Source code for TermTk.TTkAbstract.abstractscrollarea
# MIT License
#
# Copyright (c) 2021 Eugenio Parodi <ceccopierangiolieugenio AT googlemail DOT com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
__all__ = ['TTkAbstractScrollArea']
from TermTk.TTkCore.constant import TTkK
# from TermTk.TTkCore.log import TTkLog
from TermTk.TTkCore.signal import pyTTkSlot
from TermTk.TTkWidgets.widget import TTkWidget
from TermTk.TTkWidgets.container import TTkContainer
from TermTk.TTkWidgets.scrollbar import TTkScrollBar
from TermTk.TTkLayouts.gridlayout import TTkGridLayout
from TermTk.TTkAbstract.abstractscrollview import TTkAbstractScrollViewInterface
[docs]class TTkAbstractScrollArea(TTkContainer):
__slots__ = (
'_processing', # this flag is required to avoid unnecessary loop on edge cases
'_viewport',
'_verticalScrollBar', '_verticalScrollBarPolicy',
'_horizontalScrollBar', '_horizontalScrollBarPolicy',)
def __init__(self, *args, **kwargs):
self._processing = False
self._viewport = None
# self.setLayout(TTkGridLayout())
self._verticalScrollBar = TTkScrollBar(orientation=TTkK.VERTICAL, visible=False)
self._horizontalScrollBar = TTkScrollBar(orientation=TTkK.HORIZONTAL, visible=False)
self._verticalScrollBarPolicy = kwargs.get("verticalScrollBarPolicy", TTkK.ScrollBarAsNeeded)
self._horizontalScrollBarPolicy = kwargs.get("horizontalScrollBarPolicy",TTkK.ScrollBarAsNeeded)
super().__init__(*args, **kwargs)
self.layout().addWidget(self._verticalScrollBar)
self.layout().addWidget(self._horizontalScrollBar)
def _resizeEvent(self):
if self._processing: return
self._processing = True
w,h = self.size()
vert = 1 if self._verticalScrollBar.isVisible() else 0
hori = 1 if self._horizontalScrollBar.isVisible() else 0
if vert:
self._verticalScrollBar.setGeometry(w-1,0,1,h-hori)
if hori:
self._horizontalScrollBar.setGeometry(0,h-1,w-vert,1)
if self._viewport:
self._viewport.setGeometry(0,0,w-vert,h-hori)
self._processing = False
@pyTTkSlot()
def _viewportChanged(self):
if not self.isVisible(): return
w,h = self.size()
fw, fh = self._viewport.viewFullAreaSize()
dw, dh = self._viewport.viewDisplayedSize()
ox, oy = self._viewport.getViewOffsets()
if 0 in [fw,fh,dw,dh]:
return
hpage = dw
vpage = dh
hrange = fw - dw
vrange = fh - dh
# TTkLog.debug(f"f:{fw,fh=}, d:{dw,dh=}, o:{ox,oy=}")
self._verticalScrollBar.setPageStep(vpage)
self._verticalScrollBar.setRange(0, vrange)
self._verticalScrollBar.setValue(oy)
self._horizontalScrollBar.setPageStep(hpage)
self._horizontalScrollBar.setRange(0, hrange)
self._horizontalScrollBar.setValue(ox)
if self._verticalScrollBarPolicy == TTkK.ScrollBarAsNeeded:
if h<=4 or w<=1 or vrange<=0:
self._verticalScrollBar.hide()
elif dh>self._verticalScrollBar.minimumHeight()+1:
# we need enough space to display the bar to avoid endless loop
self._verticalScrollBar.show()
elif self._verticalScrollBarPolicy == TTkK.ScrollBarAlwaysOn:
self._verticalScrollBar.show()
else:
self._verticalScrollBar.hide()
if self._horizontalScrollBarPolicy == TTkK.ScrollBarAsNeeded:
if w<=4 or h<=1 or hrange<=0:
self._horizontalScrollBar.hide()
elif dw>self._horizontalScrollBar.minimumWidth()+1:
# we need enough space to display the bar to avoid endless loop
self._horizontalScrollBar.show()
elif self._horizontalScrollBarPolicy == TTkK.ScrollBarAlwaysOn:
self._horizontalScrollBar.show()
else:
self._horizontalScrollBar.hide()
self._resizeEvent()
@pyTTkSlot(int)
def _vscrollMoved(self, val):
ox, _ = self._viewport.getViewOffsets()
self._viewport.viewMoveTo(ox, val)
@pyTTkSlot(int)
def _hscrollMoved(self, val):
_, oy = self._viewport.getViewOffsets()
self._viewport.viewMoveTo(val, oy)
def setViewport(self, viewport):
if not isinstance(viewport, TTkAbstractScrollViewInterface):
raise TypeError("TTkAbstractScrollViewInterface is required in TTkAbstractScrollArea.setVewport(viewport)")
if self._viewport:
self._viewport.viewChanged.disconnect(self._viewportChanged)
# TODO: Remove this check once
# unified "addWidget" and "addItem" in the TTKGridLayout
if isinstance(viewport, TTkWidget):
self.layout().removeWidget(self._viewport)
else:
self.layout().removeItem(self._viewport)
self._viewport = viewport
self._viewport.viewChanged.connect(self._viewportChanged)
self._verticalScrollBar.sliderMoved.connect(self._vscrollMoved)
self._horizontalScrollBar.sliderMoved.connect(self._hscrollMoved)
# TODO: Remove this check once
# unified "addWidget" and "addItem" in the TTKGridLayout
if isinstance(viewport, TTkWidget):
self.layout().addWidget(viewport)
else:
self.layout().addItem(viewport)
self._resizeEvent()
def setVerticalScrollBarPolicy(self, policy):
if policy != self._verticalScrollBarPolicy:
self._verticalScrollBarPolicy = policy
self._viewportChanged()
def setHorizontalScrollBarPolicy(self, policy):
if policy != self._horizontalScrollBarPolicy:
self._horizontalScrollBarPolicy = policy
self._viewportChanged()
def viewport(self):
return self._viewport
def update(self, repaint=True, updateLayout=False, updateParent=False):
if self._viewport:
self._viewport.update(repaint, updateLayout, updateParent=False)
return super().update(repaint, updateLayout, updateParent)