Add test cases for BalanceSeekBar

Bug: 123722274
Test: Manual
      make RunSettingsRoboTests ROBOTEST_FILTER=BalanceSeekBar

Change-Id: Ie6b560b2f92d78a0d3bd7ddb0e0d0a85c7803827

src/com/android/settings/accessibility/BalanceSeekBar.java

@@ -28,6 +28,8 @@ import android.provider.Settings;
 import android.util.AttributeSet;
 import android.widget.SeekBar;
 
+import androidx.annotation.VisibleForTesting;
+
 import com.android.settings.R;
 
 /**
@@ -37,14 +39,13 @@ import com.android.settings.R;
  * Updates Settings.System for balance on progress changed.
  */
 public class BalanceSeekBar extends SeekBar {
-    private static final String TAG = "BalanceSeekBar";
     private final Context mContext;
     private final Object mListenerLock = new Object();
     private OnSeekBarChangeListener mOnSeekBarChangeListener;
     private final OnSeekBarChangeListener mProxySeekBarListener = new OnSeekBarChangeListener() {
         @Override
         public void onStopTrackingTouch(SeekBar seekBar) {
-            synchronized(mListenerLock) {
+            synchronized (mListenerLock) {
                 if (mOnSeekBarChangeListener != null) {
                     mOnSeekBarChangeListener.onStopTrackingTouch(seekBar);
                 }
@@ -53,7 +54,7 @@ public class BalanceSeekBar extends SeekBar {
 
         @Override
         public void onStartTrackingTouch(SeekBar seekBar) {
-            synchronized(mListenerLock) {
+            synchronized (mListenerLock) {
                 if (mOnSeekBarChangeListener != null) {
                     mOnSeekBarChangeListener.onStartTrackingTouch(seekBar);
                 }
@@ -79,7 +80,7 @@ public class BalanceSeekBar extends SeekBar {
 
             // after adjusting the seekbar, notify downstream listener.
             // note that progress may have been adjusted in the code above to mCenter.
-            synchronized(mListenerLock) {
+            synchronized (mListenerLock) {
                 if (mOnSeekBarChangeListener != null) {
                     mOnSeekBarChangeListener.onProgressChanged(seekBar, progress, fromUser);
                 }
@@ -88,7 +89,8 @@ public class BalanceSeekBar extends SeekBar {
     };
 
     // Percentage of max to be used as a snap to threshold
-    private static final float SNAP_TO_PERCENTAGE = 0.03f;
+    @VisibleForTesting
+    static final float SNAP_TO_PERCENTAGE = 0.03f;
     private final Paint mCenterMarkerPaint;
     private final Rect mCenterMarkerRect;
     // changed in setMax()
@@ -122,7 +124,7 @@ public class BalanceSeekBar extends SeekBar {
 
     @Override
     public void setOnSeekBarChangeListener(OnSeekBarChangeListener listener) {
-        synchronized(mListenerLock) {
+        synchronized (mListenerLock) {
             mOnSeekBarChangeListener = listener;
         }
     }
@@ -148,5 +150,10 @@ public class BalanceSeekBar extends SeekBar {
         canvas.restore();
         super.onDraw(canvas);
     }
+
+    @VisibleForTesting
+    OnSeekBarChangeListener getProxySeekBarListener() {
+        return mProxySeekBarListener;
+    }
 }
 

src/com/android/settings/accessibility/BalanceSeekBarPreference.java

@@ -34,7 +34,9 @@ import com.android.settings.widget.SeekBarPreference;
 
 /** A slider preference that directly controls audio balance **/
 public class BalanceSeekBarPreference extends SeekBarPreference {
-    private static final String TAG = "BalanceSeekBarPreference";
+    private static final int BALANCE_CENTER_VALUE = 100;
+    private static final int BALANCE_MAX_VALUE = 200;
+
     private final Context mContext;
     private BalanceSeekBar mSeekBar;
     private ImageView mIconView;
@@ -62,9 +64,9 @@ public class BalanceSeekBarPreference extends SeekBarPreference {
         final float balance = Settings.System.getFloatForUser(
                 mContext.getContentResolver(), Settings.System.MASTER_BALANCE,
                 0.f /* default */, UserHandle.USER_CURRENT);
-        // Rescale balance to range 0-200 centered at 100.
+        // Rescale balance to range 0-BALANCE_MAX_VALUE centered at BALANCE_MAX_VALUE / 2.
-        mSeekBar.setMax(200);
+        mSeekBar.setMax(BALANCE_MAX_VALUE);
-        mSeekBar.setProgress((int)(balance * 100.f) + 100);
+        mSeekBar.setProgress((int) (balance * 100.f) + BALANCE_CENTER_VALUE);
         mSeekBar.setEnabled(isEnabled());
     }
 }

