Disabled state UI of Flash Notifications preview button

When both the camera flash and screen flash toggles are turned off, tapping on the preview button will have no effect and may confuse users. To avoid this, the appearance of the preview button should be updated to clearly indicated that its current state is disabled. This wil help users better understand the situation and prevent confusion.

Bug: 276494146
Test: checks the UI manually
Test: make RunSettingsRoboTests ROBOTEST_FILTER=FlashNotificationsPreviewPreferenceTest
Change-Id: I55b11188fde6e551921a9b0f7c89daa20a8b766b

color-check-baseline.xml

@@ -1581,6 +1581,22 @@
             column="5"/>
     </issue>
 
+    <issue
+        id="HardCodedColor"
+        severity="Error"
+        message="Avoid using hardcoded color"
+        category="Correctness"
+        priority="4"
+        summary="Using hardcoded color"
+        explanation="Hardcoded color values are bad because theme changes cannot be uniformly applied.Instead use the theme specific colors such as `?android:attr/textColorPrimary` in attributes.&#xA;This ensures that a theme change from a light to a dark theme can be uniformlyapplied across the app."
+        errorLine1="    &lt;color name=&quot;switch_bar_state_disabled_color&quot;>#1FE3E3E3&lt;/color>"
+        errorLine2="    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
+        <location
+            file="res/values-night/colors.xml"
+            line="76"
+            column="5"/>
+    </issue>
+
     <issue
         id="HardCodedColor"
         severity="Error"
@@ -2957,6 +2973,22 @@
             column="5"/>
     </issue>
 
+    <issue
+        id="HardCodedColor"
+        severity="Error"
+        message="Avoid using hardcoded color"
+        category="Correctness"
+        priority="4"
+        summary="Using hardcoded color"
+        explanation="Hardcoded color values are bad because theme changes cannot be uniformly applied.Instead use the theme specific colors such as `?android:attr/textColorPrimary` in attributes.&#xA;This ensures that a theme change from a light to a dark theme can be uniformlyapplied across the app."
+        errorLine1="    &lt;color name=&quot;switch_bar_state_disabled_color&quot;>#1F1F1F1F&lt;/color>"
+        errorLine2="    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
+        <location
+            file="res/values/colors.xml"
+            line="219"
+            column="5"/>
+    </issue>
+
     <issue
         id="HardCodedColor"
         severity="Error"
@@ -6237,6 +6269,38 @@
             column="63"/>
     </issue>
 
+    <issue
+        id="HardCodedColor"
+        severity="Error"
+        message="Avoid using hardcoded color"
+        category="Correctness"
+        priority="4"
+        summary="Using hardcoded color"
+        explanation="Hardcoded color values are bad because theme changes cannot be uniformly applied.Instead use the theme specific colors such as `?android:attr/textColorPrimary` in attributes.&#xA;This ensures that a theme change from a light to a dark theme can be uniformlyapplied across the app."
+        errorLine1="            &lt;solid android:color=&quot;@color/switch_bar_state_disabled_color&quot;/>"
+        errorLine2="                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
+        <location
+            file="res/drawable/switch_bar_bg_disabled.xml"
+            line="22"
+            column="20"/>
+    </issue>
+
+    <issue
+        id="HardCodedColor"
+        severity="Error"
+        message="Avoid using hardcoded color"
+        category="Correctness"
+        priority="4"
+        summary="Using hardcoded color"
+        explanation="Hardcoded color values are bad because theme changes cannot be uniformly applied.Instead use the theme specific colors such as `?android:attr/textColorPrimary` in attributes.&#xA;This ensures that a theme change from a light to a dark theme can be uniformlyapplied across the app."
+        errorLine1="            &lt;solid android:color=&quot;@color/switch_bar_state_disabled_color&quot;/>"
+        errorLine2="                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
+        <location
+            file="res/drawable/switch_bar_bg_disabled.xml"
+            line="22"
+            column="20"/>
+    </issue>
+
     <issue
         id="HardCodedColor"
         severity="Error"

res/drawable/switch_bar_bg_disabled.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Copyright (C) 2023 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.
+  -->
+
+<ripple xmlns:android="http://schemas.android.com/apk/res/android"
+    android:color="?android:attr/colorControlHighlight">
+    <item>
+        <shape android:shape="rectangle">
+            <solid android:color="@color/switch_bar_state_disabled_color"/>
+            <corners android:radius="@dimen/settingslib_switch_bar_radius"/>
+        </shape>
+    </item>
+</ripple>

