SYSTEM TO ASSOCIATE CONTROL WITH APPLICATIONS USING DRAG AND DROP INTERFACE

Abstract: A system for updating or improving an application by dragging a control to the application and dropping the control in it. The control verifies that the new application interface is the same as the control interface. Known application interfaces may be added to controls to support the use of multiple interfaces.

Description: SYSTEM TO ASSOCIATE CONTROL WITH APPLICATIONS USING DRAG AND DROP INTERFACE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the field of computer software interface methods and more particularly, to a method of improving an application. 2. The Prior Art Many computer applications operate by using similar functions. For example, most applications perform operations on files and therefore provide the user with functions to Open a file, Create a New file, Save a file and Save a file under a different name. Before object-oriented technology became widely used, improvements to applications took a long time to im- plement. A user of an application could not add improvements to the application unless the source code of the application was available to the user. But, even with the source code, the improvements to an application required a change or changes to the source code, followed by a cycle of debugging and re-building until the improved application worked properly. Users without the source code had to wait months or years for improvements in the form of new versions of the application. Moreover, improvements made by the publisher are out of the control of the user. Applications may end up having improvements in which the user may have no interest or lack all of the improvements the user wanted. The advent of object oriented coding made it possible for users to write objects that deal with a specific problem (for example, in the case of the File Open function, determining the file name for the file the user wishes to Open). For the most part, however, even object-oriented systems do not allow users to add a control onto an existing program. Moreover, even ob- ject-oriented systems have compile and re-build stages and most users still wait for improvements months later. Some publishers have provided applications that can modify other applications during installation. A new application with new functions can be used to update an existing application that can be improved by incor- poration of the new functions. The update is accomplished with programs that can modify the code of the existing application. The programs are in- serted into the existing application during the installation. For example, some programs have code in the installation package that will prompt a user for whether or not to add a menu option (and hot key) onto Microsoft Word. The problem is that the update requires an installation, and it requires for the new program to have extensive knowledge of how the first program works (how it's menus and hot keys are set up, as well as knowledge of how it inserts things). It would be desirable for a user to be able to add an improvement to an application after the program's distribution and without having to re-compile the code. It would be desirable for a user to be able to add an improvement to an application by duplicating such an improvement from a different program. SUMMARY OF THE INVENTION In view of the above, the present invention is directed to a system for adding features to applications in a computer system comprising a processing unit, a selecting device responsive to a user, and a display screen. The system includes an application executing in the processing unit. The application is represented by a display window and has an application interface. A control representation having a control interface is included in the system. The control representation is operative to execute a control function when the control representation is selected by a user with the se- lecting device. The control representation is movable to the application by user action, and is further operative to execute the control function during execution of the application when the application interface is compatible with the control interface. In this manner, a control function not previously available to the application is made part of the application. The present invention is further directed to a method of updating a control to an application having the steps of providing a display window and an application interface for the application on display screen and providing a control representation for performing a function not available to the application. The control representation has a control interface and a control im- age in a part of the display screen separate from the display window of the application. The user picks the control representation by holding a pointer over the control image, moving the control image to an area in the application display window and releasing the control representation in the area in the application display window. The function associated with the control representation is then enabled. It is accordingly an object of the present invention to provide a system that allows a user to add improvements to an application without having to change and re-compile code. It is further an object of the present invention to provide a system that allows a user to add a function in one application to another applica- tion by moving an object representative of the function from one application to the other application. DESCRIPTION OF THE DRAWINGS The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof: FIG. 1 is a block diagram of a computer system in which the present invention finds particular use. FIG. 2 is a display screen having display windows for two