PlatformGestureRecognizer.h   [plain text]

/*
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#ifndef PlatformGestureRecognizer_h
#define PlatformGestureRecognizer_h

#include <wtf/PassOwnPtr.h>

namespace WebCore {

class EventHandler;
class PlatformGestureRecognizer;
class PlatformTouchEvent;

// A GestureRecognizer detects gestures occurring in the touch event.
// In response to a given touch event, the GestureRecognizer, updates
// its internal state and optionally dispatches synthetic events to the
// invoking EventHandler instance.
class PlatformGestureRecognizer {
protected:
    PlatformGestureRecognizer();

public:
    static PassOwnPtr<PlatformGestureRecognizer> create();
    virtual ~PlatformGestureRecognizer();

    // Invoked for each touch event that could contribute to the current gesture.
    // Takes a PlatformTouchEvent and the EventHandler that originated it and which will also
    // be the target of any generated synthetic event. Finally, |handled|
    // specifies if the |event| was actually handled by |source| (by the JavaScript)
    // Returns true if the event resulted in firing a synthetic event.
    virtual bool processTouchEventForGesture(const PlatformTouchEvent&, EventHandler*, bool handled) = 0;
};

} // namespace WebCore

#endif // PlatformGestureRecognizer_h