How can I dynamically change the icon of a control center widget?

To dynamically change the icon of a control center widget, you can use the new API introduced in iOS 18. This process involves creating a control, which is a special type of widget, and configuring it to display different symbols based on its state.

Here are the steps to achieve this:

1. Define the Control: Start by defining a control using the same underlying architecture as widgets. Controls can be buttons or toggles, and they use app intents to perform actions.

2. Provide Required Information: Your app needs to provide a symbol, title, tint color, and additional content to the system. This information allows the system to display the control contextually in control center.

3. Customize the Symbol Based on State: You can customize the control to display different symbols based on its state. For example, you can use the isOn argument to the closure to display a different symbol when the control is on or off. This is demonstrated in the session "Extend your app’s controls across the system":

   • When the control is on, display a flowing hourglass symbol to indicate that time is counting down.
   • When the control is off, display a different symbol.

4. Update the Control's Value Text: You can also refine the value text to better match the control's state. For instance, instead of displaying "on" and "off," you can display "running" and "stopped" for a timer control.

For a detailed walkthrough, you can refer to the session Extend your app’s controls across the system (04:11).

Relevant Sessions

• Extend your app’s controls across the system
• Bring your app’s core features to users with App Intents

These sessions provide comprehensive guidance on building and configuring controls, including how to dynamically change their icons based on state.