Better auto-focus

This simplifies the API by removing focusMode and introducing autoFocus.
Pictures are now taken right after auto-focus.  Also remove external
camera support as there is no easy way to support it for API Level <21.

The demo app now has a button to switch camera.

Change-Id: If978959d2095632c332d17ab7f99e6ed18d82057

demo/src/main/java/com/google/android/cameraview/demo/MainActivity.java

@@ -33,9 +33,13 @@
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.app.DialogFragment;
 import android.support.v4.content.ContextCompat;
+import android.support.v7.app.ActionBar;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
+import android.support.v7.widget.Toolbar;
 import android.util.Log;
+import android.view.Menu;
+import android.view.MenuItem;
 import android.view.View;
 import android.widget.Toast;
 
@@ -100,6 +104,12 @@ protected void onCreate(Bundle savedInstanceState) {
         if (takePicture != null) {
             takePicture.setOnClickListener(mOnClickListener);
         }
+        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
+        setSupportActionBar(toolbar);
+        ActionBar actionBar = getSupportActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayShowTitleEnabled(false);
+        }
     }
 
     @Override
@@ -167,6 +177,26 @@ public void onRequestPermissionsResult(int requestCode, @NonNull String[] permis
         }
     }
 
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        getMenuInflater().inflate(R.menu.main, menu);
+        return true;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case R.id.switch_camera:
+                if (mCameraView != null) {
+                    int facing = mCameraView.getFacing();
+                    mCameraView.setFacing(facing == CameraView.FACING_FRONT ?
+                            CameraView.FACING_BACK : CameraView.FACING_FRONT);
+                }
+                break;
+        }
+        return false;
+    }
+
     private Handler getBackgroundHandler() {
         if (mBackgroundHandler == null) {
             HandlerThread thread = new HandlerThread("background");

demo/src/main/res/drawable/ic_switch_camera.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright (C) 2016 The Android Open Source Project
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+         http://www.apache.org/licenses/LICENSE-2.0
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FFFFFFFF"
+        android:pathData="M20,4h-3.17L15,2L9,2L7.17,4L4,4c-1.1,0 -2,0.9 -2,2v12c0,1.1 0.9,2 2,2h16c1.1,0 2,-0.9 2,-2L22,6c0,-1.1 -0.9,-2 -2,-2zM15,15.5L15,13L9,13v2.5L5.5,12 9,8.5L9,11h6L15,8.5l3.5,3.5 -3.5,3.5z"/>
+</vector>

demo/src/main/res/layout/include_camera.xml

@@ -11,12 +11,20 @@
     See the License for the specific language governing permissions and
     limitations under the License.
 -->
-<com.google.android.cameraview.CameraView
-    android:id="@+id/camera"
+<FrameLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:adjustViewBounds="true"
-    app:facing="back"
-    app:focusMode="continuousPicture"/>
+    android:layout_height="match_parent">
+
+    <com.google.android.cameraview.CameraView
+        android:id="@+id/camera"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:adjustViewBounds="true"/>
+
+    <android.support.v7.widget.Toolbar
+        android:id="@+id/toolbar"
+        android:layout_width="match_parent"
+        android:layout_height="?attr/actionBarSize"/>
+
+</FrameLayout>

demo/src/main/res/menu/main.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright (C) 2016 The Android Open Source Project
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+         http://www.apache.org/licenses/LICENSE-2.0
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+<menu
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <item
+        android:id="@+id/switch_camera"
+        android:icon="@drawable/ic_switch_camera"
+        android:title="@string/switch_camera"
+        app:showAsAction="ifRoom"/>
+
+</menu>

demo/src/main/res/values/strings.xml

@@ -18,4 +18,5 @@
     <string name="storage_permission_confirmation">This app saves taken photos to external storage.</string>
     <string name="storage_permission_not_granted">The app does not have permission to save a photo.</string>
     <string name="picture_taken">Picture taken</string>
+    <string name="switch_camera">Switch camera</string>
 </resources>

