ], circular Circular dependency in DI detected for ControlContainer
Excellent explanation of this approach! However, if you're going to create the nested form group instance within the child component itself (instead of within the parent component's form group) like this: this.addressFormGroup = new FormGroup(...), wouldn't it be the same thing if you used [formGroup]="addressFormGroup" instead of [formGroupName]="controlKey" in the child component template, since in both cases, the template will be bound to the same nested form group instance? This way, you wouldn't need to use that "rare" feature with viewProviders to make the [formGroupName] work in the template for binding to the correct nested form group instance. Or is there some extra functionality about FormGroupName directive that FormGroup directive does not have?
Дмитрий, привет! Отличное видео! Помню ты был в очках, сделал коррекцию? Все тоже думаю избавиться от очков, но слышал, что после коррекции нужно не давать нагрузку на глаза, например, не сидеть долго за компьютером. P.S. не смог пройти по ссылке на курс.
Привет! Спасибо за отзыв о видео 😊 Да, я в апреле сделал коррекцию. Мне в клинике сказали, что лучше пару дней отдохнуть, а потом в обычном режиме можно работать. Там ещё многое зависит от метода. Я делал SMILE и после него на много быстрее восстановление. Я, кажется, отвечал уже в первый день на письма)) В любом случае, всё прошло хорошо, и пока полёт нормальный. Я очень рад! Какая именно ссылка не работает? Та что в описании или в комментарии? Я проверил, обе вроде работают ок. Пока можешь попробовать прямой линк - courses.decodedfrontend.io/courses/advanced-angular-forms?coupon=UA-cam_DISCOUNT_2023
We have a parent component with several child components, several of which are further nested, and it's ReactiveForm. Instead of implementing CVA for every child component, or using Inputs/Outputs, we are using FormGroupDirective. So into every child component, that is a part of the form, we inject the FormGroupDirective and add the control to the parent form. Have you seen this approach? I would like to double-check somewhere whether this approach is okay and not breaking good practices :D And what would be a better approach, FormGroupDirective or your in the video?
Thanks for the lesson, it is really cool. Is it possible to use the same approach without adding a new FormGroup, but add just one control to the parent FormControl?
You have amazing skills both coding and teaching although I do not like the reactive way for handling forms. It seems that, when going reactive we're doing job that the framework should do for us.
Another cool video, or should I say: a missing part of Angular docs! I finally understood the resolution decorators Thanks!. Given that the main form model (in this case: AppComponent) is incomplete (the remaining fields are dispersed across other components), how is this going to work with strongly typed forms? Also, if I wanted to author a form AddressGroupComponent that is usable in both ReactiveForms and template driven forms - would I have to author two separate components? I think Angular forms got a bit neglected over time.
Yes, but there is a nuance: FormGroupDitective is referencing always the root formGroup. When you have nested form groups then you might get unexpected behavior because controls will be always registered in the root formGroup:)
Hello @DecodedFrontend, your advanced concepts videos are very helpful. Can you please create a tutorial on how to build a Realtime Video chat web app in Angular 14 using webrtc protocol.
Thanks for your question:) Custom Form Control (aka ControlValueAccessor) is needed when you want to make a regular component behave as a form control and support corresponding features like validation. The pattern from the video is good for extracting a normal form control into some wrapper for reusing purpose.
Thanks for your feedback:) Well, actually, the alternative to option 1 is only the part with viewProviders e.g at 11:55. The rest is an addition which is optional and make sense only for specific use cases like dynamically created forms, etc
This seems cool, but I'm kinda afraid of using it since it's not the standard way of doing it. Who knows if this API is going to work the same in the next version?
Idk why you would use this instead of a proper CVA implementation of an address component. Seems like what you are doing here is a hack built atop of the ControlContainer. Got rid of boiler-plate code in one place, added a ton of it in another. Also have concerns about form validation. How would you validate this control against the parent form, for example the FormControl is marked as required in the parent group, how would you propagate that? What about setting disabled state of the delivery address FormGroup from the parent FormGroup? All this is covered by the ControlValueAccessor and Validator interfaces, and you hook your custom component into the ReactiveForms API directly so you can use [formControl] and [formControlName] directives directly on the component, not inventing custom inputs like [controlKey]. This would be a nightmare to maintain imo.
What if I need to disable one of the addresses fields from the parent component? Since the address form is being created from the address form component, the parent form (from app component) doesn't know that it exists, right? At least at Typescript level. Or am I missing something?
very nice, Thanks for sharing. But I've one question thou, how about creating a standalone component with sevral different html, how do use change this component html template dynamically?
