application.terminate;
You may want the program to do other things first, for example giving the user a chance to change his/ her mind. If the program involves an .ini file or data which may need saving, then if it has be altered since the last save, it is usual in Windows programs to check with the user:'Work not saved. Save it now/ No/ Cancel?' (Working with data from files is beyond the scope of this tutorial, but is covered in later tutorials.)
You can test your menu and the File|Quit option now.
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For the 'About' option, we will create some text which will appear and which can be made to go away again.
The approach taken here to doing an 'About' panel differs from that in the excellent Delphi (ver 1) manual. Each has its merits.
Before you begin, resize the whole form to something reasonable.
a) Add a panel ('standard' component) to your form. Name it pAbout. Make it as wide as your form, but only high enough to show one line of text. Move it (up or down) to an out of the way place on your form.
Panels are great because they are 'container' components. We will put things on the panel, and because they are 'contained' by the panel. we can do things to the whole collection with single actions.
b) Don't be alarmed by the result of the next change. Set the panel's Align property (not AlignMENT) to alClient.
c) Put a button on the panel. Name it bpAboutOK; Caption: OK.
d) Put a memo component on the panel. Name it mpAboutMemo; align alClient; make enabled false (Stops users changing 'About' text. Changes wouldn't be permanant, anyway.)
e) When you added the memo, your 'OK' button probably disappeared. Use the listbox at the top of the object inspector to select bpAboutOK. The little black squares mariking a selected item appear on the form. RIGHT-click somewhere within the selection squares. Select 'Bring to Front' from the menu. Move it to some tidy place. If your form gets resized, the button will only maintain its distance down and over from the upper left hand corner. If the form gets too small, scroll bars will appear.
f) Reselect mpAboutMemo. Be careful in this work that you are getting the object you want. It is easy to get mpAboutMemo instead of pAbout.
We are going to put some text on the panel. Now... I must confess: I do not fully grasp all of the details of what I'm about to delve into... but what I'm suggesting works! (The problems that you can encounter involve having 'returns' embedded in your text at places you don't want them. There's a complex interplay between the following memo properties: Enabled, Scrollbars, Wordwrap. The WantReturns property is not involved in this issue. While the memo's Enabled property is false, the setting of WantReturns is irrelevant. Setting WordWrap true won't fix everything for you... the system inserts extra returns into the text to reflect the width of mpAboutMemo when the program was compiled... but having it set true is better than having it set false: The layout may be poor, but at least no text is lost. Leave Scrollbars ssNone. They won't work while Enabled is false, anyway, nor will they automatically disappear if not needed.
(If you want to try to get to the bottom of all of this, you may be happier working with the panel's and memo's align properties set to alNone)
mpAboutMemo should be selected at this point. Double-click on the Lines property. The String List Editor pops up. Delete the default mpAboutMemo which is there. Enter the panel's text. Typical 'About' test includes the program's name, vendor address, and copyright messages. My imperfect sustem requires that you press enter near the end of lines, as in the bad old days of manual typewriters. Press enter twice to create blank lines between paragraphs. When the text is complete, click on the editor's 'OK' button. (You don't need to use the 'save' button.)
The system is good at adding new returns if the memo isn't wide enough... but it isn't good at taking them out again if the memo gets wider.
You may want to set the memo's Alignment property to alCenter. This centers each line of the memo's text in the space available.
Anyway... it may not look perfect, but there should be some useful content, anyway.
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Once you are happy with your text, you need a way to 'hide' it while you work on the rest of the project. Set pAbout's Align property to alNone and resize the panel to be very narrow vertically. Horizontally, don't make it narrower than the form. If you want extra 'hiding', select the panel, right-click, click on 'Send To Back'.
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Now we come to writing the code to make the About panel appear and disappear.
a) Create an OnCreate event for the form, if there isn't one already. Put the following in it:
pAbout.hide;
b) Create an OnClick event for mmAbout as follows:
pAbout.show;
pAbout.bringtofront;
pAbout.align:=alClient;
bpAboutOK.setfocus;
c) Use the object inspector to select bpAboutOK. (It doesn't matter if you have the panel minimized.) Create an OnClick event which says
pAbout.hide;
And there you have it!
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An extension:
If you like to put version indicators into your programs, as you should, you can fool around with the Lines property of mpAboutMemo each time the version number changes, or you can....
Select pAbout, set Align alNone.
Add an edit box. Call it epAboutVersion. Be sure it is in front of the memo. Make Autosize false, Enabled false.
In the FormCreate procedure, add epAboutVersion.text:='Version 0.00';
(Labels don't work well for something like the Version field. They are always under controls (e.g. memos or buttons) on the panel. Furthermore, unless their Transparent property is made True, they can blot each other out. 'Sent to Front' still has a bearing, but only in 'stacking' the labels, all of which are under the controls.)
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