* JTextField is intended to be source-compatible * with java.awt.TextField where it is reasonable to do so. This * component has capabilities not found in the java.awt.TextField * class. The superclass should be consulted for additional capabilities. *
* JTextField has a method to establish the string used as the
* command string for the action event that gets fired. The
* java.awt.TextField used the text of the field as the command
* string for the ActionEvent. JTextField will use the command
* string set with the setActionCommand method if not null,
* otherwise it will use the text of the field as a compatibility with
* java.awt.TextField.
*
* The method setEchoChar and getEchoChar
* are not provided directly to avoid a new implementation of a
* pluggable look-and-feel inadvertently exposing password characters.
* To provide password-like services a separate class JPasswordField
* extends JTextField to provide this service with an independently
* pluggable look-and-feel.
*
* The java.awt.TextField could be monitored for changes by adding * a TextListener for TextEvent's. In the JTextComponent based * components, changes are broadcasted from the model via a * DocumentEvent to DocumentListeners. The DocumentEvent gives * the location of the change and the kind of change if desired. * The code fragment might look something like: *
* DocumentListener myListener = ??;
* JTextField myArea = ??;
* myArea.getDocument().addDocumentListener(myListener);
*
* The horizontal alignment of JTextField can be set to be left
* justified, leading justified, centered, right justified or trailing justified.
* Right/trailing justification is useful if the required size
* of the field text is smaller than the size allocated to it.
* This is determined by the setHorizontalAlignment
* and getHorizontalAlignment methods. The default
* is to be leading justified.
*
* For the keyboard keys used by this component in the standard Look and * Feel (L&F) renditions, see the * JTextField key assignments. *
* How the text field consumes VK_ENTER events depends * on whether the text field has any action listeners. * If so, then VK_ENTER results in the listeners * getting an ActionEvent, * and the VK_ENTER event is consumed. * This is compatible with how AWT text fields handle VK_ENTER events. * If the text field has no action listeners, then as of v 1.3 the VK_ENTER * event is not consumed. Instead, the bindings of ancestor components * are processed, which enables the default button feature of * JFC/Swing to work. *
* Customized fields can easily be created by extending the model and * changing the default model provided. For example, the following piece * of code will create a field that holds only upper case characters. It * will work even if text is pasted into from the clipboard or it is altered via * programmatic changes. *
public class UpperCaseField extends JTextField {
public UpperCaseField(int cols) {
super(cols);
}
protected Document createDefaultModel() {
return new UpperCaseDocument();
}
static class UpperCaseDocument extends PlainDocument {
public void insertString(int offs, String str, AttributeSet a)
throws BadLocationException {
if (str == null) {
return;
}
char[] upper = str.toCharArray();
for (int i = 0; i < upper.length; i++) {
upper[i] = Character.toUpperCase(upper[i]);
}
super.insertString(offs, new String(upper), a);
}
}
}
*
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is appropriate
* for short term storage or RMI between applications running the same
* version of Swing. A future release of Swing will provide support for
* long term persistence.
*
* @beaninfo
* attribute: isContainer false
* description: A component which allows for the editing of a single line of text.
*
* @author Timothy Prinzing
* @version 1.72 04/06/00
* @see #setActionCommand
* @see JPasswordField
* @see #addActionListener
*/
public class JTextField extends JTextComponent implements SwingConstants {
/**
* Constructs a new TextField. A default model is created, the initial
* string is null, and the number of columns is set to 0.
*/
public JTextField() {
this(null, null, 0);
}
/**
* Constructs a new TextField initialized with the specified text.
* A default model is created and the number of columns is 0.
*
* @param text the text to be displayed, or null
*/
public JTextField(String text) {
this(null, text, 0);
}
/**
* Constructs a new empty TextField with the specified number of columns.
* A default model is created and the initial string is set to null.
*
* @param columns the number of columns to use to calculate
* the preferred width. If columns is set to zero, the
* preferred width will be whatever naturally results from
* the component implementation.
