Package Summary Overview Summary

### class:JLayeredPane [NONE]
- All Implemented Interfaces: ImageObserver, MenuContainer, Serializable, Accessible Direct Known Subclasses: JDesktopPane
      public class JLayeredPane
      extends JComponent
      implements Accessible
  `JLayeredPane` adds depth to a JFC/Swing container, allowing components to overlap each other when needed. An `Integer` object specifies each component's depth in the container, where higher-numbered components sit "on top" of other components. For task-oriented documentation and examples of using layered panes see How to Use a Layered Pane , a section in The Java Tutorial .
  For convenience, `JLayeredPane` divides the depth-range into several different layers. Putting a component into one of those layers makes it easy to ensure that components overlap properly, without having to worry about specifying numbers for specific depths: DEFAULT_LAYER The standard layer, where most components go. This the bottommost layer. PALETTE_LAYER The palette layer sits over the default layer. Useful for floating toolbars and palettes, so they can be positioned above other components. MODAL_LAYER The layer used for modal dialogs. They will appear on top of any toolbars, palettes, or standard components in the container. POPUP_LAYER The popup layer displays above dialogs. That way, the popup windows associated with combo boxes, tooltips, and other help text will appear above the component, palette, or dialog that generated them. DRAG_LAYER When dragging a component, reassigning it to the drag layer ensures that it is positioned over every other component in the container. When finished dragging, it can be reassigned to its normal layer. The `JLayeredPane` methods `moveToFront(Component)`, `moveToBack(Component)` and `setPosition` can be used to reposition a component within its layer. The `setLayer` method can also be used to change the component's current layer. ## Details `JLayeredPane` manages its list of children like `Container`, but allows for the definition of a several layers within itself. Children in the same layer are managed exactly like the normal `Container` object, with the added feature that when children components overlap, children in higher layers display above the children in lower layers. Each layer is a distinct integer number. The layer attribute can be set on a `Component` by passing an `Integer` object during the add call. For example:
           layeredPane.add(child, JLayeredPane.DEFAULT_LAYER);
       or
           layeredPane.add(child, new Integer(10));
  The layer attribute can also be set on a Component by calling
           layeredPaneParent.setLayer(child, 10)
  on the `JLayeredPane` that is the parent of component. The layer should be set before adding the child to the parent. Higher number layers display above lower number layers. So, using numbers for the layers and letters for individual components, a representative list order would look like this:
             5a, 5b, 5c, 2a, 2b, 2c, 1a
  where the leftmost components are closest to the top of the display. A component can be moved to the top or bottom position within its layer by calling `moveToFront` or `moveToBack`. The position of a component within a layer can also be specified directly. Valid positions range from 0 up to one less than the number of components in that layer. A value of -1 indicates the bottommost position. A value of 0 indicates the topmost position. Unlike layer numbers, higher position values are lower in the display. Note: This sequence (defined by java.awt.Container) is the reverse of the layer numbering sequence. Usually though, you will use `moveToFront`, `moveToBack`, and `setLayer`. Here are some examples using the method add(Component, layer, position): Calling add(5x, 5, -1) results in:
             5a, 5b, 5c, 5x, 2a, 2b, 2c, 1a
  Calling add(5z, 5, 2) results in:
             5a, 5b, 5z, 5c, 5x, 2a, 2b, 2c, 1a
  Calling add(3a, 3, 7) results in:
             5a, 5b, 5z, 5c, 5x, 3a, 2a, 2b, 2c, 1a
Using normal paint/event mechanics results in 1a appearing at the bottom and 5a being above all other components. Note: that these layers are simply a logical construct and LayoutManagers will affect all child components of this container without regard for layer settings. Warning: Swing is not thread safe. For more information see Swing's Threading Policy . 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. As of 1.4, support for long term storage of all JavaBeans™ has been added to the `java.beans` package. Please see `XMLEncoder`. Since: 1.2

### field:DEFAULT_LAYER [NONE]
- #### DEFAULT_LAYER
      public static final Integer DEFAULT_LAYER
Convenience object defining the Default layer. Equivalent to new Integer(0).

