Class OscilloscopeDispatcher


  • public class OscilloscopeDispatcher
    extends java.lang.Object
    This class keeps the oscilloscope animation running and is used to set various attributes of the scope.

    You need to provide an Oscilloscope widget by overriding the getOscilloscope() method. The Control.redraw() method will be called every getDelayLoop() milliseconds. The higher the value, the slower the animation will run.

    Just before the redraw and just after the redraw the hook..Draw methods are called. Don't do any expensive calculations there because this will slow down the animation.

    Then a counter is incremented and if the counter reaches the getPulse() value, then the hookSetValues(int) method is called. This is you opportunity to provide a value to the scope by calling its setValue or setValues method. The hookSetValues method is only called if the getPulse() value is greater than NO_PULSE

    You can also be called back by the widget if it runs out of values by setting a listener in the Oscilloscope#addStackListener(OscilloscopeStackAdapter) method.

    If you want to speed up the scope, try overriding the getProgression() method. This will draw the scope this number of times before actually painting.

    • Field Detail

      • BACKGROUND_MONITOR

        public static final int[] BACKGROUND_MONITOR
        Contains a small image that can serve as the background of the scope.
      • BACKGROUND_MONITOR_SMALL

        public static final int[] BACKGROUND_MONITOR_SMALL
        Contains a small image that can serve as the background of the scope.
      • backgroundImage

        private org.eclipse.swt.graphics.Image backgroundImage
      • channel

        private int channel
      • stop

        private boolean stop
      • isRunning

        private boolean isRunning
      • activeForegroundColor

        private org.eclipse.swt.graphics.Color activeForegroundColor
      • inactiveForegroundColor

        private org.eclipse.swt.graphics.Color inactiveForegroundColor
    • Constructor Detail

      • OscilloscopeDispatcher

        public OscilloscopeDispatcher​(int channel)
        Parameters:
        channel -
        See Also:
        getChannel()
      • OscilloscopeDispatcher

        public OscilloscopeDispatcher()
        The default constructor.
    • Method Detail

      • dispatch

        public void dispatch()
        This method will get the animation going. It will create a runnable that will be dispatched to the user interface thread. The runnable increments a counter that leads to the getPulse() value and if this is reached then the counter is reset. The counter is passed to the hook methods so that they can prepare for the next pulse.

        After the hook methods are called, the runnable is placed in the user interface thread with a timer of getDelayLoop() milliseconds. However, if the delay loop is set to 1, it will dispatch using Display.asyncExec(Runnable) for maximum speed.

        This method is not meant to be overridden, override init() hookBeforeDraw(Oscilloscope, int), hookAfterDraw(Oscilloscope, int) and hookPulse(Oscilloscope, int).

      • finalize

        protected void finalize()
                         throws java.lang.Throwable
        Overrides:
        finalize in class java.lang.Object
        Throws:
        java.lang.Throwable
      • getActiveForegoundColor

        public org.eclipse.swt.graphics.Color getActiveForegoundColor()
        Is used to get the color of the foreground when the thing that the scope is measuring is still alive. The aliveness of the thing that is being measured is returned by the isServiceActive() method. The result of this method will be used in the Control.setForeground(Color) method.
        Returns:
        the system color green.
        See Also:
        getInactiveForegoundColor(), getActiveForegoundColor(), setActiveForegoundColor(Color), Control.setForeground(Color)
      • setActiveForegoundColor

        public void setActiveForegoundColor​(org.eclipse.swt.graphics.Color color)
        Is used to get the color of the foreground when the thing that the scope is measuring is still alive. The aliveness of the thing that is being measured is returned by the isServiceActive() method. The result of this method will be used in the Control.setForeground(Color) method.
        Parameters:
        color - the new color.
        See Also:
        getInactiveForegoundColor(), getActiveForegoundColor(), getActiveForegoundColor()
      • getActiveSoundfile

        public java.io.File getActiveSoundfile()
        Override this to return a soundfile that will be played by the dispatcher in the hookPulse(Oscilloscope, int) method if the isSoundRequired() method returns true.
        Returns:
        null. Override to return a file that can be played by your sound hardware.
      • getBackgroundImage

        public org.eclipse.swt.graphics.Image getBackgroundImage()
        Override this to return the background image for the scope.
        Returns:
        the image stored in BACKGROUND_MONITOR. Override to supply your own Image.
      • createGridImage

        private org.eclipse.swt.graphics.Image createGridImage()
      • getBaseOffset

        public int getBaseOffset()
        Override this to set the offset of the scope line in percentages where 100 is the top of the widget and 0 is the bottom.
        Returns:
        Oscilloscope.BASE_CENTER which positions in the center. Override for other values.
      • stop

        public void stop()
        Will stop the animation.
      • getSoundClip

        public OscilloscopeDispatcher.SoundClip getSoundClip()
        Override this to return the Clip player.

        Overriding this method is not expected.

