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📁 翁剀JAVA语言那门课程的教案很多人都看多他的视频教程可惜没有ppt的教案
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<h2>
12.4 CardLayout</h2>

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<br>The CardLayout allows you to create the rough equivalent of a "tabbed
dialog", which in more sophisticated environments has actual file-folder
tabs running across one edge, and all you have to do is press a tab to
bring forward a different dialog. Not so in the AWT: The CardLayout is
simply a blank space and you're responsible for bringing forward new cards.
(The JFC/Swing library contains tabbed panes that look much better and
take care of all the details for you.)
<p>This example will combine more than one layout type, which seems rather
difficult at first since only one layout manager can be operating for an
applet or application. This is true, but if you create more Panel objects,
each one of those Panels can have its own layout manager and then be integrated
into the applet or application as simply another component, using the applet
or application's layout manager. This gives you much greater flexibility
as seen in the following example:
<p>Case Study: <a href="case/Layout/CardLayout1.java">CardLayout1.java</a>
<p><applet code=CardLayout1 width=200 height=200 codebase=case/Layout></applet>
<p>This example begins by creating a new kind of Panel: a ButtonPanel.
This contains a single button, placed at the center of a BorderLayout,
which means that it will expand to fill the entire panel. The label on
the button will let you know which panel you're on in the CardLayout.
<p>In the applet, both the Panel cards where the cards will live and the
layout manager cl for the CardLayout must be members of the class because
you need to have access to those handles when you want to manipulate the
cards.
<p>The applet is changed to use a BorderLayout instead of its default FlowLayout,
a Panel is created to hold three buttons (using a FlowLayout), and this
panel is placed at the "worth" end of the applet. The cards panel is added
to the "center" of the applet, effectively occupying the rest of the real
estate.
<p>When you add the ButtonPanels (or whatever other components you want)
to the panel of cards, the add( ) method's first argument is not "North",
"South", etc. Instead, it's a string that describes the card. Although
this string doesn't show up anywhere on the card, you can use it if you
want to flip that card using the string. This approach is not used in action(
);
<br>instead the first( ), next( ), and lst( ) methods are used. Check your
documentation for the
<br>other approach.
<p>In Java, the use of some sort of "tabbed panel" mechanism is quite important
because (as you'll see later) in applet programming the use of pop-up dialogs
is heavily discouraged. For Java 1.0 applets, the CardLayout is the only
viable way for the applet to have a number of different forms that "pop
up" on command.
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