Abstract:
An apparatus for finding objects in a computer including a display and a pointing device with which a user drags a pointer on the display, having: an input that receives an input signal to indicate a drag operation; memory that stores a plurality of objects including enclosures in the memory, wherein enclosures comprise objects which may enclose other objects; window opening logic, coupled with the display, that draws windows on the display corresponding to opened enclosures, wherein a window for an opened enclosure includes identifiers within the window corresponding to objects enclosed by the opened enclosure; and, temporary window logic, coupled to the display and the pointing device, that opens a temporary window for the particular enclosure display identifiers within the temporary window corresponding to objects enclosed by the particular enclosure, in response to a drag during a drag operation of the pointer over an identifier corresponding to a particular enclosure.

Description:
This application is a continuation application of U.S. patent application Ser. No. 09/964,723, filed Sep. 25, 2001 now U.S. Pat. No. 6,928,621, which is a continuation application of U.S. patent application Ser. No. 09/565,912, filed May 5, 2000 (now issued as U.S. Pat. No. 6,307,545), which is a continuation application of U.S. patent application Ser. No. 08/889,719, filed Jul. 8, 1997 (now issued as U.S. Pat. No. 6,061,061), which is a continuation application of U.S. patent application Ser. No. 08/482,186, filed Jun. 7, 1995 (now issued as U.S. Pat. No. 5,680,562), which is a continuation application of U.S. patent application Ser. No. 08/076,253, filed Jun. 11, 1993 (now issued as U.S. Pat. No. 5,583,984). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to computer systems with graphical user interfaces, such as window based systems; and more particularly to techniques for finding, moving, and copying objects in such systems. 
     2. Description of the Related Art 
     Graphical user interfaces on computer systems are gaining widespread use. Typical systems include the Macintosh Finder™ environment in Macintosh computers provided by Apple Computer, Inc., of Cupertino, Calif., the Windows environment provided by Microsoft Corporation of Redmond, Wash., and the New Wave™ environment provided by Hewlett-Packard of Palo Alto, Calif. In such systems, a workspace on the display system is set up with a desktop metaphor. Within the desktop, there are icons displayed which correspond to objects stored in memory. Many icons represent enclosures that enclose other objects. Opening the enclosure results in display of a window that encloses related icons. 
     These systems provide the ability to move an object from an enclosure represented by an icon within one window to an enclosure represented by another window or icon, or to copy an object represented by an icon within one window into an enclosure represented by another window or icon. These operations involve first setting up a destination window. The problem of setting up the destination window may be quite complicated, when the system involves a complex hierarchy of enclosures. Further, the process of setting up the destination window may clutter the desktop with a number of windows, obscuring the windows actually in use. 
     After setting up the destination window, the cursor is moved to an icon representing the object to be placed in the destination window by the move or copy operation. A drag operation is then executed to move the icon into the destination window. The drag operation typically involves placing the cursor over the icon subject of the drag operation, depressing the mouse button, and while the mouse button remains depressed, moving the cursor into the destination window. The mouse button is released when the cursor is over the destination window. The operating system responds to this manipulation of the graphical interface by either moving the object into the destination window if both the object and the destination are stored on the same disk, or copying the object into the destination window if the destination is on a different disk than the object. 
     Finally, after the drag operation, the user must clean up the desktop by closing the unneeded windows that were opened during the process of setting up the destination window. 
     As can be appreciated, this process is quite cumbersome when the destination window is deep in a hierarchy. Also, the problem of setting up the destination window makes initiation of a drag operation problematic. It would be desirable to be able to browse through the storage system hierarchy after the drag operation has begun. 
     SUMMARY OF THE INVENTION 
     The present invention provides a new behavior in a graphical user interface which allows the user to open and close enclosure windows, while dragging an object. When the user pauses, gestures, or rolls over a hot spot on top of an identifier representing a closed enclosure, a temporary window for the closed enclosure is “sprung open” to allow the user to browse inside the enclosure and possibly open another enclosure contained within the sprung open window. This process can be carried on throughout a deep hierarchy of windows as the user browses for a destination for the drag operation. 
     The user may close sprung open windows by simply moving the cursor out of the sprung open window, or by making some other indication with the pointing device, as suits the needs of a particular design. 
