Pinch to zoom (RedApparat#388)

* Update gradle and libs

* Implemented pinch to zoom in example app

build.gradle

@@ -9,8 +9,7 @@ subprojects {
 buildscript {
     ext {
         versions = [
-                gradle : '4.10.2',
-                kotlin : '1.3.0',
+                kotlin : '1.3.50',
                 code   : 1,
                 name   : '1.0.0',
                 sdk    : [
@@ -19,13 +18,13 @@ buildscript {
                 ],
                 android: [
                         buildTools: '28.0.3',
-                        appcompat   : '1.0.1',
-                        annotation   : '1.0.0',
+                        appcompat   : '1.1.0',
+                        annotation   : '1.1.0',
                         exifinterface : '1.0.0'
                 ],
                 rx     : [
                         rxJava1: '1.3.8',
-                        rxJava2: '2.2.3'
+                        rxJava2: '2.2.12'
                 ],
                 test   : [
                         junit  : '4.12',
@@ -38,7 +37,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.0'
+        classpath 'com.android.tools.build:gradle:3.5.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${versions.kotlin}"
 
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
@@ -57,6 +56,3 @@ task clean(type: Delete) {
     delete rootProject.buildDir
 }
 
-task wrapper(type: Wrapper) {
-    gradleVersion = versions.gradle
-}

fotoapparat/build.gradle

@@ -32,7 +32,7 @@ dependencies {
     implementation "androidx.annotation:annotation:${versions.android.annotation}"
     implementation "androidx.exifinterface:exifinterface:${versions.android.exifinterface}"
     implementation "org.jetbrains.kotlin:kotlin-stdlib:${versions.kotlin}"
-    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.0.0'
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0'
     testImplementation "junit:junit:${versions.test.junit}"
     testImplementation "org.jetbrains.kotlin:kotlin-test-junit:${versions.kotlin}"
     testImplementation "org.mockito:mockito-core:${versions.test.mockito}"

fotoapparat/src/main/java/io/fotoapparat/coroutines/AwaitBroadcastChannel.kt

@@ -1,13 +1,13 @@
 package io.fotoapparat.coroutines
 
-import kotlinx.coroutines.CompletableDeferred
-import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.*
 import kotlinx.coroutines.channels.BroadcastChannel
 import kotlinx.coroutines.channels.ConflatedBroadcastChannel
 
 /**
  * A [ConflatedBroadcastChannel] which exposes a [getValue] which will [await] for at least one value.
  */
+@ExperimentalCoroutinesApi
 internal class AwaitBroadcastChannel<T>(
         private val channel: ConflatedBroadcastChannel<T> = ConflatedBroadcastChannel(),
         private val deferred: CompletableDeferred<Boolean> = CompletableDeferred()
@@ -31,7 +31,13 @@ internal class AwaitBroadcastChannel<T>(
         channel.send(element)
     }
 
+    override fun cancel(cause: CancellationException?) {
+        channel.cancel(cause)
+        deferred.cancel(cause)
+    }
+
     override fun cancel(cause: Throwable?): Boolean {
-        return channel.cancel(cause) && deferred.cancel(cause)
+        deferred.cancel(cause?.message ?:"", cause)
+        return channel.close(cause)
     }
 }

fotoapparat/src/main/java/io/fotoapparat/view/FocusView.kt

@@ -5,6 +5,7 @@ import android.content.Context
 import android.util.AttributeSet
 import android.view.GestureDetector
 import android.view.MotionEvent
+import android.view.ScaleGestureDetector
 import android.widget.FrameLayout
 import io.fotoapparat.hardware.metering.FocalRequest
 import io.fotoapparat.hardware.metering.PointF
@@ -15,7 +16,7 @@ import io.fotoapparat.parameter.Resolution
  *
  * If the camera doesn't support focus metering on specific area this will only display a visual feedback.
  */
-class FocusView
+open class FocusView
 @JvmOverloads constructor(
         context: Context,
         attrs: AttributeSet? = null,
@@ -25,6 +26,15 @@ class FocusView
     private val visualFeedbackCircle = FeedbackCircleView(context, attrs, defStyleAttr)
     private var focusMeteringListener: ((FocalRequest) -> Unit)? = null
 
+    var scaleListener: ((Float) -> Unit)? = null
+    var ptrListener: ((Int) -> Unit)? = null
+
+    private var mPtrCount: Int = 0
+        set(value) {
+            field = value
+            ptrListener?.invoke(value)
+        }
+
     init {
         clipToPadding = false
         clipChildren = false
@@ -38,6 +48,14 @@ class FocusView
     @SuppressLint("ClickableViewAccessibility")
     override fun onTouchEvent(event: MotionEvent): Boolean {
         tapDetector.onTouchEvent(event)
+        scaleDetector.onTouchEvent(event)
+
+        when (event.action and MotionEvent.ACTION_MASK) {
+            MotionEvent.ACTION_POINTER_DOWN -> mPtrCount++
+            MotionEvent.ACTION_POINTER_UP -> mPtrCount--
+            MotionEvent.ACTION_DOWN -> mPtrCount++
+            MotionEvent.ACTION_UP -> mPtrCount--
+        }
         return true
     }
 
