057. How to display tooltips in GtkTreeView - Part 2?

Problem

You have displayed tooltips for items in a treeview in Part 1.

However, the toolstips get displayed in the column headers too. Also, the tooltip does not disappear if you move the mouse out from the treeview from the top. You would like to fix these as shown below:

How to display tooltips in GtkTreeView - Part 2?


Solution

  • The tooltips get displayed in the column headers because function on_enter($view, $event) continues to give x and y in the column header.
  • In order to know if the mouse is in the column header region, we make use of another function GtkWidget::get_pointer()

Sample Code

1   
2   
3   
4   
5   
6   
7   
8   
9   
10   
11   
12   
13   
14   
15   
16   
17   
18   
19   
20   
21   
22   
23   
24   
25   
26   
27   
28   
29   
30   
31   
35   
36   
37   
38   
39   
40   
41   
42   
43   
44   
45   
47   
48   
49   
50   
51   
52   
53   
54   
55   
56   
57   
58   
59   
60   
61   
62   
63   
65   
67   
69   
70   
71   
72   
74   
75   
76   
77   
78   
79   
80   
81   
83   
84   
85   
87   
90   
96   
101   
102   
103   
104   
105   
108   
109   
110   
111   
113   
114   
115   
120   
121   
122   
123   
124   
125   
126   
127   
128   
129   
130   
131   
132   
133   
134   
135   
136   
137   
138   
139   
140   
141   
142   
143   
144   
145   
146   
147   
148   
149   
150   
151   
152   
153   
154   
155   
156   
157   
158   
159   
160   
161   
162   
163   
164   
165   
166   
167   
168   
169   
170   
171   
172   
176   
177   
178   
179   
180   
181   
182   
183   
184   
185   
186   
187   
188   
189   
190   
191   
192   
193   
194   
195   
196   
197   
198   
199   
200   
201   
202   
203   
204   
205   
206   
207   
208   
209   
210   
211   
212   
213   
214   
<?php
$window = new GtkWindow();
$window->set_size_request(400, 200);
$window->connect_simple('destroy', array('Gtk','main_quit'));
$window->add($vbox = new GtkVBox());

// display title
$title = new GtkLabel("Display tooltips in a GtkTreeView - Part 2");
$title->modify_font(new PangoFontDescription("Times New Roman Italic 10"));
$title->modify_fg(Gtk::STATE_NORMAL, GdkColor::parse("#0000ff"));
$title->set_size_request(-1, 40);
$vbox->pack_start($title, 0, 0);
$vbox->pack_start(new GtkLabel(''), 0, 0); // add a small gap

// Set up treeview
$data = array(
    array('row0', 'item 42', 2, 3.1),
    array('row1', 'item 36', 20, 6.21),
    array('row2', 'item 21', 8, 9.36),
    array('row3', 'item 10', 11, 12.4),
    array('row4', 'item 7', 5, 15.5),
    array('row5', 'item 4', 17, 18.6),
    array('row6', 'item 3', 20, 21.73));

$view1 = display_table ($vbox, $data);

$window->show_all();
Gtk::main();

// the class to display tooltips in treeview
class TreeviewTooltips {

    function TreeviewTooltips($view) {
        // create the tooltip window
        $this->tooltip_window = new GtkWindow(Gtk::WINDOW_POPUP);
        $this->tooltip_window->set_name('gtk-tooltips');
        $this->tooltip_window->set_resizable(False);
        $this->tooltip_window->set_border_width(4);
        $this->tooltip_window->set_app_paintable(True);
        $this->tooltip_window->connect('expose-event',
            array(&$this, 'on_expose_event'));

        $label = new GtkLabel('');
        $label->set_line_wrap(True);
        $label->set_alignment(0.5, 0.5);
        $label->set_use_markup(True);
        $label->show();
        $this->tooltip_window->add($label);

        $this->set_view($view);
        $this->hidden = 1;
    }

    function set_view($view) {
        $view->connect('motion-notify-event', array(&$this, 'on_motion'));
        $view->connect('leave-notify-event', array(&$this, 'on_leave'));
    }

    function on_motion($view, $event) {
        $scroll_win_pos = $view->get_pointer(); // note 1
        if ($scroll_win_pos[1]<=25) { // note 2
            $this->tooltip_window->hide(); // yes, hide it
            $this->hidden = 1;
            return true;
        } else {
            if ($this->hidden) $this->tooltip_window->show(); // no, show it
            $this->hidden = 0;
        }