Thank you for your efforts and sharing knowledge, great content as always and really appreciated I'm currently working on forms enhancement and reusablility especially the form validation and custom form controls validation messages And I had a question, after this video they've become two 😂 It is about that is it possible to create a custom directive for example "controlErrorHandler" to use on form controls and it can inject the validation message component like in my case as im using angular material Is it even applicable that way or there any other better solution, any advice I'd be grateful The second question came to my mind that you've fixed my problem without even seeing a directive on the controls or inputs and im really curious. Thanks in advance.
I was looking for the similar stuff and it really helped me. thanks Alot. also i am trying to write unit test cases for same standalone component and its throwing error on this saying "no provider for ControlContainer". Any idea how to fix that i created one mockClass but not working.
Hi! Thanks you for share this amazing feature. I 've two questions. I use this approach to create reusable input field (text/email/number and so on), select, radio etc... The reside in separate file and pass in input [controlKey], to the inputFiled component ([formControlName]="controlKey") and the magic appear. So the question is, what do you think about my solution? It's overkill? There is a simple one solution? Can I ask you what you think about compare your solution with the FormGroupDirective for create reusable form?
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Is there any way to buy the course from Brasil? I have only brasillians real
@@meolivares06 hi :) of course you can. You can buy it as usually and your local currency will be automatically converted during the purchase to Euro with a current exchange rate.
Hi!! Your videos are great as always, for the last 2 weeks I been trying to buy one of your courses (Advance forms), but I cant buy it, my card is being declined every time, I dont know why if already bought one of your courses before and I dont think its a problem with my bank, Im always buying stuff from internet xd
Can you help me please? I can't bind Custom Control to emitEvent: false;
I use Custom Control, but i need to "correct" some of inputs. So when user input smth - i can alter it, with setValue(value, {emitEvent:false}). It works with normal forms, but with Custom Form Control i read that updateValueAndValidity used ignoring "emitEvent" option with Custom Control.
So what to do, to make emitEvent: false work? Or what method use, to replace it?
High quality content!
Angular community is lucky having you!
Keep up the good work!
Thank you :) I happy to hear that my content helps
the best angular teacher in the whole youtube
Thank you so much! :)
Дуже корисне відео, дякую, Дмитро! Дізнаюся багато нового із ваших відео, туторіали зрозумілі, актуальні, дуже подобається ваш канал!
Best Angular youtuber. Congratulations on your channel. Keep going the great work!
Glad to hear that! Thank you so much:)
Amazing video as always. I appreciate what you do and wouldn’t be where I am today without your help!
Thank you so much for your feedback 🙌
Since this video came out I used this approach in two projects and I really love it.
One thing that is missing for pretty much all dynamic form videos, tutorials and courses is to be able to dynamically hide or show a control based on another ones value. If you happen to know a solid solution for that, please make a video or add it to your course. In your course you already have a section about creating a form based on a json, but no way of adding conditions for visibility. I found a working solution, but it relies on mutability.
For those wondering: I'm using a signal to hold the config of the form which includes a visibility state as well as conditions on when to show certain fields. Then I'm building a form based on that condition using the approach from this video. That way we can keep markup and from group in sync. Then I'm listening to value changes on the form group and look for any controls that might need to be updated. I then set their visibility to either true or false. However, since my config can be deeply nested I'm extracting all controls, that dependent on a another one, into a computed signal. I use this as a base to find controls to check and modify.
so thankful for this awesome content ! greetings from Egypt
NICE VIDEO, IT REALLY HELPED ME. THANK YOU!
Good little dive into intervals - the ControlContainer, but honestly, it looks like you are on your way to reinvent the wheel - namely the template driven forms
Hi Dmitry, I am really glad to hear your opinion, thank you 🙌 indeed, the inspiration for self-registered form control models I found in Template-Driven forms :) I know that with TDF it would be even easier to reuse the controls since the control registration happens there automatically but sometimes we just have to stick with reactive forms.
Once again, thank you very much for this excellent video. The explanations are precise and very well illustrated. You are the boss.
It's a nice approach, but would probably have issues with using strictly typed forms
I'm curious about what issues it'll have
@@Emekaelo Without declaring form controls in parent component you will face an error. Of cource you can make those controls optional, but it's not the best solution. If you want to make the child component strictly typed, it can be not that easy )
I used to pass the form around to huge component hierarchies... I didn't know you could avoid it. I'll never struggle again, thanks so much!
