[gnome-shell/wip/fmuellner/calendar-refresh: 12/12] mpris: Make forward/backward insensitive when unavailable

[Florian MĂźllner <fmuellner src gnome org>]

commit 0ed2244d1a046c44c20c66dc263cb37aac461a7b
Author: Florian MĂźllner <fmuellner gnome org>
Date:   Thu Nov 3 18:11:54 2016 +0100

    mpris: Make forward/backward insensitive when unavailable
    
    Media notifications currently always show the forward and backward
    buttons as clickable, regardless of whether the corresponding action
    is available or not. Media players usually address this by rendering
    controls insensitive in this case, so do the same here.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=773884

 data/theme/gnome-shell-high-contrast.css |    2 ++
 data/theme/gnome-shell.css               |    2 ++
 js/ui/mpris.js                           |   21 +++++++++++++++++++--
 3 files changed, 23 insertions(+), 2 deletions(-)
---
diff --git a/data/theme/gnome-shell-high-contrast.css b/data/theme/gnome-shell-high-contrast.css
index 6a3f875..b46a695 100644
--- a/data/theme/gnome-shell-high-contrast.css
+++ b/data/theme/gnome-shell-high-contrast.css
@@ -912,6 +912,8 @@ StScrollBar {
     padding-right: 18px; }
   .message-media-control:last-child:rtl {
     padding-left: 18px; }
+  .message-media-control:insensitive {
+    color: #999999; }
 
 .media-message-cover-icon {
   icon-size: 48px !important; }
diff --git a/data/theme/gnome-shell.css b/data/theme/gnome-shell.css
index 58a7656..5f2d39f 100644
--- a/data/theme/gnome-shell.css
+++ b/data/theme/gnome-shell.css
@@ -912,6 +912,8 @@ StScrollBar {
     padding-right: 18px; }
   .message-media-control:last-child:rtl {
     padding-left: 18px; }
+  .message-media-control:insensitive {
+    color: #8e8e80; }
 
 .media-message-cover-icon {
   icon-size: 48px !important; }
diff --git a/js/ui/mpris.js b/js/ui/mpris.js
index b42d9aa..a5ca66f 100644
--- a/js/ui/mpris.js
+++ b/js/ui/mpris.js
@@ -36,6 +36,8 @@ const MprisPlayerIface = '<node> \
   <method name="PlayPause" /> \
   <method name="Next" /> \
   <method name="Previous" /> \
+  <property name="CanGoNext" type="b" access="read" /> \
+  <property name="CanGoPrevious" type="b" access="read" /> \
   <property name="CanPlay" type="b" access="read" /> \
   <property name="Metadata" type="a{sv}" access="read" /> \
   <property name="PlaybackStatus" type="s" access="read" /> \
@@ -57,7 +59,7 @@ const MediaMessage = new Lang.Class({
         this._icon = new St.Icon({ style_class: 'media-message-cover-icon' });
         this.setIcon(this._icon);
 
-        this.addMediaControl('media-skip-backward-symbolic',
+        this._prevButton = this.addMediaControl('media-skip-backward-symbolic',
             Lang.bind(this, function() {
                 this._player.previous();
             }));
@@ -67,7 +69,7 @@ const MediaMessage = new Lang.Class({
                 this._player.playPause();
             }));
 
-        this.addMediaControl('media-skip-forward-symbolic',
+        this._nextButton = this.addMediaControl('media-skip-forward-symbolic',
             Lang.bind(this, function() {
                 this._player.next();
             }));
@@ -82,6 +84,10 @@ const MediaMessage = new Lang.Class({
         Main.panel.closeCalendar();
     },
 
+    _updateNavButton: function(button, sensitive) {
+        button.reactive = sensitive;
+    },
+
     _update: function() {
         this.setTitle(this._player.trackArtists.join(', '));
         this.setBody(this._player.trackTitle);
@@ -99,6 +105,9 @@ const MediaMessage = new Lang.Class({
         let iconName = isPlaying ? 'media-playback-pause-symbolic'
                                  : 'media-playback-start-symbolic';
         this._playPauseButton.child.icon_name = iconName;
+
+        this._updateNavButton(this._prevButton, this._player.canGoPrevious);
+        this._updateNavButton(this._nextButton, this._player.canGoNext);
     }
 });
 
@@ -139,10 +148,18 @@ const MprisPlayer = new Lang.Class({
         this._playerProxy.PlayPauseRemote();
     },
 
+    get canGoNext() {
+        return this._playerProxy.CanGoNext;
+    },
+
     next: function() {
         this._playerProxy.NextRemote();
     },
 
+    get canGoPrevious() {
+        return this._playerProxy.CanGoPrevious;
+    },
+
     previous: function() {
         this._playerProxy.PreviousRemote();
     },