applications. FIG. 3 is a magnified view of.the display screen in FIG. 2, after moving a control icon from one program to another according to the inven- tion. FIG. 4 is a flow chart of a preferred method according to the present invention. FIG. 5 is pseudo-code for implementing the flow chart in FIG. 4. FIG. 6 is pseudo-code for implementing an alternative method of verifying a shared interface in the flow chart of FIG. 4. FIG. 7A and 7B are Java listings of different classes in different applications that accomplish the same tasks. DESCRIPTION OF THE PREFERRED EMBODIMENT The description that follows refers to the drawings where like elements are identified by like numerals throughout. Although a presently preferred system is described, it can be appreciated by one of ordinary skill in the art that different embodiments are possible without departing from the scope of the invention. Improvements in object-oriented technology have resulted in the proliferation of graphical user interfaces in computer systems. Graphical user interfaces have made computers easier to use by disposing of the need to learn complex instruction and command sets. In the place of instruction and command sets are pictures or objects and selecting and pointing devices. The ease of looking at pictures and selecting objects that convey that a func- tion is to be performed by selecting the object reduces the time to master applications. While graphical user interfaces have been spawned by improvements in object-oriented technology, function-oriented software has not completely disappeared. Much of the software being developed includes elements of both object-oriented and function-oriented software. Although the description that follows focuses on an object-oriented system, one of ordinary skill in the art will appreciate that the use of function-oriented elements to carry out the objectives of the present invention is within the scope of the invention. FIG. 1 is a block diagram of a computer system 10 in a preferred embodiment of the present invention. The computer system 10 in FIG. 1 includes an operating system 20, an application level 30, a user interface 40, a drag controller 44, a Java interpreter 50, and an I/O manager 60. The computer system 10 may be any computer system using any processor. In a preferred embodiment, the computer system 10 operates using a processor (not shown) with sufficient power and speed to handle the drawing and redrawing of hundreds of images per minute. The memory (not shown) must be sufficient to handle the large amounts of memory which image data traditionally occupies. The operating system 20 manages basic services, such as memory, clock, initialization and power management. The operating system in a preferred embodiment includes access to a graphical user interface. The operating system preferably includes multi-tasking features such as real-time preemptive multi-processing. One example of such an operating system is the OS-9000 operating system. The application level 30 includes all computer applications that have been installed to run on the computer. These applications include a notepad 31, a calculator 32, a clock 33, a web browser 34, a phone 35 and a word processing program 36. All applications are preferably written in the same object-oriented programming language to ensure portability. Applications are programmed as objects in an object-oriented environment. The ob- jects for applications preferably include an interface which defines the methods or functions performed by the application. In a preferred embodiment, all applications are written in the Java programming language. More information on the Java programming language may be obtained by referring to Arnold and Gostling, The Java Programming Language, Addison-Wesley, 1996. The I/O manager 60 provides an interface between the rest of the system and the input/output devices. In the computer system 10 in FIG. 1 , the I/O manager 60 interfaces with a keyboard 62, a serial line 64, a touch screen 66, a display screen 68, and a selecting device 70. The selecting device 70 is understood to include any device able to control a pointer on the screen and to select and invoke screen objects, such as a mouse, a roller ball with buttons, a touch pad, and any other suitable device. The user interface 40 causes icons or graphic images of objects to be displayed on the display screen and invokes functions associated with the object when the user selects the objects on the screen with the pointer. The graphic images used for objects may include buttons, scroll bars, dropdown menus, radio buttons and other well known objects. In a preferred embodiment, the user interface 40 invokes functions associated with classes defined in Java. Objects may be displayed and included as control representa- tions 46 in an application to provide a way for a user to easily invoke the functions performed by the application. The user interface 40 enables the user to select the control representations 46 to perform the function associated with it. Each control representation 46 includes a control interface which defines the methods or functions performed by the application. In a preferred embodiment, each control representation 46 implements a process of verifying the extent to which the functionality or, the interface of any application into which it is dropped matches its own control interface. As described further with reference to FIG. 4, the control representation 46 verifies functionality by ensuring that the application into which it is dropped performs all of the methods performed by the control representation 46. In a preferred embodiment, the user interface 40 includes a drag controller 44 for carrying out the movement of an object from one loca- tion