     Further, if an enclosure to be sprung open was previously open on the desktop, the previously opened window may zoom over to the current cursor position, and then return to its original position when the user moves the cursor out of the window. 
     Accordingly, the present invention can be characterized as an apparatus for finding or browsing among enclosures in a computer system which includes a display, a memory, and a pointing device with which the user drags a pointer (cursor) on the display. The apparatus includes a storage system that stores a plurality of objects which include enclosures in the memory. The enclosures comprise objects which may enclose other objects, and when opened, are represented by a window on the desktop. The system includes window management software that draws windows on the display corresponding to opened enclosures. Also, a mouse with a mouse button, or other input device is included which supplies a signal to indicate a drag operation. The spring loaded enclosures are managed with software responsive to a drag during a drag operation of the pointer over an identifier (textual or graphical) corresponding to a particular enclosure for opening a temporary window for the particular enclosure to display icons within the temporary window that correspond to the objects enclosed by the particular enclosure. Further, the spring-loaded enclosure management software is responsive to a drag during the drag operation of the pointer outside the temporary window for closing the temporary window. 
     By releasing the mouse button or otherwise indicating an end of the drag operation, the user signals software for placing the particular object subject of the drag into the particular enclosure which has been sprung open during the drag. 
     The spring-loaded enclosure management software further determines whether the display includes an existing window opened for the particular enclosure during the drag operation to open a temporary window, and, if so, then removing the existing window from the display and drawing the temporary window on the display centered around the cursor, or otherwise associated with the position of the identifier corresponding to the particular enclosure. Also, in one aspect, the invention provides for graphically indicating on the display a zoom of the existing window over to the location of the temporary window. When the temporary window is closed, the existing window may be re-drawn on the display at its original position. 
     The decision to open a temporary window during a drag operation may be conditioned on actions by the user of the pointing device, such as pausing over the identifier for the particular enclosure, or making some other gesture. For instance, the identifier for enclosures that may be opened may include a hot region or temporary window area. Moving the cursor over the temporary window area of the identifier will cause the enclosure to be sprung open. Alternatively, moving the cursor over an identifier of an enclosure may cause display of a split selector graphic. Moving the cursor to a particular side of the split selector graphic will cause the enclosure to spring open; while moving to the other side of the split selector graphic will cause the split selector graphic to be removed from the screen. 
     Thus, using the spring-loaded enclosure mechanism of the present invention, the user of a graphical user interface is free to browse through enclosures while dragging, rather than being forced to set up the source and destination before the drag begins. This greatly increases the ease of use of the graphical user interface. 
     Other aspects and advantages of the present invention can be seen upon review of the figures, the detailed description, and the claims which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a schematic diagram of a computer system implementing the spring-loaded enclosure management of the present invention. 
         FIGS. 2A-2F  illustrate a drag operation with spring-loaded enclosures according to the present invention. 
         FIGS. 3A-3E  illustrate alternative drag sequences using spring-loaded enclosures according to the present invention. 
         FIG. 4  is a block diagram of functional components of the user interface control system according to the present invention. 
         FIG. 5  is a schematic diagram of data structures used by the system of  FIG. 4 . 
         FIGS. 6-13  provide flow charts for the operation of the system of  FIG. 4 . 
         FIGS. 14A and 14B  illustrate an alternative technique for indicating a wish to open a spring-loaded enclosure. 
         FIGS. 15A and 15B  illustrate another alternative technique for indicating a wish to open a spring-loaded enclosure. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A detailed description of a preferred embodiment of the present invention is provided with respect to the figures.  FIG. 1  provides a system overview.  FIGS. 2A-2D  and  3 A- 3 E illustrate the operation of the graphical user interface using spring-loaded enclosures.  FIGS. 4-13  illustrate an implementation of the control software for a system executing the present invention.  FIGS. 14A-14B  and  15 A- 15 B illustrate alternatives for opening spring-loaded enclosures. 
