javax.swing.text: public class: NavigationFilter

javax.swing.text
public class: NavigationFilter [javadoc | source]

java.lang.Object
   javax.swing.text.NavigationFilter

Direct Known Subclasses:
DefaultNavigationFilter

NavigationFilter can be used to restrict where the cursor can be positioned. When the default cursor positioning actions attempt to reposition the cursor they will call into the NavigationFilter, assuming the JTextComponent has a non-null NavigationFilter set. In this manner the NavigationFilter can effectively restrict where the cursor can be positioned. Similarly DefaultCaret will call into the NavigationFilter when the user is changing the selection to further restrict where the cursor can be positioned.

Subclasses can conditionally call into supers implementation to restrict where the cursor can be placed, or call directly into the FilterBypass.

Also see:

javax.swing.text.Caret

javax.swing.text.DefaultCaret

javax.swing.text.View

since: 1.4 -

Nested Class Summary:
abstract public static class	NavigationFilter.FilterBypass	Used as a way to circumvent calling back into the caret to position the cursor. Caret implementations that wish to support a NavigationFilter must provide an implementation that will not callback into the NavigationFilter.

Method from javax.swing.text.NavigationFilter Summary:
getNextVisualPositionFrom, moveDot, setDot

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from javax.swing.text.NavigationFilter Detail:
public int getNextVisualPositionFrom(JTextComponent text, int pos, Bias bias, int direction, Bias[] biasRet) throws BadLocationException { return text.getUI().getNextVisualPositionFrom(text, pos, bias, direction, biasRet); } Returns the next visual position to place the caret at from an existing position. The default implementation simply forwards the method to the root View. Subclasses may wish to further restrict the location based on additional criteria.
public void moveDot(FilterBypass fb, int dot, Bias bias) { fb.moveDot(dot, bias); } Invoked prior to the Caret moving the dot. The default implementation calls directly into the `FilterBypass` with the passed in arguments. Subclasses may wish to conditionally call super with a different location, or invoke the necessary methods on the `FilterBypass`.
public void setDot(FilterBypass fb, int dot, Bias bias) { fb.setDot(dot, bias); } Invoked prior to the Caret setting the dot. The default implementation calls directly into the `FilterBypass` with the passed in arguments. Subclasses may wish to conditionally call super with a different location, or invoke the necessary method on the `FilterBypass`

Method from javax.swing.text.NavigationFilter Detail:

 public int getNextVisualPositionFrom(JTextComponent text,
    int pos,
    Bias bias,
    int direction,
    Bias[] biasRet) throws BadLocationException {
        return text.getUI().getNextVisualPositionFrom(text, pos, bias,
                                                      direction, biasRet);
}

Returns the next visual position to place the caret at from an existing position. The default implementation simply forwards the method to the root View. Subclasses may wish to further restrict the location based on additional criteria.

 public  void moveDot(FilterBypass fb,
    int dot,
    Bias bias) {
        fb.moveDot(dot, bias);
}

FilterBypass

 public  void setDot(FilterBypass fb,
    int dot,
    Bias bias) {
        fb.setDot(dot, bias);
}

FilterBypass