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package javax.swing.text;



Interface for Views that have size dependent upon tabs.

Author: Timothy Prinzing,  Scott Violet
See Also:
/**
 * Interface for <code>View</code>s that have size dependent upon tabs.
 *
 * @author  Timothy Prinzing
 * @author  Scott Violet
 * @see TabExpander
 * @see LabelView
 * @see ParagraphView
 */
public interface TabableView {

    
Determines the desired span when using the given
tab expansion implementation.  If a container
calls this method, it will do so prior to the
normal layout which would call getPreferredSpan.
A view implementing this should give the same
result in any subsequent calls to getPreferredSpan
along the axis of tab expansion.

Params:
  • x – the position the view would be located
 at for the purpose of tab expansion >= 0.
  • e – how to expand the tabs when encountered.
Returns:the desired span >= 0
/**
     * Determines the desired span when using the given
     * tab expansion implementation.  If a container
     * calls this method, it will do so prior to the
     * normal layout which would call getPreferredSpan.
     * A view implementing this should give the same
     * result in any subsequent calls to getPreferredSpan
     * along the axis of tab expansion.
     *
     * @param x the position the view would be located
     *  at for the purpose of tab expansion &gt;= 0.
     * @param e how to expand the tabs when encountered.
     * @return the desired span &gt;= 0
     */
    float getTabbedSpan(float x, TabExpander e);

    
Determines the span along the same axis as tab
expansion for a portion of the view.  This is
intended for use by the TabExpander for cases
where the tab expansion involves aligning the
portion of text that doesn't have whitespace
relative to the tab stop.  There is therefore
an assumption that the range given does not
contain tabs.

Params:
  • p0 – the starting location in the text document >= 0
  • p1 – the ending location in the text document >= p0
Returns:the span >= 0
/**
     * Determines the span along the same axis as tab
     * expansion for a portion of the view.  This is
     * intended for use by the TabExpander for cases
     * where the tab expansion involves aligning the
     * portion of text that doesn't have whitespace
     * relative to the tab stop.  There is therefore
     * an assumption that the range given does not
     * contain tabs.
     *
     * @param p0 the starting location in the text document &gt;= 0
     * @param p1 the ending location in the text document &gt;= p0
     * @return the span &gt;= 0
     */
    float getPartialSpan(int p0, int p1);
}