res/layout/flash_notification_preview_preference.xml

@@ -24,6 +24,7 @@
     android:background="@android:color/transparent">
 
     <FrameLayout
+        android:id="@+id/frame"
         android:layout_height="wrap_content"
         android:layout_width="match_parent"
         android:paddingStart="@dimen/settingslib_switchbar_padding_left"

res/values-night/colors.xml

@@ -71,5 +71,8 @@
     <!-- Flash notifications colors -->
     <!-- Screen flash notification color selected stroke in color selection dialog -->
     <color name="screen_flash_color_button_outer_circle_stroke_color">#FFFFFF</color>
+
+    <!-- Switch bar disabled state color-->
+    <color name="switch_bar_state_disabled_color">#1FE3E3E3</color>
 </resources>
 

res/values/colors.xml

@@ -214,4 +214,7 @@
     <color name="screen_flash_preset_opacity_color_10">#4DFF017E</color> <!-- 30% Rose -->
     <color name="screen_flash_preset_opacity_color_11">#4DFF00FE</color> <!-- 30% Magenta -->
     <color name="screen_flash_preset_opacity_color_12">#667F00FF</color> <!-- 40% Violet -->
+
+    <!-- Switch bar disabled state color-->
+    <color name="switch_bar_state_disabled_color">#1F1F1F1F</color>
 </resources>

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

@@ -17,16 +17,26 @@
 package com.android.settings.accessibility;
 
 import android.content.Context;
+import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
+import android.view.View;
+import android.widget.TextView;
 
+import androidx.annotation.ColorInt;
 import androidx.preference.Preference;
+import androidx.preference.PreferenceViewHolder;
 
 import com.android.settings.R;
+import com.android.settingslib.Utils;
 
 /**
  * Preference for Flash notifications preview.
  */
 public class FlashNotificationsPreviewPreference extends Preference {
+    private Drawable mBackgroundEnabled;
+    private Drawable mBackgroundDisabled;
+    @ColorInt
+    private int mTextColorDisabled;
 
     public FlashNotificationsPreviewPreference(Context context) {
         super(context);
@@ -52,5 +62,32 @@ public class FlashNotificationsPreviewPreference extends Preference {
 
     private void init() {
         setLayoutResource(R.layout.flash_notification_preview_preference);
+        mBackgroundEnabled = getContext().getDrawable(R.drawable.settingslib_switch_bar_bg_on);
+        mBackgroundDisabled = getContext().getDrawable(R.drawable.switch_bar_bg_disabled);
+        mTextColorDisabled = Utils.getColorAttrDefaultColor(getContext(),
+                android.R.attr.textColorPrimary);
+    }
+
+    @Override
+    public void onBindViewHolder(PreferenceViewHolder holder) {
+        super.onBindViewHolder(holder);
+
+        final boolean enabled = isEnabled();
+        final View frame = holder.findViewById(R.id.frame);
+        if (frame != null) {
+            frame.setBackground(enabled ? mBackgroundEnabled : mBackgroundDisabled);
+        }
+        final TextView title = (TextView) holder.findViewById(android.R.id.title);
+        if (title != null) {
+            @ColorInt final int textColorEnabled = title.getCurrentTextColor();
+            title.setAlpha(enabled ? 1f : 0.38f);
+            title.setTextColor(enabled ? textColorEnabled : mTextColorDisabled);
+        }
+    }
+
+    @Override
+    public void setEnabled(boolean enabled) {
+        super.setEnabled(enabled);
+        notifyChanged();
     }
 }

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

@@ -55,7 +55,7 @@ public class FlashNotificationsPreviewPreferenceController extends
             new Handler(Looper.getMainLooper())) {
         @Override
         public void onChange(boolean selfChange, @Nullable Uri uri) {
-            onSettingChanged();
+            updateState(mPreference);
         }
     };
 
@@ -73,7 +73,7 @@ public class FlashNotificationsPreviewPreferenceController extends
     public void displayPreference(PreferenceScreen screen) {
         super.displayPreference(screen);
         mPreference = screen.findPreference(getPreferenceKey());
-        onSettingChanged();
+        updateState(mPreference);
     }
 
     @Override
@@ -103,10 +103,13 @@ public class FlashNotificationsPreviewPreferenceController extends
         }
     }
 
-    private void onSettingChanged() {
+    @Override
-        if (mPreference == null) return;
+    public void updateState(Preference preference) {
-
+        super.updateState(preference);
-        mPreference.setEnabled(FlashNotificationsUtil.getFlashNotificationsState(mContext)
+        if (preference == null) {
+            return;
+        }
+        preference.setEnabled(FlashNotificationsUtil.getFlashNotificationsState(mContext)
                 != FlashNotificationsUtil.State.OFF);
     }
 }