Interesting approach, previously in such cases I used Control value accessor. I think this has one advantage, we can keep the model reference in the main form model
ControlValueAccessor might be also a valid approach. It depends on the use case. CVA is useful when you want to make a component bindable with FormControl/FormGroup models which eventually brings support of angular form features like validations, etc.
Very helpful thanks
You are awesome dude. Perfect solution. Thanks a lot!
Ok, you're awesome. Not often people make me subscribe them, keep it up!
Nice video, I will investigate this solution in more detail, thank you continue as well 💪
Useful lesson!
best advanced angular tutorials on youtube, high quality content. You cover advanced concepts in an understandable way. i am absolutly grateful for your service to the community
I will definitly buy the forms course ;)
Nice approach, thanks, will definitely use in our project!
How do you deal with the fact that nested part is invisible when inspecting a form declaration in the parent component, do you usually check the template as well?
this is a good question. I think you should look always for some balance. For example, how much I will win if apply this technique for a simple login form? Well, probably not too much, right? It will bring too much magic to your forms. But maybe if it is a complex piece of logic that would require a lot of boilerplate, validation logic, etc. Then probably a bit of magic isn't so bad 😊 Also, you can use only part of the whole pattern (providing only ControlContainer) and keep separately form models and the view if you want/need.
Thanks for the great tutorial. I have been trying to do this cleanly for a long time !
Would be interesting to have some testing strategies for the subform component, as it needs to be part of a encapsulating formgroup to be functionnal.
Great video! It solved my split form issue. However, do you mind addressing the test case for this as well?
. I appreciate man<
I have never ever saw teacher like you
when i had see this video i become exited to tell you realy apprecite it of you
Thank you! I am happy to hear that my work is useful 😊
You've got some of the best content on Angular, thank you
dude i loved ur accent!!!!!1 thanks a lot, and keep going.
What is next and very challenging is when you have Form Array:
1. Edit mode - you have database data which needs to populate the child reactive form array. Or not if we are in Add mode.
2. Send additional data to child component. Ex: Form array object has select box which requires some database objects and also determine values of another control in that Form Array.
In the end you have two @Input, the edit mode array from database and additonal values for select box, which need to communicate with parent form group.
I don't know if I will find this in the course. Nevertheless, thank you! Best one yet!
So funny, I was facing such problem yesterday, and was using 'dirty' method to solve the problem. It looks pretty awesome and I think this thing will become more popular because of your contribution :)
It would be great to make a video about accessability. like how to change font-size for the whole application.
Thank you. very useful content.
Thank you Dmytro, you're producing a really great and unique piece of content.
Secondly, although I really like this approach in some cases, I wonder if it doesn't break the typed forms. What if I would like to have a multistep form (order) with items and addresses as separate form groups? I would like to know it upfront, validate everything etc. And with this approach the starting form group has only single field. I feel CVA would be a better choice.
So my question - is there a way to use type in root component with the approach you demonstrated?
Really thank you man! greatings from Argentina! have a nice day!
Sorry Dymtro but I think this solution you have provided this time, even if it works, is not the best approach to solve this kind of problems. For example, what if you want to add a different set of validators on each of the reused components? You would have to start creating new inputs on the reusable component to address this kind of things and everything would be a mess inside the component sooner or later. And what is worst, you don't need that, Angular is ready for those scenarios. I'm sure that you're aware that NG_VALUE_ACCESSOR provider and implementing the ControlValueAccesor interface should be the way to go if you want to create truly reusable form components, exactly the same way is done in the Angular forms source code. Adding controls "magically" to a parent formgroup from a control that is not declared as a formControl itself seems to me a really bad patttern and I hope no external library does it in my projects.
Hi, thank you for your comment and I respect it a lot.
Firstly, I'd like to say that please don't take my solution as a "silver bullet" for each use case of "form control reusing" :) The best approach may vary depending on the requirements and goals you want to achieve.
The goal of ControlValueAccessor isn't making the form control reusable (though it is also possible) but rather making a component/directive/DOM element/etc. behave as a form control that can support validation and other Angular form control features. Also, if you look at the source code of angular forms, you will see that the ValueAccessor is used to build a "bridge" between native form controls like input and the model (FormControl) that describes this input but it is not used for sharing purposes.
