api:dk11:delphi:fmx.giscontrolprintpreview.tgis_printpreviewfactoryfmx.preview_igis_viewer_tgis_printmanagerabstract_string_double_string_aff7e2281ec47a65fed715439c2bf861
Table of Contents
TGIS_PrintPreviewFactoryFMX.Preview method
DK for Delphi | FMX.GisControlPrintPreview.TGIS_PrintPreviewFactoryFMX.Preview | Methods
Executes print preview for the specified viewer and print manager.
Syntax
Overrides TGIS_PrintPreviewFactory.Preview.
// Delphi public procedure Preview( const _viewer : IGIS_Viewer; const _printManager : TGIS_PrintManagerAbstract; const _customPage : String; var _scale : Double; const _caption : String; const _left : Integer; const _top : Integer; const _width : Integer; const _height : Integer; const _state : TWindowState; const _help : TGIS_HelpEvent ); override;
// C++ Builder public: virtual void Preview( IGIS_Viewer* const _viewer, TGIS_PrintManagerAbstract* const _printManager, const UnicodeString _customPage, double &_scale, const UnicodeString _caption, const int _left, const int _top, const int _width, const int _height, TWindowState* const _state, TGIS_HelpEvent* const _help );
Parameters
| Name | Type | Description |
|---|---|---|
| _viewer | IGIS_Viewer | Viewer to preview. |
| _printManager | TGIS_PrintManagerAbstract | Print manager that provides printing settings and content. |
| _customPage | String | Custom page format identifier. |
| _scale | Double | Scale factor used during printing. If _scale = 0, the value is calculated automatically to fit the print extent. |
| _caption | String | Caption for the preview window. |
| _left | Integer | Left X coordinate of the rectangle to print. |
| _top | Integer | Top Y coordinate of the rectangle to print. |
| _width | Integer | Width of the rectangle to print. |
| _height | Integer | Height of the rectangle to print. |
| _state | TWindowState | Window state parameter reserved for framework-specific use and not used by this abstraction. |
| _help | TGIS_HelpEvent | Help event callback for the preview window. |
Remarks
PURPOSE: Opens a framework-dependent print preview for a viewer using the supplied print manager and page settings.
BEHAVIOR: Uses the specified print rectangle, caption, and custom page format. The _scale parameter is passed by reference so an implementation can update it when automatic scaling is used.
CONSTRAINTS: Printing fails when _viewer.InPaint is True. This method is abstract and must be implemented by a framework-specific descendant.
2026/07/11 00:18