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

@@ -19,20 +19,26 @@ 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.TextView;
 
+import androidx.annotation.ColorInt;
+import androidx.preference.PreferenceViewHolder;
 import androidx.test.core.app.ApplicationProvider;
 
 import com.android.settings.R;
+import com.android.settingslib.Utils;
 
+import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Spy;
 import org.mockito.junit.MockitoJUnit;
 import org.mockito.junit.MockitoRule;
-import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
+import org.robolectric.Shadows;
 
 @RunWith(RobolectricTestRunner.class)
 public class FlashNotificationsPreviewPreferenceTest {
@@ -41,37 +47,46 @@ public class FlashNotificationsPreviewPreferenceTest {
     public MockitoRule mMockitoRule = MockitoJUnit.rule();
     @Spy
     private final Context mContext = ApplicationProvider.getApplicationContext();
-    private final AttributeSet mAttributeSet = Robolectric.buildAttributeSet().build();
+    private FlashNotificationsPreviewPreference mFlashNotificationsPreviewPreference;
+    private PreferenceViewHolder mPreferenceViewHolder;
 
-    @Test
+    @Before
-    public void constructor_assertLayoutResource_P00() {
+    public void setUp() {
-        FlashNotificationsPreviewPreference preference = new FlashNotificationsPreviewPreference(
+        mPreferenceViewHolder = PreferenceViewHolder.createInstanceForTests(
-                mContext);
+                LayoutInflater.from(mContext).inflate(
-        assertThat(preference.getLayoutResource())
+                        R.layout.flash_notification_preview_preference, null));
-                .isEqualTo(R.layout.flash_notification_preview_preference);
+        mFlashNotificationsPreviewPreference = new FlashNotificationsPreviewPreference(mContext);
     }
 
     @Test
-    public void constructor_assertLayoutResource_P01() {
+    public void setEnabled_true_verifyEnabledUi() {
-        FlashNotificationsPreviewPreference preference = new FlashNotificationsPreviewPreference(
+        @ColorInt final int textColorEnabled = ((TextView) mPreferenceViewHolder.findViewById(
-                mContext, mAttributeSet);
+                android.R.id.title)).getCurrentTextColor();
-        assertThat(preference.getLayoutResource())
+
-                .isEqualTo(R.layout.flash_notification_preview_preference);
+        mFlashNotificationsPreviewPreference.setEnabled(true);
+        mFlashNotificationsPreviewPreference.onBindViewHolder(mPreferenceViewHolder);
+
+        final View frame = mPreferenceViewHolder.findViewById(R.id.frame);
+        final int backgroundResId = Shadows.shadowOf(frame.getBackground()).getCreatedFromResId();
+        assertThat(backgroundResId).isEqualTo(R.drawable.settingslib_switch_bar_bg_on);
+        final TextView title = (TextView) mPreferenceViewHolder.findViewById(android.R.id.title);
+        assertThat(title.getAlpha()).isEqualTo(1f);
+        assertThat(title.getCurrentTextColor()).isEqualTo(textColorEnabled);
     }
 
     @Test
-    public void constructor_assertLayoutResource_P02() {
+    public void setEnabled_false_verifyDisabledUi() {
-        FlashNotificationsPreviewPreference preference = new FlashNotificationsPreviewPreference(
+        @ColorInt final int textColorDisabled = Utils.getColorAttrDefaultColor(mContext,
-                mContext, mAttributeSet, 0);
+                android.R.attr.textColorPrimary);
-        assertThat(preference.getLayoutResource())
-                .isEqualTo(R.layout.flash_notification_preview_preference);
-    }
 
-    @Test
+        mFlashNotificationsPreviewPreference.setEnabled(false);
-    public void constructor_assertLayoutResource_P03() {
+        mFlashNotificationsPreviewPreference.onBindViewHolder(mPreferenceViewHolder);
-        FlashNotificationsPreviewPreference preference = new FlashNotificationsPreviewPreference(
+
-                mContext, mAttributeSet, 0, 0);
+        final View frame = mPreferenceViewHolder.findViewById(R.id.frame);
-        assertThat(preference.getLayoutResource())
+        final int backgroundResId = Shadows.shadowOf(frame.getBackground()).getCreatedFromResId();
-                .isEqualTo(R.layout.flash_notification_preview_preference);
+        assertThat(backgroundResId).isEqualTo(R.drawable.switch_bar_bg_disabled);
+        final TextView title = (TextView) mPreferenceViewHolder.findViewById(android.R.id.title);
+        assertThat(title.getAlpha()).isEqualTo(0.38f);
+        assertThat(title.getCurrentTextColor()).isEqualTo(textColorDisabled);
     }
 }