library/src/androidTest/java/com/google/android/cameraview/CameraViewTest.java

@@ -109,6 +109,22 @@ public void check(View view, NoMatchingViewException noViewFoundException) {
                         CameraView cameraView = (CameraView) view;
                         AspectRatio ratio = cameraView.getAspectRatio();
                         assertThat(ratio, is(notNullValue()));
+                        Set<AspectRatio> ratios = cameraView.getSupportedAspectRatios();
+                        assertThat(ratios.size(), is(greaterThanOrEqualTo(1)));
+                        assertThat(ratios, hasItem(ratio));
+                        if (ratios.size() == 1) {
+                            return;
+                        }
+                        // Pick one ratio to change to
+                        for (AspectRatio r : ratios) {
+                            if (!r.equals(ratio)) {
+                                ratio = r;
+                                break;
+                            }
+                        }
+                        assert ratio != null;
+                        cameraView.setAspectRatio(ratio);
+                        assertThat(cameraView.getAspectRatio(), is(equalTo(ratio)));
                     }
                 });
     }
@@ -163,16 +179,18 @@ public void check(View view, NoMatchingViewException noViewFoundException) {
     }
 
     @Test
-    public void testFocusMode() {
+    public void testAutoFocus() {
         onView(withId(R.id.camera))
                 .check(new ViewAssertion() {
                     @Override
                     public void check(View view, NoMatchingViewException noViewFoundException) {
                         CameraView cameraView = (CameraView) view;
-                        assertThat(cameraView.getFocusMode(), is(CameraView.FOCUS_MODE_OFF));
-                        cameraView.setFocusMode(CameraView.FOCUS_MODE_CONTINUOUS_PICTURE);
-                        assertThat(cameraView.getFocusMode(),
-                                is(CameraView.FOCUS_MODE_CONTINUOUS_PICTURE));
+                        // This can fail on devices without auto-focus support
+                        assertThat(cameraView.getAutoFocus(), is(true));
+                        cameraView.setAutoFocus(false);
+                        assertThat(cameraView.getAutoFocus(), is(false));
+                        cameraView.setAutoFocus(true);
+                        assertThat(cameraView.getAutoFocus(), is(true));
                     }
                 });
     }

library/src/main/base/com/google/android/cameraview/CameraViewImpl.java

@@ -18,6 +18,8 @@
 
 import android.view.TextureView;
 
+import java.util.Set;
+
 abstract class CameraViewImpl {
 
     protected final Callback mCallback;
@@ -34,13 +36,15 @@ public CameraViewImpl(Callback callback) {
 
     abstract boolean isCameraOpened();
 
+    abstract Set<AspectRatio> getSupportedAspectRatios();
+
     abstract void setAspectRatio(AspectRatio ratio);
 
     abstract AspectRatio getAspectRatio();
 
-    abstract void setFocusMode(int focusMode);
+    abstract void setAutoFocus(boolean autoFocus);
 
-    abstract int getFocusMode();
+    abstract boolean getAutoFocus();
 
     abstract void setFacing(int facing);
 

library/src/main/base/com/google/android/cameraview/Constants.java

@@ -19,15 +19,7 @@
 
 interface Constants {
 
-    int FOCUS_MODE_OFF = 0;
-    int FOCUS_MODE_AUTO = 1;
-    int FOCUS_MODE_MACRO = 2;
-    int FOCUS_MODE_CONTINUOUS_PICTURE = 3;
-    int FOCUS_MODE_CONTINUOUS_VIDEO = 4;
-    int FOCUS_MODE_EDOF = 5;
-
     int FACING_BACK = 0;
     int FACING_FRONT = 1;
-    int FACING_EXTERNAL = 2;
 
 }

library/src/main/camera1/com/google/android/cameraview/Camera1.java

@@ -21,6 +21,7 @@
 import android.view.TextureView;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Set;
 import java.util.SortedSet;
 
@@ -49,7 +50,7 @@ class Camera1 extends CameraViewImpl {
 
     private boolean mShowingPreview;
 
