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<TITLE>Listening for Changes to the Selected File in a JFileChooser Dialog (Java Developers Almanac Example)
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<A HREF="../javax.swing.filechooser/pkg.html">javax.swing.filechooser</A><font color="#666666" class="xsmall-font">
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<B><A HREF="../javax.swing.filechooser/pkg.html#Events">Events</A></B><font color="#666666" class="xsmall-font">
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<h3>e903. Listening for Changes to the Selected File in a JFileChooser Dialog</h3>
A property change event is fired whenever the selected file is
changed. However, the selected file can be null if the selected item
does not match the selection mode of the chooser. For example, if the
selection mode is <code>JFileChooser.FILES_ONLY</code> and a directory is
selected, the fired event will have a new value of null.
<P> Note: <code>SELECTED_FILE_CHANGED_PROPERTY</code> events are fired only
if a single item is selected. In particular, if multiple items are
selected while multiple-selection mode is enabled, this event is
not fired. But if a single item is selected while in
multiple-selection mode, this event is fired.
<P> When in multiple-selection mode,
<code>SELECTED_FILES_CHANGED_PROPERTY</code> events are always fired
regardless of whether a single or multiple files have been selected.
<pre> JFileChooser chooser = new JFileChooser();
// Add listener on chooser to detect changes to selected file
chooser.addPropertyChangeListener(new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent evt) {
if (JFileChooser.SELECTED_FILE_CHANGED_PROPERTY
.equals(evt.getPropertyName())) {
JFileChooser chooser = (JFileChooser)evt.getSource();
File oldFile = (File)evt.getOldValue();
File newFile = (File)evt.getNewValue();
// The selected file should always be the same as newFile
File curFile = chooser.getSelectedFile();
} else if (JFileChooser.SELECTED_FILES_CHANGED_PROPERTY.equals(
evt.getPropertyName())) {
JFileChooser chooser = (JFileChooser)evt.getSource();
File[] oldFiles = (File[])evt.getOldValue();
File[] newFiles = (File[])evt.getNewValue();
// Get list of selected files
// The selected files should always be the same as newFiles
File[] files = chooser.getSelectedFiles();
}
}
}) ;
</pre>
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<b>Related Examples</b></font></td>
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e904. <a class="eglink" href="DirEvent.html?l=rel">
Listening for Changes to the Current Directory in a JFileChooser Dialog
</a>
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e905. <a class="eglink" href="DoneEvent.html?l=rel">
Listening for Approve and Cancel Events in a JFileChooser Dialog
</a>
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See also:
<a class="eglink" href="/egs/javax.swing.filechooser/pkg.html?l=rel#Hidden%20Files">
Hidden Files
</a>
<a class="eglink" href="/egs/javax.swing.filechooser/pkg.html?l=rel#Icons">
Icons
</a>
<a class="eglink" href="/egs/javax.swing.filechooser/pkg.html?l=rel#Layout">
Layout
</a>
<a class="eglink" href="/egs/javax.swing.filechooser/pkg.html?l=rel#Selections">
Selections
</a>
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