Set a value for the getter

Question

Set a value for the getter

In the component, I have a getter that looks like this:

     public get canSave(): boolean {
    const isValid = this.rows.every(r => r.phoneControl.valid);

    if (!isValid) {
      return false;
    }

    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    return changes.phones.changed || changes.emergencyPhone.changed;
  }

Now, in the onSubmitClick method, I need to update the value of this getter. Here is what I attempted:

    public onSubmitClick(): void {
    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    this.canSave = false;

    this.params
      .onSubmit(changes)
      .pipe(take(1))
      .subscribe(() => {
        this.close(true).then();
      });
  }

However, an error occurred:

Cannot assign to 'canSave' because it is a read-only property.

So, how can I update the value of canSave in the onSubmitClick method? Below is the complete code for the component:

    export class ManagePhonesPopup extends DialogBaseComponent<Params, boolean> implements OnInit {
  // Component properties and methods here

javascript angular typescript

Answer 1

Answer №1

It seems like you are in search of a way to manipulate the return value of canSave.

One approach is to introduce two new private fields to your class:

  private _forcingCanSave = false;     // indicates if we are forcing the value
  private _forcedCanSaveValue = false; // the value to be returned when forced

You can then adjust your existing logic as follows:

  public get canSave(): boolean {
    if (this._forcingCanSave) return this._forcedCanSaveValue; // return the forced value if in "forcing mode"

    const isValid = this.rows.every(r => r.phoneControl.valid);

    if (!isValid) {
      return false;
    }

    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    return changes.phones.changed || changes.emergencyPhone.changed;
  }

To enable the "forcing mode," you can create a method like this:

  private forceCanSave(state: boolean) {
    this._forcingCanSave = true;
    this._forcedCanSaveValue = state;
  }

This enables overriding the value in canSave. You can use it in scenarios like this:

  public onSubmitClick(): void {
    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    this.forceCanSave(false); // force canSave to return false

    this.params
      .onSubmit(changes)
      .pipe(take(1))
      .subscribe(() => {
        this.close(true).then();
      });
  }

Furthermore, consider adding a method to disable the "forcing mode," such as stopForcingCanSave(), which sets this._forcingCanSave = false;. This will be useful for ending the forced behavior when needed.

Answer 2

It seems like you are in search of a way to manipulate the return value of canSave.

One approach is to introduce two new private fields to your class:

  private _forcingCanSave = false;     // indicates if we are forcing the value
  private _forcedCanSaveValue = false; // the value to be returned when forced

You can then adjust your existing logic as follows:

  public get canSave(): boolean {
    if (this._forcingCanSave) return this._forcedCanSaveValue; // return the forced value if in "forcing mode"

    const isValid = this.rows.every(r => r.phoneControl.valid);

    if (!isValid) {
      return false;
    }

    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    return changes.phones.changed || changes.emergencyPhone.changed;
  }

To enable the "forcing mode," you can create a method like this:

  private forceCanSave(state: boolean) {
    this._forcingCanSave = true;
    this._forcedCanSaveValue = state;
  }

This enables overriding the value in canSave. You can use it in scenarios like this:

  public onSubmitClick(): void {
    const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
    this.forceCanSave(false); // force canSave to return false

    this.params
      .onSubmit(changes)
      .pipe(take(1))
      .subscribe(() => {
        this.close(true).then();
      });
  }

Furthermore, consider adding a method to disable the "forcing mode," such as stopForcingCanSave(), which sets this._forcingCanSave = false;. This will be useful for ending the forced behavior when needed.

Answer 3

Answer №2

Implement a private property named _canSave and ensure it is updated correctly within the onSubmitClick function.

export class ManagePhonesPopup extends DialogBaseComponent<Params, boolean> implements OnInit {
      public override params!: Params;
      public rows: IPhoneRow[] = [];
    
      private _canSave: boolean = false; // Private property to track save status
    
      public get canSave(): boolean {
        const isValid = this.rows.every(r => r.phoneControl.valid);
    if (this._canSave === false) {
      return false;
     }
        if (!isValid) {
          return false;
        }
    
        const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
        return this._canSave || changes.phones.changed || changes.emergencyPhone.changed;
      }
    
      constructor(
        dialog: DialogRef,
        confirmDialog: ConfirmDialogService,
        private readonly managePhonesPopupService: ManagePhonesPopupService,
      ) {
        super(dialog, confirmDialog);
      }
    
      public ngOnInit(): void {
        this.initRows(this.params.phones, this params.emergencyPhone);
      }
    
      public onAddClick(): void {
        const newRow = this.managePhonesPopupService.createRowControls('', false);
        this.rows.push(newRow);
      }
    
      public onDeleteClick(row: IPhoneRow): void {
        this.rows = this.rows.filter(r => r != row);
      }
    