@@ -64,4 +82,15 @@ class FocusView
     }
 
     private val tapDetector = GestureDetector(context, gestureDetectorListener)
+
+    private val scaleGestureDetector = object : ScaleGestureDetector.SimpleOnScaleGestureListener() {
+        override fun onScale(detector: ScaleGestureDetector): Boolean {
+            return scaleListener
+                    ?.let {
+                        it(detector.scaleFactor)
+                        true
+                    }?: super.onScale(detector)
+        }
+    }
+    private val scaleDetector = ScaleGestureDetector(context, scaleGestureDetector)
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.2-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip

sample/src/main/java/io/fotoapparat/sample/ActivityJava.java

@@ -5,30 +5,35 @@
 import android.view.View;
 import android.widget.CompoundButton;
 import android.widget.ImageView;
-import android.widget.SeekBar;
+import android.widget.TextView;
 import android.widget.Toast;
 
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
+import java.util.Locale;
 
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.SwitchCompat;
 import io.fotoapparat.Fotoapparat;
+import io.fotoapparat.capability.Capabilities;
 import io.fotoapparat.configuration.CameraConfiguration;
 import io.fotoapparat.configuration.UpdateConfiguration;
 import io.fotoapparat.error.CameraErrorListener;
 import io.fotoapparat.exception.camera.CameraException;
 import io.fotoapparat.parameter.ScaleType;
+import io.fotoapparat.parameter.Zoom;
 import io.fotoapparat.preview.Frame;
 import io.fotoapparat.preview.FrameProcessor;
 import io.fotoapparat.result.BitmapPhoto;
 import io.fotoapparat.result.PhotoResult;
 import io.fotoapparat.result.WhenDoneListener;
 import io.fotoapparat.view.CameraView;
 import io.fotoapparat.view.FocusView;
+import kotlin.Unit;
+import kotlin.jvm.functions.Function1;
 
 import static io.fotoapparat.log.LoggersKt.fileLogger;
 import static io.fotoapparat.log.LoggersKt.logcat;
@@ -57,9 +62,13 @@ public class ActivityJava extends AppCompatActivity {
     private boolean hasCameraPermission;
     private CameraView cameraView;
     private FocusView focusView;
+    private TextView zoomLvl;
+    private ImageView switchCamera;
     private View capture;
 
     private Fotoapparat fotoapparat;
+    private Zoom.VariableZoom cameraZoom;
+    private float curZoom = 0f;
 
     boolean activeCameraBack = true;
 
@@ -92,6 +101,8 @@ protected void onCreate(Bundle savedInstanceState) {
         cameraView = findViewById(R.id.cameraView);
         focusView = findViewById(R.id.focusView);
         capture = findViewById(R.id.capture);
+        zoomLvl = findViewById(R.id.zoomLvl);
+        switchCamera = findViewById(R.id.switchCamera);
         hasCameraPermission = permissionsDelegate.hasCameraPermission();
 
         if (hasCameraPermission) {
@@ -105,7 +116,6 @@ protected void onCreate(Bundle savedInstanceState) {
         takePictureOnClick();
         switchCameraOnClick();
         toggleTorchOnSwitch();
-        zoomSeekBar();
     }
 
     private Fotoapparat createFotoapparat() {
@@ -129,15 +139,66 @@ public void onError(@NotNull CameraException e) {
                 .build();
     }
 
-    private void zoomSeekBar() {
-        SeekBar seekBar = findViewById(R.id.zoomSeekBar);
-
-        seekBar.setOnSeekBarChangeListener(new OnProgressChanged() {
+    private void adjustViewsVisibility() {
+        fotoapparat.getCapabilities().whenAvailable(new Function1<Capabilities, Unit>() {
             @Override
-            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
-                fotoapparat.setZoom(progress / (float) seekBar.getMax());
+            public Unit invoke(Capabilities capabilities) {
+                Zoom zoom = capabilities != null ? capabilities.getZoom() : null;
+                if(zoom instanceof Zoom.VariableZoom){
+                    cameraZoom = (Zoom.VariableZoom) zoom;
+                    focusView.setScaleListener(new Function1<Float, Unit>() {
+                        @Override
+                        public Unit invoke(Float aFloat) {
+                            scaleZoom(aFloat);
+                            return null;
+                        }
+                    });
+                    focusView.setPtrListener(new Function1<Integer, Unit>() {
+                        @Override
+                        public Unit invoke(Integer integer) {
+                            pointerChanged(integer);
+                            return null;
+                        }
+                    });
+                } else {
+                    zoomLvl.setVisibility(View.GONE);
+                    focusView.setScaleListener(null);
+                    focusView.setPtrListener(null);
+                }
+                return null;
             }
         });
+        if (fotoapparat.isAvailable(front())){
+            switchCamera.setVisibility(View.VISIBLE);
+        } else {
+            switchCamera.setVisibility(View.GONE);
+        }
+    }
+
+    private void scaleZoom(float scaleFactor){
+        float plusZoom = 0;
+        if (scaleFactor < 1) plusZoom = -1 * (1 - scaleFactor);
+        else plusZoom = scaleFactor - 1;
+
+        float newZoom = curZoom + plusZoom;
+        if (newZoom < 0 || newZoom > 1) return;
+
+        curZoom = newZoom;
+        fotoapparat.setZoom(curZoom);
+
+        int progress = Math.round (cameraZoom.getMaxZoom() * curZoom);
+        int value = cameraZoom.getZoomRatios().get(progress);
+
+        float roundedValue = (float)(Math.round(((float)value) / 10f)) / 10f;
+
+        zoomLvl.setVisibility(View.VISIBLE);
+        zoomLvl.setText(String.format(Locale.getDefault(), "%.1f×", roundedValue));
+    }
+
+    private void pointerChanged(int fingerCount){
+        if(fingerCount == 0) {
+            zoomLvl.setVisibility(View.GONE);
+        }
     }
 