tests/robotests/src/com/android/settings/accessibility/BalanceSeekBarPreferenceTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+package com.android.settings.accessibility;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.LinearLayout;
+
+import androidx.preference.PreferenceViewHolder;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(RobolectricTestRunner.class)
+public class BalanceSeekBarPreferenceTest {
+    private static final int BALANCE_CENTER_VALUE = 100;
+    private static final int BALANCE_MAX_VALUE = 200;
+
+    private Context mContext;
+    private AttributeSet mAttrs;
+    private PreferenceViewHolder mHolder;
+    private BalanceSeekBar mSeekBar;
+    private BalanceSeekBarPreference mSeekBarPreference;
+
+    @Before
+    public void setUp() {
+        mContext = RuntimeEnvironment.application;
+        mSeekBarPreference = new BalanceSeekBarPreference(mContext, mAttrs);
+        LayoutInflater inflater = LayoutInflater.from(mContext);
+        final View view =
+                inflater.inflate(mSeekBarPreference.getLayoutResource(),
+                        new LinearLayout(mContext), false);
+        mHolder = PreferenceViewHolder.createInstanceForTests(view);
+        mSeekBar = (BalanceSeekBar) view.findViewById(com.android.internal.R.id.seekbar);
+    }
+
+    @Test
+    public void seekBarPreferenceOnBindViewHolder_shouldInitSeekBarValue() {
+        mSeekBarPreference.onBindViewHolder(mHolder);
+
+        assertThat(mSeekBar.getMax()).isEqualTo(BALANCE_MAX_VALUE);
+        assertThat(mSeekBar.getProgress()).isEqualTo(BALANCE_CENTER_VALUE);
+    }
+}

tests/robotests/src/com/android/settings/accessibility/BalanceSeekBarTest.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+package com.android.settings.accessibility;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.widget.SeekBar;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.RuntimeEnvironment;
+
+@RunWith(RobolectricTestRunner.class)
+public class BalanceSeekBarTest {
+    // Fix the maximum process value to 200 for testing the BalanceSeekBar.
+    // It affects the SeekBar value of center(100) and snapThreshold(200 * SNAP_TO_PERCENTAGE).
+    private static final int MAX_PROGRESS_VALUE = 200;
+
+    private Context mContext;
+    private AttributeSet mAttrs;
+    private BalanceSeekBar mSeekBar;
+    private BalanceSeekBar.OnSeekBarChangeListener mProxySeekBarListener;
+    private SeekBar.OnSeekBarChangeListener mockSeekBarChangeListener;
+
+    @Before
+    public void setUp() {
+        mContext = RuntimeEnvironment.application;
+        mSeekBar = new BalanceSeekBar(mContext, mAttrs);
+        mProxySeekBarListener = mSeekBar.getProxySeekBarListener();
+        mockSeekBarChangeListener = mock(SeekBar.OnSeekBarChangeListener.class);
+        mSeekBar.setOnSeekBarChangeListener(mockSeekBarChangeListener);
+    }
+
+    @Test
+    public void onStartTrackingTouch_shouldInvokeMethod() {
+        mProxySeekBarListener.onStartTrackingTouch(mSeekBar);
+
+        verify(mockSeekBarChangeListener, times(1)).onStartTrackingTouch(mSeekBar);
+    }
+
+    @Test
+    public void onStopTrackingTouch_shouldInvokeMethod() {
+        mProxySeekBarListener.onStopTrackingTouch(mSeekBar);
+
+        verify(mockSeekBarChangeListener, times(1)).onStopTrackingTouch(mSeekBar);
+    }
+
+    @Test
+    public void onProgressChanged_shouldInvokeMethod() {
+        // Assign the test value of SeekBar progress
+        mProxySeekBarListener.onProgressChanged(mSeekBar, MAX_PROGRESS_VALUE, true);
+
+        verify(mockSeekBarChangeListener, times(1)).onProgressChanged(eq(mSeekBar),
+                eq(MAX_PROGRESS_VALUE), eq(true));
+    }
+
+    @Test
+    public void setMaxTest_shouldSetValue() {
+        mSeekBar.setMax(MAX_PROGRESS_VALUE);
+
+        assertThat(getBalanceSeekBarCenter(mSeekBar)).isEqualTo(MAX_PROGRESS_VALUE / 2);
+        assertThat(getBalanceSeekBarSnapThreshold(mSeekBar)).isEqualTo(
+                MAX_PROGRESS_VALUE * BalanceSeekBar.SNAP_TO_PERCENTAGE);
+    }
+
+    @Test
+    public void setProgressTest_shouldSnapToCenter() {
+        // Assign the test value of SeekBar progress within the threshold (94-106 in this case).
+        final int progressWithinThreshold = 102;
+        mSeekBar.setMax(MAX_PROGRESS_VALUE);
+        mSeekBar.setProgress(progressWithinThreshold + 10); //set progress which is over threshold.
+        mProxySeekBarListener.onProgressChanged(mSeekBar, progressWithinThreshold, true);
+
+        assertThat(mSeekBar.getProgress()).isEqualTo(getBalanceSeekBarCenter(mSeekBar));
+    }
+
+    @Test
+    public void setProgressTest_shouldMaintainInputValue() {
+        // Assign the test value of SeekBar progress without the threshold.
+        final int progressWithoutThreshold = 107;
+        mSeekBar.setMax(MAX_PROGRESS_VALUE);
+        mSeekBar.setProgress(progressWithoutThreshold);
+        mProxySeekBarListener.onProgressChanged(mSeekBar, progressWithoutThreshold, true);
+
+        assertThat(mSeekBar.getProgress()).isEqualTo(progressWithoutThreshold);
+    }
+
+    // method to get the center from BalanceSeekBar for testing setMax().
+    private int getBalanceSeekBarCenter(BalanceSeekBar seekBar) {
+        return seekBar.getMax() / 2;
+    }
+
+    // method to get the snapThreshold from BalanceSeekBar for testing setMax().
+    private float getBalanceSeekBarSnapThreshold(BalanceSeekBar seekBar) {
+        return seekBar.getMax() * BalanceSeekBar.SNAP_TO_PERCENTAGE;
+    }
+}