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tutorials: ios: basic: fix missing markup

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Reynaldo H. Verdejo Pinochet 2017-10-19 14:33:33 -07:00
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markdown/tutorials/ios/a-basic-media-player.md
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@ -5,8 +5,8 @@
![screenshot] ![screenshot]
Enough testing with synthetic images and audio tones! This tutorial Enough testing with synthetic images and audio tones! This tutorial
finally plays actual media, streamed directly from the Internet, in your finally shows how to play actual media in your iOS device; media streamed
iOS device. It shows: directly from the Internet!. We will review:
- How to keep the User Interface regularly updated with the current - How to keep the User Interface regularly updated with the current
playback position and duration playback position and duration
@ -91,7 +91,7 @@ Also note that the class has been renamed from `ViewController` to
## The Video View Controller ## The Video View Controller
The `ViewController `class manages the UI, instantiates The `ViewController` class manages the UI, instantiates
the `GStreamerBackend` and also performs some UI-related tasks on its the `GStreamerBackend` and also performs some UI-related tasks on its
behalf: behalf:
@ -390,7 +390,7 @@ To the left of the Seek Bar (refer to the screenshot at the top of this
page), there is page), there is
a [TextField](https://developer.apple.com/library/ios/#documentation/UIKit/Reference/UITextField_Class/Reference/UITextField.html) widget a [TextField](https://developer.apple.com/library/ios/#documentation/UIKit/Reference/UITextField_Class/Reference/UITextField.html) widget
which we will use to display the current position and duration in which we will use to display the current position and duration in
"`HH:mm:ss / HH:mm:ss"` textual format. The `updateTimeWidget` method "`HH:mm:ss / HH:mm:ss`" textual format. The `updateTimeWidget` method
takes care of it, and must be called every time the Seek Bar is takes care of it, and must be called every time the Seek Bar is
updated: updated:
@ -446,8 +446,7 @@ the Slider.
`sliderTouchDown` is called when the user starts dragging. Here we pause `sliderTouchDown` is called when the user starts dragging. Here we pause
the pipeline because if the user is searching for a particular scene, we the pipeline because if the user is searching for a particular scene, we
do not want it to keep moving. We also mark that a drag operation is in do not want it to keep moving. We also mark that a drag operation is in
progress in the progress in the `dragging_slider` variable.
`dragging_slider` variable.
``` ```
/* Called when the time slider position has changed, either because the user dragged it or /* Called when the time slider position has changed, either because the user dragged it or
@ -910,16 +909,15 @@ one):
We first need to obtain a plain `char *` from within the `NSString *` we We first need to obtain a plain `char *` from within the `NSString *` we
get, using the `UTF8String` method. get, using the `UTF8String` method.
`playbin`’s URI is exposed as a common GObject property, so we simply `playbin`’s URI is exposed as a common `GObject` property, so we simply
set it with `g_object_set()`. set it with `g_object_set()`.
### Reporting media size ### Reporting media size
Some codecs allow the media size (width and height of the video) to Some codecs allow the media size (width and height of the video) to
change during playback. For simplicity, this tutorial assumes that they change during playback. For simplicity, this tutorial assumes that they
do not. Therefore, in the READY to PAUSED state change, once the Caps of do not. Therefore, in the `READY` to `PAUSED` state change, once the Caps of
the decoded media are known, we inspect them the decoded media are known, we inspect them in `check_media_size()`:
in `check_media_size()`:
``` ```
/* Retrieve the video sink's Caps and tell the application about the media size */ /* Retrieve the video sink's Caps and tell the application about the media size */
@ -978,8 +976,7 @@ right before entering the main loop:
g_source_unref (timeout_source); g_source_unref (timeout_source);
``` ```
Then, in the refresh\_ui Then, in the refresh_ui method:
method:
``` ```
/* If we have pipeline and it is running, query the current position and clip duration and inform /* If we have pipeline and it is running, query the current position and clip duration and inform
@ -1021,7 +1018,7 @@ need to honor the calls to `setPosition` and instruct the pipeline to
jump to the indicated position. jump to the indicated position.
There are, though, a couple of caveats. Firstly, seeks are only possible There are, though, a couple of caveats. Firstly, seeks are only possible
when the pipeline is in the PAUSED or PLAYING state, and we might when the pipeline is in the `PAUSED` or `PLAYING` state, and we might
receive seek requests before that happens. Secondly, dragging the Seek receive seek requests before that happens. Secondly, dragging the Seek
Bar can generate a very high number of seek requests in a short period Bar can generate a very high number of seek requests in a short period
of time, which is visually useless and will impair responsiveness. Let’s of time, which is visually useless and will impair responsiveness. Let’s
@ -1060,7 +1057,7 @@ the `state_changed_cb()` callback:
} }
``` ```
Once the pipeline moves from the READY to the PAUSED state, we check if Once the pipeline moves from the `READY` to the `PAUSED` state, we check if
there is a pending seek operation and execute it. there is a pending seek operation and execute it.
The `desired_position` variable is reset inside `execute_seek()`. The `desired_position` variable is reset inside `execute_seek()`.
@ -1185,7 +1182,7 @@ static void buffering_cb (GstBus *bus, GstMessage *msg, GStreamerBackend *self)
`target_state` is the state in which we have been instructed to set the `target_state` is the state in which we have been instructed to set the
pipeline, which might be different to the current state, because pipeline, which might be different to the current state, because
buffering forces us to go to PAUSED. Once buffering is complete we set buffering forces us to go to `PAUSED`. Once buffering is complete we set
the pipeline to the `target_state`. the pipeline to the `target_state`.
## Conclusion ## Conclusion
@ -1207,4 +1204,4 @@ The next tutorial adds the missing bits to turn the application built
here into an acceptable iOS media player. here into an acceptable iOS media player.
[information]: images/icons/emoticons/information.png [information]: images/icons/emoticons/information.png
[screenshot]: images/tutorials/ios-a-basic-media-player-screenshot.png [screenshot]: images/tutorials/ios-a-basic-media-player-screenshot.png