     private void switchCameraOnClick() {
@@ -180,6 +241,7 @@ public void onClick(View v) {
                         activeCameraBack ? back() : front(),
                         cameraConfiguration
                 );
+                adjustViewsVisibility();
             }
         });
     }
@@ -223,6 +285,7 @@ protected void onStart() {
         super.onStart();
         if (hasCameraPermission) {
             fotoapparat.start();
+            adjustViewsVisibility();
         }
     }
 
@@ -242,6 +305,7 @@ public void onRequestPermissionsResult(int requestCode,
         if (permissionsDelegate.resultGranted(requestCode, permissions, grantResults)) {
             hasCameraPermission = true;
             fotoapparat.start();
+            adjustViewsVisibility();
             cameraView.setVisibility(View.VISIBLE);
         }
     }

sample/src/main/java/io/fotoapparat/sample/MainActivity.kt

@@ -28,6 +28,8 @@ class MainActivity : AppCompatActivity() {
     private lateinit var fotoapparat: Fotoapparat
     private lateinit var cameraZoom: Zoom.VariableZoom
 
+    private var curZoom: Float = 0f
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
@@ -148,8 +150,16 @@ class MainActivity : AppCompatActivity() {
                     capabilities
                             ?.let {
                                 (it.zoom as? Zoom.VariableZoom)
-                                        ?.let { zoom -> setupZoom(zoom) }
-                                        ?: run { zoomSeekBar.visibility = View.GONE }
+                                        ?.let {
+                                            cameraZoom = it
+                                            focusView.scaleListener = this::scaleZoom
+                                            focusView.ptrListener = this::pointerChanged
+                                        }
+                                        ?: run {
+                                            zoomLvl?.visibility = View.GONE
+                                            focusView.scaleListener = null
+                                            focusView.ptrListener = null
+                                        }
 
                                 torchSwitch.visibility = if (it.flashModes.contains(Flash.Torch)) View.VISIBLE else View.GONE
                             }
@@ -159,19 +169,27 @@ class MainActivity : AppCompatActivity() {
         switchCamera.visibility = if (fotoapparat.isAvailable(front())) View.VISIBLE else View.GONE
     }
 
-    private fun setupZoom(zoom: Zoom.VariableZoom) {
-        zoomSeekBar.max = zoom.maxZoom
-        cameraZoom = zoom
-        zoomSeekBar.visibility = View.VISIBLE
-        zoomSeekBar onProgressChanged { updateZoom(zoomSeekBar.progress) }
-        updateZoom(0)
-    }
+    //When zooming slowly, the values are approximately 0.9 ~ 1.1
+    private fun scaleZoom(scaleFactor: Float) {
+        //convert to -0.1 ~ 0.1
+        val plusZoom = if (scaleFactor < 1) -1 * (1 - scaleFactor) else scaleFactor - 1
+        val newZoom = curZoom + plusZoom
+        if (newZoom < 0 || newZoom > 1) return
 
-    private fun updateZoom(progress: Int) {
-        fotoapparat.setZoom(progress.toFloat() / zoomSeekBar.max)
+        curZoom = newZoom
+        fotoapparat.setZoom(curZoom)
+        val progress = (cameraZoom.maxZoom * curZoom).roundToInt()
         val value = cameraZoom.zoomRatios[progress]
         val roundedValue = ((value.toFloat()) / 10).roundToInt().toFloat() / 10
-        zoomLvl.text = String.format("%.1f ×", roundedValue)
+
+        zoomLvl.visibility = View.VISIBLE
+        zoomLvl.text = String.format("%.1f×", roundedValue)
+    }
+
+    private fun pointerChanged(fingerCount: Int){
+        if(fingerCount == 0) {
+            zoomLvl?.visibility = View.GONE
+        }
     }
 }