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gtkgtk#

GTK (GTK#) TreeView, make gridlines more visible?

I enabled gridlines like below.

        tree.EnableGridLines = TreeViewGridLines.Both;

But the problem is the lines are barely visible like below (if you think there are no gridlines, zoom the image, and look really hard). Gtk.TreeView had GridLineWidth, but it was read-only. How can I make them more visible?

enter image description here

I have tried to find C# equivalent of the answer's C code and the following worked. Making the gridlines thicker worked but the problem was that in Ubuntu, the colour of the gridline is too light that it was not really visible even it it were thicker. So, I changed the colour instead.

var p = new CssProvider();
p.LoadFromData("*{border-color:darkgray;}");
tree.StyleContext.AddProvider(p,Gtk.StyleProviderPriority.Application);

enter image description here

Solution

  • You could use a CSS provider and set the grid line width to a larger value than one pixel. Again, the following code snippets are written in "C"; however, it should be easy enough to interpret the code to use equivalent C# statements.

    First, off one would create a GTK CSS provider.

    GtkCssProvider      *provider;
provider = gtk_css_provider_new();

    Then, the customized CSS style information would be defined for the CSS provider widget and the CSS provider widget would be associated with your tree view.

    gtk_css_provider_load_from_data(provider, "*{-GtkTreeView-grid-line-width: 4;}", -1, NULL);
gtk_style_context_add_provider(gtk_widget_get_style_context(view), GTK_STYLE_PROVIDER(provider), GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);

    Note that GTK defines a specific set of attributes for grid elements as opposed to using a standard element such as "border-width". The attribute needing customization in this scenario is "-GtkTreeView-grid-line-width".

    Having set the grid width to an exaggerated width of four pixels, the following sample illustrates the effect of the custom CSS style enhancement.

    Tree View with Thick Grid Lines

    I hope that points you in the correct direction.

    Regards.