     I. System Overview ( FIGS. 1 ,  2 A- 2 F, and  3 A- 3 E) 
       FIG. 1  illustrates a computer system implementing the spring-loaded enclosure feature of the present invention. The computer system includes a host CPU  10  coupled to a system bus  11 . The system includes a keyboard  12 , a mouse  13  including a mouse button, or other pointing device, and a non-volatile memory  14 , such as a hard disk, floppy disk, non-volatile integrated circuit memory systems, or the like. Similarly, instruction memory  15  and working memory  16  are coupled to the bus  11 . The instruction memory  15  stores spring-loaded enclosure management software and window management software, among other software needed for operation of the system. The working memory  16  is used to maintain a list of sprung open enclosures, and a window list or other tables needed by the software in the instruction memory  15 . 
     Finally, the system includes a display controller  17  which includes video memory. The display controller  17  drives a display  18  such as a CRT video monitor, LCD flat panel display, or the like. The display system  18  has a screen, generally  19 . On the screen  19 , a workspace  20  is displayed. The workspace  20  is implemented with a desktop metaphor in the Macintosh type systems. Within the desktop  20 , a plurality of identifiers may be displayed, such as the identifier  21  representing a hard disk drive, the identifier  22  representing a floppy disk, and other identifiers not shown which represent files, applications, control panels, or enclosures which enclose other objects. Also on the desktop  20 , a plurality of windows, such as windows  23 ,  24 , and  25  may be opened. The windows  23 ,  24 , and  25  enclosed identifiers, such as identifiers  26  and  27  in window  23 , identifiers  28 ,  29 , and  30  in window  24 , and identifier  31  in window  25 . 
     In the figure, the identifiers are shown as graphical elements, or icons. Alternative identifiers may be textual elements, such as the name of the corresponding object. The behaviors described herein may be applied to both textual and graphical elements, as may occur in windows opened in a view by name mode or a view by icon mode in Macintosh computers. 
     In the illustration of  FIG. 1 , the desktop  20  is somewhat smaller than the screen  19 . Alternative systems may extend the desktop metaphor to the entire area of the screen  19 . 
     The spring-loaded enclosure management software and window management software in the instruction memory  15  of the system are used to open and close windows, and to maintain records concerning the open and closed windows, and their positions within the desktop  20 , the location of icons within the windows or on the desktop  20 , and the like. During a drag operation, the spring-loaded enclosure management software in the instruction memory  15  is operable to create temporary windows so that the user may browse during the drag operation as described above. 
     Examples of the operation of the spring-loaded enclosures are provided with reference to  FIGS. 2A-2F  and  3 A- 3 E. In these diagrams, the same windows  23 ,  24 , and  25  of  FIG. 1  are used as a base for ease of understanding. The “star” identifier  30  in window  24  will be the particular object subject of the drag operation in the examples described. 
       FIGS. 2A-2F  illustrate a basic drag operations using spring-loaded enclosures. In  FIG. 2A , the identifier  30  in window  24  is selected for a drag operation by moving the cursor  50  over the icon  30 , depressing the mouse button and dragging the cursor along a path  51  while holding the mouse button down. The user pauses the cursor over identifier and causes a temporary window  52 , shown in  FIG. 2B , to open substantially centered over the cursor, and thus over identifier  27 . Because the temporary window  52  is slightly too wide to open precisely centered over the cursor  27 , it is redrawn within the desktop area as close as possible to the preferred location centered over the cursor. During the drag operation, the cursor carries an altered view  53  (e.g., an outline) of the star identifier  30  and is displayed within the temporary window  52 . The drag operation continues along path  54  over identifier  55  within the temporary window  52 . By pausing over the identifier  55 , a temporary window  56 , as shown in FIG.  2 C, is opened, centered over the identifier  55 . The altered view  53  of the identifier and the cursor now reside within the temporary window  56 . The user then completes the drag operation to point  57  by releasing the mouse button. This results in placing the identifier  30  within the temporary window  56 , as shown in  FIG. 2D . Also, window  52  closes on mouse up, because it is not the destination. The identifier  30  is removed from window  24  if the temporary window  56  resides on the same disk as temporary window  24 . Otherwise, the icon  30  is copied and will remain in both enclosures. 
     As shown in  FIG. 2D , the temporary window  56  becomes a regular window on the display, as indicated by removal of the hatching across the top of the window  56 . In implementation, temporary windows may be displayed in the same manner as other windows, or marked somehow as temporary. Also, at the end of the drag operation, all of the temporary windows, other than the destination window, are removed from the display. Thus, the temporary window  52  is no longer displayed within the desktop as shown in  FIG. 2D . 
