reset zoom_marker1_shown when replotting

close #130 (closed)

sohstationviewer/view/plotting/plotting_widget/multi_threaded_plotting_widget.py

@@ -74,7 +74,7 @@ class MultiThreadedPlottingWidget(PlottingWidget):
         :param time_ticks_total: max number of tick to show on time bar
         :param is_waveform: True if this is a WaveformWidget, otherwise False
         """
-
+        self.zoom_marker1_shown = False
         self.key = key
         self.processing_log = []  # [(message, type)]
         self.gap_bar = None