service/mpris: make lengthSupported bindable and notify for changes

Fixes #109

Author: outfoxxed

src/services/mpris/player.cpp

@@ -99,6 +99,8 @@ MprisPlayer::MprisPlayer(const QString& address, QObject* parent): QObject(paren
 		} else return static_cast<qlonglong>(-1);
 	});
 
+	this->bLengthSupported.setBinding([this]() { return this->bInternalLength != -1; });
+
 	this->bPlaybackState.setBinding([this]() {
 		const auto& status = this->bpPlaybackStatus.value();
 
@@ -258,21 +260,19 @@ void MprisPlayer::setPosition(qlonglong position) {
 }
 
 void MprisPlayer::onExportedPositionChanged() {
-	if (!this->lengthSupported()) emit this->lengthChanged();
+	if (!this->bLengthSupported) emit this->lengthChanged();
 }
 
 void MprisPlayer::onSeek(qlonglong time) { this->setPosition(time); }
 
 qreal MprisPlayer::length() const {
-	if (this->bInternalLength == -1) {
+	if (!this->bLengthSupported) {
 		return this->position(); // unsupported
 	} else {
 		return static_cast<qreal>(this->bInternalLength / 1000) / 1000; // NOLINT
 	}
 }
 
-bool MprisPlayer::lengthSupported() const { return this->bInternalLength != -1; }
-
 bool MprisPlayer::volumeSupported() const { return this->pVolume.exists(); }
 
 void MprisPlayer::setVolume(qreal volume) {

src/services/mpris/player.hpp

@@ -117,7 +117,7 @@ class MprisPlayer: public QObject {
 	/// The length of the playing track, as seconds, with millisecond precision,
 	/// or the value of @@position if @@lengthSupported is false.
 	Q_PROPERTY(qreal length READ length NOTIFY lengthChanged);
-	Q_PROPERTY(bool lengthSupported READ lengthSupported NOTIFY lengthSupportedChanged);
+	Q_PROPERTY(bool lengthSupported READ default NOTIFY lengthSupportedChanged BINDABLE bindableLengthSupported);
 	/// The volume of the playing track from 0.0 to 1.0, or 1.0 if @@volumeSupported is false.
 	///
 	/// May only be written to if @@canControl and @@volumeSupported are true.
@@ -274,7 +274,7 @@ class MprisPlayer: public QObject {
 	void setPosition(qreal position);
 
 	[[nodiscard]] qreal length() const;
-	[[nodiscard]] bool lengthSupported() const;
+	[[nodiscard]] QBindable<bool> bindableLengthSupported() const { return &this->bLengthSupported; }
 
 	[[nodiscard]] qreal volume() const { return this->bVolume; };
 	[[nodiscard]] bool volumeSupported() const;
@@ -447,6 +447,7 @@ private slots:
 	Q_OBJECT_BINDABLE_PROPERTY(MprisPlayer, QString, bTrackAlbumArtist, &MprisPlayer::trackAlbumArtistChanged);
 	Q_OBJECT_BINDABLE_PROPERTY(MprisPlayer, QString, bTrackArtUrl, &MprisPlayer::trackArtUrlChanged);
 	Q_OBJECT_BINDABLE_PROPERTY(MprisPlayer, qlonglong, bInternalLength, &MprisPlayer::lengthChanged);
+	Q_OBJECT_BINDABLE_PROPERTY(MprisPlayer, bool, bLengthSupported, &MprisPlayer::lengthSupportedChanged);
 	Q_OBJECT_BINDABLE_PROPERTY(MprisPlayer, bool, bShuffle, &MprisPlayer::shuffleChanged);
 
 	QS_DBUS_BINDABLE_PROPERTY_GROUP(MprisPlayer, playerProperties);