       FIGS. 2E and 2F  illustrate an alternative behavior. In this aspect, the temporary windows, such as window  52 , do not automatically close after termination of the drag operation which leaves the star icon  30  in window  56 . Rather, the temporary windows are closed in response to movement of the pointer after termination of the drag outside of the particular temporary window. Thus, as illustrated in  FIG. 2E , if after termination of the drag, the user moves the cursor along path  58  outside temporary window  56 , then the temporary window  56  will be removed from the screen. Temporary window  52  as illustrated in  FIG. 2F  remains on screen because the cursor remains Within that temporary window. If the user then moves the cursor along path  59  outside temporary window  52 , then temporary window  52  will be removed, returning the screen to the configuration of  FIG. 2A , except with the star icon  30  moved. The user, according to this aspect, may choose to maintain a temporary window open by clicking the mouse button while the cursor lies within the temporary window. Thus, if after completion of the drag operation in  FIG. 2D , the user had clicked the mouse to select window  56  as a permanent window, and then moved the mouse out of window  56 , such as along path  59 , then the screen would be left in the configuration of  FIG. 2D . Alternatively, the user could opt to maintain window  52  as a permanent window by clicking within the window when the cursor is positioned as shown in  FIG. 2F . 
       FIG. 3A  illustrates the beginning of an alternative sequence, using the spring-loaded enclosure system of the present invention.  FIG. 3A  correspond closely to  FIG. 2C . However, in this instance, the user executes a drag operation along the path  60  which crosses the boundary of the temporary window  56  back into temporary window  52 . When the boundary of temporary window  56  is crossed, the temporary window  56  is removed from the screen, as illustrated in  FIG. 3B , and the altered view  53  of the identifier and the cursor reside within temporary window  52 . If the user had moved the cursor along path  75 , rather than path  60 , temporary window  56  would close, but temporary window  52  would remain open. The user could close temporary window  52  by moving the cursor back into temporary window  52  and then back out as illustrated by path  76 . 
     As shown in  FIG. 3B , the user continues to browse by dragging along the path  61  to identifier  62 . By pausing over the identifier  62 , temporary window  63 , as illustrated in  FIG. 3C , is opened, centered over the identifier  62 . Also, the altered view  53  of the identifier and the cursor reside within temporary window  63 . 
       FIG. 3C  also illustrates what happens when the temporary window  63  corresponds to a window, e.g., window  25 , which already existed on the desktop before the drag operation began. In this instance, the window  25  is removed from the screen. Also, a zoom operation indicated by the arrows  64  and  65  is graphically depicted on the screen to indicate to the user the movement of the window  25  to the temporary window  63 . This zoom operation can take a variety of graphical characteristics difficult to show in the storyboards of  FIGS. 3A-3E . However, it will be understood by those skilled in the art how this operation is accomplished. 
     In  FIG. 3C , the drag operation continues along path  66  to point  67 , and the mouse button is released indicating the end of the drag operation.  FIG. 3D  illustrates one alternative outcome. In this case, the identifier is moved into the temporary window  63  and the temporary window is moved back to the original position of window  25 . Window  25 , including the identifier  30 , remains on the screen. The identifier  30  has been removed from window  24  because windows  25  and  24  reside on the same disk. Alternatively, the user may have the option of keeping the temporary window  63  as the permanent window. This is illustrated in  FIG. 3E . After the drag operation, the identifier  30  is left within the temporary window  63 . The cursor  50  returns to its normal shape. The user has the option of closing the temporary window, which leaves the position of the real window unaffected. When the enclosure is opened again, the window will be located in its old location. If the user chooses not to close the temporary window but rather moves or resizes the temporary window before closing it, when the window is subsequently re-opened it will be located at the new position and size. 
     In the illustrations of  FIGS. 2A-2D  and  3 A- 3 E, temporary windows are indicated by hatching a bar across the top of the window. In a preferred system, these windows may be rendered translucent, or other effects may be used as suits the needs of a particular implementation. As mentioned above, some means of indicating a temporary window, as opposed to a regular window, may be provided within the desktop. 
     II. Interface Management Logic Implementation ( FIGS. 4-13 ) 
     As mentioned with reference to  FIG. 1 , a computer system implementing the spring-loaded enclosure mechanism according to the present invention includes control software.  FIGS. 4 and 5  provide a conceptual software architecture for managing spring-loaded enclosures according to the present invention. 
     As shown in  FIG. 4 , the system includes cursor position logic  100  which maintains information concerning the current position of the cursor within the desktop area on the display. Also, drag logic  101  monitors the mouse actions including the mouse button and movement of the mouse to indicate the execution of a drag operation. Obviously with pointing devices other than a mouse, a drag operation may be indicated by a variety of user actions. 
     The system also includes timer logic  102  for detecting a pause of the cursor over a particular identifier in the spring-loaded enclosure management routine. Also, the timer  102  may be used for other purposes. 
     Also included in the control software is spring-loaded enclosure management logic  103 . This management logic maintains a list of temporary windows referred to as the “Sprung Stack”, and an indicator of the Top temporary window in the Sprung Stack. The Sprung Stack consists of a set of pointers to records that identify the state of the temporary windows. These records are referred to as Sprung Records. 
     The system further includes window management logic  104  which performs a variety of functions known to those of skill in the art for managing windows. This window management logic includes a system for opening and closing windows on the desktop in response to pointer actions, and maintains a desktop Window List. The desktop Window List comprises a list of windows that are opened on the desktop, their positions on the desktop, and other characteristics of the window, including the location, the types of windows, and information about icons, if any, enclosed by the window. Further, enclosure windows in the list point to a window record that contains information about the enclosures that are represented by identifiers in the windows, and such other information as is needed. 
     In cooperation with the drag logic  101 , the window management logic  104  maintains a parameter referred to as the Current Window, which indicates the window within which the cursor currently resides. Also, the window management logic  104  maintains a parameter referred to as the Last Window which indicates the last window which the cursor was over, for instance if the cursor moves from inside a window to outside a window. Finally, the window management logic maintains a record referred to as the Current Enclosure which indicates the identifier that the cursor is presently positioned over. 
     A final component of the control software is known as the drawer management logic  105 . The drawer management logic manages windows which are maintained on the screen with a desk drawer metaphor. In particular, the windows are positioned along the periphery of the desktop. They can be slid off the desktop leaving only a drawer identifier on the perimeter of the desktop display. When the desk drawer window is opened in response to a cursor action executed by the user, the window slides onto the screen obscuring any windows underneath it. When the user is done with the window, it can be slid back offscreen to reveal the underlying windows. The desk drawer management logic  105  maintains a Threshold parameter which indicates the distance from the perimeter of the desktop within which a cursor movement will result in opening of the drawer, and a Current Drawer parameter indicating the drawer within which the cursor is currently positioned. 
     The drawer management logic is described in detail in our co-pending U.S. patent application entitled COMPUTER SYSTEM WITH GRAPHICAL USER INTERFACE INCLUDING DRAWER-LIKE WINDOWS, invented by Thomas J. Conrad and Elizabeth Moller. 
       FIG. 5  illustrates the basic data records maintained by the spring-loaded enclosure management logic  103  and the window management logic  104 . In particular, the window management logic  104  maintains a desktop window list  110 . It includes an entry for the desktop with a set of pointers to a list of identifiers within the desktop. Also, each enclosure which is opened as a window within the desktop is added to the list as indicated. Thus, the list includes window  1 , window  2 , window  3 , etc. Associated with each window, e.g., window  1 , is an icon pointer which points to a record of identifiers, e.g., record  111 . Each identifier within window  1  is maintained in a list  111 . Thus, identifier  1  includes a pointer to an enclosure record  112 , which indicates the type of enclosure, whether the enclosure has been opened on the desktop, the location on the desktop of the identifier, the location in memory of the object represented by the identifier, etc. If the identifier has been opened on the desktop, then information about its location will be included in the window list  110 . 
     The spring-loaded enclosure management logic  103  maintains a Sprung Stack  113 . This includes a list of temporary windows, window X, window Y, and so on, which have been opened during a drag operation according to the present invention. Each entry in the Sprung Stack points to a Sprung Record  114 . The Sprung Record maintains such information about the temporary window as whether the window was previously opened on the desktop and, if so, where; the location on the desktop of the temporary window; a pointer to a list of identifiers (e.g.,  111 ) for the temporary window; etc. 
     A functional flow chart for executing the spring-loaded enclosure management is provided with reference to  FIGS. 6-13 , in which  FIG. 6  is the Main Loop. The Main Loop shown in  FIG. 6  begins at block  600  where it monitors the mouse button. If the mouse button is not down, the algorithm loops at block  600 . If the mouse button is down, then the algorithm passes through the Drawer Stuff routine which handles clicks of the mouse button in drawers represented by block  601  which is shown in detail in  FIG. 12 . After the Drawer Stuff routine  601 , the algorithm tests to determine whether the cursor is over an object (block  602 ). If it is not over an object, then the algorithm handles other clicks and cursor operations (block  603 ) and loops to block  600 . If the cursor is over an object at block  602 , then the algorithm monitors the mouse button (block  604 ). If the mouse button does not remain down, then a Select Object routine is executed, as indicated at block  605 , and the algorithm loops to block  600 . The select object routine  605  may result in a variety of operations as known in the art, such as opening an application window. 
     If the mouse button remains down at block  604 , then a drag operation is indicated. In this case, the routine creates a grey outline (referred to as an “altered view” above) of the object and attaches the grey outline to the cursor. Also, the Last Window parameter is set equal to the Current Window parameter (block  606 ). 
     After block  606 , the mouse button is monitored (block  607 ). If the mouse button is released, then the algorithm branches to the Finish Drag routine represented by block  608  which is shown in detail in  FIG. 13 . If the mouse button remains down, then the algorithm proceeds through the Drag Over Window routine represented by block  609  shown in  FIG. 7 . After the Drag Over Window routine at block  609 , the algorithm loops to block  607  to monitor the drag operation. 
       FIG. 7  illustrates the Drag Over Window routine represented by block  609  in  FIG. 6 . The Drag Over Window routine is started from block  607 . First, it tests whether the Current Window parameter is equal to the Last Window parameter (block  700 ). If it is not equal, the border of the last window has been crossed and the algorithm branches to the Window End Drag routine represented by block  701  which is shown in detail in  FIG. 10 . If the Current Window remains equal to the Last Window (the cursor remains within the boundary of the window), then the algorithm branches to the In Window routine represented by block  702 , as shown in detail in  FIG. 8 . From the Window End Drag routine of block  701 , and the In Window routine of block  702 , the algorithm proceeds through block  703  where Last Window is again set to Current Window. Next, the algorithm tests whether the Current Window is a drawer (block  704 ). If it is not a drawer, then the routine returns to block  607  of  FIG. 6 . If the Current Window is a drawer, then the algorithm tests whether the Current Drawer is equal to the Current Window (block  705 ). If not, then the cursor has moved out of the Current Drawer, and the Current Drawer is closed (block  706 ). The Current Drawer parameter is set to the Current Window in block  707  and the algorithm loops back to block  607  of  FIG. 6 . If, in block  705 , the Current Window is not a drawer, the algorithm returns to block  607  of  FIG. 6 . 
       FIG. 8  illustrates the In Window routine represented by block  702  of  FIG. 7 . The In Window routine is entered from block  700  of  FIG. 7 . First, the algorithm tests whether the Current Window is equal to Current Drawer (block  800 ). If it is the Current Drawer, then the In Drawer routine represented by block  801  and shown in detail in  FIG. 11  is executed. If the Current Window is not equal to the Current Drawer in block  800 , and from the output of the In Drawer routine in block  801 , the algorithm branches to block  802 , where the algorithm determines whether the cursor is over an enclosure icon. If it is not over an enclosure icon, then the algorithm returns to block  703  of  FIG. 7 . Otherwise, the algorithm branches to block  803 , where a timer is set to zero, and the Last Enclosure parameter is set equal to the Current Enclosure. Next, the algorithm monitors whether the cursor remains over the Current Enclosure by testing whether the Last Enclosure remains equal to the Current Enclosure in block  804 . If it does not remain over the Current Enclosure, then the timer is tested (block  805 ). If the timer is equal to zero, then the algorithm branches to block  703  of  FIG. 7 . If it is not equal to zero, the timer is first reset to zero in block  806  and then returns to block  703  of  FIG. 7 . 