### field:PALETTE_LAYER [NONE]
- #### PALETTE_LAYER
      public static final Integer PALETTE_LAYER
Convenience object defining the Palette layer. Equivalent to new Integer(100).

### field:MODAL_LAYER [NONE]
- #### MODAL_LAYER
      public static final Integer MODAL_LAYER
Convenience object defining the Modal layer. Equivalent to new Integer(200).

### field:POPUP_LAYER [NONE]
- #### POPUP_LAYER
      public static final Integer POPUP_LAYER
Convenience object defining the Popup layer. Equivalent to new Integer(300).

### field:DRAG_LAYER [NONE]
- #### DRAG_LAYER
      public static final Integer DRAG_LAYER
Convenience object defining the Drag layer. Equivalent to new Integer(400).

### field:FRAME_CONTENT_LAYER [NONE]
- #### FRAME_CONTENT_LAYER
      public static final Integer FRAME_CONTENT_LAYER
Convenience object defining the Frame Content layer. This layer is normally only use to position the contentPane and menuBar components of JFrame. Equivalent to new Integer(-30000). See Also: `JFrame`

### field:LAYER_PROPERTY [NONE]
- #### LAYER_PROPERTY
      public static final String LAYER_PROPERTY
Bound property See Also: Constant Field Values

### constructor:JLayeredPane() [NONE]
- #### JLayeredPane
      public JLayeredPane()
Create a new JLayeredPane

### method:addImpl(java.awt.Component, java.lang.Object, int) [NONE]
- #### addImpl
      protected void addImpl(Component comp,
                             Object constraints,
                             int index)
Description copied from class: `Container` Adds the specified component to this container at the specified index. This method also notifies the layout manager to add the component to this container's layout using the specified constraints object via the `addLayoutComponent` method. The constraints are defined by the particular layout manager being used. For example, the `BorderLayout` class defines five constraints: `BorderLayout.NORTH`, `BorderLayout.SOUTH`, `BorderLayout.EAST`, `BorderLayout.WEST`, and `BorderLayout.CENTER`. The `GridBagLayout` class requires a `GridBagConstraints` object. Failure to pass the correct type of constraints object results in an `IllegalArgumentException`. If the current layout manager implements `LayoutManager2`, then `LayoutManager2.addLayoutComponent(Component,Object)` is invoked on it. If the current layout manager does not implement `LayoutManager2`, and constraints is a `String`, then `LayoutManager.addLayoutComponent(String,Component)` is invoked on it. If the component is not an ancestor of this container and has a non-null parent, it is removed from its current parent before it is added to this container. This is the method to override if a program needs to track every add request to a container as all other add methods defer to this one. An overriding method should usually include a call to the superclass's version of the method: `super.addImpl(comp, constraints, index)` This method changes layout-related information, and therefore, invalidates the component hierarchy. If the container has already been displayed, the hierarchy must be validated thereafter in order to display the added component. Overrides: `addImpl` in class `Container` Parameters: `comp` - the component to be added `constraints` - an object expressing layout constraints for this component `index` - the position in the container's list at which to insert the component, where `-1` means append to the end See Also: `Container.add(Component)`, `Container.add(Component, int)` , `Container.add(Component, java.lang.Object)` , `Container.invalidate()`, `LayoutManager`, `LayoutManager2`

### method:remove(int) [NONE]
- #### remove
      public void remove(int index)
Remove the indexed component from this pane. This is the absolute index, ignoring layers. Overrides: `remove` in class `Container` Parameters: `index` - an int specifying the component to remove See Also: `getIndexOf(java.awt.Component)`