*/
public JTextField(int columns) {
this(null, null, columns);
}
/**
* Constructs a new TextField initialized with the specified text
* and columns. A default model is created.
*
* @param text the text to be displayed, or null
* @param columns the number of columns to use to calculate
* the preferred width. If columns is set to zero, the
* preferred width will be whatever naturally results from
* the component implementation.
*/
public JTextField(String text, int columns) {
this(null, text, columns);
}
/**
* Constructs a new JTextField that uses the given text storage
* model and the given number of columns. This is the constructor
* through which the other constructors feed. If the document is null,
* a default model is created.
*
* @param doc the text storage to use. If this is null, a default
* will be provided by calling the createDefaultModel method.
* @param text the initial string to display, or null
* @param columns the number of columns to use to calculate
* the preferred width >= 0. If columns is set to zero, the
* preferred width will be whatever naturally results from
* the component implementation.
* @exception IllegalArgumentException if columns < 0
*/
public JTextField(Document doc, String text, int columns) {
if (columns < 0) {
throw new IllegalArgumentException("columns less than zero.");
}
visibility = new DefaultBoundedRangeModel();
visibility.addChangeListener(new ScrollRepainter());
this.columns = columns;
if (doc == null) {
doc = createDefaultModel();
}
setDocument(doc);
if (text != null) {
setText(text);
}
}
/**
* Gets the class ID for a UI.
*
* @return the ID ("TextFieldUI")
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
*/
public String getUIClassID() {
return uiClassID;
}
/**
* Calls to revalidate that come from within the textfield itself will
* be handled by validating the textfield, unless the receiver
* is contained within a JViewport, in which case this returns false.
*
* @see JComponent#revalidate
* @see JComponent#isValidateRoot
*/
public boolean isValidateRoot() {
Component parent = getParent();
if (parent instanceof JViewport) {
return false;
}
return true;
}
/**
* Returns the horizontal alignment of the text.
* Valid keys: JTextField.LEFT, JTextField.CENTER, JTextField.RIGHT,
* JTextField.LEADING and JTextField.TRAILING
*
* @return the alignment
*/
public int getHorizontalAlignment() {
return horizontalAlignment;
}
/**
* Sets the horizontal alignment of the text.
* Valid keys: JTextField.LEFT, JTextField.CENTER, JTextField.RIGHT,
* JTextField.LEADING (the default) and JTextField.TRAILING.
* invalidate() and repaint() are called when the alignment is set,
* and a PropertyChange event ("horizontalAlignment") is fired.
*
* @param alignment the alignment
* @exception IllegalArgumentException if the alignment
* specified is not a valid key.
* @beaninfo
* preferred: true
* bound: true
* description: Set the field alignment to LEFT, CENTER, RIGHT,
* LEADING (the default) or TRAILING
* enum: LEFT JTextField.LEFT CENTER JTextField.CENTER RIGHT JTextField.RIGHT
* LEADING JTextField.LEADING TRAILING JTextField.TRAILING
*/
public void setHorizontalAlignment(int alignment) {
if (alignment == horizontalAlignment) return;
int oldValue = horizontalAlignment;
if ((alignment == LEFT) || (alignment == CENTER) ||
(alignment == RIGHT)|| (alignment == LEADING) ||
(alignment == TRAILING)) {
horizontalAlignment = alignment;
} else {
throw new IllegalArgumentException("horizontalAlignment");
}
firePropertyChange("horizontalAlignment", oldValue, horizontalAlignment);
invalidate();
repaint();
}
/**
* Creates the default implementation of the model
* to be used at construction if one isn't explicitly
* given. An instance of PlainDocument is returned.
*
* @return the default model implementation
*/
protected Document createDefaultModel() {
return new PlainDocument();
}
/**
* Returns the number of columns in this TextField.
*
* @return the number of columns >= 0
*/
public int getColumns() {
return columns;
}
/**
* Sets the number of columns in this TextField, and then invalidate
* the layout.
