property LoadingColor: TColor; // default clYellow
When AsyncRendering is True the viewer draws a placeholder rectangle in the centre of the visible page while the actual page bitmap is still being generated. LoadingColor controls the background of that rectangle. The default clYellow provides high contrast against the typical white page bitmap so the indicator is clearly visible even when the page has already started to paint behind it.
The placeholder is only painted when LoadingText is non-empty — the text is what gives the rectangle its size. Setting LoadingText to an empty string disables the overlay entirely regardless of LoadingColor.
Changing LoadingColor at runtime takes effect on the next paint cycle. The colour does not affect the actual rendered PDF content, only the loading indicator.
$00F0F0F0); for a prominent one pick a saturated colour such as clYellow or clRed.'Rendering...' for a polished feel similar to web spinners.// Enable an Adobe-style loading badge in the centre of the page.
PdfView1.AsyncRendering := True;
PdfView1.LoadingColor := $00E0E0E0; // light grey
PdfView1.LoadingText := 'Rendering page...';
// Switch to a high-contrast badge for accessibility-mode UI.
if AccessibilityHighContrast then
begin
PdfView1.LoadingColor := clBlack;
PdfView1.Font.Color := clYellow;
end;