The pattern from this video works better if you have a static and predictable group of controls that just has to be shared in some other place. Like the use case with billing and delivery address. If we assume that they are static and have the same validators I don't see any problem with encapsulating everything in one component and I don't see any reason to make the host component as the CVA.
If the "magic" embarrasses you, you can drop this part of the pattern and define models explicitly from the parent component, it is also fine :) I also don't like when too much magic happens but if an adequate amount of magic can bring much cleaner code then I am fine with that. For example, when you build your form dynamically, it is very convenient when the component registers the corresponding form control by itself and you don't have to separately manage the form control models and the control component. By the way, Template-Driven forms are doing pretty much the same ;) E.g ngModel creates a FormControl instance and registers them in the parent FormGroup instance created by ngForm directive, so Template-Driven Forms are completely built with this "magic" and many developers like and successfully use them.
Of course, we can have different opinions on it and I respect it. It is absolutely OK to have different points of view and I am very grateful for this interesting discussion :)
@@DecodedFrontendHi Dmytro. I found a solution to the problem of reusable forms on angular university article about custom controls. I dont know is it the best solution (learning angular about 2 months), but the solution helped me
@@DecodedFrontend I've got to agree with @gonzalocorchon6509 and I would like to point out that there are some issues with this approach:
- controlKey when propagated through the codebase will become something the new developpers should learn in order to be able to work. It increases the entry cost of the codebase.
- With this approach you will have not only to add validators and extra inputs to fullfill the features that reactive froms already have, but you have to introduce some error management. In your code, if the parent doesn't have a formGroup, your error will be a null injector instead of the well formatted form of angular, whilest with ControlValueAccesor you'll benefit of angular's error management.
With that being said, I would like to thank you for your content, it's truely amazing, this critic is meant for us all to grow as a community and not discrediting your hard work, I understand a vidéo like this took you hours to make, and I think I can speak for everyone when I say, we truely appreciate your hardwork
Congratulations on this civil discussion!
I came to say the exact same thing and I learned a lot.
Many thanks to both of you
Totally agree with you (see my comment above) and after a few experiments I would also add that (1) ControlValueAccessor gives a bit more flexibility when working with strongly typed form group definitions generated from API types (for example, ToFormGroupType) (2) better way of creating reusable components for arrays in case if you need a bit more code than simple *ngFor (3) ControlValueAccessor-based approach doesn't care about lifecycle hooks in contrast to Dmytro's example where you can't start adding controls in constructor directly, this means that parent component can't start pushing data before OnInit has finished.
BUT ControlValueAccessor comes at a cost of way more complicated code and also has a few other issues like propagating control's validity upstream if you have validators inside ControlValueAccessor-based component.
Fair play. Really solid explanation.
Great content. Much appreciated!
Wow, great solution. Thank you very much!!
Great solution really helpful :)
I have bought the advanced course :D It seems amazing!!!
Thank you 🙏🏻 I excited to hear your feedback in the future 😉
Beautiful solution. Well explained. Well done.
Cool! Thank you!
Thank you so much for this amazing video
You are welcome :)
Great solution! Thanks a lot!
Very nice approach. Thanks a lot😃
Thanks!
Thank you so much for your support 🙏🏻
Thanks for the effort 😊
Great video! Thanks, Dmytro
Why dont just use Control value accessor ?
Thanks you for the video.
Please make a video for creating inline-editing feature for angular material table
Perfect. Thank you so much, my new friend!
This is so good, thanks for the video!
creating a separate component that implements ControlValueAccessor and Validator stuff, just to containt an inner FormGroup and behave as a control also works the same, but this method is so much less painful.
How does this work with typed form though, if a child component is registering the FormControls on the parent FormGroup directive, and it is all configured in the remplate? To me it seems the parent will not know about the existence of those controls, as far as typing goes - it will ofc work in runtime just as the video shows.
Hi Dmytro, How do you overcome the famous "Expression Changed After Checked" console error, in case you use in you main form template expressions like: "form.valid", since you are changing your parent component from a child(when you add the control)??
We can also write in this way:
viewProviders: [
{
provide: ControlContainer,
useExisting: FormGroupDirective,
},
],
Nice! :) but this approach won't be working with a nested form groups ;)
brilliant! you've earned a subscriber 👌👌
❤ Thank you. This is perfect.
thx man, plz create a full web using angular with admin panel
As usual... Superb... Thanks for sharing this...
Interesting idea. What about a template-driven forms?
Does this approach only work with reactive forms?
