User: i have an angular app with wijmo and i have a dropdwon using that wijmo and form control anf that componenet is child component and data is coming from parent and i want that dropdwon to change selected value in that when value in parent component changes
Assistant: To achieve the functionality of updating a Wijmo dropdown in an Angular child component when the value in the parent component changes, you can use Angular's input bindings and lifecycle hooks. Here's a basic approach you can follow:

### Step 1: Create Parent Component

In your parent component, define a property that holds the selected value for the dropdown. When this property changes, you'll update the input of the child component.

**parent.component.ts**

```typescript
import { Component } from '@angular/core';

@Component({
  selector: 'app-parent',
  templateUrl: './parent.component.html',
})
export class ParentComponent {
  selectedValue: string;

  constructor() {
    this.selectedValue = 'initialValue'; // Initial value for demonstration
  }

  // Method to change value (to simulate changes in the parent)
  changeDropdownValue() {
    this.selectedValue = 'newValue'; // Change this value to see the effect in child
  }
}
```

**parent.component.html**

```html
<div>
  <button (click)="changeDropdownValue()">Change Dropdown Value</button>
  <app-child [selectedValue]="selectedValue"></app-child>
</div>
```

### Step 2: Create Child Component

In the child component, use `@Input` to receive the selected value from the parent component. You will also watch for changes in the input property and update your Wijmo dropdown accordingly.

**child.component.ts**

```typescript
import { Component, Input, OnChanges, SimpleChanges } from '@angular/core';
import * as wjCore from 'wijmo/wijmo';
import * as wjInput from 'wijmo/wijmo.input';

@Component({
  selector: 'app-child',
  templateUrl: './child.component.html',
})
export class ChildComponent implements OnChanges {
  @Input() selectedValue: string;

  dropdown: wjInput.ComboBox;

  ngOnChanges(changes: SimpleChanges) {
    if (changes['selectedValue']) {
      this.updateDropdownSelection();
    }
  }

  ngAfterViewInit() {
    this.dropdown = new wjInput.ComboBox('#my-dropdown', {
      itemsSource: ['initialValue', 'newValue', 'anotherValue'],
      selectedValue: this.selectedValue,
      isEditable: true,
      placeholder: 'Select an option...',
    });
  }

  private updateDropdownSelection() {
    if (this.dropdown) {
      this.dropdown.selectedValue = this.selectedValue; // Update the dropdown selection
    }
  }
}
```

**child.component.html**

```html
<div>
  <input #my-dropdown />
</div>
```

### Step 3: Summary

1. **Parent Component**: Maintains state and changes the selected value. It passes this value to the child component using property binding.
2. **Child Component**: Receives the `selectedValue` as an input and updates the Wijmo ComboBox whenever it changes.

### Notes

- Ensure you have Wijmo and Angular properly set up in your project.
- You may need to adjust the list `itemsSource` to fit the actual values based on your application's needs.
- You may want to add validation and further checks based on your requirements.
- The above example illustrates the full cycle from Angular's input property to the Wijmo dropdown updates, and it lays out a robust pattern for parent-child component interaction in Angular.
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Assistant: