diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/html/training/camera/cameradirect.jd | 51 | ||||
| -rw-r--r-- | docs/html/training/camera/index.jd | 2 |
2 files changed, 16 insertions, 37 deletions
diff --git a/docs/html/training/camera/cameradirect.jd b/docs/html/training/camera/cameradirect.jd index d37f2c4..1e25d4f 100644 --- a/docs/html/training/camera/cameradirect.jd +++ b/docs/html/training/camera/cameradirect.jd @@ -45,29 +45,11 @@ or something fully integrated in your app UI, this lesson shows you how.</p> process of directly controlling the camera. As Android's own Camera application does, the recommended way to access the camera is to open {@link android.hardware.Camera} on a separate thread that's launched from {@link android.app.Activity#onCreate onCreate()}. This approach is a good idea -since it can take a while and might bog down the UI thread. However, in the sample application -associated with this lesson, opening the camera is deferred to the {@link +since it can take a while and might bog down the UI thread. In a more basic implementation, +opening the camera can be deferred to the {@link android.app.Activity#onResume onResume()} method to facilitate code reuse and keep the flow of control simple.</p> -<pre> -private void openCameraPerIdAndSetPreview() { - if (! safeCameraOpen(mCameraId)) { - mCameraId = getFirstRearCameraID(); - safeCameraOpen(mCameraId); - } - - mPreview.setCamera(mCamera); -} -</pre> - -<p>Since API level 9, the camera framework supports multiple cameras. If you use the -legacy API and call {@link android.hardware.Camera#open open()} without an -argument, you get the first rear-facing camera. Dealing with multiple cameras -is an advanced topic and beyond the scope of this lesson. If you are really -interested, check out the implementation of {@code getFirstRearCameraID()} in -the sample app (downloadable at the top).</p> - <p>Calling {@link android.hardware.Camera#open Camera.open()} throws an exception if the camera is already in use by another application, so we wrap it in a {@code try} block.</p> @@ -78,7 +60,7 @@ private boolean safeCameraOpen(int id) { try { releaseCameraAndPreview(); - mCamera = Camera.open(mCameraId); + mCamera = Camera.open(id); qOpened = (mCamera != null); } catch (Exception e) { Log.e(getString(R.string.app_name), "failed to open Camera"); @@ -97,6 +79,10 @@ private void releaseCameraAndPreview() { } </pre> +<p>Since API level 9, the camera framework supports multiple cameras. If you use the +legacy API and call {@link android.hardware.Camera#open open()} without an +argument, you get the first rear-facing camera.</p> + <h2 id="camera-preview">Create the Camera Preview</h2> @@ -113,13 +99,10 @@ data from the camera hardware the application.</p> <pre> class Preview extends ViewGroup implements SurfaceHolder.Callback { -... SurfaceView mSurfaceView; SurfaceHolder mHolder; -... - Preview(Context context) { super(context); @@ -137,14 +120,13 @@ class Preview extends ViewGroup implements SurfaceHolder.Callback { </pre> <p>The preview class must be passed to the {@link android.hardware.Camera} object before the live -image preview can be started, as seen in {@code setCamera()} method of the sample, -as shown in the next section.</p> +image preview can be started, as shown in the next section.</p> <h3 id="TaskStartPreview">Set and Start the Preview</h2> <p>A camera instance and its related preview must be created in a specific -order, with the camera object being first. In the sample application, the +order, with the camera object being first. In the snippet below, the process of initializing the camera is encapsulated so that {@link android.hardware.Camera#startPreview Camera.startPreview()} is called by the {@code setCamera()} method, whenever the user does something to change the @@ -183,9 +165,8 @@ public void setCamera(Camera camera) { <h2 id="TaskSettings">Modify Camera Settings</h2> <p>Camera settings change the way that the camera takes pictures, from the zoom -level to exposure compensation. This example doesn’t do a whole lot with camera -settings, but the APIs provide a wide array of options. The {@code surfaceChanged()} method in the -sample app demonstrates how to get and set camera parameters:</p> +level to exposure compensation. This example changes only the preview size; +see the source code of the Camera application for many more.</p> <pre> public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { @@ -221,9 +202,7 @@ to API level 14, you must stop your preview before changing the orientation and method to take a picture once the preview is started. You can create {@link android.hardware.Camera.PictureCallback} and {@link android.hardware.Camera.ShutterCallback} objects and pass them into {@link -android.hardware.Camera#takePicture Camera.takePicture()}. Since the Android -Camera application already does a great job capturing JPEG images, you should -probably implement the raw-image callback.</p> +android.hardware.Camera#takePicture Camera.takePicture()}.</p> <p>If you want to grab images continously, you can create a {@link android.hardware.Camera.PreviewCallback} that implements {@link @@ -236,8 +215,8 @@ takePicture()}.</p> <h2 id="TaskRestartPreview">Restart the Preview</h2> <p>After a picture is taken, you must to restart the preview before the user -can take another picture. In the example, the restart is done by overloading -the shutter button, as shown below.</p> +can take another picture. In this example, the restart is done by overloading +the shutter button.</p> <pre> @Override @@ -302,7 +281,7 @@ private void stopPreviewAndFreeCamera() { } </pre> -<p>In the example application, this procedure is also part of the {@code +<p>Earlier in the lesson, this procedure was also part of the {@code setCamera()} method, so initializing a camera always begins with stopping the preview.</p> diff --git a/docs/html/training/camera/index.jd b/docs/html/training/camera/index.jd index 400f636..31adfe8 100644 --- a/docs/html/training/camera/index.jd +++ b/docs/html/training/camera/index.jd @@ -28,7 +28,7 @@ next.link=photobasics.html <h2>Try it out</h2> <div class="download-box"> - <a href="{@docRoot}shareables/training/PhotoIntentActivity.zip" class="button">Download the Intent sample</a> + <a href="{@docRoot}shareables/training/PhotoIntentActivity.zip" class="button">Download the sample</a> <p class="filename">PhotoIntentActivity.zip</p> </div> |