diff options
Diffstat (limited to 'libjava/classpath/java/awt/BorderLayout.java')
| -rw-r--r-- | libjava/classpath/java/awt/BorderLayout.java | 130 |
1 files changed, 120 insertions, 10 deletions
diff --git a/libjava/classpath/java/awt/BorderLayout.java b/libjava/classpath/java/awt/BorderLayout.java index adf2ebf65f6..1b67c01cfcb 100644 --- a/libjava/classpath/java/awt/BorderLayout.java +++ b/libjava/classpath/java/awt/BorderLayout.java @@ -38,6 +38,7 @@ exception statement from your version. */ package java.awt; + /** * This class implements a layout manager that positions components * in certain sectors of the parent container. @@ -229,6 +230,12 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable private int vgap; + // Some constants for use with calcSize(). + private static final int MIN = 0; + private static final int MAX = 1; + private static final int PREF = 2; + + /** * Initializes a new instance of <code>BorderLayout</code> with no * horiztonal or vertical gaps between components. @@ -423,7 +430,7 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable */ public float getLayoutAlignmentX(Container parent) { - return(parent.getAlignmentX()); + return 0.5F; } /** @@ -438,7 +445,7 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable */ public float getLayoutAlignmentY(Container parent) { - return(parent.getAlignmentY()); + return 0.5F; } /** @@ -449,7 +456,7 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable */ public void invalidateLayout(Container parent) { - // FIXME: Implement this properly! + // Nothing to do here. } /** @@ -560,7 +567,8 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable } /** - * FIXME: Document me! + * This is a convenience method to set the bounds on a component. + * If the indicated component is null, nothing is done. */ private void setBounds(Component comp, int x, int y, int w, int h) { @@ -569,12 +577,6 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable comp.setBounds(x, y, w, h); } - // FIXME: Maybe move to top of file. - // Some constants for use with calcSize(). - private static final int MIN = 0; - private static final int MAX = 1; - private static final int PREF = 2; - private Dimension calcCompSize(Component comp, int what) { if (comp == null || !comp.isVisible()) @@ -660,4 +662,112 @@ public class BorderLayout implements LayoutManager2, java.io.Serializable return(new Dimension(width, height)); } } + + /** + * Return the component at the indicated location, or null if no component + * is at that location. The constraints argument must be one of the + * location constants specified by this class. + * @param constraints the location + * @return the component at that location, or null + * @throws IllegalArgumentException if the constraints argument is not + * recognized + * @since 1.5 + */ + public Component getLayoutComponent(Object constraints) + { + if (constraints == CENTER) + return center; + if (constraints == NORTH) + return north; + if (constraints == EAST) + return east; + if (constraints == SOUTH) + return south; + if (constraints == WEST) + return west; + if (constraints == PAGE_START) + return firstLine; + if (constraints == PAGE_END) + return lastLine; + if (constraints == LINE_START) + return firstItem; + if (constraints == LINE_END) + return lastItem; + throw new IllegalArgumentException("constraint " + constraints + + " is not recognized"); + } + + /** + * Return the component at the specified location, which must be one + * of the absolute constants such as CENTER or SOUTH. The container's + * orientation is used to map this location to the correct corresponding + * component, so for instance in a right-to-left container, a request + * for the EAST component could return the LINE_END component. This will + * return null if no component is available at the given location. + * @param container the container whose orientation is used + * @param constraints the absolute location of the component + * @return the component at the location, or null + * @throws IllegalArgumentException if the constraint is not recognized + */ + public Component getLayoutComponent(Container container, Object constraints) + { + ComponentOrientation orient = container.getComponentOrientation(); + if (constraints == CENTER) + return center; + // Note that we don't support vertical layouts. + if (constraints == NORTH) + return north; + if (constraints == SOUTH) + return south; + if (constraints == WEST) + { + // Note that relative layout takes precedence. + if (orient.isLeftToRight()) + return firstItem == null ? west : firstItem; + return lastItem == null ? west : lastItem; + } + if (constraints == EAST) + { + // Note that relative layout takes precedence. + if (orient.isLeftToRight()) + return lastItem == null ? east : lastItem; + return firstItem == null ? east : firstItem; + } + throw new IllegalArgumentException("constraint " + constraints + + " is not recognized"); + } + + /** + * Return the constraint corresponding to a component in this layout. + * If the component is null, or is not in this layout, returns null. + * Otherwise, this will return one of the constraint constants defined + * in this class. + * @param c the component + * @return the constraint, or null + * @since 1.5 + */ + public Object getConstraints(Component c) + { + if (c == null) + return null; + if (c == center) + return CENTER; + if (c == north) + return NORTH; + if (c == east) + return EAST; + if (c == south) + return SOUTH; + if (c == west) + return WEST; + if (c == firstLine) + return PAGE_START; + if (c == lastLine) + return PAGE_END; + if (c == firstItem) + return LINE_START; + if (c == lastItem) + return LINE_END; + return null; + } } |