WebSpeechInputListener.h   [plain text]


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#ifndef WebSpeechInputListener_h
#define WebSpeechInputListener_h

#include "WebSpeechInputResult.h"

namespace WebKit {

class WebString;

// Provides a WebKit API called by the embedder.
// A typical sequence of calls to the listener would be
//   1 call to didCompleteRecording
//   0 or more calls to setRecognitionResult
//   1 call to didCompleteRecognition
class WebSpeechInputListener {
public:
    // Informs that audio recording has completed and recognition is underway. This gets invoked
    // irrespective of whether recording was stopped automatically by the 'endpointer' or if
    // WebSpeechInputController::stopRecording() was called.
    // Typically after this call the listener would update the UI to reflect that recognition is
    // in progress.
    virtual void didCompleteRecording(int) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Gives results from speech recognition, either partial or the final results.
    // This method can potentially get called multiple times if there are partial results
    // available as the user keeps speaking. If the speech could not be recognized properly
    // or if there was any other errors in the process, this method may never be called.
    virtual void setRecognitionResult(int, const WebSpeechInputResultArray&) { WEBKIT_ASSERT_NOT_REACHED(); }

    // Informs that speech recognition has completed. This gets invoked irrespective of whether
    // recognition was succesful or not, whether setRecognitionResult() was invoked or not. The
    // handler typically frees up any temporary resources allocated and waits for the next speech
    // recognition request.
    virtual void didCompleteRecognition(int) { WEBKIT_ASSERT_NOT_REACHED(); }

protected:
    ~WebSpeechInputListener() { }
};

} // namespace WebKit

#endif // WebSpeechInputListener_h