add context menu actions to set range start and end

src/ui/rangeslider.py

@@ -7,8 +7,10 @@ from PySide6.QtCore import QRect, QPoint, Signal
 from PySide6.QtGui import QPainter, Qt
 from PySide6.QtWidgets import QWidget
 
+from src.pluginregistry import PluginRegistry
+from src.util import conversion
 from src.util.color import to_qcolor
-
+from src.i18n import _
 
 class RangeSliderHandle():
     def __init__(self, value: int):
@@ -27,7 +29,13 @@ class UpdateStyle(Enum):
 
 
 class RangeSlider(QWidget):
-    value_changed = Signal(float, float)
+    value_changed = Signal(str, str)
+    """Signal emitted when the range slider value changes. 
+        **Note**: The value is a string and must be parsed into an int. 
+        QT's signal api only supports 32bit integers. Ints larger 
+        than 2**32-1 will overflow. Probably because there is some C/C++
+        code involved. We work around this by converting the python int 
+        into a string."""
 
     _width = 20
     _handle_width = 12
@@ -42,11 +50,22 @@ class RangeSlider(QWidget):
         self.max_value = 100
 
         self.lower_value = RangeSliderHandle(0)
-        self.upper_value = RangeSliderHandle(100)
+        self.upper_value = RangeSliderHandle(self.max_value)
 
         self.selected_handle = None
         self.selection_drag_range = (self.min_value, self.max_value)
 
+    def set_maximum(self, max: int):
+        if self.max_value == max:
+            return
+        was_at_max = self.upper_value.value == self.max_value
+
+        self.max_value = max
+
+        if was_at_max:
+            self.upper_value.value = max
+            self._emit_value_changed()
+
     def paintEvent(self, event: PySide6.QtGui.QPaintEvent) -> None:
         painter = QPainter(self)
         self._draw_background(painter)
@@ -104,13 +123,13 @@ class RangeSlider(QWidget):
         painter.drawEllipse(QPoint(self._width / 2, y_pixel), self._handle_width / 2 - 1, self._handle_width / 2 - 1)
 
     def _value_to_pixel(self, value: int) -> int:
-        value_percent = value / (self.max_value - self.min_value)
+        value_percent = value / self.max_value
         pixel = (self.height() - 2 * self._handle_width) * value_percent + self._handle_width
         return pixel
 
     def _pixel_to_value(self, pixel: int) -> int:
         pixel_percent = (pixel - self._handle_width) / (self.height() - 2 * self._handle_width)
-        return (self.max_value - self.min_value) * pixel_percent
+        return int(math.floor(self.max_value * pixel_percent))
 
     def _is_on_handle(self, handle: RangeSliderHandle, y_pixel: int, direction=1) -> bool:
         handle_y_pixel = self._value_to_pixel(handle.value)
@@ -139,5 +158,28 @@ class RangeSlider(QWidget):
             if self.selection_drag_range[0] <= value <= self.selection_drag_range[1]:
                 self.selected_handle.value = value
                 # print("%s, %s" %(self.lower_value.value, self.upper_value.value))
-                self.value_changed.emit(self.lower_value.value, self.upper_value.value)
+                self._emit_value_changed()
                 self.update()
+                self._update_tooltip()
+
+    def set_range_start(self, value: int):
+        self.lower_value.value = value
+        self._emit_value_changed()
+        self.update()
+
+    def set_range_end(self, value: int):
+        self.upper_value.value = value
+        self._emit_value_changed()
+        self.update()
+
+    def _emit_value_changed(self):
+        # print(f"emit {str(self.lower_value.value)}, {str(self.upper_value.value)}")
+        self.value_changed.emit(str(self.lower_value.value), str(self.upper_value.value))
+
+    def _update_tooltip(self):
+        text = _("showing bytes {0} to {1} ({2})").format(
+            self.lower_value.value,
+            self.upper_value.value,
+            conversion.humanbytes(self.upper_value.value - self.lower_value.value))
+        PluginRegistry.execute("update_status_bar", text)
+        self.setToolTip(text)