How Can You Create an Expand Collapse Panel in Angular Without Using Material UI?

AvatarByLeonard Waldrup Stack Overflow Queries

### Introduction

In the world of web development, creating a seamless user experience is paramount, and one effective way to achieve this is through the use of expand and collapse panels. These dynamic components allow users to interact with content in a more organized manner, making it easier to navigate through large datasets or complex information. While many developers turn to Material UI for ready-made solutions, there’s a wealth of opportunities to create custom expand/collapse panels in Angular without relying on external libraries. This approach not only enhances your coding skills but also provides greater flexibility in design and functionality.

Building an expand/collapse panel in Angular opens up a realm of possibilities for developers looking to customize their applications. By leveraging Angular’s powerful directives and data binding capabilities, you can create panels that respond intuitively to user interactions. This not only improves the aesthetic appeal of your application but also optimizes performance by loading content only when necessary. Whether you’re displaying FAQs, product details, or any other type of information, understanding how to implement these panels effectively can significantly enhance user engagement.

In this article, we will explore the fundamental concepts behind creating an expand/collapse panel in Angular without the use of Material UI. We’ll delve into the core principles of Angular’s component architecture, discuss best practices for managing state, and

Creating Expand/Collapse Functionality

To implement an expand/collapse panel in Angular without using Material UI, you can leverage Angular’s built-in directives and services. This approach involves using structural directives like `*ngIf` and property binding to manage the visibility of the content within the panel.

The fundamental concept is to toggle a boolean variable that determines whether the panel content is displayed or hidden. Below is a basic example of how to create an expandable panel:

{{ title }}

{{ isOpen ? ‘-‘ : ‘+’ }}

In your component, you would define the `togglePanel()` method and the `isOpen` boolean variable:

typescript
export class ExpandCollapsePanelComponent {
isOpen = ;
@Input() title: string;

togglePanel() {
this.isOpen = !this.isOpen;
}
}

Styling the Panel

Aesthetic considerations are crucial for user experience. You can use CSS to style the panel effectively. Below is a simple CSS snippet for the panel:

css
.panel {
border: 1px solid #ccc;
border-radius: 4px;
margin-bottom: 10px;
}

.panel-header {
background-color: #f1f1f1;
padding: 10px;
cursor: pointer;
}

.panel-content {
padding: 10px;
background-color: #ffffff;
}

This will ensure your panel has a clear separation between the header and content, enhancing usability.

Using Angular Directives

Angular directives are instrumental in creating reusable components. In this case, you can create a directive for the expandable panel to encapsulate the functionality. Here’s how you can define a simple directive:

typescript
import { Directive, Input, TemplateRef, ViewContainerRef } from ‘@angular/core’;

@Directive({
selector: ‘[appExpandCollapse]’
})
export class ExpandCollapseDirective {
@Input() set appExpandCollapse(condition: boolean) {
if (condition) {
this.viewContainer.createEmbeddedView(this.templateRef);
} else {
this.viewContainer.clear();
}
}

constructor(private templateRef: TemplateRef, private viewContainer: ViewContainerRef) {}
}

You can then use this directive in your panel component like this:

Example Usage

To illustrate how the expandable panel can be employed in an application, you can create a parent component that utilizes the `ExpandCollapsePanelComponent`. Below is an example of how to integrate this component into your application:


This is the content of the panel that will be displayed upon expansion.

This setup allows you to create multiple panels seamlessly within your application.

Advantages of Custom Implementation

Creating an expandable panel without Material UI offers several benefits:

  • Customization: You have full control over the design and behavior.
  • Lightweight: Avoids the overhead of additional libraries, resulting in a lighter application.
  • Simplicity: Easier to understand and maintain for small projects.
Feature Custom Implementation Material UI
Customization High Moderate
Performance Optimized Dependent on library
Complexity Low Higher due to dependencies

Creating an Expand/Collapse Panel

To create an expand/collapse panel in Angular without relying on Material UI, you can utilize Angular’s built-in directives alongside CSS for styling and transitions. Below are the steps to implement this functionality effectively.

Setup Angular Component

First, you need to create a component that will serve as your expand/collapse panel. Below is an example of how to set up the component.

typescript
import { Component } from ‘@angular/core’;

@Component({
selector: ‘app-expand-collapse-panel’,
templateUrl: ‘./expand-collapse-panel.component.html’,
styleUrls: [‘./expand-collapse-panel.component.css’]
})
export class ExpandCollapsePanelComponent {
isExpanded = ;

togglePanel() {
this.isExpanded = !this.isExpanded;
}
}

HTML Template

The HTML template will include the button for toggling the panel as well as the content that will expand or collapse. Here’s a simple example:

This is the content of the panel.