*
* @param columns the number of columns >= 0
* @exception IllegalArgumentException if columns is less than 0
* @beaninfo
* description: the number of columns preferred for display
*/
public void setColumns(int columns) {
int oldVal = this.columns;
if (columns < 0) {
throw new IllegalArgumentException("columns less than zero.");
}
if (columns != oldVal) {
this.columns = columns;
invalidate();
}
}
/**
* Gets the column width.
* The meaning of what a column is can be considered a fairly weak
* notion for some fonts. This method is used to define the width
* of a column. By default this is defined to be the width of the
* character m for the font used. This method can be
* redefined to be some alternative amount
*
* @return the column width >= 1
*/
protected int getColumnWidth() {
if (columnWidth == 0) {
FontMetrics metrics = getFontMetrics(getFont());
columnWidth = metrics.charWidth('m');
}
return columnWidth;
}
/**
* Returns the preferred size Dimensions needed for this
* TextField. If a non-zero number of columns has been
* set, the width is set to the columns multiplied by
* the column width.
*
* @return the dimensions
*/
public Dimension getPreferredSize() {
synchronized (getTreeLock()) {
Dimension size = super.getPreferredSize();
if (columns != 0) {
size.width = columns * getColumnWidth();
}
return size;
}
}
/**
* Sets the current font. This removes cached row height and column
* width so the new font will be reflected. revalidate() is called
* after setting the font.
*
* @param f the new font
*/
public void setFont(Font f) {
super.setFont(f);
columnWidth = 0;
}
/**
* Adds the specified action listener to receive
* action events from this textfield.
*
* @param l the action listener
*/
public synchronized void addActionListener(ActionListener l) {
listenerList.add(ActionListener.class, l);
}
/**
* Removes the specified action listener so that it no longer
* receives action events from this textfield.
*
* @param l the action listener
*/
public synchronized void removeActionListener(ActionListener l) {
if ((l != null) && (getAction() == l)) {
setAction(null);
} else {
listenerList.remove(ActionListener.class, l);
}
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type. The event instance
* is lazily created using the parameters passed into
* the fire method. The listener list is processed in last to
* first order.
* @see EventListenerList
*/
protected void fireActionPerformed() {
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
ActionEvent e = new ActionEvent(this, ActionEvent.ACTION_PERFORMED,
(command != null) ? command : getText());
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==ActionListener.class) {
((ActionListener)listeners[i+1]).actionPerformed(e);
}
}
}
/**
* Sets the command string used for action events.
*
* @param command the command string
*/
public void setActionCommand(String command) {
this.command = command;
}
private Action action;
private PropertyChangeListener actionPropertyChangeListener;
/**
* Sets the Action for the ActionEvent source. The new Action replaces
* any previously set Action but does not affect ActionListeners
* independantly added with addActionListener(). If the Action is already
* a registered ActionListener for the ActionEvent source, it is not re-registered.
*
* A side-effect of setting the Action is that the ActionEvent source's properties
* are immediately set from the values in the Action (performed by the method
* configurePropertiesFromAction()) and subsequently updated as the Action's
* properties change (via a PropertyChangeListener created by the method
* createActionPropertyChangeListener().
*
* @param a the Action for the JTextField, or null.
* @since 1.3
* @see Action
* @see #getAction
* @see #configurePropertiesFromAction
* @see #createActionPropertyChangeListener
* @beaninfo
* bound: true
* attribute: visualUpdate true
* description: the Action instance connected with this ActionEvent source
*/
public void setAction(Action a) {
Action oldValue = getAction();
if (action==null || !action.equals(a)) {
action = a;
if (oldValue!=null) {
removeActionListener(oldValue);
oldValue.removePropertyChangeListener(actionPropertyChangeListener);
actionPropertyChangeListener = null;
}
configurePropertiesFromAction(action);
if (action!=null) {
// Don't add if it is already a listener
if (!isListener(ActionListener.class, action)) {
addActionListener(action);
}
// Reverse linkage:
actionPropertyChangeListener = createActionPropertyChangeListener(action);
action.addPropertyChangeListener(actionPropertyChangeListener);
}
firePropertyChange("action", oldValue, action);
revalidate();
repaint();
}
}
private boolean isListener(Class c, ActionListener a) {
boolean isListener = false;
Object[] listeners = listenerList.getListenerList();
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==c && listeners[i+1]==a) {
isListener=true;
}
}
return isListener;
}
/**
* Returns the currently set Action for this ActionEvent source,
* or null if no Action is set.
