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Is it possible to change a line color of a RichEdit without selection?

Is it possible to change a line color of a RichEdit without selection?
0
raunol
Asked:
raunol
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1 Solution
 
ZifNabCommented:
This should do it.

Selection is needed to color it, after the coloring we don't need selection any more. Hope this is enough.

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ColorGrd, StdCtrls, ComCtrls;

type
  TForm1 = class(TForm)
    RichEdit1: TRichEdit;
    Edit1: TEdit;
    Label1: TLabel;
    Button1: TButton;
    ColorGrid1: TColorGrid;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);

  var
    iStart, iEnd: longint;
    iSelStart, iSelEnd: longint;
    iOldCount: longint;

  begin
  with RichEdit1 do
    begin
    Lines.BeginUpdate;
    try
      // get current position
      SendMessage( Handle, EM_GETSEL, LongInt( @iStart ), LongInt( @iEnd ) );
      // find out how many lines we have before we add this text
      iOldCount := Lines.Count;
      // add the text
      Lines.Add( Edit1.Text );
      // select newly added text
      // The start index will always be the first line after the old
      // count (line count is not zero-based, so we don't have to add 1)
      iSelStart := SendMessage( Handle, EM_LINEINDEX, iOldCount, 0 );
      // The length of our selection will always be the position we start
      // from plus the length of the text that was added.
      iSelEnd := iSelStart + Length( Edit1.Text );
      SendMessage( Handle, EM_SETSEL, iSelStart, iSelEnd );
      // change the color of the text
      with SelAttributes do
        Color := ColorGrid1.ForegroundColor;
      // return to saved position
      SendMessage( Handle, EM_SETSEL, iStart, iEnd );
    finally
      Lines.EndUpdate;
      end;
    end;
  end;

end.

Regards, Zif.
0
 
raunolAuthor Commented:
Hi,

Good idea! Thank You very much, Zif.

It works just like I want, a selection not
flashes during colouring. I feel that Perform
function is rather nicer code to use than Sendmessage,
like this:

//colouring of the current line
Procedure TForm1.Button1Click(Sender: TObject);
var
    iStart, iEnd: longint;
    iSelStart, iSelEnd: longint;
    CurrentLine:Longint;
Begin
Whit RichEdit1 do
Begin
               Lines.BeginUpdate;  
      Perform(EM_GETSEL, LongInt( @iStart ), LongInt( @iEnd ));
               //Get the current line
      CurrentLine:=Perform(EM_LINEFROMCHAR,SelStart,0);
      //Starpos in the begin of the line
            iSelStart:= Perform(EM_LINEINDEX,CurrentLine, 0 );
                 iSelEnd := iSelStart+Length(Lines[CurrentLine]);
            Perform(EM_SETSEL, iSelStart, iSelEnd );
            // change the color of the text
            SelAttributes.Color := clRed;
            // return to saved position
            Perform(EM_SETSEL, iStart, iEnd );
            Lines.EndUpdate;
      Setfocus;
End;


- Rauno


0
 
ZifNabCommented:
Yep Rauno, it's nicer with perform. regards, ZiF.
0
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raunolAuthor Commented:
Hi, Zif

Thanks for Your comment. Dont be sorry, but
in fact, I was glad too early. The selection
still flashes when to colour a line which is
longer. So Your answer wasn't perfect for my problem:
How to colour line without selection.

Anyway You gave a good advice using of api
functions.


- Rauno



0
 
ZifNabCommented:
Sorry, it doesn't works. I'll look for a solution.
0
 
raunolAuthor Commented:
Hi, Zif

Now, I found a one solution my self.

First we must add "RichEdit" -unit to USES section

Then it's possible to use Sendmessage or
perform function:
RichEdit1.Perform(EM_HIDESELECTION,1,0)
And voila! No selection flashes during colouring.

- Rauno

0
 
ZifNabCommented:
Hi Rauno,

Great solution! Thanks for letting me know of this!

Regards Zif.
0

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