     If, in block  804 , the cursor remains over the Current Enclosure, the algorithm tests whether the timer is equal to zero in bock  807 . If the timer is not equal to zero, the algorithm tests whether the timer has expired in block  808 . If it has expired, then the Spring Open Window routine represented by block  809  and shown in detail in  FIG. 9  is executed. After the Spring Open Window routine in block  809 , the algorithm returns to block  703  of  FIG. 7 . 
     If in block  807  the timer was equal to zero, then the timer is started (block  810 ) and the algorithm loops to block  804  to begin monitoring whether the cursor remains over the enclosure until expiration of the timer. 
       FIG. 9  illustrates the Spring Open Window routine corresponding to block  809  of  FIG. 8 . The algorithm is entered from block  808  of  FIG. 8 . The first step is to create the Sprung Record for the particular window being sprung open (block  900 ). Next, the algorithm determines whether the window being sprung open is already open on the desktop (block  901 ). If it is already open, then the existing window size and position are saved in the Sprung Record (block  902 ). Next, the existing window is removed from the screen (block  903 ). Coupled with removing the existing window, a zoom operation may be executed to graphically illustrate movement of the window being closed to the new position. 
     If the window to be sprung open was not already open at block  901 , or after block  903 , the algorithm opens a temporary window centered about the cursor position (block  904 ). Next, the temporary window centered about the cursor position is tested to determine whether it is partially offscreen (block  905 ). If it is partially offscreen, then the window is moved onto the screen (block  906 ). After block  906 , or if the window is completely on the screen at block  905 , then the algorithm tests whether the window is too big for the sprung open routine (block  907 ). If the window is too big then it is resized to fit on the monitor that the cursor is currently on, leaving several pixels of free space around the window (block  908 ). 
     After block  907 , if the window is not too big, or after it is resized in block  908 , the algorithm loops to block  909  where the window reference (description of the temporary window) is stored in the Sprung Record. Next, the Sprung Record is pushed onto the Sprung Stack (block  910 ). After block  910 , the algorithm returns to block  703  of  FIG. 7 . 
       FIG. 10  illustrates the Window End Drag routine represented by block  1001  of  FIG. 7 . The Window End Drag routine is entered from block  700  of  FIG. 7 . The first step is to determine whether the Last Window is a slid open drawer in block  1001 . If it is a slid open drawer, then the drawer is closed (block  1002 ). 
     If the Last Window is not an open drawer, or after the drawer is shut in block  1002 , then the algorithm tests whether the Last Window is the Top Window in the Sprung Stack (block  1003 ). If it is not, then the algorithm returns to block  1003  of  FIG. 7  or to block  1300  of  FIG. 13 . 
     If at block  1003  the Last Window is the Top window in the sprung stack or if the algorithm is entered from block  1301  of  FIG. 13 , then the Last Window is popped off the Top of the Sprung Stack (block  1004 ). 
     After the Sprung Record is popped off of the Top of the Sprung Stack, the temporary window corresponding to the Top record is closed (block  1005 ). Next, the algorithm determines whether the Top window (being popped off the stack) needs to be re-opened (block  1006 ). This occurs if the Top was open at another location on the desktop before the temporary window was opened during the drag operation. If so, the Top is re-opened at the location indicated in the Sprung Record, and then the algorithm determines whether it should be resized (block  1007 ). If it needs to be resized, then the resize operation is executed (block  1008 ). If the Top that is being popped off the top of the Sprung Stack does not need to be resized, or after the resizing in block  1008 , then the new Top of the Sprung Stack is opened (block  1009 ). After block  1009 , or if the window does not need to be re-opened from block  1006 , the algorithm returns to block  1003  of  FIG. 7  or to block  1300  of  FIG. 13 . 
       FIG. 11  illustrates the In Drawer routine corresponding to block  801  of  FIG. 8 . The In Drawer routine in entered from block  800  of  FIG. 8  and first tests whether the cursor is within the Threshold of the drawer management logic (block  1100 ). If it is not, then the algorithm returns to block  802  of  FIG. 8 . If it is within the Threshold, then the drawer is slid open one notch (block  1101 ). After block  1101 , the algorithm returns to block  802  of  FIG. 8 . By keeping the cursor in this position, the user causes the drawer to gradually slide open. 