With template-driven forms, it should also work but for TDF you don't have to register formControl manuals because ngModel doesn't under the hood
Thanks for video. I found an interesting thing here, So if we have some async validators, after each on destroy of our control we will fire updateValueAndValidity under the hood, and make some request. Maybe you know some workaround for this?
Hi, thank you for the video! Really good! But I have a question. How can I reset the complete Form in the Parent Component? Calling reset on the Parent Container set the forms added by the child to null?
Hey! Thanks for your question :) You reset the form the same way as for the regular one. This is because the formControl created by the child component will be eventually registered in the parent formGroup, so it means that if you reset the root formGroup then all child form controls will be reset to null (or initial values)
its dont work in angular 12?
viewProviders: [
{
provide: ControlContainer,
useFactory: () => inject(ControlContainer),
deps: [[new SkipSelf(), ControlContainer]],
},
],
circular Circular dependency in DI detected for ControlContainer
Excellent explanation of this approach! However, if you're going to create the nested form group instance within the child component itself (instead of within the parent component's form group) like this: this.addressFormGroup = new FormGroup(...), wouldn't it be the same thing if you used [formGroup]="addressFormGroup" instead of [formGroupName]="controlKey" in the child component template, since in both cases, the template will be bound to the same nested form group instance? This way, you wouldn't need to use that "rare" feature with viewProviders to make the [formGroupName] work in the template for binding to the correct nested form group instance.
Or is there some extra functionality about FormGroupName directive that FormGroup directive does not have?
Дмитрий, привет! Отличное видео! Помню ты был в очках, сделал коррекцию? Все тоже думаю избавиться от очков, но слышал, что после коррекции нужно не давать нагрузку на глаза, например, не сидеть долго за компьютером.
P.S. не смог пройти по ссылке на курс.
Привет! Спасибо за отзыв о видео 😊
Да, я в апреле сделал коррекцию. Мне в клинике сказали, что лучше пару дней отдохнуть, а потом в обычном режиме можно работать. Там ещё многое зависит от метода. Я делал SMILE и после него на много быстрее восстановление. Я, кажется, отвечал уже в первый день на письма)) В любом случае, всё прошло хорошо, и пока полёт нормальный. Я очень рад!
Какая именно ссылка не работает? Та что в описании или в комментарии? Я проверил, обе вроде работают ок.
Пока можешь попробовать прямой линк - courses.decodedfrontend.io/courses/advanced-angular-forms?coupon=UA-cam_DISCOUNT_2023
We have a parent component with several child components, several of which are further nested, and it's ReactiveForm. Instead of implementing CVA for every child component, or using Inputs/Outputs, we are using FormGroupDirective. So into every child component, that is a part of the form, we inject the FormGroupDirective and add the control to the parent form. Have you seen this approach? I would like to double-check somewhere whether this approach is okay and not breaking good practices :D And what would be a better approach, FormGroupDirective or your in the video?
Thanks for the lesson, it is really cool.
Is it possible to use the same approach without adding a new FormGroup, but add just one control to the parent FormControl?
my question is by adding the formControls inside of the child component, how would you give a type to the formGroup in parent? partial?
Thanks for you question. Unfortunately, strict typing is challenging here and can be added to the disadvantages of this pattern :(
You have amazing skills both coding and teaching although I do not like the reactive way for handling forms. It seems that, when going reactive we're doing job that the framework should do for us.
Great content, best regards from Cuba.
Hi, Dimitro! Continuing the topic of reuse, would you be interested in releasing a video about route reuse strategy?
Another cool video, or should I say: a missing part of Angular docs! I finally understood the resolution decorators Thanks!. Given that the main form model (in this case: AppComponent) is incomplete (the remaining fields are dispersed across other components), how is this going to work with strongly typed forms? Also, if I wanted to author a form AddressGroupComponent that is usable in both ReactiveForms and template driven forms - would I have to author two separate components? I think Angular forms got a bit neglected over time.
thank you sir
subscribed
Thank you so much...
that's awesome, thank you.
Interesting 😊, and that could also be done with FormGroupDirective ?
Yes, but there is a nuance: FormGroupDitective is referencing always the root formGroup. When you have nested form groups then you might get unexpected behavior because controls will be always registered in the root formGroup:)
I undersrand, so it is not advisable to use FormGroupDirective for those cases, or according to your experience what is recommended. Thanks 😊🙌
Hello @DecodedFrontend, your advanced concepts videos are very helpful. Can you please create a tutorial on how to build a Realtime Video chat web app in Angular 14 using webrtc protocol.
another great video, Thanks
why formControlName don't have exportAs ?
