So I have a dialogue where I want to show the front and back camera previews sequentially, say after 2 seconds delay. Problem is, I can always set 1 camera view to the frame, how to I change it on the fly, automatically?
Here is where I want to change it on the fly:
public class CameraExample extends AnimatedViewContainer {
private final static String TAG = "CameraExample";
private Camera mCamera;
private CameraPreview mPreview;
private Context mContext;
public CameraExample(Context context, int i) {
super(context, i);
mPreview = null;
mContext = context;
initCamera(mContext);
}
// A safe way to get an instance of the Camera object.
public static Camera getCameraInstance(int cameraId) {
Camera c = null;
try {
// attempt to get a Camera instance
c = Camera.open(cameraId);
} catch (Exception e) {
// Camera is not available (in use or does not exist)
Log.e(TAG, "CameraExample: " + "camera not available (in use or does not exist); " + e.getMessage());
}
return c; // returns null if camera is unavailable
}
private void initCamera(Context context) {
// Check if this device has a camera
if (!context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
// no camera on this device
Log.e(TAG, "CameraExample: " + "this device has no camera");
} else {
// this device has a camera
int numCameras = Camera.getNumberOfCameras();
if (numCameras >= 0) {
for (int cameraId = 0; cameraId < numCameras; cameraId++) {
mCamera = getCameraInstance(cameraId);
if (mCamera != null) {
CameraInfo cameraInfo = new CameraInfo();
Camera.getCameraInfo(cameraId, cameraInfo);
if (cameraInfo.facing == CameraInfo.CAMERA_FACING_FRONT) {
try {
//Create our Preview view and set it as the content of this LinearLayout View
mPreview = new CameraPreview(context, mCamera, cameraId);
} catch (RuntimeException e) {
Log.e(TAG, "Camera failed to open: " + e.getLocalizedMessage());
}
}
if (createView() == false) {
break;
}
}
}
}
}
}
@Override
public void onCreateViewContent(LayoutInflater layoutInflater, ViewGroup parentGroup, View[] containerViews, int index) {
containerViews[index] = layoutInflater.inflate(R.layout.example_camera, parentGroup, false);
FrameLayout previewFrame = (FrameLayout) containerViews[index].findViewById(R.id.preview);
// Add preview for inflation
previewFrame.addView(mPreview);
}
@Override
public void cleanup() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}
}
The CameraPreview class:
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private static final String TAG = "CameraPreview";
private Context mContext;
private SurfaceHolder mHolder;
private Camera mCamera;
private int mCameraId;
public CameraPreview(Context context, Camera camera, int cameraId) {
super(context);
mContext = context;
mCamera = camera;
mCameraId = cameraId;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
Log.e(TAG, "CameraExample: " + "Error setting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null) {
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e) {
// ignore: tried to stop a non-existent preview
}
}
}
I set my view here:
@Override
public void onCreateViewContent(LayoutInflater layoutInflater, ViewGroup parentGroup, View[] containerViews, int index) {
containerViews[index] = layoutInflater.inflate(R.layout.example_camera, parentGroup, false);
FrameLayout previewFrame = (FrameLayout) containerViews[index].findViewById(R.id.preview);
previewFrame.addView(mPreview);
}
Problem is, I don't see how I can have 2 instances of the 2 different cameras that a device generally has and change them automatically after certain seconds so that my frame displays the front and back camera preview one after other after every certain amount of seconds. Any solution is highly appreciated! I think I have to handle it in the surfaceChanged() method, but I really don't know how!
As asked, here is the, AnimatedViewContainer class:
public abstract class AnimatedViewContainer extends Example {
Context mContext;
int mAnimationDuration;
int mAnimationDurationShort;
LayoutInflater mLayoutInflater;
ViewGroup mParentGroup;
View[] mContainerViews;
boolean hasBeenClicked = false;
int mCurrentIndex;
int mMaxNumItems;
int mIndexVisibleItem;
public AnimatedViewContainer(Context context, int maxNumItems) {
super(context);
mContext = context;
mMaxNumItems = maxNumItems;
mContainerViews = new View[mMaxNumItems];
// Retrieve and cache the system's default "medium" animation time
mAnimationDuration = getResources().getInteger(android.R.integer.config_mediumAnimTime);
// and "short"
mAnimationDurationShort = getResources().getInteger(android.R.integer.config_shortAnimTime);
mCurrentIndex = 0;
mLayoutInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//TODO: shouldn't be null, should be any ViewGroup with the right LayoutParams
mParentGroup = null;
}
public abstract void onCreateViewContent(LayoutInflater layoutInflater, ViewGroup parentGroup, View[] containerViews, int index);
public boolean createView() {
if (mCurrentIndex >= mMaxNumItems) {
return false; // indicates to terminate the loop
}
// handle/execute the concrete definition of the view content defined by the child class
onCreateViewContent(mLayoutInflater, mParentGroup, mContainerViews, mCurrentIndex);
// only the first container view should be visible
if (mCurrentIndex == 0) {
mContainerViews[mCurrentIndex].setVisibility(View.VISIBLE);
mIndexVisibleItem = mCurrentIndex;
} else {
mContainerViews[mCurrentIndex].setVisibility(View.GONE);
}
// if you click on the container view, show next container view with a crossfade animation
mContainerViews[mCurrentIndex].setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
crossfade(true);
hasBeenClicked = true;
}
});
// add the container view to the FrameLayout
addView(mContainerViews[mCurrentIndex]);
mCurrentIndex++;
return true;
}
public void crossfade(boolean manuallyClicked) {
//only rotate when example is actually shown and at least one content item was created. This may also prevent NPEs due to incompletely loaded views.
if(!this.isShown() || mCurrentIndex == 0)
return;
//when example was previously clicked, don't do anything
if(!manuallyClicked && hasBeenClicked){
hasBeenClicked = false;
return;
}
int numTotalItems = mCurrentIndex;
final int indexVisibleItem = mIndexVisibleItem;
int nextIndex = indexVisibleItem + 1;
if (nextIndex >= numTotalItems) {
nextIndex = 0;
}
final boolean hasOnlyOneItem;
if (numTotalItems == 1) {
hasOnlyOneItem = true;
} else {
hasOnlyOneItem = false;
}
if (hasOnlyOneItem) { //there is only one item in the mContainerViews
mContainerViews[indexVisibleItem].animate().alpha(0.5f).setDuration(mAnimationDurationShort).setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
mContainerViews[indexVisibleItem].animate().alpha(1f).setDuration(mAnimationDurationShort).setListener(null);
}
});
} else {
// Set the next view to 0% opacity but visible, so that it is visible (but fully transparent) during the animation.
mContainerViews[nextIndex].setAlpha(0f);
mContainerViews[nextIndex].setVisibility(View.VISIBLE);
// Animate the next view to 100% opacity, and clear any animation
// listener set on the view.
mContainerViews[nextIndex].animate().alpha(1f).setDuration(mAnimationDuration).setListener(null);
// Animate the current view to 0% opacity. After the animation ends,
// set its visibility to GONE as an optimization step (it won't participate in layout passes, etc.)
mContainerViews[indexVisibleItem].animate().alpha(0f).setDuration(mAnimationDuration).setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
mContainerViews[indexVisibleItem].setVisibility(View.GONE);
}
});
}
mIndexVisibleItem = nextIndex;
}
@Override
public void cleanup() {
}
}
