Get the selected text data.

[SethLK]

When text is selected, how do you get that data without copying it?
How do I implement the custom selection toolbar? For instance, other PDF viewer apps have these:

• copy
• select all
• etc

after selected.

[espresso3389]

On the today's Flutter 3.27 release, Flutter introduces a way to get SelectableRegionState from SelectionArea using GlobalKey.

SelectableRegionState has the following methods:

• clearSelection
• selectAll

But for copy, copySelection is recently deprecated because of the iOS copy notification issue.

And, because pdfrx internally embed SelectionArea inside PdfViewer, you should use PdfViewerParams.perPageSelectableRegionInjector to replace the embedded one like this:

final selectionAreaKey = GlobalKey<SelectableRegionState>();

PdfViewer.file(
  ...,
  params: PdfViewerParams(
    perPageSelectableRegionInjector: (context, child, page, pageRect) {
      return SelectionArea(
        key: selectionAreaKey,
        onSelectionChanged: (selection) { /* some code to handle selection change */ },
        child: child,
      );
    }
  ),
  ...

// clear selection
final selectableRegionState = selectionAreaKey.state;
state?.clearSelection();

Of course, pdfrx has PdfViewerParams.onTextSelectionChange method to be notified when text selection change, which has better control on PDF structure.