LoadingText property

LoadingText is the caption that the viewer overlays on top of a partially-rendered page when AsyncRendering is True. The viewer measures the string with its current inherited font, expands the result into a centred rectangle, fills it with LoadingColor, and then draws the text on top. The default 'Loading...' is recognisable to users as a transient state and is wide enough to be visible without dominating the page.

The overlay is keyed off the text rather than off a separate visibility flag. Assigning an empty string ('') suppresses the overlay even while asynchronous rendering is active — useful when the host application wants to display its own loading widget (an animated GIF, a modal progress dialog, a separate status-bar panel) and would rather not have the built-in rectangle compete for attention.

Localise the string by assigning a translated resource at startup; the property accepts any string the host application can produce, including multi-byte characters such as Chinese, Japanese, or Arabic.

• The rectangle is sized to the rendered text. A long string therefore produces a wider badge; keep it short for a compact indicator.
• The overlay is drawn after the page bitmap, so it is always visible even when the page has partially painted underneath.
• To hide the indicator without disabling asynchronous rendering, clear LoadingText; to disable async rendering entirely, set AsyncRendering to False.