*
* @return the Action for this ActionEvent source, or null.
* @since 1.3
* @see Action
* @see #setAction
*/
public Action getAction() {
return action;
}
/**
* Factory method which sets the ActionEvent source's properties
* according to values from the Action instance. The properties
* which are set may differ for subclasses.
* By default, the properties which get set are
* Enabled and ToolTipText.
*
* @param a the Action from which to get the properties, or null
* @since 1.3
* @see Action
* @see #setAction
*/
protected void configurePropertiesFromAction(Action a) {
setEnabled((a!=null?a.isEnabled():true));
setToolTipText((a!=null?(String)a.getValue(Action.SHORT_DESCRIPTION):null));
}
/**
* Factory method which creates the PropertyChangeListener
* used to update the ActionEvent source as properties change on
* its Action instance. Subclasses may override this in order
* to provide their own PropertyChangeListener if the set of
* properties which should be kept up to date differs from the
* default properties (Text, Enabled, ToolTipText).
*
* Note that PropertyChangeListeners should avoid holding
* strong references to the ActionEvent source, as this may hinder
* garbage collection of the ActionEvent source and all components
* in its containment hierarchy.
*
* @since 1.3
* @see Action
* @see #setAction
*/
protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
return new AbstractActionPropertyChangeListener(this, a) {
public void propertyChange(PropertyChangeEvent e) {
String propertyName = e.getPropertyName();
JTextField textField = (JTextField)getTarget();
if (textField == null) { //WeakRef GC'ed in 1.2
Action action = (Action)e.getSource();
action.removePropertyChangeListener(this);
} else {
if (e.getPropertyName().equals(Action.SHORT_DESCRIPTION)) {
String text = (String) e.getNewValue();
textField.setToolTipText(text);
} else if (propertyName.equals("enabled")) {
Boolean enabledState = (Boolean) e.getNewValue();
textField.setEnabled(enabledState.booleanValue());
textField.repaint();
}
}
}
};
}
/**
* Fetches the command list for the editor. This is
* the list of commands supported by the plugged-in UI
* augmented by the collection of commands that the
* editor itself supports. These are useful for binding
* to events, such as in a keymap.
*
* @return the command list
*/
public Action[] getActions() {
return TextAction.augmentList(super.getActions(), defaultActions);
}
/**
* Processes action events occurring on this textfield by
* dispatching them to any registered ActionListener objects.
* This is normally called by the controller registered with
* textfield.
*/
public void postActionEvent() {
fireActionPerformed();
}
// --- Scrolling support -----------------------------------
/**
* Gets the visibility of the text field. This can
* be adjusted to change the location of the visible
* area if the size of the field is greater than
* the area that was allocated to the field.
*
* The fields look-and-feel implementation manages
* the values of the minimum, maximum, and extent
* properties on the BoundedRangeModel.
*
* @return the visibility
* @see BoundedRangeModel
*/
public BoundedRangeModel getHorizontalVisibility() {
return visibility;
}
/**
* Gets the scroll offset.
*
* @return the offset >= 0
*/
public int getScrollOffset() {
return visibility.getValue();
}
/**
* Sets the scroll offset.
*
* @param scrollOffset the offset >= 0
*/
public void setScrollOffset(int scrollOffset) {
visibility.setValue(scrollOffset);
}
/**
* Scrolls the field left or right.
