mpris: Make forward/backward insensitive when unavailablewip/fmuellner/calendar-refresh

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

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 6a3f87594..b46a695c8 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 58a76566d..5f2d39ff4 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 b42d9aa57..a5ca66f4d 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();
     },