| Class TDrawMetaFile (unit xyMeta) |
TMetaFile
this unit was orignally called unit DrawMeta; I have renamed it so that it is easily identified with xyGraph. If you already have DrawMeta you might want to delete this and change the uses clause in xyGraph to use drawmeta. Note that this file is only required for D1.0} {--- make a drawable metafile ---} { Grahame Marsh Jan 1996
| Constructors |
constructor Create (aWidth, aHeight : integer);| Functions |
procedure Close;
destructor Destroy;
procedure Open;
procedure SetDrawing (State : boolean);| Properties |
property Canvas : TCanvas
property Drawing : boolean| Events |
| Variables |
FCanvas : TCanvas;
FDrawing : boolean;| Constructors |
constructor Create (aWidth, aHeight : integer);create our drawing metafile, take the drawing width and height to those } { given in the parameters, set the inch property to that found in } { screens.pixelsperinch and finally open for drawing
| Functions |
procedure Close;
destructor Destroy;before destroying the metafile ensure that it is closed, this means } { that any canvas is destroyed
procedure Open;
procedure SetDrawing (State : boolean);The key method: puts the metafile into draw and use modes depending on } { the boolean parameter. When true the metafile goes into draw mode by } { putting a CreateMetafile device context into a Canvas handle property } { the canvas can now be drawn on. When false the metafile goes into use } { mode by putting the handle returned from the CloseMetafile call into } { the metafile's handle property. Note that the width, height and inch } { properties are preserved over this assignment. Finally the canvas is } { freed.
| Properties |
property Canvas : TCanvas
property Drawing : boolean| Events |
| Variables |
FCanvas : TCanvas;
FDrawing : boolean;