       FIG. 12  illustrates the Drawer Stuff routine entered from block  600  of  FIG. 6 . It first tests whether the button remains down (block  1200 ). If it is down, then the algorithm returns to block  602  of  FIG. 6 . If the button has been released, then the algorithm tests whether the Current Drawer is equal to the Current Window (block  1201 ). If the cursor remains within the Current Window, the algorithm determines whether the click (release detected in block  1200 ) occurred in the title bar of the opened drawer (block  1202 ). If not, the algorithm returns to block  602  of  FIG. 6 . If the click was in the title bar, or if the click was not in the Current Drawer as indicated at block  1201 , then the Current Drawer is removed from the screen (block  1203 ). Next, the algorithm determines whether the Current Window is a drawer at all (block  1204 ). If not, it returns to block  602 . If the Current Window is a drawer, then the drawer is opened (block  1205 ). This occurs when a drawer is open and another drawer is clicked. 
       FIG. 13  illustrates the Finish Drag routine corresponding to block  608  of  FIG. 6 . The Finish Drag routine is entered from block  607  of  FIG. 6 . The algorithm first determines whether the Sprung Stack is empty in block  1300 . If it is not empty, then the Window End Drag routine is executed as indicated at block  1301 . The Window End Drag routine of block  1301  enters the routine of  FIG. 10  at block  1004 . After the Window End Drag routine of block  1301 , the algorithm returns to block  1300 . If the Sprung Stack was empty at block  1300 , then the algorithm returns to block  600  of  FIG. 6 . 
     III. Alternate Spring Open Gestures ( FIGS. 14A-B  and  15 A-B) 
       FIGS. 14A-B  and  15 A-B illustrate alternative mouse gestures that may be used for springing open enclosures according to the present invention. The preferred system, as illustrated above, springs open enclosures in response to a pause of the cursor over the enclosure to be opened, as described with reference to  FIG. 8 . Alternative systems may be implemented that spring open enclosures based on other pointer gestures. Two examples are shown in  FIGS. 14A-B  and  FIGS. 15A-B . 
     In  FIGS. 14A-B , enclosure icon  1400  and a dragged icon  1401  are shown. The enclosure icon  1400  has a hot region, or temporary window open region,  1402  and a main box  1404 . If the cursor is moved into the hot region  1402 , as illustrated in  FIG. 14B , then the sprung open enclosure will be open. If the cursor does not hit the hot region  1402 , then no action occurs. If the mouse button is released over the main box  1404 , then the dragged object goes inside the enclosure. 
     In  FIGS. 15A and 15B , another alternative sequence is shown. In this sequence, a dragged icon  1501  is dragged over a folder. When this occurs, a select icon appears, such as an opened folder icon  1502  with a split pie symbol. The split pie has a first side  1503  and a second side  1504 . If the user moves the cursor downward to the second side  1504 , as illustrated in  FIG. 15B , then the sprung open enclosure is opened. Alternatively, if the user moves the cursor upward into the first side  1503 , then some other action may occur. If user moves the cursor through the split pie, then the select icon is removed and the original icon reappears. As before, if the mouse button is released over the opened folder, then the dragged object goes inside the folder. 
     Those skilled in the art will appreciate that there are a variety of techniques for indicating the desire to spring open an enclosure during a drag operation. 
     IV. Conclusion 
     A new behavior of the graphical user interface has been provided which allows a user to open and close enclosures, such as folders in the Macintosh Finder™ environment, while dragging some other object. When the user pauses, gestures, or rolls over a hot spot on the object during the drag, a temporary window corresponding to that object is opened on top of the cursor. This allows the user to browse inside the enclosure and possibly open a hierarchy of enclosures contained within the newly opened window during the drag operation. The user thus has access to the entire storage system hierarchy during a drag operation. By using the spring loaded enclosure mechanism, the user is left free to browse while dragging, rather than being forced to set up source and destination windows before a drag begins. This greatly improves the basic copy and move functions provided by the graphical user interfaces based on windows and icons. 
     The foregoing description of preferred embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.