Fix curve color and style cycle

Author: PierreRaybaut

CHANGELOG.md

@@ -32,6 +32,12 @@ for future and past milestones.
 * Fixed [Issue #55](https://github.com/DataLab-Platform/DataLab/issues/55) - Changing image bounds in Image View has no effect on the associated image object properties
 * Fixed [Issue #56](https://github.com/DataLab-Platform/DataLab/issues/56) - "Test data" plugin: `AttributeError: 'NoneType' object has no attribute 'data'` when canceling "Create image with peaks"
 * Fixed [Issue #57](https://github.com/DataLab-Platform/DataLab/issues/57) - Circle and ellipse result shapes are not transformed properly
+* Curve color and style cycle:
+  * Before this release, this cycle was handled by the same mechanism either for the
+    Signal Panel or the HDF5 Browser, which was not the expected behavior
+  * Now, the cycle is handled separately: the HDF5 Browser or the Text Import
+    Wizard use always the same color and style for curves, and they don't interfere
+    with the Signal Panel cycle
 
 ## DataLab Version 0.12.0 ##
 

cdl/core/gui/panel/signal.py

@@ -29,7 +29,7 @@
 from cdl.core.gui.processor.signal import SignalProcessor
 from cdl.core.io.signal import SignalIORegistry
 from cdl.core.model.signal import (
-    CurveStyles,
+    CURVESTYLES,
     SignalObj,
     create_signal_from_param,
     new_signal_param,
@@ -136,4 +136,4 @@ def toggle_anti_aliasing(self, state: bool) -> None:
 
     def reset_curve_styles(self) -> None:
         """Reset curve styles"""
-        CurveStyles.reset_styles()
+        CURVESTYLES.reset_styles()

cdl/core/model/signal.py

@@ -14,8 +14,9 @@
 
 from __future__ import annotations
 
+from contextlib import contextmanager
 from copy import deepcopy
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Generator
 from uuid import uuid4
 
 import guidata.dataset as gds
@@ -52,27 +53,42 @@ class CurveStyles:
     )
     LINESTYLES = ("SolidLine", "DashLine", "DashDotLine", "DashDotDotLine")
 
-    def style_generator():  # pylint: disable=no-method-argument
+    def __init__(self) -> None:
+        self.__suspend = False
+        self.curve_style = self.style_generator()
+
+    @staticmethod
+    def style_generator() -> Generator[tuple[str, str], None, None]:
         """Cycling through curve styles"""
         while True:
             for linestyle in CurveStyles.LINESTYLES:
                 for color in CurveStyles.COLORS:
                     yield (color, linestyle)
 
-    CURVE_STYLE = style_generator()
-
-    @classmethod
-    def apply_style(cls, param: CurveParam):
+    def apply_style(self, param: CurveParam) -> None:
         """Apply style to curve"""
-        color, linestyle = next(cls.CURVE_STYLE)
+        if self.__suspend:
+            # Suspend mode: always apply the first style
+            color, linestyle = CurveStyles.COLORS[0], CurveStyles.LINESTYLES[0]
+        else:
+            color, linestyle = next(self.curve_style)
         param.line.color = color
         param.line.style = linestyle
         param.symbol.marker = "NoSymbol"
 
-    @classmethod
-    def reset_styles(cls):
+    def reset_styles(self) -> None:
         """Reset styles"""
-        cls.CURVE_STYLE = cls.style_generator()
+        self.curve_style = self.style_generator()
+
+    @contextmanager
+    def suspend(self) -> Generator[None, None, None]:
+        """Suspend style generator"""
+        self.__suspend = True
+        yield
+        self.__suspend = False
+
+
+CURVESTYLES = CurveStyles()  # This is the unique instance of the CurveStyles class
 
 
 class ROIParam(gds.DataSet):
@@ -316,7 +332,7 @@ def make_item(self, update_from: CurveItem = None) -> CurveItem:
             elif len(self.xydata) == 4:  # x, y, dx, dy error bar signal
                 x, y, dx, dy = self.xydata
                 item = make.merror(x.real, y.real, dx.real, dy.real, label=self.title)
-            CurveStyles.apply_style(item.param)
+            CURVESTYLES.apply_style(item.param)
         else:
             raise RuntimeError("data not supported")
         if update_from is None:

cdl/tests/scenarios/demo.py

@@ -30,7 +30,6 @@
     get_test_image,
 )
 from cdl.tests.features.common.roi_app import create_test_image_with_roi
-from cdl.widgets import fitdialog
 
 if TYPE_CHECKING:  # pragma: no cover
     from cdl.core.gui.main import CDLMainWindow

cdl/widgets/h5browser.py

@@ -30,7 +30,7 @@
 
 from cdl.config import _
 from cdl.core.io.h5 import H5Importer
-from cdl.core.model.signal import CurveStyles
+from cdl.core.model.signal import CURVESTYLES
 from cdl.env import execenv
 from cdl.obj import ImageObj, SignalObj
 from cdl.utils.qthelpers import qt_handle_error_message
@@ -402,11 +402,11 @@ def update_plot_preview(self, node: BaseNode) -> None:
         if isinstance(obj, SignalObj):
             obj: SignalObj
             widget = self.curvewidget
-            CurveStyles.reset_styles()
         else:
             obj: ImageObj
             widget = self.imagewidget
-        item = obj.make_item()
+        with CURVESTYLES.suspend():
+            item = obj.make_item()
         plot = widget.get_plot()
         plot.del_all_items()
         plot.add_item(item)

cdl/widgets/textimport.py

@@ -36,7 +36,7 @@
 from qtpy.compat import getopenfilename
 
 from cdl.config import Conf, _
-from cdl.core.model.signal import CurveStyles
+from cdl.core.model.signal import CURVESTYLES
 from cdl.obj import ImageObj, SignalObj, create_image, create_signal
 from cdl.utils.qthelpers import create_progress_bar, save_restore_stds
 from cdl.widgets.wizard import Wizard, WizardPage
@@ -476,12 +476,12 @@ def initialize_page(self) -> None:
         plot = self.plot_widget.get_plot()
         plot.del_all_items()
         if self.destination == "signal":
-            CurveStyles.reset_styles()
             xydata = data.T
             x = np.arange(len(xydata[0]))
             if len(xydata) == 1:
                 obj = create_signal("", x=x, y=xydata[0])
-                item = obj.make_item()
+                with CURVESTYLES.suspend():
+                    item = obj.make_item()
                 plot.add_item(item)
                 self.__objitmlist = [(obj, item)]
             else:
@@ -497,7 +497,8 @@ def initialize_page(self) -> None:
                             break
                         yidx = ycol if param.first_col_is_x else ycol - 1
                         obj = create_signal("", x=x, y=xydata[yidx])
-                        item = obj.make_item()
+                        with CURVESTYLES.suspend():
+                            item = obj.make_item()
                         plot.add_item(item)
                         self.__objitmlist.append((obj, item))
                         QW.QApplication.processEvents()