📄 none.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"><html> <head> <title>Doing Without a Layout Manager (Absolute Positioning) (The Java™ Tutorials > Creating a GUI with JFC/Swing > Laying Out Components Within a Container)</title><style type="text/css"> .FigureCaption { margin-left: 1in; margin-right: 1in; font-family: sans-serif; font-size: smaller; text-align: justify; } #TopBar_bl { background: url(../../images/java_bar_bl.gif) 0 100% no-repeat; width: 100%; height: 60px; } #TopBar_br { background: url(../../images/java_bar_br.gif) 100% 100% no-repeat; width: 100%; height: 60px; } #TopBar_tl { background: url(../../images/java_bar_tl.gif) 0 0 no-repeat; width: 100%; height: 60px; } #TopBar_tr { background: url(../../images/java_bar_tr.gif) 100% 0 no-repeat; width: 100%; height: 60px; } #TopBar { background: #35556B url(../../images/java_bar.gif); margin: 10px 10px 0 10px; height:60px; min-width:700px; color: white; font-family: sans-serif; font-weight: bold; } @media print { #BreadCrumbs, #Download { display: none; } } #TopBar_right { line-height: 14px; float: right; padding-top: 2px; padding-right: 30px; text-align: center; } @media print { #TopBar_right { display: none; } } #TopBar_right a { font-size: 12px; margin: 3px; padding: 0; } #TopBar a:visited, #TopBar a:link { color: white; text-decoration: none; } #TopBar a:hover, #TopBar a:active { background-color: white; color: #35556B; } #BreadCrumbs { padding: 4px 5px 0.5em 0; font-family: sans-serif; float: right; } #BreadCrumbs a { color: blue; } #BreadCrumbs a:visited, #BreadCrumbs a:link { text-decoration: none; } #BreadCrumbs a:hover, #BreadCrumbs a:active { text-decoration: underline; } #PageTitle { margin: 0 5px 0.5em 0; color: #E76F00; font-family: sans-serif; font-weight: bold; font-size: 20px; } .LeftBar_shown { width: 13em; float: left; margin-left: 10px; margin-top: 4px; margin-bottom: 2em; } @media print { .LeftBar_shown { display: none; } } .LeftBar_hidden { display: none; } #Footer { padding-top: 10px; padding-left: 10px; margin-right: 10px; } .NavBit { padding: 4px 5px 0.5em 0; font-family: sans-serif; } @media print { .NavBit { display: none; } } #TagNotes { text-align: right; font-size: smaller; font-family: sans-serif; } @media print { #TagNotes a:visited, #TagNotes a:link { color: #35556B; text-decoration: none; } } #Contents a, .NavBit a, #TagNotes a { color: blue } #TagNotes a:visited, #TagNotes a:link, #Contents a:visited, #Contents a:link, .NavBit a:visited, .NavBit a:link { text-decoration: none; } #TagNotes a:hover, #TagNotes a:active, #Contents a:hover, #Contents a:active, .NavBit a:hover, .NavBit a:active { text-decoration: underline; } #Contents { float: left; font-family: sans-serif; } @media print { #Contents { display: none; } } @media screen { div.PrintHeaders { display: none; } } .linkLESSON, .nolinkLESSON { margin-left: 0.5em; text-indent: -0.5em } .linkAHEAD, .nolinkAHEAD, .linkQUESTIONS, .nolinkQUESTIONS { margin-left: 1.5em; text-indent: -0.5em } .linkBHEAD, .nolinkBHEAD { margin-left: 2.5em; text-indent: -0.5em } .linkCHEAD, .nolinkCHEAD { margin-left: 3.5em; text-indent: -0.5em } .nolinkLESSON, .nolinkAHEAD, .nolinkBHEAD, .nolinkCHEAD, .nolinkQUESTIONS { font-weight: bold; color: #E76F00; } .MainFlow_indented { margin-right: 10px; margin-left: 15em; margin-bottom: 2em; } .MainFlow_wide { margin-right: 10px; margin-left: 10px; margin-bottom: 2em; } @media print { .MainFlow_indented, .MainFlow_wide { padding-top: 0; margin-top: 10px; margin-right: 10px; margin-left: 0; } } h3, h4, h5 { color: #E76F00; font-family: sans-serif; } #ToggleLeft { display: none; } /t</style><script type="text/javascript"> function leftBar() { var nameq = 'tutorial_showLeftBar=' var cookies = document.cookie.split(';'); for (var i = 0; i < cookies.length; i++) { var cookieString = cookies[i]; while (cookieString.charAt(0) == ' ') { cookieString = cookieString.substring(1, cookieString.length); } if (cookieString.indexOf(nameq) == 0) { cookieValue = cookieString.substring(nameq.length, cookieString.length); return cookieValue == 'yes'; } } return true; } function showLeft(b) { var contents = document.getElementById("LeftBar"); var main = document.getElementById("MainFlow"); var toggle = document.getElementById("ToggleLeft"); if (b) { contents.className = "LeftBar_shown"; main.className = "MainFlow_indented"; toggle.innerHTML = "Hide the TOC"; document.cookie = 'tutorial_showLeftBar=yes; path=/'; } else { contents.className = "LeftBar_hidden"; main.className = "MainFlow_wide"; toggle.innerHTML = "Show the TOC"; document.cookie = 'tutorial_showLeftBar=no; path=/'; } } function toggleLeft() { showLeft(document.getElementById("LeftBar").className == "LeftBar_hidden"); document.getElementById("ToggleLeft").blur(); } function load() { showLeft(leftBar()); document.getElementById("ToggleLeft").style.display="inline"; } </script> </head><body onload="load()"> <div id=TopBar> <div id=TopBar_tr> <div id=TopBar_tl> <div id=TopBar_br> <div id=TopBar_bl> <div id=TopBar_right> <a target="_blank" href="http://java.sun.com/javase/6/download.jsp">Download the JDK</a> <br> <a href="../../search.html" target="_blank">Search the Tutorials</a> <br> <a href="javascript:toggleLeft()" id="ToggleLeft">Hide the TOC</a> </div> </div> </div> </div> </div> </div> <div class=PrintHeaders> <b>Trail:</b> Creating a GUI with JFC/Swing <br><b>Lesson:</b> Laying Out Components Within a Container </div> <div id=LeftBar class=LeftBar_shown> <div id=Contents> <div class="linkLESSON"><a href="index.html">Laying Out Components Within a Container</a></div><div class="linkAHEAD"><a href="visual.html">A Visual Guide to Layout Managers</a></div><div class="linkAHEAD"><a href="using.html">Using Layout Managers</a></div><div class="linkAHEAD"><a href="howLayoutWorks.html">How Layout Management Works</a></div><div class="linkAHEAD"><a href="layoutlist.html">How to Use Various Layout Managers</a></div><div class="linkAHEAD"><a href="border.html">How to Use BorderLayout</a></div><div class="linkAHEAD"><a href="box.html">How to Use BoxLayout</a></div><div class="linkAHEAD"><a href="card.html">How to Use CardLayout</a></div><div class="linkAHEAD"><a href="flow.html">How to Use FlowLayout</a></div><div class="linkAHEAD"><a href="gridbag.html">How to Use GridBagLayout</a></div><div class="linkAHEAD"><a href="grid.html">How to Use GridLayout</a></div><div class="linkAHEAD"><a href="group.html">How to Use GroupLayout</a></div><div class="linkBHEAD"><a href="groupExample.html">A GroupLayout Example</a></div><div class="linkAHEAD"><a href="spring.html">How to Use SpringLayout</a></div><div class="linkAHEAD"><a href="custom.html">Creating a Custom Layout Manager</a></div><div class="nolinkAHEAD">Doing Without a Layout Manager (Absolute Positioning)</div><div class="linkAHEAD"><a href="problems.html">Solving Common Layout Problems</a></div></div> </div> <div id=MainFlow class=MainFlow_indented> <span id=BreadCrumbs> <a href=../../index.html target=_top>Home Page</a> > <a href=../index.html target=_top>Creating a GUI with JFC/Swing</a> > <a href=index.html target=_top>Laying Out Components Within a Container</a> </span> <div class=NavBit> <a target=_top href=custom.html>« Previous</a> • <a target=_top href=../TOC.html>Trail</a> • <a target=_top href=problems.html>Next »</a> </div> <div id=PageTitle>Doing Without a Layout Manager (Absolute Positioning)</div> <blockquote>Although it's possible to do without a layout manager,you should use a layout manager if at all possible.A layout manager makes it easier toadjust to look-and-feel-dependent component appearances,to different font sizes,to a container's changing size,and to different locales.Layout managers also can be reused easily by other containersas well as other programs.