        $path_array = $view->get_path_at_pos($event->x, $event->y);

        if (count($path_array)==0) return true; // note 3

        $path = $path_array[0][0];
        $col = $path_array[1];
        $col_title = $col->get_title();

        if ($col!=null) {
            $size = $this->tooltip_window->size_request();
            // set the location of the tooltip
            $this->tooltip_window->move($event->x_root - $size->width/2,
                $event->y_root + 12);
            $this->tooltip_window->child->set_text("row $path col $col_title");
            $this->tooltip_window->show();
        }
    }

    function on_leave($view, $event) {
        $this->tooltip_window->hide();
    }

    function on_expose_event($tooltip_window, $event) {
        $size = $tooltip_window->size_request();
        $tooltip_window->style->paint_flat_box($tooltip_window->window,
            Gtk::STATE_NORMAL,
        Gtk::SHADOW_OUT, null, $tooltip_window, 'tooltip', 0, 0,
            $size->width, $size->height);
    }
}

function display_table($vbox, $data) {

    // Set up a scroll window
    $scrolled_win = new GtkScrolledWindow();
    $scrolled_win->set_policy( Gtk::POLICY_AUTOMATIC,
        Gtk::POLICY_AUTOMATIC);
    $vbox->pack_start($scrolled_win);

    // Creates the list store
    if (defined("GObject::TYPE_STRING")) {
        $model = new GtkListStore(GObject::TYPE_STRING, GObject::TYPE_STRING,
                GObject::TYPE_LONG, GObject::TYPE_DOUBLE);
    } else {
        $model = new GtkListStore(Gtk::TYPE_STRING, Gtk::TYPE_STRING,
                    Gtk::TYPE_LONG, Gtk::TYPE_DOUBLE);
    }
    $field_header = array('Row #', 'Description', 'Qty', 'Price');
    $field_justification = array(0.5, 0.0, 0.5, 1.0);

    // Creates the view to display the list store
    $view = new GtkTreeView($model);
    $scrolled_win->add($view);

    // Creates the columns
    for ($col=0; $col<count($field_header); ++$col) {
        $cell_renderer = new GtkCellRendererText();
        $cell_renderer->set_property("xalign", $field_justification[$col]);
        $column = new GtkTreeViewColumn($field_header[$col],
            $cell_renderer, 'text', $col);
        $column->set_alignment($field_justification[$col]);
        $column->set_sort_column_id($col);

        // set the header font and color
        $label = new GtkLabel($field_header[$col]);
        $label->modify_font(new PangoFontDescription("Arial Bold"));
        $label->modify_fg(Gtk::STATE_NORMAL, GdkColor::parse("#0000FF"));
        $column->set_widget($label);
        $label->show();

        // setup self-defined function to display alternate row color
        $column->set_cell_data_func($cell_renderer, "format_col", $col);
        $view->append_column($column);
    }
    $tooltips = new TreeviewTooltips($view); // setup tooltip

    // pupulates the data
    for ($row=0; $row<count($data); ++$row) {
        $values = array();
        for ($col=0; $col<count($data[$row]); ++$col) {
            $values[] = $data[$row][$col];
        }
        $model->append($values);
    }

    // setup selection
    $selection = $view->get_selection();
    $selection->connect('changed', 'on_selection');
    return $view;
}

// display alternate row color
function format_col($column, $cell, $model, $iter, $col_num) {
    $path = $model->get_path($iter); // get the current path
    $row_num = $path[0]; // get the row number
    if ($col_num==3) {
        $amt = $model->get_value($iter, 3);
        $cell->set_property('text', '$'.number_format($amt,2));
    }
    $row_color = ($row_num%2==1) ? '#dddddd' : '#ffffff';
    $cell->set_property('cell-background', $row_color);
}

// process user selection
function on_selection($selection) {
    list($model, $iter) = $selection->get_selected();
    if ($iter==null) return;
    $desc = $model->get_value($iter, 1);
    $qty = $model->get_value($iter, 2);
    $price = $model->get_value($iter, 3);
    echo "You have selected $desc: $qty ($price)\n";
}

?>

Output

As shown above.

 

Explanation

The above example is based on How to display tooltips in GtkTreeView - Part 1?.

What's new here:

  1. The $event->y given by function on_enter($view, $event) has its 0 at the top of the first row, whereas GtkWidget::get_pointer() starts its 0 at the top of the scroll window (i.e. the top of the column header). This difference allows us to detect if the mouse is in the header region.
  2. Note that 25 is the standard height of the column header. Yes, this is a hardcode. The value might be different on your system if you use a different font. If you don't like the hardcode, you might want to refer to How to display tooltips in GtkTreeView - Part 3 - no hardcoding of header height?
  3. This line fixes the bug as pointed out by Stefan Vasilev in the comments below.

Related Links

Add comment


Security code
Refresh