Add CameraActivity utility class to automate Camera permission request handling

modules/java/generator/android/java/org/opencv/android/CameraActivity.java

+package org.opencv.android;
+
+import android.annotation.TargetApi;
+import android.app.Activity;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.os.Build;
+import android.util.AttributeSet;
+import android.view.View;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static android.Manifest.permission.CAMERA;
+
+public class CameraActivity extends Activity {
+
+    private static final int CAMERA_PERMISSION_REQUEST_CODE = 200;
+
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return new ArrayList<CameraBridgeViewBase>();
+    }
+
+    protected void onCameraPermissionGranted() {
+        List<? extends CameraBridgeViewBase> cameraViews = getCameraViewList();
+        if (cameraViews == null) {
+            return;
+        }
+        for (CameraBridgeViewBase cameraBridgeViewBase: cameraViews) {
+            if (cameraBridgeViewBase != null) {
+                cameraBridgeViewBase.setCameraPermissionGranted();
+            }
+        }
+    }
+
+    @Override
+    protected void onStart() {
+        super.onStart();
+        boolean havePermission = true;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+            if (checkSelfPermission(CAMERA) != PackageManager.PERMISSION_GRANTED) {
+                requestPermissions(new String[]{CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
+                havePermission = false;
+            }
+        }
+        if (havePermission) {
+            onCameraPermissionGranted();
+        }
+    }
+
+    @Override
+    @TargetApi(Build.VERSION_CODES.M)
+    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
+        if (requestCode == CAMERA_PERMISSION_REQUEST_CODE && grantResults.length > 0
+                && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+            onCameraPermissionGranted();
+        }
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+    }
+}

modules/java/generator/android/java/org/opencv/android/CameraBridgeViewBase.java

@@ -48,6 +48,7 @@ public abstract class CameraBridgeViewBase extends SurfaceView implements Surfac
     protected int mPreviewFormat = RGBA;
     protected int mCameraIndex = CAMERA_ID_ANY;
     protected boolean mEnabled;
+    protected boolean mCameraPermissionGranted = false;
     protected FpsMeter mFpsMeter = null;
 
     public static final int CAMERA_ID_ANY   = -1;
@@ -219,9 +220,24 @@ public abstract class CameraBridgeViewBase extends SurfaceView implements Surfac
         }
     }
 
+
+    /**
+     * This method is provided for clients, so they can signal camera permission has been granted.
+     * The actual onCameraViewStarted callback will be delivered only after setCameraPermissionGranted
+     * and enableView have been called and surface is available
+     */
+    public void setCameraPermissionGranted() {
+        synchronized(mSyncObject) {
+            mCameraPermissionGranted = true;
+            checkCurrentState();
+        }
+    }
+
+
     /**
      * This method is provided for clients, so they can enable the camera connection.
-     * The actual onCameraViewStarted callback will be delivered only after both this method is called and surface is available
+     * The actual onCameraViewStarted callback will be delivered only after setCameraPermissionGranted
+     * and enableView have been called and surface is available
      */
     public void enableView() {
         synchronized(mSyncObject) {
@@ -300,7 +316,7 @@ public abstract class CameraBridgeViewBase extends SurfaceView implements Surfac
         Log.d(TAG, "call checkCurrentState");
         int targetState;
 
-        if (mEnabled && mSurfaceExist && getVisibility() == VISIBLE) {
+        if (mEnabled && mCameraPermissionGranted && mSurfaceExist && getVisibility() == VISIBLE) {
             targetState = STARTED;
         } else {
             targetState = STOPPED;

samples/android/15-puzzle/src/org/opencv/samples/puzzle15/Puzzle15Activity.java

 package org.opencv.samples.puzzle15;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
 import org.opencv.core.Mat;
@@ -9,7 +10,6 @@ import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener;
 import org.opencv.android.JavaCameraView;
 
 import android.os.Bundle;
-import android.app.Activity;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
@@ -17,7 +17,10 @@ import android.view.MotionEvent;
 import android.view.View;
 import android.view.WindowManager;
 