*
* @param r the region to scroll
*/
public void scrollRectToVisible(Rectangle r) {
// convert to coordinate system of the bounded range
int x = r.x + visibility.getValue();
if (x < visibility.getValue()) {
// Scroll to the left
visibility.setValue(x - 2);
} else if(x > visibility.getValue() + visibility.getExtent()) {
// Scroll to the right
visibility.setValue(x - visibility.getExtent() + 2);
}
}
/**
* Returns true if the receiver has an ActionListener installed.
*/
boolean hasActionListener() {
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==ActionListener.class) {
return true;
}
}
return false;
}
// --- variables -------------------------------------------
/**
* Name of the action to send notification that the
* contents of the field have been accepted. Typically
* this is bound to a carriage-return.
*/
public static final String notifyAction = "notify-field-accept";
private BoundedRangeModel visibility;
private int horizontalAlignment = LEADING;
private int columns;
private int columnWidth;
private String command;
private static final Action[] defaultActions = {
new NotifyAction()
};
/**
* @see #getUIClassID
* @see #readObject
*/
private static final String uiClassID = "TextFieldUI";
// --- Action implementations -----------------------------------
static class NotifyAction extends TextAction {
NotifyAction() {
super(notifyAction);
}
public void actionPerformed(ActionEvent e) {
JTextComponent target = getFocusedComponent();
if (target instanceof JTextField) {
JTextField field = (JTextField) target;
field.postActionEvent();
}
}
public boolean isEnabled() {
JTextComponent target = getFocusedComponent();
if (target instanceof JTextField) {
return ((JTextField)target).hasActionListener();
}
return false;
}
}
class ScrollRepainter implements ChangeListener {
public void stateChanged(ChangeEvent e) {
repaint();
}
}
/**
* See readObject() and writeObject() in JComponent for more
* information about serialization in Swing.
*/
private void writeObject(ObjectOutputStream s) throws IOException {
s.defaultWriteObject();
if ((ui != null) && (getUIClassID().equals(uiClassID))) {
ui.installUI(this);
}
}
/**
* Returns a string representation of this JTextField. This method
* is intended to be used only for debugging purposes, and the
* content and format of the returned string may vary between
* implementations. The returned string may be empty but may not
* be null.
*
* @return a string representation of this JTextField.
*/
protected String paramString() {
String horizontalAlignmentString;
if (horizontalAlignment == LEFT) {
horizontalAlignmentString = "LEFT";
} else if (horizontalAlignment == CENTER) {
horizontalAlignmentString = "CENTER";
} else if (horizontalAlignment == RIGHT) {
horizontalAlignmentString = "RIGHT";
} else if (horizontalAlignment == LEADING) {
horizontalAlignmentString = "LEADING";
} else if (horizontalAlignment == TRAILING) {
horizontalAlignmentString = "TRAILING";
} else horizontalAlignmentString = "";
String commandString = (command != null ?
command : "");
return super.paramString() +
",columns=" + columns +
",columnWidth=" + columnWidth +
",command=" + commandString +
",horizontalAlignment=" + horizontalAlignmentString;
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this JTextField.
* For JTextFields, the AccessibleContext takes the form of an
* AccessibleJTextField.
* A new AccessibleJTextField instance is created if necessary.
*
* @return an AccessibleJTextField that serves as the
* AccessibleContext of this JTextField
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJTextField();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* JTextField class. It provides an implementation of the
* Java Accessibility API appropriate to text field user-interface
* elements.
*
* Warning: * Serialized objects of this class will not be compatible with * future Swing releases. The current serialization support is appropriate * for short term storage or RMI between applications running the same * version of Swing. A future release of Swing will provide support for * long term persistence. */ protected class AccessibleJTextField extends AccessibleJTextComponent { /** * Gets the state set of this object. * * @return an instance of AccessibleStateSet describing the states * of the object * @see AccessibleState */ public AccessibleStateSet getAccessibleStateSet() { AccessibleStateSet states = super.getAccessibleStateSet(); states.add(AccessibleState.SINGLE_LINE); return states; } } }