Theme & Accent Events

A feature that enables developers to subscribe to system theme and accent color changes to dynamically update their application's UI.

Overview

This feature exposes the events ThemeChanged, AccentColorChanged, and HighContrastChanged from the SiticoneThemeTracker component, allowing the application to react when the system's theme or accent color changes. By subscribing to these events, developers can implement custom logic to update controls, refresh layouts, or trigger other UI adjustments as needed.

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Key Points

Aspect	Details
Events	ThemeChanged (provides updated SystemTheme), AccentColorChanged (provides updated Color), HighContrastChanged (indicates high contrast mode changes)
Data Provided	ThemeChangedEventArgs, AccentColorChangedEventArgs, HighContrastChangedEventArgs
Usage	Use events to execute custom UI update logic when the system theme or accent color changes
Integration	Events can be easily integrated by subscribing within the form or control initialization code

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Best Practices

Practice	Description
Always Unsubscribe	Unsubscribe from events during disposal or form closure to avoid memory leaks or unexpected behavior
Centralize UI Updates	Implement a centralized method for handling UI refreshes in response to these events to ensure consistency across the application
Validate Event Data	Always validate the event arguments to ensure correct handling of the theme or accent changes (e.g., checking for valid colors or theme states)
Use Event Handlers for Logging	Use event handlers to log theme or accent changes for debugging or analytics purposes

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Common Pitfalls

Pitfall	Explanation
Not Unsubscribing	Failing to remove event handlers on form close may lead to memory leaks or null reference exceptions when events are triggered post-disposal.
Overcomplicating the Event Logic	Embedding too much logic in the event handler can lead to performance issues; it is better to call lightweight methods that update the UI accordingly.
Ignoring High Contrast Mode	Overlooking the HighContrastChanged event might result in UI elements that are not accessible for users with high contrast requirements.

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Usage Scenarios

Scenario	Description
Dynamic Theme Adaptation	Subscribe to ThemeChanged to automatically refresh the UI when the user switches between dark and light modes.
Accent Color Integration	Use the AccentColorChanged event to update the styling of interactive elements (e.g., buttons, links) to match the new system accent color.
Accessibility Enhancement	Handle the HighContrastChanged event to adjust UI elements for improved accessibility, such as increasing font sizes or changing contrast ratios.

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Real Life Usage Scenarios

Scenario	Description
Responsive UI for Enterprise Apps	In an enterprise application where branding and accessibility are crucial, events can trigger a re-rendering of dashboards or forms when system themes change.
Customizable User Interfaces	Applications that allow user-customizable interfaces can listen for these events to automatically adjust their color schemes and layout configurations dynamically.
Analytics & Debugging	Log events such as ThemeChanged or AccentColorChanged to track user behavior or debug issues related to UI responsiveness across different system settings.

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Troubleshooting Tips

Issue	Suggested Resolution
Event Not Firing	Verify that the component is properly initialized and that the operating system settings are correctly triggering the events (e.g., changing themes in Windows settings).
Memory Leaks	Ensure that all event subscriptions are removed during the disposal of the form or component to prevent lingering references.
Incorrect Event Data	Debug the event arguments (ThemeChangedEventArgs, AccentColorChangedEventArgs, HighContrastChangedEventArgs) to confirm that they contain the expected values.

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Integration Example

Below is an example demonstrating how to integrate and use the Theme & Accent Events feature in a .NET WinForms application.

using System;
using System.Drawing;
using System.Windows.Forms;
using SiticoneNetFrameworkUI;

namespace ThemeEventsDemo
{
    public partial class MainForm : Form
    {
        private SiticoneThemeTracker themeTracker;

        public MainForm()
        {
            InitializeComponent();
            InitializeThemeEvents();
        }

        private void InitializeThemeEvents()
        {
            // Instantiate the theme tracker
            themeTracker = new SiticoneThemeTracker();

            // Subscribe to theme change events
            themeTracker.ThemeChanged += ThemeTracker_ThemeChanged;
            themeTracker.AccentColorChanged += ThemeTracker_AccentColorChanged;
            themeTracker.HighContrastChanged += ThemeTracker_HighContrastChanged;

