class LUIScrollableRegion(LUIObject):
""" Scrollable region, reparent elements to the .content_node to make them
scroll. """
def __init__(self,
parent=None,
width=100,
height=100,
padding=10,
**kwargs):
LUIObject.__init__(self)
self.set_size(width, height)
self._content_parent = LUIObject(self)
self._content_parent.set_size("100%", "100%")
self._content_parent.clip_bounds = (0, 0, 0, 0)
self._content_clip = LUIObject(self._content_parent,
x=padding,
y=padding)
self._content_clip.set_size("100%", "100%")
self._content_scroller = LUIObject(self._content_clip)
self._content_scroller.width = "100%"
self._scrollbar = LUIObject(self, x=0, y=0, w=20)
self._scrollbar.height = "100%"
self._scrollbar.right = -10
self._scrollbar_bg = LUISprite(self._scrollbar, "blank", "skin")
self._scrollbar_bg.color = (1, 1, 1, 0.05)
self._scrollbar_bg.set_size(3, "100%")
self._scrollbar_bg.center_horizontal = True
# Handle
self._scrollbar_handle = LUIObject(self._scrollbar, x=5, y=0, w=10)
self._scroll_handle_top = LUISprite(self._scrollbar_handle,
"ScrollbarHandle_Top", "skin")
self._scroll_handle_mid = LUISprite(self._scrollbar_handle,
"ScrollbarHandle", "skin")
self._scroll_handle_bottom = LUISprite(self._scrollbar_handle,
"ScrollbarHandle_Bottom",
"skin")
self._scrollbar_handle.solid = True
self._scrollbar.solid = True
self._scrollbar_handle.bind("mousedown", self._start_scrolling)
self._scrollbar_handle.bind("mouseup", self._stop_scrolling)
self._scrollbar.bind("mousedown", self._on_bar_click)
self._scrollbar.bind("mouseup", self._stop_scrolling)
self._handle_dragging = False
self._drag_start_y = 0
self._scroll_top_position = 0
self._content_height = 400
scroll_shadow_width = self.width - 10
# Scroll shadow
self._scroll_shadow_top = LUIHorizontalStretchedLayout(
parent=self, prefix="ScrollShadowTop", width="100%")
self._scroll_shadow_bottom = LUIHorizontalStretchedLayout(
parent=self, prefix="ScrollShadowBottom", width="100%")
self._scroll_shadow_bottom.bottom = 0
self._handle_height = 100
if parent is not None:
self.parent = parent
LUIInitialState.init(self, kwargs)
self.content_node = self._content_scroller
taskMgr.doMethodLater(0.05, lambda task: self._update(),
"update_scrollbar")
def _on_bar_click(self, event):
""" Internal handler when the user clicks on the scroll bar """
self._scroll_to_bar_pixels(event.coordinates.y -
self._scrollbar.abs_pos.y -
self._handle_height / 2.0)
self._update()
self._start_scrolling(event)
def _start_scrolling(self, event):
""" Internal method when we start scrolling """
self.request_focus()
if not self._handle_dragging:
self._drag_start_y = event.coordinates.y
self._handle_dragging = True
def _stop_scrolling(self, event):
""" Internal handler when we should stop scrolling """
if self._handle_dragging:
self._handle_dragging = False
self.blur()
def _scroll_to_bar_pixels(self, pixels):
""" Internal method to convert from pixels to a relative position """
offset = pixels * self._content_height / self.height
self._scroll_top_position = offset
self._scroll_top_position = max(
0,
min(self._content_height - self._content_clip.height,
self._scroll_top_position))
def on_tick(self, event):
""" Internal on tick handler """
if self._handle_dragging:
scroll_abs_pos = self._scrollbar.abs_pos
clamped_coord_y = max(
scroll_abs_pos.y,
min(scroll_abs_pos.y + self.height, event.coordinates.y))
offset = clamped_coord_y - self._drag_start_y
self._drag_start_y = clamped_coord_y
self._scroll_to_bar_pixels(self._scroll_top_position /
self._content_height * self.height +
offset)
self._update()
def _set_handle_height(self, height):
""" Internal method to set the scrollbar height """
self._scroll_handle_mid.top = float(self._scroll_handle_top.height)
self._scroll_handle_mid.height = max(
0.0, height - self._scroll_handle_top.height -
self._scroll_handle_bottom.height)
self._scroll_handle_bottom.top = self._scroll_handle_mid.height + self._scroll_handle_mid.top
self._handle_height = height
def _update(self):
""" Internal method to update the scroll bar """
self._content_height = max(1, self._content_scroller.get_height() + 20)
self._content_scroller.top = -self._scroll_top_position
scrollbar_height = max(
0.1, min(1.0, self._content_clip.height / self._content_height))
scrollbar_height_px = scrollbar_height * self.height
self._set_handle_height(scrollbar_height_px)
self._scrollbar_handle.top = self._scroll_top_position / self._content_height * self.height
top_alpha = max(0.0, min(1.0, self._scroll_top_position / 50.0))
bottom_alpha = max(
0.0,
min(1.0, (self._content_height - self._scroll_top_position -
self._content_clip.height) / 50.0))
self._scroll_shadow_top.color = (1, 1, 1, top_alpha)
self._scroll_shadow_bottom.color = (1, 1, 1, bottom_alpha)
if self._content_height <= self.height:
self._scrollbar_handle.hide()
else:
self._scrollbar_handle.show()
def on_element_added(self):
taskMgr.doMethodLater(0.05, lambda task: self._update(),
"update_layout")
def get_scroll_percentage(self):
""" Returns the current scroll height in percentage from 0 to 1 """
return self._scroll_top_position / max(
1, self._content_height - self._content_clip.height)
def set_scroll_percentage(self, percentage):
""" Sets the scroll position in percentage, 0 means top and 1 means bottom """
percentage = max(0.0, min(1.0, percentage))
pixels = max(
0.0, self._content_height - self._content_clip.height) * percentage
self._scroll_top_position = pixels
self._update()
scroll_percentage = property(get_scroll_percentage, set_scroll_percentage)
def scroll_to_bottom(self):
""" Scrolls to the bottom of the frame """
taskMgr.doMethodLater(0.07,
lambda task: self.set_scroll_percentage(1.0),
"scroll_to_bottom")
def scroll_to_top(self):
""" Scrolls to the top of the frame """
taskMgr.doMethodLater(0.07,
lambda task: self.set_scroll_percentage(0.0),
"scroll_to_top")
