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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>
Text
fields
</H2>
<DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">A
<A NAME="Index1606"></A><A NAME="Index1607"></A></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextField</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
is a one line area that allows the user to enter and edit text. 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextField
</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">is
inherited from <A NAME="Index1608"></A><A NAME="Index1609"></A></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextComponent</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">,</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>
</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">which
lets you select text, get the selected text as a 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>String</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">,
get or set the text, and set whether the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextField</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
is editable, along with other associated methods that you can find in your
online reference. The following example demonstrates some of the functionality
of a 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextField</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">;
you can see that the method names are fairly obvious:
</FONT><P></DIV>

<font color="#990000"><PRE><font color="#009900">//: TextField1.java</font>
<font color="#009900">// Using the text field control</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> TextField1 <font color="#0000ff">extends</font> Applet {
  Button
    b1 = <font color="#0000ff">new</font> Button("Get Text"),
    b2 = <font color="#0000ff">new</font> Button("Set Text");
  TextField 
    t = <font color="#0000ff">new</font> TextField("Starting text", 30);
  String s = <font color="#0000ff">new</font> String();
  <font color="#0000ff">public</font> <font color="#0000ff">void</font> init() {
    add(b1);
    add(b2);
    add(t);
  }
  <font color="#0000ff">public</font> <font color="#0000ff">boolean</font> action (Event evt, Object arg) {
    <font color="#0000ff">if</font>(evt.target.equals(b1)) {
      getAppletContext().showStatus(t.getText());
      s = t.getSelectedText();
      <font color="#0000ff">if</font>(s.length() == 0) s = t.getText();
      t.setEditable(<font color="#0000ff">true</font>);
    }
    <font color="#0000ff">else</font> <font color="#0000ff">if</font>(evt.target.equals(b2)) {
      t.setText("Inserted by Button 2: " + s);
      t.setEditable(<font color="#0000ff">false</font>);
    }
    <font color="#009900">// Let the base class handle it:</font>
    <font color="#0000ff">else</font> 
      <font color="#0000ff">return</font> <font color="#0000ff">super</font>.action(evt, arg);
    <font color="#0000ff">return</font> <font color="#0000ff">true</font>; <font color="#009900">// We've handled it here</font>
  }
} <font color="#009900">///:~ </PRE></font></font><DIV ALIGN=LEFT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">There
are several ways to construct a 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>TextField</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">;
the one shown here provides an initial string and sets the size of the field in
characters.
</FONT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Pressing
button 1 either gets the text you&#8217;ve selected with the mouse or it gets
all the text in the field and places the result in 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>String
s
</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">.
It also allows the field to be edited. Pressing button 2 puts a message and 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>s</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
into the text field and prevents the field from being edited (although you can
still select the text). The editability of the text is controlled by passing <A NAME="Index1610"></A><A NAME="Index1611"></A></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>setEditable(&#160;)</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
a 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>true</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
or 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>false</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">.</FONT><a name="_Toc375545450"></a><a name="_Toc408018686"></a><P></DIV>

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