-public class Puzzle15Activity extends Activity implements CvCameraViewListener, View.OnTouchListener {
+import java.util.Collections;
+import java.util.List;
+
+public class Puzzle15Activity extends CameraActivity implements CvCameraViewListener, View.OnTouchListener {
 
     private static final String  TAG = "Sample::Puzzle15::Activity";
 
@@ -86,6 +89,11 @@ public class Puzzle15Activity extends Activity implements CvCameraViewListener,
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)

samples/android/camera-calibration/src/org/opencv/samples/cameracalibration/CameraCalibrationActivity.java

@@ -14,6 +14,7 @@
 package org.opencv.samples.cameracalibration;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
@@ -21,7 +22,6 @@ import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
 import org.opencv.core.Mat;
 
-import android.app.Activity;
 import android.app.ProgressDialog;
 import android.content.res.Resources;
 import android.os.AsyncTask;
@@ -36,12 +36,16 @@ import android.view.View.OnTouchListener;
 import android.view.WindowManager;
 import android.widget.Toast;
 
-public class CameraCalibrationActivity extends Activity implements CvCameraViewListener2, OnTouchListener {
+import java.util.Collections;
+import java.util.List;
+
+public class CameraCalibrationActivity extends CameraActivity implements CvCameraViewListener2, OnTouchListener {
     private static final String TAG = "OCVSample::Activity";
 
     private CameraBridgeViewBase mOpenCvCameraView;
     private CameraCalibrator mCalibrator;
     private OnCameraFrameRender mOnCameraFrameRender;
+    private Menu mMenu;
     private int mWidth;
     private int mHeight;
 
@@ -101,6 +105,11 @@ public class CameraCalibrationActivity extends Activity implements CvCameraViewL
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)
@@ -111,7 +120,7 @@ public class CameraCalibrationActivity extends Activity implements CvCameraViewL
     public boolean onCreateOptionsMenu(Menu menu) {
         super.onCreateOptionsMenu(menu);
         getMenuInflater().inflate(R.menu.calibration, menu);
-
+        mMenu = menu;
         return true;
     }
 
@@ -119,9 +128,9 @@ public class CameraCalibrationActivity extends Activity implements CvCameraViewL
     public boolean onPrepareOptionsMenu (Menu menu) {
         super.onPrepareOptionsMenu(menu);
         menu.findItem(R.id.preview_mode).setEnabled(true);
-        if (!mCalibrator.isCalibrated())
+        if (mCalibrator != null && !mCalibrator.isCalibrated()) {
             menu.findItem(R.id.preview_mode).setEnabled(false);
-
+        }
         return true;
     }
 
@@ -199,6 +208,10 @@ public class CameraCalibrationActivity extends Activity implements CvCameraViewL
             mCalibrator = new CameraCalibrator(mWidth, mHeight);
             if (CalibrationResult.tryLoad(this, mCalibrator.getCameraMatrix(), mCalibrator.getDistortionCoefficients())) {
                 mCalibrator.setCalibrated();
+            } else {
+                if (mMenu != null && !mCalibrator.isCalibrated()) {
+                    mMenu.findItem(R.id.preview_mode).setEnabled(false);
+                }
             }
 
             mOnCameraFrameRender = new OnCameraFrameRender(new CalibrationFrameRender(mCalibrator));

samples/android/color-blob-detection/src/org/opencv/samples/colorblobdetect/ColorBlobDetectionActivity.java

 package org.opencv.samples.colorblobdetect;
 
+import java.util.Collections;
 import java.util.List;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -27,7 +29,7 @@ import android.view.WindowManager;
 import android.view.View.OnTouchListener;
 import android.view.SurfaceView;
 