### method:removeAll() [NONE]
- #### removeAll
      public void removeAll()
Removes all the components from this container. Overrides: `removeAll` in class `Container` Since: 1.5 See Also: `Container.add(java.awt.Component)`, `Container.remove(int)`, `Container.invalidate()`

### method:isOptimizedDrawingEnabled() [NONE]
- #### isOptimizedDrawingEnabled
      public boolean isOptimizedDrawingEnabled()
Returns false if components in the pane can overlap, which makes optimized drawing impossible. Otherwise, returns true. Overrides: `isOptimizedDrawingEnabled` in class `JComponent` Returns: false if components can overlap, else true See Also: `JComponent.isOptimizedDrawingEnabled()`

### method:putLayer(javax.swing.JComponent, int) [NONE]
- #### putLayer
      public static void putLayer(JComponent c,
                                  int layer)
Sets the layer property on a JComponent. This method does not cause any side effects like setLayer() (painting, add/remove, etc). Normally you should use the instance method setLayer(), in order to get the desired side-effects (like repainting). Parameters: `c` - the JComponent to move `layer` - an int specifying the layer to move it to See Also: `setLayer(java.awt.Component, int)`

### method:getLayer(javax.swing.JComponent) [NONE]
- #### getLayer
      public static int getLayer(JComponent c)
Gets the layer property for a JComponent, it does not cause any side effects like setLayer(). (painting, add/remove, etc) Normally you should use the instance method getLayer(). Parameters: `c` - the JComponent to check Returns: an int specifying the component's layer

### method:getLayeredPaneAbove(java.awt.Component) [NONE]
- #### getLayeredPaneAbove
      public static JLayeredPane getLayeredPaneAbove(Component c)
Convenience method that returns the first JLayeredPane which contains the specified component. Note that all JFrames have a JLayeredPane at their root, so any component in a JFrame will have a JLayeredPane parent. Parameters: `c` - the Component to check Returns: the JLayeredPane that contains the component, or null if no JLayeredPane is found in the component hierarchy See Also: `JFrame`, `JRootPane`

### method:setLayer(java.awt.Component, int) [NONE]
- #### setLayer
      public void setLayer(Component c,
                           int layer)
Sets the layer attribute on the specified component, making it the bottommost component in that layer. Should be called before adding to parent. Parameters: `c` - the Component to set the layer for `layer` - an int specifying the layer to set, where lower numbers are closer to the bottom

### method:setLayer(java.awt.Component, int, int) [NONE]
- #### setLayer
      public void setLayer(Component c,
                           int layer,
                           int position)
Sets the layer attribute for the specified component and also sets its position within that layer. Parameters: `c` - the Component to set the layer for `layer` - an int specifying the layer to set, where lower numbers are closer to the bottom `position` - an int specifying the position within the layer, where 0 is the topmost position and -1 is the bottommost position

### method:getLayer(java.awt.Component) [NONE]
- #### getLayer
      public int getLayer(Component c)
Returns the layer attribute for the specified Component. Parameters: `c` - the Component to check Returns: an int specifying the component's current layer

### method:getIndexOf(java.awt.Component) [NONE]
- #### getIndexOf
      public int getIndexOf(Component c)
Returns the index of the specified Component. This is the absolute index, ignoring layers. Index numbers, like position numbers, have the topmost component at index zero. Larger numbers are closer to the bottom. Parameters: `c` - the Component to check Returns: an int specifying the component's index

### method:moveToFront(java.awt.Component) [NONE]
- #### moveToFront
      public void moveToFront(Component c)
Moves the component to the top of the components in its current layer (position 0). Parameters: `c` - the Component to move See Also: `setPosition(Component, int)`

### method:moveToBack(java.awt.Component) [NONE]
- #### moveToBack
      public void moveToBack(Component c)
Moves the component to the bottom of the components in its current layer (position -1). Parameters: `c` - the Component to move See Also: `setPosition(Component, int)`

