Better handling of state tracking in the UI. It now tracks what gst does, instead of just guessing from the buttons the user pressed.

gst-sdk/tutorials/android-tutorial-1/jni/tutorial-1.c

@@ -40,6 +40,7 @@ static JavaVM *java_vm;
 static jfieldID custom_data_field_id;
 static jmethodID set_message_method_id;
 static jmethodID set_current_position_method_id;
+static jmethodID set_current_state_method_id;
 static jmethodID on_gstreamer_initialized_method_id;
 
 /*
@@ -92,7 +93,7 @@ static void set_ui_message (const gchar *message, CustomData *data) {
 
 static void set_current_ui_position (gint position, gint duration, CustomData *data) {
   JNIEnv *env = get_jni_env ();
-  GST_DEBUG ("Setting current position/duration to: %d / %d (ms)", position, duration);
+//  GST_DEBUG ("Setting current position/duration to: %d / %d (ms)", position, duration);
   (*env)->CallVoidMethod (env, data->app, set_current_position_method_id, position, duration);
   if ((*env)->ExceptionCheck (env)) {
     GST_ERROR ("Failed to call Java method");
@@ -151,16 +152,22 @@ static void eos_cb (GstBus *bus, GstMessage *msg, CustomData *data) {
 }
 
 static void state_changed_cb (GstBus *bus, GstMessage *msg, CustomData *data) {
+  JNIEnv *env = get_jni_env ();
   GstState old_state, new_state, pending_state;
   gst_message_parse_state_changed (msg, &old_state, &new_state, &pending_state);
   /* Only pay attention to messages coming from the pipeline, not its children */
   if (GST_MESSAGE_SRC (msg) == GST_OBJECT (data->pipeline)) {
-    set_ui_message (gst_element_state_get_name (new_state), data);
     data->state = new_state;
     if (data->state >= GST_STATE_PAUSED && GST_CLOCK_TIME_IS_VALID (data->desired_position)) {
       execute_seek (data->desired_position, data);
       data->desired_position = GST_CLOCK_TIME_NONE;
     }
+    GST_DEBUG ("State changed to %s, notifying application", gst_element_state_get_name(new_state));
+    (*env)->CallVoidMethod (env, data->app, set_current_state_method_id, new_state);
+    if ((*env)->ExceptionCheck (env)) {
+      GST_ERROR ("Failed to call Java method");
+      (*env)->ExceptionClear (env);
+    }
   }
 }
 
@@ -303,8 +310,11 @@ jboolean gst_class_init (JNIEnv* env, jclass klass) {
   GST_DEBUG ("The MethodID for the setCurrentPosition method is %p", set_current_position_method_id);
   on_gstreamer_initialized_method_id = (*env)->GetMethodID (env, klass, "onGStreamerInitialized", "()V");
   GST_DEBUG ("The MethodID for the onGStreamerInitialized method is %p", on_gstreamer_initialized_method_id);
+  set_current_state_method_id = (*env)->GetMethodID (env, klass, "setCurrentState", "(I)V");
+  GST_DEBUG ("The MethodID for the setCurrentState method is %p", set_current_state_method_id);
 
-  if (!custom_data_field_id || !set_message_method_id || !set_current_position_method_id || ! on_gstreamer_initialized_method_id) {
+  if (!custom_data_field_id || !set_message_method_id || !set_current_position_method_id ||
+      !on_gstreamer_initialized_method_id || !set_current_state_method_id) {
     GST_ERROR ("The calling class does not implement all necessary interface methods");
     return JNI_FALSE;
   }

gst-sdk/tutorials/android-tutorial-1/src/com/gst_sdk_tutorials/tutorial_1/Tutorial1.java

@@ -71,7 +71,6 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         play.setOnClickListener(new OnClickListener() {
             public void onClick(View v) {
                 nativePlay();
-                playing = true;
             }
         });
 
@@ -79,7 +78,6 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         pause.setOnClickListener(new OnClickListener() {
             public void onClick(View v) {
                 nativePause();
-                playing = false;
             }
         });
 
@@ -107,6 +105,7 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         super.onDestroy();
     }
 
+    /* Called from native code */
     private void setMessage(final String message) {
         final TextView tv = (TextView) this.findViewById(R.id.textview_message);
         runOnUiThread (new Runnable() {
@@ -116,17 +115,18 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         });
     }
 
+    /* Called from native code */
     private void onGStreamerInitialized () {
         if (initialization_data != null) {
-            playing = initialization_data.getBoolean("playing");
+            boolean should_play = initialization_data.getBoolean("playing");
             int milliseconds = initialization_data.getInt("position");
-            Log.i ("GStreamer", "Restoring state, playing:" + playing + " position:" + milliseconds + " ms.");
+            Log.i ("GStreamer", "Restoring state, playing:" + should_play + " position:" + milliseconds + " ms.");
             /* Actually, move to one millisecond in the future. Otherwise, due to rounding errors between the
              * milliseconds used here and the nanoseconds used by GStreamer, we would be jumping a bit behind
              * where we were before. This, combined with seeking to keyframe positions, would skip one keyframe
              * backwards on each iteration. */
             nativeSetPosition(milliseconds + 1);
-            if (playing) {
+            if (should_play) {
                 nativePlay();
             } else {
                 nativePause();
@@ -136,6 +136,7 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         }
     }
 
+    /* Called from native code */
     private void setCurrentPosition(final int position, final int duration) {
         final TextView tv = (TextView) this.findViewById(R.id.textview_time);
         final SeekBar sb = (SeekBar) this.findViewById(R.id.seek_bar);
@@ -153,6 +154,26 @@ public class Tutorial1 extends Activity implements SurfaceHolder.Callback, OnSee
         this.duration = duration;
     }
 
+    /* Called from native code */
+    private void setCurrentState (int state) {
+        Log.d ("GStreamer", "State has changed to " + state);
+        switch (state) {
+        case 1:
+            setMessage ("NULL");
+            break;
+        case 2:
+            setMessage ("READY");
+            break;
+        case 3:
+            setMessage ("PAUSED");
+            break;
+        case 4:
+            setMessage ("PLAYING");
+            break;
+        }
+        playing = (state == 4);
+    }
+
     static {
         System.loadLibrary("gstreamer_android");
         System.loadLibrary("tutorial-1");