Docs de PDFiumVCL

OnMouseDown event

Esta entrada API conserva identificadores, firmas, bloques de código y términos PDF en su forma original.
Component: TPdfView  ·  Unit: PDFium
Fired when the user presses a mouse button over the view.

Syntax

property OnMouseDown: TMouseEvent;

Description

Fired when the user presses a mouse button over the view. The Sender parameter references the TPdfView instance that raised the event, so a single handler can serve multiple views by inspecting Sender.

Typical uses include: begin a custom selection box, start panning, or capture coordinates for a "go to this annotation" feature. Because the handler runs on the VCL main thread, you can update form controls and call other VCL APIs directly.

Handlers must return quickly — PDFium rendering and form filling occur on the same thread, and any delay here postpones the next page repaint.

Remarks

Example

procedure TForm1.PdfViewOnMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
  // begin a custom selection box, start panning, or capture coordinates for a "go to this annotation" feature
  Caption := Format('OnMouseDown on page %d', [PdfView1.PageNumber]);
end;

See Also

OnClick, OnPageChange, PageNumber