📄 pos.htm
字号:
<HTML>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<TITLE>Using a Position in a JTextComponent (Java Developers Almanac Example)
</TITLE>
<META CONTENT="Patrick Chan" NAME="AUTHOR">
<META CONTENT="Code Examples from The Java Developers Almanac 1.4" NAME="DESCRIPTION">
<META CONTENT="Addison-Wesley/Patrick Chan" NAME="OWNER">
<META CONTENT="3/20/02" NAME="revision">
<META CONTENT="no-cache" HTTP-EQUIV="Pragma">
<LINK href="/almanac.css" media="screen" type="text/css" rel="stylesheet">
</HEAD>
<BODY>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
</TABLE>
<br>
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD></TD>
</TR>
<TR>
<TD rowspan="3"><A HREF="/?l=ex"><IMG BORDER="0" ALIGN="BOTTOM" HSPACE="10" SRC="/egs/almanac14a.jpg"></A></TD><TD VALIGN="top">
<h1>The Java Developers Almanac 1.4</h1>
<br>
Order this book from <a href="/cgi-bin/scripts/redirect.pl?l=ex&url=http://www.amazon.com/exec/obidos/ASIN/0201752808/xeo">Amazon</a>.
</TD>
</TR>
<TR>
<TD align="right" valign="bottom">
<FORM method="get" action="/cgi-bin/search/find.pl">
<INPUT size="25" name="words" type="text"><INPUT value="Search" type="submit">
</FORM>
</TD>
</TR>
</TABLE>
<HR color="#6666cc">
<TABLE CELLSPACING="0" CELLPADDING="0" BORDER="0">
<TR>
<TD valign="top"><script type="text/javascript">
<!--
google_ad_client = "pub-6001183370374757";
google_ad_width = 120;
google_ad_height = 600;
google_ad_format = "120x600_as";
google_ad_channel = "4777242811";
google_ad_type = "text_image";
google_color_border = "FFFFFF";
google_color_bg = "FFFFFF";
google_color_link = "6666CC";
google_color_url = "6666CC";
google_color_text = "000000";
//--></script><script src="http://pagead2.googlesyndication.com/pagead/show_ads.js" type="text/javascript"></script></TD><TD> </TD><TD valign="top">
<DIV ALIGN="LEFT">
<A HREF="/">Home</A>
>
<A HREF="../index.html">List of Packages</A>
>
<A HREF="../javax.swing.text/pkg.html">javax.swing.text</A><font color="#666666" class="xsmall-font">
[49 examples]
</font>
>
<B><A HREF="../javax.swing.text/pkg.html#JTextComponent">JTextComponent</A></B><font color="#666666" class="xsmall-font">
[11 examples]
</font>
</DIV><P>
<h3>e974. Using a Position in a JTextComponent</h3>
A position marks a location between two characters in a
<code>JTextComponent</code>. The position attempts to remain between the same
two characters despite edits to the <code>JTextComponent</code>. For example,
if the position is at location 10 and the first character is deleted,
the new location of the position becomes 9.
<P> When text is inserted at the position, a position's bias
determines whether it remains in the same location or is
moved to the end of the new text. By default, <code>createPosition()</code>
returns a position with a right bias, which means inserting text at the
position causes it to move to the end of the inserted text.
There is no way to change the bias at present.
<pre> JTextComponent textComp = new <font color="#0066ff"><i>JTextArea()</i></font>;
Document doc = textComp.getDocument();
Position p = null;
try {
// Create a right-bias Position object
int location = <font color="#0066ff"><i>3</i></font>;
p = doc.createPosition(location);
} catch (BadLocationException e) {
}
// Retrieve the current location of the Position object
int location = p.getOffset();
</pre>
<P><table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td bgcolor="#6666cc" align="center"><font color="#ffffff">
<b>Related Examples</b></font></td>
</tr>
</table>
e968. <a class="eglink" href="GetText.html?l=rel">
Retrieving Text from a JTextComponent
</a>
<br>
e969. <a class="eglink" href="PartialSeg.html?l=rel">
Retrieving All the Text from a JTextComponent Efficiently
</a>
<br>
e970. <a class="eglink" href="EditTextField.html?l=rel">
Modifying Text in a JTextComponent
</a>
<br>
e971. <a class="eglink" href="ConcurReadText.html?l=rel">
Asynchronously Reading the Contents of a Visible JTextComponent
</a>
<br>
e972. <a class="eglink" href="FindWord.html?l=rel">
Finding Word Boundaries in a JTextComponent
</a>
<br>
e973. <a class="eglink" href="GetWrappedLines.html?l=rel">
Retrieving the Visible Lines in a JTextComponent
</a>
<br>
e975. <a class="eglink" href="LimitText.html?l=rel">
Limiting the Capacity of a JTextComponent
</a>
<br>
e976. <a class="eglink" href="DragEnabledTextArea.html?l=rel">
Enabling Text-Dragging on a JTextComponent
</a>
<br>
e977. <a class="eglink" href="ShareDoc.html?l=rel">
Sharing a Document Between JTextComponents
</a>
<br>
e978. <a class="eglink" href="WalkViews.html?l=rel">
Enumerating All the Views in a JTextComponent
</a>
<br>
<table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
<tr>
<td align="left">
<br>
See also:
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#Actions%20and%20Key%20Bindings">
Actions and Key Bindings
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#Caret%20and%20Selection">
Caret and Selection
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#Events">
Events
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#JEditorPane">
JEditorPane
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#JFormattedTextField">
JFormattedTextField
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#JTextArea">
JTextArea
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#JTextField">
JTextField
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#JTextPane">
JTextPane
</a>
<a class="eglink" href="/egs/javax.swing.text/pkg.html?l=rel#Styles">
Styles
</a>
</td>
</tr>
</table>
<br>
<br>
<FONT class="xsmall-font">
© 2002 Addison-Wesley.
</FONT></TD><TD> </TD><TD valign="top"><A href="http://compositesw.com/devzone?ref=javaalmanac"><IMG alt="Click Here" height="600" width="120" border="0" src="/csw_oad_120x600_final.gif"></A></TD>
</TR>
</TABLE>
</BODY>
<HEAD>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<META CONTENT="NO-CACHE" HTTP-EQUIV="PRAGMA">
</HEAD>
</HTML>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -