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   <TITLE>Start a program minimized</TITLE>

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

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<H3>

Start a program minimized<BR>

</H3>

<BR>



<P>

You can call the <TT>Application-&gt;Minimize</TT> function to

minimize a program to the taskbar. If you want your program to start minimized,

then simply call <TT>Application-&gt;Minimize</TT> in the <TT>WinMain</TT> function

before the <TT>Run</TT> method is called.

</P>

<pre>

WINAPI WinMain<b>(</b>HINSTANCE<b>,</b> HINSTANCE<b>,</b> LPSTR<b>,</b> <b>int</b><b>)</b>

<b>{</b>

    <b>try</b>

    <b>{</b>

        Application<b>-></b>Initialize<b>(</b><b>)</b><b>;</b>

        Application<b>-></b>CreateForm<b>(</b><b>__classid</b><b>(</b>TForm1<b>)</b><b>,</b> <b>&</b>Form1<b>)</b><b>;</b>

        Application<b>-></b>Minimize<b>(</b><b>)</b><b>;</b>

        Application<b>-></b>Run<b>(</b><b>)</b><b>;</b>

    <b>}</b>

    <b>catch</b> <b>(</b>Exception <b>&</b>exception<b>)</b>

    <b>{</b>

        Application<b>-></b>ShowException<b>(</b><b>&</b>exception<b>)</b><b>;</b>

    <b>}</b>

    <b>return</b> <font color="blue">0</font><b>;</b>

<b>}</b>

</pre>

<H3>Note for C++Builder 1.0 users</H3>

<P>The steps that follow pertain only to C++Builder 1. If you use C++Builder 3 or newer, you can ignore the rest of this

FAQ.

</p>

<P>

The file \VCL\SYSTEM.PAS contains a function called <TT>_InitExe</TT> that runs when the program starts.

<TT>_InitExe</TT>  contains this statement

</P>

<PRE>

        MOV     CmdShow,10      { SW_SHOWDEFAULT }

</PRE>

<P>

The global <TT>CmdShow</TT> variable determines the state of program on

startup. In theory, you could set <TT>CmdShow</TT> to <TT>SW_MINIMIZE</TT>

to start a program minimized, but because <TT>_InitExe</TT> hardcodes a

value into <TT>CmdShow</TT>, your assignment gets overwritten. Because of

this assignment in <TT>_InitExe</TT>, applications cannot begin minimized.

The best we can do is to minimize the program as soon as we get a chance

from code. The main form will flash briefly on the screen before being

minimized, but we can prevent this by telling <TT>TApplication</TT> to keep

the main form hidden when the program starts.

</P>

<B>Step 1:</B> Choose View|Project Source from the C++Builder menu so you

can edit the <TT>WinMain</TT> function. Call the <TT>Minimize</TT> method of

<TT>TApplication</TT> to minimize the program to the taskbar. Set

<TT>ShowMainForm</TT> to <TT>false</TT> to prevent the main form from

flashing on the screen. Modify <TT>WinMain</TT> as follows:

</P>

<pre>

WINAPI WinMain<b>(</b>HINSTANCE<b>,</b> HINSTANCE<b>,</b> LPSTR<b>,</b> <b>int</b><b>)</b>

<b>{</b>

    <b>try</b>

    <b>{</b>

        Application<b>-></b>Initialize<b>(</b><b>)</b><b>;</b>

        Application<b>-></b>CreateForm<b>(</b><b>__classid</b><b>(</b>TForm1<b>)</b><b>,</b> <b>&</b>Form1<b>)</b><b>;</b>

        Application<b>-></b>ShowMainForm <b>=</b> <b>false</b><b>;</b>

        Application<b>-></b>Minimize<b>(</b><b>)</b><b>;</b>

        Application<b>-></b>Run<b>(</b><b>)</b><b>;</b>

    <b>}</b>

    <b>catch</b> <b>(</b>Exception <b>&</b>exception<b>)</b>

    <b>{</b>

        Application<b>-></b>ShowException<b>(</b><b>&</b>exception<b>)</b><b>;</b>

    <b>}</b>

    <b>return</b> <font color="blue">0</font><b>;</b>

<b>}</b>

</pre>



<P>

<B>Step 2:</B> Setting <TT>ShowMainForm</TT> to <TT>false</TT> has one bad

side effect. The form will not appear when the user restores the program by

clicking on the taskbar icon. You can solve this problem by creating an

<TT>OnRestore</TT> handler for the application. Open the header file for the

main form and add this prototype to your main form's class.

</P>

<pre>

<b>private</b><b>:</b>	<font color="navy">// User declarations</font>

    <b>void</b> <b>__fastcall</b> AppRestore<b>(</b>TObject <b>*</b>Sender<b>)</b><b>;</b>

</pre>



<P>

<B>Step 3:</B> Open the main form's CPP file and code the

<TT>AppRestore</TT> function.

</P>

<pre>

<b>void</b> <b>__fastcall</b> TForm1<b>:</b><b>:</b>AppRestore<b>(</b>TObject <b>*</b>Sender<b>)</b>

<b>{</b>

    Visible <b>=</b> <b>true</b><b>;</b>

<b>}</b>

</pre>



<P>

<B>Step 4:</B> Assign the <TT>AppRestore</TT> function to the

<TT>OnRestore</TT> handler of <TT>TApplication</TT>. Make this assignment

in the constructor of the main form.

</P>

<pre>

<b>__fastcall</b> TForm1<b>:</b><b>:</b>TForm1<b>(</b>TComponent<b>*</b> Owner<b>)</b>

	<b>:</b> TForm<b>(</b>Owner<b>)</b>

<b>{</b>

    Application<b>-></b>OnRestore <b>=</b> AppRestore<b>;</b>

<b>}</b>

</pre>





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