-public class ColorBlobDetectionActivity extends Activity implements OnTouchListener, CvCameraViewListener2 {
+public class ColorBlobDetectionActivity extends CameraActivity implements OnTouchListener, CvCameraViewListener2 {
     private static final String  TAG              = "OCVSample::Activity";
 
     private boolean              mIsColorSelected = false;
@@ -99,6 +101,11 @@ public class ColorBlobDetectionActivity extends Activity implements OnTouchListe
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)

samples/android/face-detection/src/org/opencv/samples/facedetect/FdActivity.java

@@ -4,8 +4,11 @@ import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.Collections;
+import java.util.List;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -28,7 +31,7 @@ import android.view.Menu;
 import android.view.MenuItem;
 import android.view.WindowManager;
 
-public class FdActivity extends Activity implements CvCameraViewListener2 {
+public class FdActivity extends CameraActivity implements CvCameraViewListener2 {
 
     private static final String    TAG                 = "OCVSample::Activity";
     private static final Scalar    FACE_RECT_COLOR     = new Scalar(0, 255, 0, 255);
@@ -150,6 +153,11 @@ public class FdActivity extends Activity implements CvCameraViewListener2 {
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         mOpenCvCameraView.disableView();

samples/android/image-manipulations/src/org/opencv/samples/imagemanipulations/ImageManipulationsActivity.java

 package org.opencv.samples.imagemanipulations;
 
 import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -18,14 +21,13 @@ import org.opencv.android.CameraBridgeViewBase;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
 import org.opencv.imgproc.Imgproc;
 
-import android.app.Activity;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.WindowManager;
 
-public class ImageManipulationsActivity extends Activity implements CvCameraViewListener2 {
+public class ImageManipulationsActivity extends CameraActivity implements CvCameraViewListener2 {
     private static final String  TAG                 = "OCVSample::Activity";
 
     public static final int      VIEW_MODE_RGBA      = 0;
@@ -121,6 +123,11 @@ public class ImageManipulationsActivity extends Activity implements CvCameraView
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)

samples/android/tutorial-1-camerapreview/src/org/opencv/samples/tutorial1/Tutorial1Activity.java

 package org.opencv.samples.tutorial1;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -8,16 +9,16 @@ import org.opencv.core.Mat;
 import org.opencv.android.CameraBridgeViewBase;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
 
-import android.app.Activity;
 import android.os.Bundle;
 import android.util.Log;
-import android.view.Menu;
 import android.view.MenuItem;
 import android.view.SurfaceView;
 import android.view.WindowManager;
-import android.widget.Toast;
 
-public class Tutorial1Activity extends Activity implements CvCameraViewListener2 {
+import java.util.Collections;
+import java.util.List;
+
+public class Tutorial1Activity extends CameraActivity implements CvCameraViewListener2 {
     private static final String TAG = "OCVSample::Activity";
 
     private CameraBridgeViewBase mOpenCvCameraView;
@@ -82,6 +83,11 @@ public class Tutorial1Activity extends Activity implements CvCameraViewListener2
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)

samples/android/tutorial-2-mixedprocessing/src/org/opencv/samples/tutorial2/Tutorial2Activity.java

 package org.opencv.samples.tutorial2;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -10,14 +11,16 @@ import org.opencv.android.CameraBridgeViewBase;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
 import org.opencv.imgproc.Imgproc;
 
-import android.app.Activity;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.WindowManager;
 
-public class Tutorial2Activity extends Activity implements CvCameraViewListener2 {
+import java.util.Collections;
+import java.util.List;
+
+public class Tutorial2Activity extends CameraActivity implements CvCameraViewListener2 {
     private static final String    TAG = "OCVSample::Activity";
 
     private static final int       VIEW_MODE_RGBA     = 0;
@@ -107,6 +110,11 @@ public class Tutorial2Activity extends Activity implements CvCameraViewListener2
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)

samples/android/tutorial-3-cameracontrol/src/org/opencv/samples/tutorial3/Tutorial3Activity.java

 package org.opencv.samples.tutorial3;
 
 import java.text.SimpleDateFormat;
+import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 import java.util.ListIterator;
 
 import org.opencv.android.BaseLoaderCallback;
+import org.opencv.android.CameraActivity;
+import org.opencv.android.CameraBridgeViewBase;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
 import org.opencv.android.LoaderCallbackInterface;
 import org.opencv.android.OpenCVLoader;
@@ -13,7 +16,6 @@ import org.opencv.core.Mat;
 import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
 
 import android.annotation.SuppressLint;
-import android.app.Activity;
 import android.hardware.Camera.Size;
 import android.os.Bundle;
 import android.os.Environment;
@@ -28,11 +30,14 @@ import android.view.View.OnTouchListener;
 import android.view.WindowManager;
 import android.widget.Toast;
 
