wxGrid:: AutoSizing row when Column width is changed

wxPython Users
1

Hi,

I am using virtual grid for displaying data with custom render for auto wrapping the cell content when grid size changes.

I have added auto sizing of row in Custom Cell Render to display complete Cell content whenever Column size is changed. Auto sizing Rows seems to be very expensive when tried with huge data. This causing rendering of grid very slow or lagged.

Is there more efficient way to adjust row size to show complete cell contents? I tried adding logic to track old row height and auto size row only when there is change in it, but wasn’t that effective.

Any pointers are welcomed. Thanks in advance.

Thanks,

Saurabh

Snippet of my CustomGriCellAutoWrapStringRender:

Derived from http://markmail.org/download.xqy?id=6khc4r6w7c43vv3e&number=1

class CustomGridCellAutoWrapStringRenderer(wx.grid.PyGridCellRenderer):

def __init__(self):

    wx.grid.PyGridCellRenderer.__init__(self)

    self.rowHight = {}

    

def Draw(self, grid, attr, dc, rect, row, col, isSelected):

    text = grid.GetCellValue(row, col)

    dc.SetFont(attr.GetFont())

    curColSize = grid.GetColSize(col)

    text = wordwrap.wordwrap(text, curColSize, dc, breakLongWords=True)

    hAlign, vAlign = attr.GetAlignment()

    if isSelected:

        bg = grid.GetSelectionBackground()

        fg = grid.GetSelectionForeground()

    else:

        bg = attr.GetBackgroundColour()

        fg = attr.GetTextColour()

    dc.SetTextBackground(bg)

    dc.SetTextForeground(fg)

    dc.SetBrush(wx.Brush(bg, wx.SOLID))

    dc.SetPen(wx.TRANSPARENT_PEN)

    dc.DrawRectangleRect(rect)

    grid.DrawTextRectangle(dc, text, rect, hAlign, vAlign)

    wrapped_hight = dc.GetMultiLineTextExtent(text)[1]

    if wrapped_hight != self.rowHight.get(row, 0):

        grid.AutoSizeRow(row)

    self.rowHight[row] = max(wrapped_hight, self.rowHight.get(row, 0))
2

Saurabh Bhandiwad wrote:

Hi,

I am using virtual grid for displaying data with custom render for auto
wrapping the cell content when grid size changes.

I have added auto sizing of row in Custom Cell Render to display
complete Cell content whenever Column size is changed. Auto sizing Rows
seems to be very expensive when tried with huge data. This causing
rendering of grid very slow or lagged.

Is there more efficient way to adjust row size to show complete cell
contents? I tried adding logic to track old row height and auto size row
only when there is change in it, but wasn't that effective.

Any pointers are welcomed. Thanks in advance.

One approach would be to never use the built-in autosize methods and manage it all yourself. For example your renderer could check the size needed when drawing the contents of a cell, and if the best width or height is larger than the current then resize the col or row to accommodate that size. That would mean that you would only be autosized to larger sizes, not smaller, but that may be good enough for most cases.

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Robin Dunn
Software Craftsman