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   <TITLE>Change the text color on a push button</TITLE>

   <META NAME="Author" CONTENT="Harold Howe">

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<H3>

Change the text color on a push button

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<P>

A standard windows push button does not allow you to easily change the color of its text.

This explains why changing the font properties of a standard <TT>TButton</TT> doesn't have

any impact. In order to change the text color of a button, you must either subclass the

control or owner draw the control. Fortunately, C++Builder provides a simple workaround.

The <TT>BitBtn</TT> control already owner draws itself. In fact, it owner draws itself

even if you don't display a glyph on the button.

</P>

<P>

To change the color of the text on a button, simply replace it with a <TT>BitBtn</TT>

component. Set the text color using the <TT>Font</TT> property of the button.

</P>

<P>

<B>Note:</B> You can prove that <TT>TBitBtn</TT> is owner drawing itself by looking at the

<TT>CreateParams</TT> member function. It looks like this (converted to C++):

</P>



<pre>

<b>void</b> <b>__fastcall</b> TBitBtn<b>:</b><b>:</b>CreateParams<b>(</b>TCreateParams <b>&</b>Params<b>)</b>

<b>{</b>

    TButton<b>:</b><b>:</b>CreateParams<b>(</b>Params<b>)</b><b>;</b>

    Params<b>.</b>Style <b>|=</b> BS_OWNERDRAW<b>;</b>

<b>}</b>

</pre>



<P>

<B>Note:</B> After proving that <TT>TBitBtn</TT> is using old-fashioned owner drawing, you

can then see for yourself how <TT>TBitBtn</TT> uses the <TT>Font</TT> property. Look

inside the <TT>TBitBtn::DrawItem</TT> function. You should see something like this inside

the function (once again, I converted the code to C++ and added comments):

</P>

<pre>

<font color="navy">// FCanvas is the canvas that the button is painted with.</font>

<font color="navy">// this->Font is the Font property of the control</font>

FCanvas<b>-></b>Font <b>=</b> <b>this</b><b>-></b>Font<b>;</b>



<font color="navy">// after setting the font, a function is called the draws the glyph,</font>

<font color="navy">// the text, and the background of the button using FCanvas</font>

</pre>





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