-    private int mFocusMode;
+    private boolean mAutoFocus;
 
     private int mFacing;
 
@@ -141,6 +142,11 @@ boolean isCameraOpened() {
         return mCamera != null;
     }
 
+    @Override
+    Set<AspectRatio> getSupportedAspectRatios() {
+        return mPreviewSizes.ratios();
+    }
+
     @Override
     void setAspectRatio(AspectRatio ratio) {
         if (mAspectRatio == null || !isCameraOpened()) {
@@ -163,29 +169,30 @@ AspectRatio getAspectRatio() {
     }
 
     @Override
-    void setFocusMode(int focusMode) {
-        if (mFocusMode != focusMode) {
-            mFocusMode = focusMode;
-            if (mCamera != null) {
-                mCameraParameters.setFocusMode(Camera1Constants.convertFocusMode(focusMode));
-                mCamera.setParameters(mCameraParameters);
-            }
+    void setAutoFocus(boolean autoFocus) {
+        if (mAutoFocus == autoFocus) {
+            return;
+        }
+        if (setAutoFocusInternal(autoFocus)) {
+            mCamera.setParameters(mCameraParameters);
         }
     }
 
     @Override
-    int getFocusMode() {
-        return mFocusMode;
+    boolean getAutoFocus() {
+        String focusMode = mCameraParameters.getFocusMode();
+        return focusMode != null && focusMode.contains("continuous");
     }
 
     @Override
     void setFacing(int facing) {
-        if (mFacing != facing) {
-            mFacing = facing;
-            if (mCamera != null) {
-                stop();
-                start();
-            }
+        if (mFacing == facing) {
+            return;
+        }
+        mFacing = facing;
+        if (isCameraOpened()) {
+            stop();
+            start();
         }
     }
 
@@ -199,6 +206,20 @@ void takePicture() {
         if (!isCameraOpened()) {
             throw new IllegalStateException("Camera is not ready. Call start() before takePicture().");
         }
+        if (getAutoFocus()) {
+            mCamera.cancelAutoFocus();
+            mCamera.autoFocus(new Camera.AutoFocusCallback() {
+                @Override
+                public void onAutoFocus(boolean success, Camera camera) {
+                    takePictureInternal();
+                }
+            });
+        } else {
+            takePictureInternal();
+        }
+    }
+
+    private void takePictureInternal() {
         mCamera.takePicture(null, null, null, new Camera.PictureCallback() {
             @Override
             public void onPictureTaken(byte[] data, Camera camera) {
@@ -285,7 +306,7 @@ private void adjustCameraParameters() {
             mCameraParameters.setPreviewSize(size.getWidth(), size.getHeight());
             mCameraParameters.setPictureSize(pictureSize.getWidth(), pictureSize.getHeight());
             mCameraParameters.setRotation(calcCameraRotation(mDisplayOrientation));
-            mCameraParameters.setFocusMode(Camera1Constants.convertFocusMode(mFocusMode));
+            setAutoFocusInternal(mAutoFocus);
             mCamera.setParameters(mCameraParameters);
             if (mShowingPreview) {
                 mCamera.startPreview();
@@ -334,4 +355,26 @@ private int calcCameraRotation(int rotation) {
         }
     }
 
+    /**
+     * @return {@code true} if {@link #mCameraParameters} was modified.
+     */
+    private boolean setAutoFocusInternal(boolean autoFocus) {
+        mAutoFocus = autoFocus;
+        if (isCameraOpened()) {
+            final List<String> modes = mCameraParameters.getSupportedFocusModes();
+            if (autoFocus && modes.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) {
+                mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
+            } else if (modes.contains(Camera.Parameters.FOCUS_MODE_FIXED)) {
+                mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_FIXED);
+            } else if (modes.contains(Camera.Parameters.FOCUS_MODE_INFINITY)) {
+                mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_INFINITY);
+            } else {
+                mCameraParameters.setFocusMode(modes.get(0));
+            }
+            return true;
+        } else {
+            return false;
+        }
+    }
+
 }