Make sure vibration previews in Settings apply latest intensities

Update the Settings app to enforce fresh settings are applied to preview
vibrations triggered after the intensity is updated.

Add preview haptics to main switch, only when touch feedback is enabled,
and to the "apply ramping ringer" toggle for consistency with the rest
of the screen, using ringtone intensity for preview.

Bug: 219693646
Bug: 219695212
Bug: 157533521
Test: manual
Change-Id: I872a75d6b00dffae943b0f403185a39047909884

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

@@ -73,11 +73,11 @@ public abstract class VibrationIntensityPreferenceController extends SliderPrefe
         mSettingsContentObserver.onDisplayPreference(this, preference);
         preference.setEnabled(mPreferenceConfig.isPreferenceEnabled());
         preference.setSummaryProvider(unused -> mPreferenceConfig.getSummary());
-        // TODO: remove setContinuousUpdates and replace with a different way to play the haptic
-        // preview without relying on the setting being propagated to the service.
-        preference.setContinuousUpdates(true);
         preference.setMin(getMin());
         preference.setMax(getMax());
+        // Haptics previews played by the Settings app don't bypass user settings to be played.
+        // The sliders continuously updates the intensity value so the previews can apply them.
+        preference.setContinuousUpdates(true);
     }
 
     @Override

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

@@ -23,6 +23,8 @@ import android.content.Context;
 import android.database.ContentObserver;
 import android.net.Uri;
 import android.os.Handler;
+import android.os.VibrationAttributes;
+import android.os.Vibrator;
 import android.provider.Settings;
 
 import com.android.settings.R;
@@ -42,9 +44,11 @@ public class VibrationMainSwitchPreferenceController extends SettingsMainSwitchP
         implements LifecycleObserver, OnStart, OnStop {
 
     private final ContentObserver mSettingObserver;
+    private final Vibrator mVibrator;
 
     public VibrationMainSwitchPreferenceController(Context context, String preferenceKey) {
         super(context, preferenceKey);
+        mVibrator = context.getSystemService(Vibrator.class);
         mSettingObserver = new ContentObserver(new Handler(/* async= */ true)) {
             @Override
             public void onChange(boolean selfChange, Uri uri) {
@@ -79,9 +83,17 @@ public class VibrationMainSwitchPreferenceController extends SettingsMainSwitchP
 
     @Override
     public boolean setChecked(boolean isChecked) {
-        return Settings.System.putInt(mContext.getContentResolver(),
+        boolean success = Settings.System.putInt(mContext.getContentResolver(),
                 VibrationPreferenceConfig.MAIN_SWITCH_SETTING_KEY,
                 isChecked ? ON : OFF);
+
+        if (success && isChecked) {
+            // Play a haptic as preview for the main toggle only when touch feedback is enabled.
+            VibrationPreferenceConfig.playVibrationPreview(
+                    mVibrator, VibrationAttributes.USAGE_TOUCH);
+        }
+
+        return success;
     }
 
     @Override

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

@@ -49,6 +49,8 @@ public abstract class VibrationPreferenceConfig {
      * all device vibrations.
      */
     public static final String MAIN_SWITCH_SETTING_KEY = Settings.System.VIBRATE_ON;
+    private static final VibrationEffect PREVIEW_VIBRATION_EFFECT =
+            VibrationEffect.createPredefined(VibrationEffect.EFFECT_CLICK);
 
     protected final ContentResolver mContentResolver;
     private final AudioManager mAudioManager;
@@ -56,14 +58,22 @@ public abstract class VibrationPreferenceConfig {
     private final String mSettingKey;
     private final String mRingerModeSilentSummary;
     private final int mDefaultIntensity;
-    private final VibrationAttributes mVibrationAttributes;
+    private final VibrationAttributes mPreviewVibrationAttributes;
 
     /** Returns true if the user setting for enabling device vibrations is enabled. */
     public static boolean isMainVibrationSwitchEnabled(ContentResolver contentResolver) {
         return Settings.System.getInt(contentResolver, MAIN_SWITCH_SETTING_KEY, ON) == ON;
     }
 
-    public VibrationPreferenceConfig(Context context, String settingKey, int vibrationUsage) {
+    /** Play a vibration effect with intensity just selected by the user. */
+    public static void playVibrationPreview(Vibrator vibrator,
+            @VibrationAttributes.Usage int vibrationUsage) {
+        vibrator.vibrate(PREVIEW_VIBRATION_EFFECT,
+                createPreviewVibrationAttributes(vibrationUsage));
+    }
+
+    public VibrationPreferenceConfig(Context context, String settingKey,
+            @VibrationAttributes.Usage int vibrationUsage) {
         mContentResolver = context.getContentResolver();
         mVibrator = context.getSystemService(Vibrator.class);
         mAudioManager = context.getSystemService(AudioManager.class);
@@ -71,9 +81,7 @@ public abstract class VibrationPreferenceConfig {
                 R.string.accessibility_vibration_setting_disabled_for_silent_mode_summary);
         mSettingKey = settingKey;
         mDefaultIntensity = mVibrator.getDefaultVibrationIntensity(vibrationUsage);
-        mVibrationAttributes = new VibrationAttributes.Builder()
-                .setUsage(vibrationUsage)
-                .build();
+        mPreviewVibrationAttributes = createPreviewVibrationAttributes(vibrationUsage);
     }
 
     /** Returns the setting key for this setting preference. */
@@ -118,8 +126,7 @@ public abstract class VibrationPreferenceConfig {
 
     /** Play a vibration effect with intensity just selected by the user. */
     public void playVibrationPreview() {
-        mVibrator.vibrate(VibrationEffect.createPredefined(VibrationEffect.EFFECT_CLICK),
-                mVibrationAttributes);
+        mVibrator.vibrate(PREVIEW_VIBRATION_EFFECT, mPreviewVibrationAttributes);
     }
 
     private boolean isRingerModeSilent() {
@@ -128,6 +135,16 @@ public abstract class VibrationPreferenceConfig {
         return mAudioManager.getRingerModeInternal() == AudioManager.RINGER_MODE_SILENT;
     }
 
+    private static VibrationAttributes createPreviewVibrationAttributes(
+            @VibrationAttributes.Usage int vibrationUsage) {
+        return new VibrationAttributes.Builder()
+                .setUsage(vibrationUsage)
+                // Enforce fresh settings to be applied for the preview vibration, as they
+                // are played immediately after the new user values are set.
+                .setFlags(VibrationAttributes.FLAG_INVALIDATE_SETTINGS_CACHE)
+                .build();
+    }
+
     /** {@link ContentObserver} for a setting described by a {@link VibrationPreferenceConfig}. */
     public static final class SettingObserver extends ContentObserver {
         private static final Uri MAIN_SWITCH_SETTING_URI =

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

@@ -124,6 +124,12 @@ public class VibrationRampingRingerTogglePreferenceController
         if (isRingVibrationEnabled()) {
             // Don't update ramping ringer setting value if ring vibration is disabled.
             mAudioManager.setRampingRingerEnabled(isChecked);
+
+            if (isChecked) {
+                // Vibrate when toggle is enabled for consistency with all the other toggle/slides
+                // in the same screen.
+                mRingVibrationPreferenceConfig.playVibrationPreview();
+            }
         }
         return true;
     }