-public class Tutorial3Activity extends Activity implements CvCameraViewListener2, OnTouchListener {
+public class Tutorial3Activity extends CameraActivity implements CvCameraViewListener2, OnTouchListener {
     private static final String TAG = "OCVSample::Activity";
 
     private Tutorial3View mOpenCvCameraView;
     private List<Size> mResolutionList;
+    private Menu mMenu;
+    private boolean mCameraStarted = false;
+    private boolean mMenuItemsCreated = false;
     private MenuItem[] mEffectMenuItems;
     private SubMenu mColorEffectsMenu;
     private MenuItem[] mResolutionMenuItems;
@@ -97,13 +102,21 @@ public class Tutorial3Activity extends Activity implements CvCameraViewListener2
         }
     }
 
+    @Override
+    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
+        return Collections.singletonList(mOpenCvCameraView);
+    }
+
     public void onDestroy() {
         super.onDestroy();
         if (mOpenCvCameraView != null)
             mOpenCvCameraView.disableView();
     }
 
+    @Override
     public void onCameraViewStarted(int width, int height) {
+        mCameraStarted = true;
+        setupMenuItems();
     }
 
     public void onCameraViewStopped() {
@@ -115,38 +128,43 @@ public class Tutorial3Activity extends Activity implements CvCameraViewListener2
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
+        mMenu = menu;
+        setupMenuItems();
+        return true;
+    }
+
+    private void setupMenuItems() {
+        if (mMenu == null || !mCameraStarted || mMenuItemsCreated) {
+            return;
+        }
         List<String> effects = mOpenCvCameraView.getEffectList();
 
         if (effects == null) {
             Log.e(TAG, "Color effects are not supported by device!");
-            return true;
+            return;
         }
 
-        mColorEffectsMenu = menu.addSubMenu("Color Effect");
+        mColorEffectsMenu = mMenu.addSubMenu("Color Effect");
         mEffectMenuItems = new MenuItem[effects.size()];
 
         int idx = 0;
         ListIterator<String> effectItr = effects.listIterator();
-        while(effectItr.hasNext()) {
-           String element = effectItr.next();
-           mEffectMenuItems[idx] = mColorEffectsMenu.add(1, idx, Menu.NONE, element);
-           idx++;
+        for (String effect: effects) {
+            mEffectMenuItems[idx] = mColorEffectsMenu.add(1, idx, Menu.NONE, effect);
+            idx++;
         }
 
-        mResolutionMenu = menu.addSubMenu("Resolution");
+        mResolutionMenu = mMenu.addSubMenu("Resolution");
         mResolutionList = mOpenCvCameraView.getResolutionList();
         mResolutionMenuItems = new MenuItem[mResolutionList.size()];
 
-        ListIterator<Size> resolutionItr = mResolutionList.listIterator();
         idx = 0;
-        while(resolutionItr.hasNext()) {
-            Size element = resolutionItr.next();
+        for (Size resolution: mResolutionList) {
             mResolutionMenuItems[idx] = mResolutionMenu.add(2, idx, Menu.NONE,
-                    Integer.valueOf(element.width).toString() + "x" + Integer.valueOf(element.height).toString());
+                    Integer.valueOf(resolution.width).toString() + "x" + Integer.valueOf(resolution.height).toString());
             idx++;
-         }
-
-        return true;
+        }
+        mMenuItemsCreated = true;
     }
 
     public boolean onOptionsItemSelected(MenuItem item) {