      public onCloseClick(): void {
        this.close().then();
      }
    
      public onSubmitClick(): void {
        const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
        this._canSave = false; // Update the private property
    
        this.params
          .onSubmit(changes)
          .pipe(take(1))
          .subscribe(() => {
            this.close(true).then();
          });
      }
    
      private initRows(phones: IEmployeeCellphone[], emergencyPhone?: string): void {
        const rows: IPhoneRow[] = phones.map(p => this.managePhonesPopupService.cellphoneToRowControls(p));
    
        if (!!emergencyPhone) {
          rows.push(this.managePhonesPopupService.emergencyPhoneToRowControls(emergencyPhone));
        }
    
        this.rows = rows;
      }
    }

Answer 4

Implement a private property named _canSave and ensure it is updated correctly within the onSubmitClick function.

export class ManagePhonesPopup extends DialogBaseComponent<Params, boolean> implements OnInit {
      public override params!: Params;
      public rows: IPhoneRow[] = [];
    
      private _canSave: boolean = false; // Private property to track save status
    
      public get canSave(): boolean {
        const isValid = this.rows.every(r => r.phoneControl.valid);
    if (this._canSave === false) {
      return false;
     }
        if (!isValid) {
          return false;
        }
    
        const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
        return this._canSave || changes.phones.changed || changes.emergencyPhone.changed;
      }
    
      constructor(
        dialog: DialogRef,
        confirmDialog: ConfirmDialogService,
        private readonly managePhonesPopupService: ManagePhonesPopupService,
      ) {
        super(dialog, confirmDialog);
      }
    
      public ngOnInit(): void {
        this.initRows(this.params.phones, this params.emergencyPhone);
      }
    
      public onAddClick(): void {
        const newRow = this.managePhonesPopupService.createRowControls('', false);
        this.rows.push(newRow);
      }
    
      public onDeleteClick(row: IPhoneRow): void {
        this.rows = this.rows.filter(r => r != row);
      }
    
      public onCloseClick(): void {
        this.close().then();
      }
    
      public onSubmitClick(): void {
        const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
        this._canSave = false; // Update the private property
    
        this.params
          .onSubmit(changes)
          .pipe(take(1))
          .subscribe(() => {
            this.close(true).then();
          });
      }
    
      private initRows(phones: IEmployeeCellphone[], emergencyPhone?: string): void {
        const rows: IPhoneRow[] = phones.map(p => this.managePhonesPopupService.cellphoneToRowControls(p));
    
        if (!!emergencyPhone) {
          rows.push(this.managePhonesPopupService.emergencyPhoneToRowControls(emergencyPhone));
        }
    
        this.rows = rows;
      }
    }

Answer 5

Answer №3

Within your code, the canSave function serves as a getter, meaning it is a read-only property. However, you are attempting to assign a value to it, which violates this constraint.

Instead of directly assigning a value to canSave, the recommended approach is to update the properties that influence the behavior of canSave. In this scenario, canSave relies on this.rows and this.params. Therefore, these properties should be modified within the onSubmitClick method.

Below is an example:

public onSubmitClick(): void {
 const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
 
 // Update the rows or params here
 // For instance, if you wish to mark all rows as invalid, you can accomplish this by:
 this.rows = this.rows.map(r => ({ ...r, phoneControl: { ...r.phoneControl, valid: false } }));

 this.params
   .onSubmit(changes)
   .pipe(take(1))
   .subscribe(() => {
     this.close(true).then();
   });
}

By updating this.rows to designate all rows as invalid, you will need to customize this section based on your specific requirements.

*The crucial step is to adjust the properties that impact canSave, rather than modifying canSave itself.

Answer 6

Within your code, the canSave function serves as a getter, meaning it is a read-only property. However, you are attempting to assign a value to it, which violates this constraint.

Instead of directly assigning a value to canSave, the recommended approach is to update the properties that influence the behavior of canSave. In this scenario, canSave relies on this.rows and this.params. Therefore, these properties should be modified within the onSubmitClick method.

Below is an example:

public onSubmitClick(): void {
 const changes = this.managePhonesPopupService.getChanges(this.rows, this.params);
 
 // Update the rows or params here
 // For instance, if you wish to mark all rows as invalid, you can accomplish this by:
 this.rows = this.rows.map(r => ({ ...r, phoneControl: { ...r.phoneControl, valid: false } }));

 this.params
   .onSubmit(changes)
   .pipe(take(1))
   .subscribe(() => {
     this.close(true).then();
   });
}

By updating this.rows to designate all rows as invalid, you will need to customize this section based on your specific requirements.

*The crucial step is to adjust the properties that impact canSave, rather than modifying canSave itself.

Set a value for the getter

Answer №1

Answer №2

Answer №3

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