of the screen to another. The drag controller 44 operates as a central location for handling information used in the movement of an object. Preferably, the drag controller 44 stores information about the object selected by the user for movement. The drag controller 44 also determines whether a target object such as an application into which a control representation 46 is to be moved can accept a control representation 46. The Java Interpreter 50 converts classes and applications into a native code that is to be executed by the processor. In alternative embodiment, programming languages that may or may not use an interpreter may be used. FIGs. 2 and 3 illustrate an example of how the computer system 10 in FIG. 1 allows a user to drag and drop controls between applications. FIG. 2 depicts two display windows 100 and 150 for two applications. The first display window 100 is for a game application and the second display window 150 belongs to a debugger application. The first display window 100 includes a control panel 120 which is an object that contains control representations labeled NEW 110, HINT 112 and SKIP 114. It appears as though the game application of display window 100 was shipped without a QUIT function. Rather than changing source code and then re-compiling the code, the user can by the present invention add the QUIT function by picking it from an application having a QUIT function, if the control interface for the QUIT function is the same as that of the game application. The user adds the function by selecting the control representation for QUIT 130 in the second display window 150 using a pointer 102, moving the control representation along a path such as that at 140, and dropping it in the control panel 120 of the first display window 100. FIG. 3 shows the new control representation 160 in the control panel 120. The QUIT function then is enabled such that the game application stops functioning when the control representation is pressed. The QUIT function is enabled because the QUIT control representation and the application have the same interface, which means that each can execute certain transactions. For example, if the user desired to transfer a spell-checking function from one application to another, the spell- checking control would have to be able to ask for a document and how to re- turn the new (changed) document. The application receiving the spell- checking control does not need to know how the spell checker works. The application has an interface that views the control as an object with which it can exchange documents. At a later time, another control representation may be written using the same interface for a new application. For example, a new applica- tion may include a translate to French control for translating an English document to French. It could be dragged and dropped into an existing application in the manner illustrated in FIGs. 2 and 3 and perform properly. One advantage of the process illustrated in FIGs. 2 and 3 is that the French translation function may be added without having to undergo an installation procedure of another program and without modifying and re-compiling the source code to the application. It may be possible that the existing application may not share an interface with the control interface of the control representation (e.g. the translate to French control). In such a case, the program would not know how to perform certain functions such as how to exchange documents. In that case, the control could still be dragged and dropped in the program; however, the control representation would sense the lack of compatibility and disable itself since it could not communicate with the existing application. FIG. 4 illustrates a flow chart of the process described in FIGs. 2 and 3. At step s1, the user starts dragging a control from the first application to the second application. As soon as the dragging starts, the object registers itself with the Drag Controller 44 (shown in FIG. 1 ). As the control moves, the Drag Controller 44 communicates with other objects on the screen to determine if the current location is a valid drop location or not. The user releases the control representation on a new control panel 120 (shown in FIG. 2) that can accept it. At step s2, the Drag Controller 44 sends the control to the control panel 120. At step s3, the second application creates an instance of the control. In creating the instance, the second application copies the control object and begins to interface with it. At step s4, the panel 120 receives configuration information from the control, so that it may be saved in the application's configuration. At step s5, the panel places the control in itself and adjusts its own re-layout, if necessary, to make sure that all controls are visible and displayed properly. At step s6, the control then interrogates the application to determine if it has all the necessary methods for the control. At decision block d6, if the interfaces are shared, then at step s7, the control is enabled. At decision block d6, If the interfaces are not shared, then the control disables itself at step s8. In step s6 in FIG. 4, the control goes through each interface, or method (or process, function, message, etc.) that it will need and attempts to find the same method defined in the application. The control does not need to obtain the implementation of each method, only its definition. The flow chart in FIG. 4 may be implemented using code similar to the pseudo-code shown in FIG. 5. FIG. 5 denotes the steps performed and the objects performing the steps. Alternative implementations to step s6 may be used to determine if an application and a control share sufficient functionality. For exam- pie, the process in step s6 may be