Integrera PDFium VCL Component-flöden i Delphi- och C++Builder-applikationer, eller PDFium LCL Component-flöden i Lazarus/FPC, med källkodskomponenter för visning, rendering, formulär, utskrift, preflight-rapporter och standardinriktad validering.
Den här artikeln är skriven för teams adding review, markup, approval, or quality-control panels to a Delphi PDF viewer. Den behandlar annotation review UI som produktionsnära dokumentteknik, inte som ett isolerat komponentanrop.
Den praktiska risken är att annotations are easy to display but hard to trust when page rotation, authorship, replies, hidden states, or coordinate conversions are not handled consistently. Därför behöver flödet ett skrivet kontrakt, observerbar diagnostik och realistiska regressionsfiler.
Arkitekturbeslut
Separate review state from page rendering. which annotation types can be viewed, filtered, replied to, exported, or locked / author identity, status labels, and whether review data is stored in the PDF
- which annotation types can be viewed, filtered, replied to, exported, or locked
- author identity, status labels, and whether review data is stored in the PDF
- coordinate conversion for rotation, zoom, crop boxes, and high-DPI displays
- read-only mode for signed, protected, or externally governed documents
Implementeringsflöde
Index annotations before showing review actions. The order below keeps the workflow reviewable for Delphi and C++Builder teams.
- load annotation metadata into a review index before painting page overlays
- normalize page coordinates and keep a stable reference for every annotation
- apply filters by author, status, type, page, and date without re-parsing pages
- tie selection in the review list to viewport navigation and highlight behavior
- export review summaries with enough context for non-viewer workflows
Valideringsbevis
Review evidence that supports collaboration. Keep these fields with the output or support record.
- annotation type, author, page, bounds, status, and reply count
- coordinate transform used for the current zoom, rotation, and crop box
- permission decision when a user attempts to edit a locked or signed document
- exported review summary with stable page references
Coordinates and intent matter
A professional review UI treats annotations as structured data with authors, dates, page locations, appearance, replies, status, and permissions. The canvas view is only one presentation of that model.
Customer-visible behavior
Users do not see internal call order. They see whether the file opens, validates, prints, edits, imports, or gets rejected. The workflow should translate annotation review UI results into states users can act on.
- load annotation metadata into a review index before painting page overlays
- normalize page coordinates and keep a stable reference for every annotation
- apply filters by author, status, type, page, and date without re-parsing pages
- rotated pages can make highlights appear detached from the original text
- popup annotations and replies may be missed when only visible marks are scanned
Engineering review notes for annotation review UI
Use these review notes to make sure the feature has moved beyond a demo and can be defended during release, support, and customer escalation.
- Decision: which annotation types can be viewed, filtered, replied to, exported, or locked. Implementation pressure point: normalize page coordinates and keep a stable reference for every annotation. Acceptance evidence: permission decision when a user attempts to edit a locked or signed document. Regression trigger: annotations on cropped pages need coordinates tied to the intended page box
- Decision: author identity, status labels, and whether review data is stored in the PDF. Implementation pressure point: apply filters by author, status, type, page, and date without re-parsing pages. Acceptance evidence: exported review summary with stable page references. Regression trigger: rotated pages can make highlights appear detached from the original text
- Decision: coordinate conversion for rotation, zoom, crop boxes, and high-DPI displays. Implementation pressure point: tie selection in the review list to viewport navigation and highlight behavior. Acceptance evidence: annotation type, author, page, bounds, status, and reply count. Regression trigger: popup annotations and replies may be missed when only visible marks are scanned
- Decision: read-only mode for signed, protected, or externally governed documents. Implementation pressure point: export review summaries with enough context for non-viewer workflows. Acceptance evidence: coordinate transform used for the current zoom, rotation, and crop box. Regression trigger: read-only review must still allow selection, navigation, filtering, and export
- Decision: which annotation types can be viewed, filtered, replied to, exported, or locked. Implementation pressure point: load annotation metadata into a review index before painting page overlays. Acceptance evidence: permission decision when a user attempts to edit a locked or signed document. Regression trigger: annotations on cropped pages need coordinates tied to the intended page box
- Decision: author identity, status labels, and whether review data is stored in the PDF. Implementation pressure point: normalize page coordinates and keep a stable reference for every annotation. Acceptance evidence: exported review summary with stable page references. Regression trigger: rotated pages can make highlights appear detached from the original text
- Decision: coordinate conversion for rotation, zoom, crop boxes, and high-DPI displays. Implementation pressure point: apply filters by author, status, type, page, and date without re-parsing pages. Acceptance evidence: annotation type, author, page, bounds, status, and reply count. Regression trigger: popup annotations and replies may be missed when only visible marks are scanned
Gränsfall
- rotated pages can make highlights appear detached from the original text
- popup annotations and replies may be missed when only visible marks are scanned
- read-only review must still allow selection, navigation, filtering, and export
- annotations on cropped pages need coordinates tied to the intended page box
Delphi / C++Builder notes
PDFium Component should sit behind a small service boundary that receives files, streams, profiles, and credentials, then returns output paths, warnings, metrics, and validation status. Important terms include annotation, markup, reply, page bounds, rotation, review status.
Delphi-kodexempel
Följande Delphi-skiss visar en praktisk servicegräns för detta ämne. Håll policykontroller, loggning och validering utanför det smala produktanropet så att arbetsflödet går att testa.
procedure TReviewForm.LoadAnnotationQueue(const FileName: string);
var
PageNo: Integer;
begin
PdfView.LoadFromFile(FileName);
FQueue.Clear;
for PageNo := 1 to PdfView.PageCount do
AddPageAnnotationsToQueue(PdfView, PageNo, FQueue);
FQueue.SortByAuthorAndDate;
ShowNextReviewItem;
end;Produktionschecklista
- Run the workflow on an empty file, a normal customer file, and a worst-case file
- Open the generated PDF with the target viewer, validator, printer, or downstream application
- Log product version, profile version, input hash, output path, elapsed time, and warning count
- Keep passwords, certificates, temporary files, and customer data under explicit retention rules
- Add regression documents when a customer file exposes a new edge case