### method:setPosition(java.awt.Component, int) [NONE]
- #### setPosition
      public void setPosition(Component c,
                              int position)
Moves the component to `position` within its current layer, where 0 is the topmost position within the layer and -1 is the bottommost position. Note: Position numbering is defined by java.awt.Container, and is the opposite of layer numbering. Lower position numbers are closer to the top (0 is topmost), and higher position numbers are closer to the bottom. Parameters: `c` - the Component to move `position` - an int in the range -1..N-1, where N is the number of components in the component's current layer

### method:getPosition(java.awt.Component) [NONE]
- #### getPosition
      public int getPosition(Component c)
Get the relative position of the component within its layer. Parameters: `c` - the Component to check Returns: an int giving the component's position, where 0 is the topmost position and the highest index value = the count count of components at that layer, minus 1 See Also: `getComponentCountInLayer(int)`

### method:highestLayer() [NONE]
- #### highestLayer
      public int highestLayer()
Returns the highest layer value from all current children. Returns 0 if there are no children. Returns: an int indicating the layer of the topmost component in the pane, or zero if there are no children

### method:lowestLayer() [NONE]
- #### lowestLayer
      public int lowestLayer()
Returns the lowest layer value from all current children. Returns 0 if there are no children. Returns: an int indicating the layer of the bottommost component in the pane, or zero if there are no children

### method:getComponentCountInLayer(int) [NONE]
- #### getComponentCountInLayer
      public int getComponentCountInLayer(int layer)
Returns the number of children currently in the specified layer. Parameters: `layer` - an int specifying the layer to check Returns: an int specifying the number of components in that layer

### method:getComponentsInLayer(int) [NONE]
- #### getComponentsInLayer
      public Component[] getComponentsInLayer(int layer)
Returns an array of the components in the specified layer. Parameters: `layer` - an int specifying the layer to check Returns: an array of Components contained in that layer

### method:paint(java.awt.Graphics) [NONE]
- #### paint
      public void paint(Graphics g)
Paints this JLayeredPane within the specified graphics context. Overrides: `paint` in class `JComponent` Parameters: `g` - the Graphics context within which to paint See Also: `JComponent.paintComponent(java.awt.Graphics)`, `JComponent.paintBorder(java.awt.Graphics)`, `JComponent.paintChildren(java.awt.Graphics)`, `JComponent.getComponentGraphics(java.awt.Graphics)`, `JComponent.repaint(long, int, int, int, int)`

### method:getComponentToLayer() [NONE]
- #### getComponentToLayer
      protected Hashtable<Component,Integer> getComponentToLayer()
Returns the hashtable that maps components to layers. Returns: the Hashtable used to map components to their layers

### method:getObjectForLayer(int) [NONE]
- #### getObjectForLayer
      protected Integer getObjectForLayer(int layer)
Returns the Integer object associated with a specified layer. Parameters: `layer` - an int specifying the layer Returns: an Integer object for that layer

### method:insertIndexForLayer(int, int) [NONE]
- #### insertIndexForLayer
      protected int insertIndexForLayer(int layer,
                                        int position)
Primitive method that determines the proper location to insert a new child based on layer and position requests. Parameters: `layer` - an int specifying the layer `position` - an int specifying the position within the layer Returns: an int giving the (absolute) insertion-index See Also: `getIndexOf(java.awt.Component)`

### method:paramString() [NONE]
- #### paramString
      protected String paramString()
Returns a string representation of this JLayeredPane. 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`. Overrides: `paramString` in class `JComponent` Returns: a string representation of this JLayeredPane.

### method:getAccessibleContext() [NONE]
- #### getAccessibleContext
      public AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this JLayeredPane. For layered panes, the AccessibleContext takes the form of an AccessibleJLayeredPane. A new AccessibleJLayeredPane instance is created if necessary. Specified by: `getAccessibleContext` in interface `Accessible` Overrides: `getAccessibleContext` in class `Component` Returns: an AccessibleJLayeredPane that serves as the AccessibleContext of this JLayeredPane