Hi Dmytro. Could you give an advice what are cases to use this approach and what are to implement custom form control?
Thanks for your question:) Custom Form Control (aka ControlValueAccessor) is needed when you want to make a regular component behave as a form control and support corresponding features like validation.
The pattern from the video is good for extracting a normal form control into some wrapper for reusing purpose.
Thank you 👍🏼
@DecodedFrontend FormArray example would be much appreciated as well :)
Why is it important to remove control on onDestroy of shared form component?
great content, thanks from nexico
Awesome!!!🚀
Amazing content bro great job … 🎊 🎉
thanks for video 🌺
With that way, Control value accesor is not necessary?
Я недавно чуть не цілий день потратив. Знайшов інше рішення, але це виглядає набагато краще)
Дякую за коментар) яке було ваше рішення, якщо не секрет?)
constructor(private rootFormGroup: FormGroupDirective) {}
ngOnInit(): void {
this.form = this.rootFormGroup.control.get(
this.formGroupName
) as FormGroup
}
Щось таке надибав😅@@DecodedFrontend
Hey 👋🏻 Thanks for sharing. I just curious how does it work with typed forms? 🤔
Fabulous video. Does this work for a stepwise form with angular router?
This solution work with FormArray? If it’s not difficult, show in the next video how this is implemented, thanks
4:51 Option 1 (5 lines): "sooo much boilerplate code"
15:49 Option 2 (13 lines and uses complex rare angular features): "super simple guys"
Thanks for your feedback:) Well, actually, the alternative to option 1 is only the part with viewProviders e.g at 11:55. The rest is an addition which is optional and make sense only for specific use cases like dynamically created forms, etc
How would I set the control values when receiving data from server? How to access the main object from parent form in the child form? @input?
This seems cool, but I'm kinda afraid of using it since it's not the standard way of doing it. Who knows if this API is going to work the same in the next version?
Hi,
Thanks for your comment.
The API used there has existed since the very early version, so I doubt that the risk of the API changes is high :)
Such a great content! 😄
Thank you for your great content. what about if this form group name is a form array ?
Idk why you would use this instead of a proper CVA implementation of an address component. Seems like what you are doing here is a hack built atop of the ControlContainer. Got rid of boiler-plate code in one place, added a ton of it in another. Also have concerns about form validation. How would you validate this control against the parent form, for example the FormControl is marked as required in the parent group, how would you propagate that? What about setting disabled state of the delivery address FormGroup from the parent FormGroup? All this is covered by the ControlValueAccessor and Validator interfaces, and you hook your custom component into the ReactiveForms API directly so you can use [formControl] and [formControlName] directives directly on the component, not inventing custom inputs like [controlKey]. This would be a nightmare to maintain imo.
that git me an error
"The signature '(token: ProviderToken, flags?: InjectFlags): ControlContainer' of 'inject' is deprecated."
need help
What if I need to disable one of the addresses fields from the parent component? Since the address form is being created from the address form component, the parent form (from app component) doesn't know that it exists, right? At least at Typescript level. Or am I missing something?
very nice, Thanks for sharing. But I've one question thou, how about creating a standalone component with sevral different html, how do use change this component html template dynamically?
Thank you for your efforts and sharing knowledge, great content as always and really appreciated
I'm currently working on forms enhancement and reusablility especially the form validation and custom form controls validation messages
And I had a question, after this video they've become two 😂
It is about that is it possible to create a custom directive for example "controlErrorHandler" to use on form controls and it can inject the validation message component like in my case as im using angular material
Is it even applicable that way or there any other better solution, any advice I'd be grateful
The second question came to my mind that you've fixed my problem without even seeing a directive on the controls or inputs and im really curious.
Thanks in advance.
I was looking for the similar stuff and it really helped me. thanks Alot.
also i am trying to write unit test cases for same standalone component and its throwing error on this saying "no provider for ControlContainer". Any idea how to fix that i created one mockClass but not working.
Hi! Thanks you for share this amazing feature. I 've two questions.
I use this approach to create reusable input field (text/email/number and so on), select, radio etc... The reside in separate file and pass in input [controlKey], to the inputFiled component ([formControlName]="controlKey") and the magic appear.
So the question is, what do you think about my solution? It's overkill? There is a simple one solution?
Can I ask you what you think about compare your solution with the FormGroupDirective for create reusable form?