def _draw_bar_picture(self, ix: int, bar: BarData) -> QtGui.QPicture:
""""""
# Create objects
volume_picture = QtGui.QPicture()
painter = QtGui.QPainter(volume_picture)
# Set painter color
if bar.close_price >= bar.open_price:
painter.setPen(self._up_pen)
painter.setBrush(self._up_brush)
else:
painter.setPen(self._down_pen)
painter.setBrush(self._down_brush)
# Draw volume body
rect = QtCore.QRectF(
ix - BAR_WIDTH,
0,
BAR_WIDTH * 2,
bar.volume
)
painter.drawRect(rect)
# Finish
painter.end()
return volume_picture
def _draw_item_picture(self, min_ix: int, max_ix: int) -> None:
"""
Draw the picture of item in specific range.
"""
self._item_picuture = QtGui.QPicture()
painter = QtGui.QPainter(self._item_picuture)
for n in range(min_ix, max_ix):
bar_picture = self._bar_picutures[n]
bar_picture.play(painter)
painter.end()
def _draw_bar_picture(self, ix: int, bar: BarData) -> QtGui.QPicture:
""""""
# Create objects
candle_picture = QtGui.QPicture()
painter = QtGui.QPainter(candle_picture)
# Set painter color
if bar.close_price >= bar.open_price:
painter.setPen(self._up_pen)
painter.setBrush(self._black_brush)
else:
painter.setPen(self._down_pen)
painter.setBrush(self._down_brush)
# Draw candle shadow
if bar.high_price > bar.low_price:
painter.drawLine(
QtCore.QPointF(ix, bar.high_price),
QtCore.QPointF(ix, bar.low_price)
)
# Draw candle body
if bar.open_price == bar.close_price:
painter.drawLine(
QtCore.QPointF(ix - BAR_WIDTH, bar.open_price),
QtCore.QPointF(ix + BAR_WIDTH, bar.open_price),
)
else:
rect = QtCore.QRectF(
ix - BAR_WIDTH,
bar.open_price,
BAR_WIDTH * 2,
bar.close_price - bar.open_price
)
painter.drawRect(rect)
# Finish
painter.end()
return candle_picture