simplified by taking advantage of standard interfaces, such as the CUT/COPY/PASTE interface. If the control representation 46 determines that a function (e.g. the CUT function) of the standard interface is shared, the functionality of the standard interface is assumed to be shared. The Java keyword implements may be used to deter- mine if functionality is shared. An example of the use of implements is illustrated by the pseudo-code in FIG. 6. The pseudo-code in FIG. 6 may be used at step s6 in the flow chart in FIG. 4. Controls may get information needed to determine if it shares sufficient functionality with the application from the applications Class. Much as an interface defines what methods exist in a class, the class also defines what methods exist. The class however, defines the description of the methods as well. For example, FIG. 7A is a Java listing for a class called "Curren- cyUpdatelnterface." If a control requires those methods in an application, it could test for this by executing: Line 1 : if (application implements CurrencyUpdatelnterface) ... Assume that a commercial package by company XYZ exists as defined in FIG. 7B. A comparison between FIGs. 7A and 7B shows that the two CurrencyUpdaters do the same thing. But, because the interface is different, the control will not enable itself in the application. XYZ's product can be made to work in the program in FIG. 7A by using the following: Line 2: if ( (application implements CurrencyUpdater) *or* (application instanceof XYZCurrencyUpdater) ) ... By adding line 2 to program XYZ, as the program of this invention accomplishes, both interfaces will be supported. It is to be appreciated by one of skill in the art that alternative embodiments are possible without departing from the scope of the present invention. Further, a wide range of changes and modifications can be made to the preferred embodiments described above. It is therefore intended that the foregoing description illustrates rather than limits this invention, and that it is the following claims, including all equivalents, which define this invention.

Claims: WE CLAIM: 1. A system for adding features to applications comprising: a computer system comprising a processing unit, a se- lecting device responsive to a user, and a display screen; an application executing in the processing unit and rep- resented by a display window on the display screen, the application having an application interface; and a control representation having a control interface, the control representation being operative to execute a control function when said control representation is selected by a user with the select- ing device, said control representation being movable to said applica- tion by the user and operative to execute the control function during execution of the application when the application interface is compati- ble with the control interface thereby enabling a control function not previously available to the application. 2. The system of Claim 1 further comprising: a second application represented by a second display window, the control representation being a part of the second applica- tion such that the control representation is moved from the second ap- plication to the first application. 3. The system of Claim 1 further comprising: a second application represented by a second display window, the control representation being located in the second display window; and the control representation comprises an interface control program for maintaining a group of interface definitions and for check- ing for the first application interface among the group before enabling the control representation in the first application. 4. The system of Claim 3 wherein the control representation enables the operation of the function by verifying that the application interface of the first application is known to the control representation. 5. A method of adding a control to an application, the application having a display window on a display screen and a control representation for performing a function not available in the application, the control rep- resentation being in a part of the display screen separate from the dis- play window of the application, the method comprising the steps of: moving the control representation by a user action to a selected area in the display window; and enabling the function associated with the control repre- sentation. 6. The method of Claim 5 wherein the control representation comprises a control interface and the application comprises an application interface further comprising the steps of: verifying that the control interface of the control repre- sentation is similar to the application interface of the application; and enabling the control representation when the control in- terface of the control representation is similar to the application inter- face of the application. 7. The method of Claim 6 further comprising the steps of: maintaining a group of alternative interfaces in the con- trol representations; searching for the application interface in the group of al- ternative interfaces supported by the control representation when the control interface of the control representation is different from the ap- plication interface; and designating an alternative control interface in the control representation for operating the control representation in the first ap- plication. 8. The method of Claim 7 further comprising the steps of: defining a new interface; and adding the new interface to the group of alternative in- terfaces supported by the first application.

Inventors: BANKLER BRIAN, MOON BILLY G, BANKLER, BRIAN, MOON, BILLY, G.
Applicants: ERICSSON GE MOBILE INC, ERICSSON, INC.
Application year: 1998
Main classification: G06F9
IPC codes: G06F3, G06F9