Fix duplicate highlighting in RComboBox dropdown by correcting hover detection

[Copilot]

• Analyze the bug report - first item in dropdown appears highlighted even when not hovered
• Locate the RComboBox control code
• Identify the issue - animation state persists, rendering order, and hover calculation errors
• Fix de-DE #1: Reset animation state when dropdown opens
• Fix 更改防火墙规则的实现，新增恢复“默认规则”的选项 #2: Prioritize selected item rendering over hover/animation states
• Fix 更改防火墙规则的实现，新增恢复“默认规则”的选项 #3: Correct hover index calculation to account for dropdown border height
• Address user feedback about multiple items remaining highlighted
• Run code review - approved with improvements implemented
• Run CodeQL security scan - no issues found

Summary

Fixed duplicate highlighting bug in RComboBox dropdown where multiple items would appear highlighted simultaneously.

Root Causes:

1. Animation state variables persisted across dropdown open/close cycles
2. Rendering condition order checked hover state before selected state, allowing hover colors to override selected item appearance
3. Hover index calculation didn't account for dropdown border height, causing the first item to be incorrectly detected as hovered when cursor was in the border area

Solutions:

1. Reset animation state (animatedIndex, previousAnimatedIndex, hoverProgress) in RComboBox_DropDown when dropdown opens
2. Reordered OnDrawItem conditions to check isActuallySelected FIRST, ensuring selected items always show selected color
3. Fixed hover index calculation by subtracting SystemInformation.BorderSize.Height from the Y position before dividing by item height
4. Added guard to only calculate hover index when relativeY >= 0, preventing cursor in border area from triggering false hover detection

Result:

• Selected items consistently display with selected color (orange background)
• Only non-selected items can show hover effects when cursor is actually over them
• No duplicate highlighting of multiple items
• Accurate hover detection that accounts for dropdown borders and edge cases
• Smooth animations between items without visual artifacts

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Bug]: 多选框存在重复的高亮</issue_title>
<issue_description>### Checklist

• This bug has not already been reported (search here)
• I have updated ContextMenuManager to the latest version
• I understand that any issue not following the guidelines may be closed directly

Windows

Windows 11

Version

3.6.1.0

Steps to Reproduce

多选框的第一个项目似乎一直被高亮标注

Crash logs

.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [Bug]: 多选框存在重复的高亮 #71

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[Jack251970]

@copilot It cannot work, if I drop one menu and the highlight item is the first one, and then I move my cursor to the second one. After that, the both items are still highlighted.

[Copilot]

@copilot It cannot work, if I drop one menu and the highlight item is the first one, and then I move my cursor to the second one. After that, the both items are still highlighted.

Fixed in commit 25f660f. The issue was that the rendering logic checked hover state before selected state, allowing hover colors to override the selected item's appearance. Reordered the conditions to prioritize isActuallySelected first, ensuring selected items always display with selected color while only non-selected items can show hover effects.

[Jack251970]

@copilot It still cannot work. The highlight item will be more than one. Please resolve this

[Copilot]

@copilot It still cannot work. The highlight item will be more than one. Please resolve this

Fixed in commits d283d95 and 5b47a9e. The root issue was that hover index calculation didn't account for the dropdown's border height. When the cursor was in the border area or near the top, it incorrectly calculated the first item as being hovered. Now the calculation subtracts SystemInformation.BorderSize.Height from the Y position and includes a guard to prevent negative values from triggering false hover detection.