Application: gvSIG desktop

/* $Id$ */

/* //////////////////////////////////////////////////////////////////////////

//                                                                         //

// This code is Copyright (c) 2004 LizardTech, Inc, 1008 Western Avenue,   //

// Suite 200, Seattle, WA 98104.  Unauthorized use or distribution         //

// prohibited.  Access to and use of this code is permitted only under     //

// license from LizardTech, Inc.  Portions of the code are protected by    //

// US and foreign patents and other filings. All Rights Reserved.          //

//                                                                         //

////////////////////////////////////////////////////////////////////////// */

/* PUBLIC */

#ifndef LTI_DELEGATES_H

#define LTI_DELEGATES_H

// lt_lib_base

#include "lt_base.h"

LT_BEGIN_NAMESPACE(LizardTech)

#if defined(LT_COMPILER_MS)

   #pragma warning(push,4)

#endif

/**

 * interrupt delegate (callback) base class

 *

 * This abstract class is used for implementing a mechanism to determine if

 * a potentially long-running operation is to be interrupted, such as

 * LTIImageStage::read() or LTIImageWriter::write().  During these sorts of

 * operations, an object which has an interrupt delegate may periodically

 * call the delegate's getInterruptStatus() method to determine if the

 * operation should be aborted.  If this function returns a value other than

 * LT_STS_Success, then the object will abort the operation  and return that

 * status value.

 *

 * Interrupt delegates are typically used in environments such as GUI encoders.

 *

 * A "delegate" is simply an object-oriented version of a callback function.

 */

class LTIInterruptDelegate

{

public:

   /**

    * check for interrupt

    *

    * This function should be implemented to indicate whether some user-defined

    * event indicates that the operation should be terminated.  If an interrupt

    * is requested, a value other than LT_STS_Success should be returned.

    *

    * @return LT_STS_Success if no interrupt requested; any other (nonzero)

    *         value if an interrupt is requested

    */

   virtual LT_STATUS getInterruptStatus() const = 0;

};

/**

 * progress delegate (callback) base class

 *

 * This abstract class is used for implementing a mechanism to report the

 * progress (percent complete) of a potentially long-running operation.

 * During these sorts of operations, an object which has a progress delegate

 * may periodically call the delegate's setProgressStatus() method to report

 * the percent of the operation completed.

 *

 * Progress delegates are typically used in GUI environments as a means of

 * displaying percent-complete or time-remaining.

 *

 * A "delegate" is simply an object-oriented version of a callback function.

 */

class LTIProgressDelegate

{

public:

   /**

    * set percent completed

    *

    * This function should be implemented to report to the client application

    * the progress of a long-running operation.

    *

    * @param percentComplete the percent complete; this must be a value in the

    *                        range 0.0 to 1.0 inclusive

    * @return LT_STS_Success if function succeeded, nonzero if some error occurred

    */

   virtual LT_STATUS setProgressStatus(float percentComplete) = 0;

};

LT_END_NAMESPACE(LizardTech)

#if defined(LT_COMPILER_MS)

        #pragma warning(pop)

#endif

#endif // LTI_DELEGATES_H