<p>If a containerholds components whose size isn't affectedby the container's sizeor by font and look-and-feel and language changes,then absolute positioning might make sense.Desktop panes,which contain<a class="TutorialLink" target="_top" href="../components/internalframe.html">internal frames</a>, are in this category.The size and position of internal framesdoesn't depend directly on the desktop pane's size.The programmer determines the initial size and placementof internal frames within the desktop pane,and then the user can move or resize the frames.A layout manager is unnecessary in this situation.<p>Another situation in which absolute positioning might make senseis that of a custom containerthat performs size and position calculationsthat are particular to the container,and perhaps require knowledgeof the container's specialized state.This is the situation with<a class="TutorialLink" target="_top" href="../components/splitpane.html">split panes</a>.<p>Here's a snapshot of a framewhose content pane uses absolute positioning.<p><p><center><IMG SRC="../../figures/uiswing/layout/AbsoluteLayoutDemo.png" WIDTH="300" HEIGHT="125" ALIGN="BOTTOM" ALT="A snapshot of AbsoluteLayoutDemo"></center></p><p>You can<a href="http://java.sun.com/docs/books/tutorialJWS/uiswing/layout/examples/AbsoluteLayoutDemo.jnlp">run AbsoluteLayoutDemo</a>using<a class="TutorialLink" target="_top" href="../../information/javawebstart.html">Java<sup><font size=-2>TM</font></sup> Web Start</a>.Its code is in<a class="SourceLink" target="_blank" href="examples/AbsoluteLayoutDemo.java"><code>AbsoluteLayoutDemo.java</code></a>.The following code snippetshows how the components in the content paneare created and laid out.<blockquote><pre>pane.setLayout(null);JButton b1 = new JButton("one");JButton b2 = new JButton("two");JButton b3 = new JButton("three");pane.add(b1);pane.add(b2);pane.add(b3);Insets insets = pane.getInsets();Dimension size = b1.getPreferredSize();b1.setBounds(25 + insets.left, 5 + insets.top, size.width, size.height);size = b2.getPreferredSize();b2.setBounds(55 + insets.left, 40 + insets.top, size.width, size.height);size = b3.getPreferredSize();b3.setBounds(150 + insets.left, 15 + insets.top, size.width + 50, size.height + 20);...<em>//In the main method:</em>Insets insets = frame.getInsets();frame.setSize(300 + insets.left + insets.right, 125 + insets.top + insets.bottom);</pre></blockquote> </blockquote> <div class=NavBit> <a target=_top href=custom.html>« Previous</a> • <a target=_top href=../TOC.html>Trail</a> • <a target=_top href=problems.html>Next »</a> </div> </div> <div id=Footer><div id=TagNotes> Problems with the examples? Try <a target="_blank" href=../../information/run-examples.html>Compiling and Running the Examples: FAQs</a>. <br> Complaints? Compliments? Suggestions? <a target="_blank" href="http://developer.sun.com/contact/tutorial_feedback.jsp">Give us your feedback</a>.<br><br> <a target="_blank" href="../../information/copyright.html">Copyright</a> 1995-2006 Sun Microsystems, Inc. All rights reserved. <span id=Download></span></div> </div> <div class=PrintHeaders> <b>Previous page:</b> Creating a Custom Layout Manager <br><b>Next page:</b> Solving Common Layout Problems </div> </body></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 + -