453. How to drag and drop between two thumbnail images using GtkIconView - Part 3 - both directions with insert?

Problem

Suppose you have displayed two lists of thumbnail images using GtkIconView, and you would like to allow users to drag and drop images between the two views.

In this Part 3, we will allow drag and drop between the two views in both directions (i.e. left to right and right to left) as shown below:

How to drag and drop between two thumbnail images using GtkIconView - Part 3 - both directions with insert?


Solution

Use the technique as outlined in the article Part 2, and just do the same for the other direction.

Important Note: This only works for PHP-GTK2 compliled with gtk+ v2.10 and above. If you are using an older version, for linux, you may follow the step-by-step instructions to recompile php-gtk2 with gtk+ v2.10. For windows, please refer to How to install php gtk2 on windows? You may also want to take a look here to see some of the new exciting PHP-GTK2 Functionalities.


Sample Code

The following image files are required by the sample code below. Please save a copy of the image files and put them in the same directory where you store the sample code.

 square_red.jpg
 square_yellow.jpg
 square_green.jpg
 square_blue.jpg
 square_blue2.jpg
 square_blue3.jpg
 ball_red.png
 ball_yellow.png
 ball_blue3.png
 ball_blue3a.png
 ball_green3.png
 ball_green4.png

1   
2   
3   
4   
7   
8   
9   
10   
11   
12   
13   
14   
15   
16   
17   
18   
19   
22   
23   
26   
27   
28   
29   
30   
31   
34   
35   
36   
37   
38   
39   
40   
41   
42   
43   
44   
45   
46   
47   
48   
49   
50   
51   
52   
53   
54   
55   
56   
57   
58   
59   
60   
61   
65   
68   
69   
70   
71   
72   
74   
75   
76   
78   
79   
80   
81   
83   
84   
85   
86   
87   
88   
89   
90   
91   
92   
93   
94   
95   
96   
97   
98   
99   
101   
103   
104   
105   
106   
107   
108   
109   
110   
111   
114   
115   
116   
117   
119   
121   
122   
123   
126   
127   
128   
129   
130   
132   
133   
134   
135   
136   
137   
138   
139   
140   
141   
143   
144   
145   
146   
148   
150   
151   
153   
154   
156   
157   
158   
160   
161   
162   
<?php
$window = new GtkWindow();
$window->set_title($argv[0]);
$window->set_size_request(600, 400);
$window->connect_simple('destroy', array('Gtk','main_quit'));
$window->add($vbox = new GtkVBox());

// display title
$title = new GtkLabel("Drag and drop between two thumbnail images using GtkIconView\n".
"                      Part 3 - both directions (with insert)");
$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 the two views
$hpane = new GtkHPaned();
$vbox->pack_start($hpane);

// the thumbnail image lists
// 0 = left
// 1 = right
$imagelist[0] = array('square_red.jpg', 'square_yellow.jpg', 'square_green.jpg',
    'square_blue.jpg', 'square_blue2.jpg', 'square_blue3.jpg');
$imagelist[1] = array('ball_red.png', 'ball_yellow.png',
    'ball_blue3.png', 'ball_blue3a.png',
    'ball_green3.png', 'ball_green4.png',);

$left_vbox = setup_iconview(0, 'left');
$right_vbox = setup_iconview(1, 'right');

// setup drag and drop for left to right
$view[0]->drag_source_set(Gdk::BUTTON1_MASK, array( array( 'text/plain', 0, 0)), // note 1
    Gdk::ACTION_COPY|Gdk::ACTION_MOVE); 
$view[0]->connect('drag-data-get', 'on_drag'); 

$view[1]->drag_dest_set(Gtk::DEST_DEFAULT_ALL, 
    array( array( 'text/plain', 0, 0)), Gdk::ACTION_COPY|Gdk::ACTION_MOVE); 
$view[1]->connect('drag-data-received', 'on_drop', $view[0]); 

// setup drag and drop for right to left
$view[1]->drag_source_set(Gdk::BUTTON1_MASK, array( array( 'text/plain', 0, 0)), // note 2
    Gdk::ACTION_COPY|Gdk::ACTION_MOVE); 
$view[1]->connect('drag-data-get', 'on_drag'); 

$view[0]->drag_dest_set(Gtk::DEST_DEFAULT_ALL, 
    array( array( 'text/plain', 0, 0)), Gdk::ACTION_COPY|Gdk::ACTION_MOVE); 
$view[0]->connect('drag-data-received', 'on_drop', $view[1]); 

$hpane->add1($left_vbox);
$hpane->add2($right_vbox);
$view[0]->set_size_request(300, -1);

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

function setup_iconview($id, $label) {
    global $imagelist, $model, $modelfilter, $view;
    $model[$id] = new GtkListStore(GdkPixbuf::gtype, Gtk::TYPE_STRING);
    foreach($imagelist[$id] as $img) {
        $pixbuf = GdkPixbuf::new_from_file($img);
        $model[$id]->append(array($pixbuf, $img));
    }

    $view[$id] = new GtkIconView($model[$id]);
    $view[$id]->set_pixbuf_column(0); // col 0 of the model
    $view[$id]->set_text_column(1); // col 1 of the model
    $view[$id]->set_selection_mode(Gtk::SELECTION_MULTIPLE);
    $view[$id]->set_columns(0);
    $view[$id]->set_item_width(120);

    $vbox = new GtkVBox();
    $scrolled_win = new GtkScrolledWindow();
    $scrolled_win->set_policy( Gtk::POLICY_AUTOMATIC,
        Gtk::POLICY_AUTOMATIC);
    $vbox->pack_start($scrolled_win);
    $scrolled_win->add($view[$id]);
    return $vbox;
}

// process drag
function on_drag($widget, $context, $data, $info, $time) {
    $selection = $widget->get_selected_items();
    if (count($selection)==0) return;  // return if there's no selection
    $data->set_text(serialize($selection));
}

// process drop
function on_drop($widget, $context, $x, $y, $data, $info, $time, $src_view) { // note 3
    $drop_info = $widget->get_dest_item_at_pos($x, $y);
    if ($drop_info) {
        list($path, $position) = $drop_info;
        $func = 'insert';
        if ($position == Gtk::TREE_VIEW_DROP_BEFORE ||
        $position == Gtk::TREE_VIEW_DROP_INTO_OR_BEFORE) {
            $pos = $path[0];
        } else {
            $pos = $path[0]+1;
        }
    } else {
        $func = 'append';
    }

    global $imagelist;
    global $modelfilter, $view;
    $dest_model = $widget->get_model();
    $source_model = $src_view->get_model();

    $data = unserialize($data->data);
    foreach($data as $img) {
        $i = $img[0];

        // remove the source image first
        $src_model = $src_view->get_model();
        $iter = $source_model->get_iter($i);
        $img_name = $source_model->get_value($iter, 1);
        $source_model->remove($iter);

        // append the dragged image to the destination
        $pixbuf = GdkPixbuf::new_from_file($img_name);

        if ($func=='append') {
            $dest_model->append(array($pixbuf, $img_name));
        } elseif ($func = 'insert') {
            $dest_model->insert($pos, array($pixbuf, $img_name));
        }
    }
}

?>

Output

As shown above.

 

Explanation

The above sample code is based on Part 2.

What's new here:

  1. Set up drag and drop from left to right.
  2. Set up drag and drop from right to left.
  3. Note how we're able to handle the drag and drop in both directions using just one signal handler.

Related Links

Add comment


Security code
Refresh