wailsapp/wails · error

SetBkColor failed

Error message

SetBkColor failed

What it means

Error "SetBkColor failed" thrown in wailsapp/wails.

Source

Thrown at v3/pkg/w32/gdi32.go:428

func SetTextColor(hdc HDC, crColor COLORREF) COLORREF {
	ret, _, _ := procSetTextColor.Call(
		uintptr(hdc),
		uintptr(crColor))

	if ret == CLR_INVALID {
		panic("SetTextColor failed")
	}

	return COLORREF(ret)
}

func SetBkColor(hdc HDC, crColor COLORREF) COLORREF {
	ret, _, _ := procSetBkColor.Call(
		uintptr(hdc),
		uintptr(crColor))

	if ret == CLR_INVALID {
		panic("SetBkColor failed")
	}

	return COLORREF(ret)
}

func StartDoc(hdc HDC, lpdi *DOCINFO) int {
	ret, _, _ := procStartDoc.Call(
		uintptr(hdc),
		uintptr(unsafe.Pointer(lpdi)))

	return int(ret)
}

func StartPage(hdc HDC) int {
	ret, _, _ := procStartPage.Call(
		uintptr(hdc))

	return int(ret)

View on GitHub (pinned to 0e754b1b40)

Solutions

1. Pass a valid HDC that supports text output; SetBkColor fails on invalid or deleted device contexts.
2. Ensure the COLORREF value is a valid RGB value created with the RGB macro; an invalid color value causes the call to return CLR_INVALID.

When it happens

Trigger: Occurs when SetBkColor returns CLR_INVALID, typically due to an invalid device context handle or an invalid color value.

Common situations: See trigger scenarios.

AI-assisted analysis of wailsapp/wails@0e754b1b40 (2026-08-15). Data as JSON: /api/errors/3f559fce6a743ecb. Report an issue: GitHub.