        Returns:
        the PlayClip object
      • getDelayLoop

        public int getDelayLoop()
        Override this to return a draw delay in milliseconds. The scope will progress getProgression() steps.
        Returns:
        30 milliseconds. Override with a smaller value for more speed.
      • getInactiveForegoundColor

        public org.eclipse.swt.graphics.Color getInactiveForegoundColor()
        Is used to get the color of the foreground when the thing that the scope is measuring is not active. The aliveness of the thing that is being measured is returned by the isServiceActive() method. The result of this method will be used in the Control.setForeground(Color) method.
        Returns:
        the system color red, override if you want to control the inactive foreground color
        See Also:
        setInactiveForegoundColor(Color), getActiveForegoundColor(), setActiveForegoundColor(Color), Control.setForeground(Color)
      • setInactiveForegoundColor

        public void setInactiveForegoundColor​(org.eclipse.swt.graphics.Color color)
        Is used to get the color of the foreground when the thing that the scope is measuring is still alive. The aliveness of the thing that is being measured is returned by the isServiceActive() method. The result of this method will be used in the Control.setForeground(Color) method.
        Parameters:
        color - the new color.
        See Also:
        getInactiveForegoundColor(), getActiveForegoundColor(), setActiveForegoundColor(Color), Control.setForeground(Color)
      • getInactiveSoundfile

        public java.io.File getInactiveSoundfile()
        Returns:
        this default implementation returns null
      • getLineWidth

        public int getLineWidth()
        Returns:
        this default implementation returns 1
      • getOscilloscope

        public Oscilloscope getOscilloscope()
        This method returns the Oscilloscope.
        Returns:
        the oscilloscope
      • isRunning

        public boolean isRunning()
        Returns:
        true if the dispatcher is running.
        See Also:
        dispatch(), stop()
      • setOscilloscope

        public void setOscilloscope​(Oscilloscope scope)
        This method sets the Oscilloscope.
        Parameters:
        scope -
      • getProgression

        public int getProgression()
        Override this to set the number of steps that is calculated before it is actually drawn on the display. This will make the graphic look more jumpy for slower/higher delay rates but you can win speed at faster/lower delay rates. There will be getProgression() values consumed so make sure that the value stack contains enough entries.

        If the getDelayLoop() is 10 and the getPulse() is 1 and the getProgression() is 5 then every 10 milliseconds the graph will have progressed 5 pixels. If you want to avoid gaps in your graph, you need to input 5 values every time you reach hookSetValues(int). If the getPulse() is 3, you need to input 15 values for a gapless graph. Alternatively, you can implement a stack listener in the scope to let it call you in case it runs out of values.

        Returns:
        1. Override and increment for more speed. Must be higher then zero.
      • getSteadyPosition

        public int getSteadyPosition()
        If the scope value must be drawn on a steady position then this method can supply a value.
        Returns:
        the default implementation returns 200
        See Also:
        Oscilloscope.setSteady(int, boolean, int)
      • getChannel

        public int getChannel()
        Returns the channel that this scope is the dispatcher for. Please note that you do not really need one dispatcher per channel.
        Returns:
        the channel for this dispatcher. Can be -1 if not set.
      • hookAfterDraw

        public void hookAfterDraw​(Oscilloscope oscilloscope,
                                  int counter)
        Is called just after the widget is redrawn every getDelayLoop() milliseconds. The pulse counter will be set to zero when it reaches getPulse().
        Parameters:
        oscilloscope -
        counter -
      • hookBeforeDraw

        public void hookBeforeDraw​(Oscilloscope oscilloscope,
                                   int counter)
        Is called just before the widget is redrawn every getDelayLoop() milliseconds. It will also call the hookChangeAttributes() method if the number of times this method is called matches the getPulse() value. The pulse counter will be set to zero when it reaches getPulse().

        If you override this method, don't forget to call hookChangeAttributes() every now and then.

        Parameters:
        oscilloscope -
        counter -
      • hookChangeAttributes

        public void hookChangeAttributes()
        This method sets the values in the scope by calling the individual value methods in the dispatcher. Be aware that this method actually calls some candy so you might want to call super.
      • hookPulse

        public void hookPulse​(Oscilloscope oscilloscope,
                              int pulse)
        This method is called every time the dispatcher reaches the getPulse() counter. This method plays the active or inactive sound if so required. If you do not want the sounds to play, either disable sounds by not overriding the isSoundRequired() method or override this method.
        Parameters:
        oscilloscope -
        pulse -
      • hookSetValues

        public void hookSetValues​(int pulse)
        This method will be called every getPulse() times the scope is redrawn which will occur every getDelayLoop() milliseconds (if your hardware is capable of doing so). The scope will progress one pixel every getDelayLoop() milliseconds and will draw the next value from the queue of the scope. If the scope is out of values it will progress one pixel without a value (draw a pixel at his center).

        If the delay loop is 10 and the pulse is 20, you have an opportunity to set a value in the scope every 200 milliseconds. In this time the scope will have progressed 20 pixels. If you supply 10 values by calling the setValue(int) 10 times or if you call the setValues(int[]) with 10 ints then you will see 10 pixels of movement and a straight line of 10 pixels.

        If the setPulse method is not overridden or if you supply NO_PULSE then this method will not be called unless you override the dispatch method (not recommended). To still set values in the scope you can set a stack listener in the widget that will be called when there are no more values in the stack. Alternatively you can set the return value of getPulse() to 1 so you have the opportunity to provide a value every cycle.

        Parameters:
        pulse -
        See Also:
        Oscilloscope#setValue(int), Oscilloscope#setValues(int[]), Oscilloscope#addStackListener(OscilloscopeStackAdapter)
      • init

        public void init()
        Will be called only once.
      • isPercentage

        public boolean isPercentage()
        Indicates if the value that comes in from the scope is a percentage rather than an absolute value.
        Returns:
        the default implementation returns true
        See Also:
        Oscilloscope.setPercentage(int, boolean)
      • isServiceActive

        public boolean isServiceActive()
        A helper method to indicate if something that you are measuring is active. Based on the output of this method things can be done, like playing a flat-line sound, changing the foreground color and such.
        Returns:
        the default implementation returns true
      • isSoundRequired

        public boolean isSoundRequired()
        The dispatcher is able to beep and pling and this method helps in indicating if this is required.
        Returns:
        this default implementation returns false
        See Also:
        Oscilloscope.setSteady(int, boolean, int)
      • updateBackgroundImage

        void updateBackgroundImage()