subtitle: thread safe. async load in qml

ninecents · Sep 8, 2014 · 8b66627 · 8b66627
1 parent 656ed20
commit 8b66627
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Showing 3 changed files with 38 additions and 7 deletions.
diff --git a/qml/QuickSubtitle.cpp b/qml/QuickSubtitle.cpp
@@ -46,7 +46,7 @@ void QuickSubtitle::onPlayerSourceChanged()
     path = QFileInfo(path).dir().absoluteFilePath(name);
     qDebug() << "open subtitle:" << path;
     setFileName(path);
-    load();
+    loadAsync();
 }
 
 void QuickSubtitle::onPlayerPositionChanged()

diff --git a/src/QtAV/Subtitle.h b/src/QtAV/Subtitle.h
@@ -124,6 +124,7 @@ public slots:
      * start to process the whole subtitle content in a thread
      */
     void load();
+    void loadAsync();
     void setTimestamp(qreal t);
 signals:
     void codecChanged();

diff --git a/src/Subtitle.cpp b/src/Subtitle.cpp
@@ -31,8 +31,10 @@
 #include <QtCore/QLinkedList>
 #include <QtCore/QRegExp>
 #include <QtCore/QRunnable>
+#include <QtCore/QThreadPool>
 #include <QtCore/QTextCodec>
 #include <QtCore/QTextStream>
+#include <QtCore/QMutexLocker>
 
 namespace QtAV {
 
@@ -48,6 +50,9 @@ class Subtitle::Private {
         , t(0)
     {}
     void reset() {
+        QMutexLocker lock(&mutex);
+        Q_UNUSED(lock);
+        loaded = false;
         processor = 0;
         update_image = true;
         t = 0;
@@ -93,6 +98,7 @@ class Subtitle::Private {
     qreal t;
     SubtitleFrame frame;
     QLinkedList<SubtitleFrame>::iterator itf;
+    QMutex mutex;
 };
 
 Subtitle::Subtitle(QObject *parent) :
@@ -239,12 +245,16 @@ QStringList Subtitle::suffixes() const
 
 void Subtitle::setTimestamp(qreal t)
 {
-    priv->t = t;
-    if (!isLoaded())
-        return;
-    if (!priv->prepareCurrentFrame())
-        return;
-    priv->update_image = true;
+    {
+        QMutexLocker lock(&priv->mutex);
+        Q_UNUSED(lock);
+        priv->t = t;
+        if (!isLoaded())
+            return;
+        if (!priv->prepareCurrentFrame())
+            return;
+        priv->update_image = true;
+    }
     emit contentChanged();
 }
 
@@ -257,6 +267,7 @@ void Subtitle::load()
 {
     priv->reset();
     emit contentChanged(); //notify user to update subtitle
+    // lock is not needed because it's not loaded now
     if (!priv->url.isEmpty()) {
         // need qt network module network
         return;
@@ -293,15 +304,34 @@ void Subtitle::load()
     }
 }
 
+void Subtitle::loadAsync()
+{
+    class Loader : public QRunnable {
+    public:
+        Loader(Subtitle *sub) : m_sub(sub) {}
+        void run() {
+            if (m_sub)
+                m_sub->load();
+        }
+    private:
+        Subtitle *m_sub;
+    };
+    QThreadPool::globalInstance()->start(new Loader(this));
+}
+
 QString Subtitle::getText() const
 {
+    QMutexLocker lock(&priv->mutex);
+    Q_UNUSED(lock);
     if (!isLoaded())
         return QString();
     return priv->frame.text;
 }
 
 QImage Subtitle::getImage(int width, int height)
 {
+    QMutexLocker lock(&priv->mutex);
+    Q_UNUSED(lock);
     if (!isLoaded())
         return QImage();
     if (!priv->frame || width == 0 || height == 0)