            // Optionally display initial theme and accent color
            UpdateUIBasedOnTheme();
        }

        private void ThemeTracker_ThemeChanged(object sender, ThemeChangedEventArgs e)
        {
            // Update the UI when the theme changes
            Console.WriteLine("Theme changed to: " + e.CurrentTheme);
            UpdateUIBasedOnTheme();
        }

        private void ThemeTracker_AccentColorChanged(object sender, AccentColorChangedEventArgs e)
        {
            // Update the UI with the new accent color
            Console.WriteLine("Accent color changed to: " + e.AccentColor);
            UpdateUIBasedOnTheme();
        }

        private void ThemeTracker_HighContrastChanged(object sender, HighContrastChangedEventArgs e)
        {
            // Adjust the UI for high contrast mode
            Console.WriteLine("High contrast mode is " + (e.IsHighContrast ? "enabled" : "disabled"));
            UpdateUIBasedOnTheme();
        }

        private void UpdateUIBasedOnTheme()
        {
            // Use the current theme and accent color to update UI elements
            this.BackColor = themeTracker.CurrentTheme == SystemTheme.Dark ? Color.FromArgb(32, 32, 32) : SystemColors.Window;
            labelThemeInfo.Text = "Theme: " + themeTracker.CurrentTheme;
            labelAccentInfo.Text = "Accent: " + themeTracker.AccentColor;
        }

        protected override void OnFormClosed(FormClosedEventArgs e)
        {
            // Unsubscribe from events and dispose of the theme tracker
            themeTracker.ThemeChanged -= ThemeTracker_ThemeChanged;
            themeTracker.AccentColorChanged -= ThemeTracker_AccentColorChanged;
            themeTracker.HighContrastChanged -= ThemeTracker_HighContrastChanged;
            themeTracker.Dispose();
            base.OnFormClosed(e);
        }
    }
}

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Code Sample Explanation

Section	Explanation
Initialization	The SiticoneThemeTracker is instantiated and event handlers for ThemeChanged, AccentColorChanged, and HighContrastChanged are attached.
Event Handling	Each event handler logs changes and updates the UI by calling UpdateUIBasedOnTheme, ensuring that the user interface reflects the current system settings.
UI Update	The method UpdateUIBasedOnTheme adjusts the form's background and updates labels based on the current theme and accent color.
Disposal	Event handlers are unsubscribed and the theme tracker is disposed of in the OnFormClosed method to prevent resource leaks and ensure proper cleanup.

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Review

Aspect	Review Comments
Ease of Integration	Event-based integration allows for seamless updates to the UI without polling for changes.
Responsiveness	Quick reaction to system theme or accent color changes enhances the user experience by providing an adaptive UI.
Resource Management	Proper subscription and unsubscription practices are critical to avoid memory leaks, as demonstrated in the sample integration.

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Summary

Summary Aspect	Summary Details
Functionality	Provides event notifications for changes in system theme, accent color, and high contrast mode, enabling dynamic and responsive UI updates.
Developer Benefits	Simplifies the process of reacting to system changes with minimal code overhead and clear event-driven patterns.
Integration Ease	Straightforward integration through event subscriptions and lightweight event handlers that can be easily extended to include custom UI logic.

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Additional Useful Sections

Integration Checklist

Checklist Item	Status/Notes
Component Instantiation	Ensure SiticoneThemeTracker is instantiated at the start of the form or application.
Event Subscriptions	Subscribe to ThemeChanged, AccentColorChanged, and HighContrastChanged events appropriately.
Centralized UI Update Method	Create a dedicated method (e.g., UpdateUIBasedOnTheme) to handle UI refresh logic uniformly.
Unsubscribe on Disposal	Unsubscribe from all events in the OnFormClosed or Dispose method to prevent memory leaks.
Logging and Debugging	Optionally add logging within event handlers to monitor system changes for debugging purposes.

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FAQ

Question	Answer
How do I subscribe to theme changes?	Instantiate the SiticoneThemeTracker and subscribe to its ThemeChanged event using a suitable event handler.
What should I do if my UI does not update?	Ensure that your event handlers are correctly attached, the UI update method is being called, and that no custom code overrides the event-driven changes.
How can I handle high contrast mode changes?	Subscribe to the HighContrastChanged event and adjust your UI elements (e.g., font size, control borders) to be more accessible based on the event data.
Is it necessary to unsubscribe from the events?	Yes, unsubscribing from events when the form or component is disposed of is important to prevent memory leaks and unintended behavior after disposal.

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This comprehensive documentation for the Theme & Accent Events feature provides detailed guidance, examples, and best practices to help developers integrate and utilize the event-driven capabilities of the SiticoneThemeTracker component in their .NET WinForms applications.