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<a href="http://www.bruceeckel.com/javabook.html">Bruce Eckel's Thinking in Java</a>
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<H2 ALIGN=LEFT>
Making
a button
</H2>
<DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Making
a button is quite simple: you just call the <A NAME="Index1574"></A><A NAME="Index1575"></A></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>Button</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
constructor with the label you want on the button. (You can also use the
default constructor if you want a button with no label, but this is not very
useful.) Usually you&#8217;ll want to create a handle for the button so you can
refer to it later.
</FONT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">The
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>Button</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
is a component, like its own little window, that will automatically get
repainted as part of an update. This means that you don&#8217;t explicitly
paint a button or any other kind of control; you simply place them on the form
and let them automatically take care of painting themselves. So to place a
button on a form you override 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>init(&#160;)
</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">instead
of overriding 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>paint(&#160;)</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">:</FONT><P></DIV>

<font color="#990000"><PRE><font color="#009900">//: Button1.java</font>
<font color="#009900">// Putting buttons on an applet</font>
<font color="#0000ff">import</font> java.awt.*;
<font color="#0000ff">import</font> java.applet.*;

<font color="#0000ff">public</font> <font color="#0000ff">class</font> Button1 <font color="#0000ff">extends</font> Applet {
  Button 
    b1 = <font color="#0000ff">new</font> Button("Button 1"), 
    b2 = <font color="#0000ff">new</font> Button("Button 2");
  <font color="#0000ff">public</font> <font color="#0000ff">void</font> init() {
    add(b1);
    add(b2);
  }
} <font color="#009900">///:~ </PRE></font></font><DIV ALIGN=LEFT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">It&#8217;s
not enough to create the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>Button</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
(or any other control). You must also call the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>Applet</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>add(&#160;)</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
method to cause the button to be placed on the applet&#8217;s form. This seems
a lot simpler than it is, because the call to 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>add(&#160;)</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
actually decides, implicitly, where to place the control on the form.
Controlling the layout of a form is examined shortly.
</FONT><a name="_Toc375545448"></a><a name="_Toc408018684"></a><P></DIV>

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