[polari/wip/raresv/nick-popover: 145/149] chatView: Add HoverFilterTag

[Rares Visalom <raresvisalom src gnome org>]

commit 76beec275ba7184d1702568f10923a81b64c4bc3
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Jul 27 22:30:17 2016 +0200

    chatView: Add HoverFilterTag
    
    We want to show the newly added UserPopover when clicking a nick in
    the chat log. Currently those nicks use a common tag for general
    styling and a per-nick tag to represent the online status of the
    nick, however we will also want to indicate that the element is
    activatable by highlighting it on hover. To allow this effect while
    keeping the status color in a per-nick tag, add a HoverFilterTag
    class that takes the color from an existing tag and applies an
    opacity effect when hovered.

 src/chatView.js |   65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 65 insertions(+), 0 deletions(-)
---
diff --git a/src/chatView.js b/src/chatView.js
index 074b5b5..e259f75 100644
--- a/src/chatView.js
+++ b/src/chatView.js
@@ -225,6 +225,71 @@ const ButtonTag = new Lang.Class({
     }
 });
 
+const HoverFilterTag = new Lang.Class({
+    Name: 'HoverFilterTag',
+    Extends: ButtonTag,
+    Properties: {
+        'filtered-tag': GObject.ParamSpec.object('filtered-tag',
+                                                 'filtered-tag',
+                                                 'filtered-tag',
+                                                 GObject.ParamFlags.READWRITE |
+                                                 GObject.ParamFlags.CONSTRUCT_ONLY,
+                                                 Gtk.TextTag.$gtype),
+        'hover-opacity': GObject.ParamSpec.double('hover-opacity',
+                                                  'hover-opacity',
+                                                  'hover-opacity',
+                                                  GObject.ParamFlags.READWRITE,
+                                                  0.0, 1.0, 1.0)
+    },
+
+    _init: function(params) {
+        this._filteredTag = null;
+        this._hoverOpacity = 1.;
+
+        this.parent(params);
+
+        this.connect('notify::hover', () => { this._updateColor(); });
+    },
+
+    _updateColor: function() {
+        if (!this._filteredTag)
+            return;
+
+        let color = this._filteredTag.foreground_rgba;
+        if (this.hover)
+            color.alpha *= this._hoverOpacity;
+        this.foreground_rgba = color;
+    },
+
+    set filtered_tag(value) {
+        this._filteredTag = value;
+        this.notify('filtered-tag');
+
+        this._filteredTag.connect('notify::foreground-rgba', () => {
+            this._updateColor();
+        });
+        this._updateColor();
+    },
+
+    get filtered_tag() {
+        return this._filteredTag;
+    },
+
+    set hover_opacity(value) {
+        if (this._hoverOpacity == value)
+            return;
+        this._hoverOpacity = value;
+        this.notify('hover-opacity');
+
+        if (this.hover)
+            this._updateColor();
+    },
+
+    get hover_opacity() {
+        return this._hoverOpacity;
+    }
+});
+
 const ChatView = new Lang.Class({
     Name: 'ChatView',
     Extends: Gtk.ScrolledWindow,