Events and Callbacks

React to toggle state changes with event-driven programming.

Overview

The SiticoneToggleSwitch provides various events and callbacks to respond to user interactions, state changes, and system updates. Developers can use these events to trigger custom logic, perform validations, or synchronize UI components dynamically.

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1. Available Events and Callbacks 📅

Event	Type	Description
Toggled	EventHandler<ToggledEventArgs>	Fires when the toggle changes state (ON/OFF).
StateChanging	EventHandler<StateChangingEventArgs>	Fires before the state changes, allowing cancellation.
StateChanged	EventHandler<StateChangedEventArgs>	Fires after the state has changed successfully.
SystemThemeChanged	EventHandler<SystemThemeChangedEventArgs>	Fires when the system’s theme changes.

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2. Handling Toggled Event 🔘

Use Case	Trigger Condition
Execute custom actions when the switch is toggled.	Fires every time the switch changes state.

Example

myToggleSwitch.Toggled += (s, e) => 
{
    MessageBox.Show($"Toggle state: {(e.IsOn ? "ON" : "OFF")}");
};

✅ This event ensures UI updates and state-dependent logic execution.

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3. State Changing 🚧

Use Case	Trigger Condition
Prevent toggling under certain conditions.	Fires before the toggle state changes.

Example

myToggleSwitch.StateChanging += (s, e) =>
{
    if (e.NewState == false) // Prevent turning OFF
    {
        e.Cancel = true;
        MessageBox.Show("This switch cannot be turned OFF!");
    }
};

✅ This event allows validation before state changes.

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4. State Changed 🔄

Use Case	Trigger Condition
Execute logic after the toggle switch state has changed.	Fires only after the state update is completed.

Example

myToggleSwitch.StateChanged += (s, e) =>
{
    Console.WriteLine($"Switch is now {(e.NewState ? "ON" : "OFF")}");
};

✅ Helps in tracking final state changes and performing post-change actions.

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5. System Theme 🎨

Use Case	Trigger Condition
Adapt the toggle switch appearance to match OS theme changes.	Fires when Windows theme (Light/Dark) updates.

Example

myToggleSwitch.SystemThemeChanged += (s, e) =>
{
    MessageBox.Show($"System theme changed to: {e.NewTheme}");
};

✅ Ensures the toggle switch remains visually consistent with system themes.

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6. Using These Events ✅

Event	Use Case
Toggled	When executing custom actions after a toggle state change.
StateChanging	When validating and preventing state changes dynamically.
StateChanged	When performing follow-up actions after a successful state change.
SystemThemeChanged	When adapting UI to match system-wide themes.

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7. Common Pitfalls & Design Considerations 🛑

Pitfall	Cause	Solution
Event not firing	Handler not attached	Ensure the event is properly subscribed.
StateChanging doesn’t prevent toggling	e.Cancel = true; not set	Explicitly set the Cancel property to true.
Laggy UI updates	Heavy logic in event handlers	Move complex operations to background tasks.

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8. Points Learned 🎯

Point	Description
Events provide better control over state changes.	Enables dynamic UI behaviors and custom logic execution.
Preventing unwanted toggles avoids unexpected user actions.	StateChanging ensures proper validation before state updates.
Post-change actions can be automated.	StateChanged helps synchronize UI and backend states.

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9. Review Checklist ✔️

Item	Check
Is the Toggled event firing as expected?	✅
Does StateChanging properly prevent invalid toggles?	✅
Are UI updates synchronized with SystemThemeChanged?	✅

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10. Key Takeaways

Key Takeaway	Description
Events allow real-time response to user interactions.	Enables immediate reactions to toggle changes.
State validation prevents incorrect behavior.	Avoids invalid or undesired state transitions.
Proper event usage improves UI adaptability.	Ensures consistent user experience across different themes.

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11. Summary 📌

11.1 Feature Summary

Event	Trigger Condition	Usage
Toggled	Fires when the toggle state changes.	Execute actions when ON/OFF.
StateChanging	Fires before a state change occurs.	Validate and prevent changes when needed.
StateChanged	Fires after a state change is completed.	Perform follow-up tasks after toggle updates.
SystemThemeChanged	Fires when the OS theme changes.	Adapt toggle appearance dynamically.

11.2 Key Benefits

Benefit	Description
Allows developers to handle toggle events dynamically.	Supports real-time state tracking.
Prevents unwanted state changes when necessary.	StateChanging provides full control over transitions.
Ensures UI consistency with OS themes.	Matches system-wide dark/light mode dynamically.