Styling the Panel

CSS is essential for making the panel visually appealing and to handle the transitions. Here’s an example of the CSS you might use:

css
.panel {
border: 1px solid #ccc;
border-radius: 4px;
margin: 10px 0;
}

button {
background-color: #007bff;
color: white;
border: none;
padding: 10px;
cursor: pointer;
}

.panel-content {
max-height: 0;
overflow: hidden;
transition: max-height 0.3s ease-out;
}

.panel-content.expanded {
max-height: 100px; /* Adjust as needed */
}

Using Angular Directives

In the template, the `ngClass` directive conditionally adds the ‘expanded’ class based on the `isExpanded` variable, allowing for smooth transitions. You can further enhance the panel’s functionality by adding animations using Angular’s animation library if desired.

Example of Using the Panel

You can now use the `ExpandCollapsePanelComponent` in your parent component or module as follows:

Handling Accessibility

For better accessibility, consider the following:

  • Use ARIA attributes to indicate the panel’s state:
  • Add `aria-expanded` to the button.
  • Ensure that keyboard navigation is supported.

Example modification of the button:

Implementing an expand/collapse panel in Angular without Material UI is a straightforward process that allows for flexibility and customization. By leveraging Angular’s capabilities and CSS, you can create an efficient and user-friendly interface component that meets your project’s needs.

Expert Insights on Implementing Expand Collapse Panels in Angular Without Material UI

Emily Chen (Frontend Developer, Tech Innovations Inc.). “Implementing expand collapse panels in Angular without Material UI can be achieved through custom directives. This approach allows for greater flexibility and control over the styling and behavior of the components, ensuring a seamless integration with existing UI frameworks.”

Michael Torres (Senior Angular Consultant, CodeCraft Solutions). “Using Angular’s built-in structural directives like *ngIf and *ngFor, developers can create efficient expand collapse panels that enhance user experience while maintaining performance. This method avoids the overhead of additional libraries and keeps the application lightweight.”

Sarah Patel (UI/UX Designer, Creative Tech Studio). “A key aspect of designing expand collapse panels in Angular is ensuring accessibility. By utilizing ARIA attributes and keyboard navigation, developers can create panels that are not only functional but also inclusive for all users, regardless of their abilities.”

Frequently Asked Questions (FAQs)

What is an expand-collapse panel in Angular?
An expand-collapse panel in Angular is a user interface component that allows users to toggle the visibility of content. When expanded, the panel displays additional information; when collapsed, it hides that information, enhancing the user experience by saving space.

How can I create an expand-collapse panel in Angular without Material UI?
You can create an expand-collapse panel by using Angular’s built-in directives such as `*ngIf` or `*ngFor` along with a button or clickable header to toggle a boolean variable that controls the visibility of the content.

What are the key components of an expand-collapse panel?
The key components include a header or title that the user can click to toggle the panel, a content area that displays the information, and a mechanism (like a boolean variable) to manage the open and closed states.

Can I style the expand-collapse panel using CSS?
Yes, you can style the expand-collapse panel using CSS. You can customize the appearance of the header, content, and transition effects by applying appropriate styles to the relevant classes or elements.

Are there any libraries available for creating expand-collapse panels in Angular?
Yes, there are several libraries available, such as ngx-bootstrap or ng-bootstrap, which provide pre-built components, including expand-collapse panels, that can be easily integrated into your Angular application without using Material UI.

How can I manage multiple expand-collapse panels in a single component?
You can manage multiple panels by maintaining an array of boolean values, where each value corresponds to the open/closed state of a panel. Use an index to toggle the specific panel’s state based on user interaction.
implementing an expand/collapse panel in Angular without relying on Material UI can be achieved through various methods that leverage Angular’s built-in features. By utilizing structural directives such as *ngIf and *ngFor, developers can create dynamic components that respond to user interactions, allowing for a seamless experience. Custom styling and animations can further enhance the user interface, providing a polished look that aligns with specific design requirements.

Key takeaways include the importance of understanding Angular’s component architecture and how to effectively manage state within components. By using services or component properties to track the expanded or collapsed state, developers can ensure that their panels behave predictably. Additionally, the use of CSS for transitions and animations can significantly improve user engagement, making the expand/collapse functionality not only functional but also visually appealing.

Overall, creating an expand/collapse panel in Angular without Material UI is a straightforward process that allows for greater customization and flexibility. By focusing on Angular’s core features and best practices, developers can build intuitive interfaces that enhance user experience while maintaining control over the design and functionality of their applications.

Author Profile

Avatar
Leonard Waldrup
I’m Leonard a developer by trade, a problem solver by nature, and the person behind every line and post on Freak Learn.

I didn’t start out in tech with a clear path. Like many self taught developers, I pieced together my skills from late-night sessions, half documented errors, and an internet full of conflicting advice. What stuck with me wasn’t just the code it was how hard it was to find clear, grounded explanations for everyday problems. That’s the gap I set out to close.

Freak Learn is where I unpack the kind of problems most of us Google at 2 a.m. not just the “how,” but the “why.” Whether it's container errors, OS quirks, broken queries, or code that makes no sense until it suddenly does I try to explain it like a real person would, without the jargon or ego.