The Ionic error message indicates that the variable v.context.$implicit has not been

My code is giving me an error message that says: "v.context.$implicit is undefined."

The issue seems to be inconsistent - it sometimes throws an error and other times it doesn't. Can someone please explain why this is happening?

This is my HTML code snippet:

<ng-container *ngFor="let time of item.timeInfo | keys" >
    <ion-row *ngIf="time == thisDay"> 
      <ion-col col-3 no-padding>
        <ng-container *ngIf="checkTime(); else closeButton">
          <button small ion-button block color="secondary" outline> OPEN </button>
        </ng-container>
        <ng-template #closeButton>
          <button small ion-button block color="danger" outline>Close </button>
        </ng-template>
      </ion-col>
      <ion-col col-9 >
        {{ item.timeInfo[thisDay].open }} - {{ item.timeInfo[thisDay].close }}
      </ion-col>
    </ion-row>
  </ng-container>

This is the JSON code for 'item':

"item":{
   "timeInfo": {
            "Sat": {
                "open": "11:00",
                "close": "21:00"
            },
            "Sun": {
                "open": "9:00",
                "close": "21:30"
            },
            "Mon": {
                "open": "11:00",
                "close": "22:30"
            },
            "Tue": {
                "open": "12:00",
                "close": "22:00"
            },
            "Web": {
                "open": "12:00",
                "close": "22:30"
            },
            "Thu": {
                "open": "9:30",
                "close": "22:30"
            },
            "Fri": {
                "open": "12:30",
                "close": "22:00"
            }
        },
 };

And here are the details of my current setup:

@ionic/cli-utils  : 1.15.2
ionic (Ionic CLI) : 3.15.2

local packages:
@ionic/app-scripts : 3.0.0
Ionic Framework    : ionic-angular 3.7.1

System:
Node : v6.11.2
npm  : 5.4.2
OS   : Windows 8.1

Misc:
backend : pro

Any help on resolving this issue would be greatly appreciated. Thank you very much!

jsontypescriptionic-frameworkionic2implicit

Answer №1

I stumbled upon a similar issue before when I attempted to add new data into an array using the incorrect method. Instead of using result[i] = data[i], the correct approach is to use result.push(data[i]). Your TS code would be helpful for me to provide more specific assistance. Hopefully this solution resolves your problem!

Answer №2

Usually, when referencing context.$implicit in the template, it is pointing to a variable that has been created with a "let" statement (such as "let time of item.info").

The error message saying "is undefined" is a common Javascript error that occurs when trying to use an undefined value as if it were an object.

In your particular situation, this error likely occurs when the variable thisDay does not match any of the keys in the timeinfo object. Reviewing the specific line of the error can help identify where the problem lies in the HTML code.

Answer №3

Having encountered a similar issue, I found the solution by making a simple adjustment: changing "was" to "became."

<button *ngIf="!readOnly && file.length">Remove</button> // error
<button *ngIf="!readOnly && (file && file.length)">Remove</button> //no error

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