javax.swing.text
Class NavigationFilter
- java.lang.Object
-
- javax.swing.text.NavigationFilter
-
public class NavigationFilter extends Object
NavigationFiltercan 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 theNavigationFilter, assuming theJTextComponenthas a non-nullNavigationFilterset. In this manner theNavigationFiltercan effectively restrict where the cursor can be positioned. SimilarlyDefaultCaretwill call into theNavigationFilterwhen 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.- Since:
- 1.4
- See Also:
-
Caret,DefaultCaret,View
-
-
Nested Class Summary
Nested Classes Modifier and Type Class and Description static classNavigationFilter.FilterBypassUsed as a way to circumvent calling back into the caret to position the cursor.
-
Constructor Summary
Constructors Constructor and Description NavigationFilter()
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method and Description intgetNextVisualPositionFrom(JTextComponent text, int pos, Position.Bias bias, int direction, Position.Bias[] biasRet)Returns the next visual position to place the caret at from an existing position.voidmoveDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias)Invoked prior to the Caret moving the dot.voidsetDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias)Invoked prior to the Caret setting the dot.
-
-
-
Method Detail
setDot
public void setDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias)
Invoked prior to the Caret setting the dot. The default implementation calls directly into theFilterBypasswith the passed in arguments. Subclasses may wish to conditionally call super with a different location, or invoke the necessary method on theFilterBypass- Parameters:
-
fb- FilterBypass that can be used to mutate caret position -
dot- the position >= 0 -
bias- Bias to place the dot at
moveDot
public void moveDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias)
Invoked prior to the Caret moving the dot. The default implementation calls directly into theFilterBypasswith the passed in arguments. Subclasses may wish to conditionally call super with a different location, or invoke the necessary methods on theFilterBypass.- Parameters:
-
fb- FilterBypass that can be used to mutate caret position -
dot- the position >= 0 -
bias- Bias for new location
getNextVisualPositionFrom
public int getNextVisualPositionFrom(JTextComponent text, int pos, Position.Bias bias, int direction, Position.Bias[] biasRet) throws BadLocationException
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.- Parameters:
-
text- JTextComponent containing text -
pos- Position used in determining next position -
bias- Bias used in determining next position -
direction- the direction from the current position that can be thought of as the arrow keys typically found on a keyboard. This will be one of the following values:- SwingConstants.WEST
- SwingConstants.EAST
- SwingConstants.NORTH
- SwingConstants.SOUTH
-
biasRet- Used to return resulting Bias of next position - Returns:
- the location within the model that best represents the next location visual position
- Throws:
-
BadLocationException -
IllegalArgumentException- ifdirectiondoesn't have one of the legal values above
-
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2022, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.
