Merge "Fix dark theme and battery saver interaction" into qt-dev

src/com/android/settings/display/DarkUIPreferenceController.java

@@ -17,27 +17,53 @@
 package com.android.settings.display;
 
 import android.app.UiModeManager;
+import android.content.BroadcastReceiver;
 import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.PowerManager;
 import android.provider.Settings;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.fragment.app.Fragment;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
+import androidx.preference.SwitchPreference;
 
+import com.android.settings.R;
 import com.android.settings.core.TogglePreferenceController;
+import com.android.settingslib.core.lifecycle.LifecycleObserver;
+import com.android.settingslib.core.lifecycle.events.OnStart;
+import com.android.settingslib.core.lifecycle.events.OnStop;
 
-public class DarkUIPreferenceController extends TogglePreferenceController {
+public class DarkUIPreferenceController extends TogglePreferenceController implements
+        LifecycleObserver, OnStart, OnStop {
 
     public static final String DARK_MODE_PREFS = "dark_mode_prefs";
     public static final String PREF_DARK_MODE_DIALOG_SEEN = "dark_mode_dialog_seen";
     public static final int DIALOG_SEEN = 1;
+
+    @VisibleForTesting
+    SwitchPreference mPreference;
+
     private UiModeManager mUiModeManager;
+    private PowerManager mPowerManager;
     private Context mContext;
+
     private Fragment mFragment;
 
+    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            updateEnabledStateIfNeeded();
+        }
+    };
+
     public DarkUIPreferenceController(Context context, String key) {
         super(context, key);
         mContext = context;
         mUiModeManager = context.getSystemService(UiModeManager.class);
+        mPowerManager = context.getSystemService(PowerManager.class);
     }
 
     @Override
@@ -45,6 +71,18 @@ public class DarkUIPreferenceController extends TogglePreferenceController {
         return mUiModeManager.getNightMode() == UiModeManager.MODE_NIGHT_YES;
     }
 
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        mPreference = screen.findPreference(getPreferenceKey());
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        super.updateState(preference);
+        updateEnabledStateIfNeeded();
+    }
+
     @Override
     public boolean setChecked(boolean isChecked) {
         final boolean dialogSeen =
@@ -67,6 +105,29 @@ public class DarkUIPreferenceController extends TogglePreferenceController {
         }
     }
 
+    @VisibleForTesting
+    void updateEnabledStateIfNeeded() {
+        if (mPreference == null) {
+            return;
+        }
+        boolean isBatterySaver = isPowerSaveMode();
+        mPreference.setEnabled(!isBatterySaver);
+        if (isBatterySaver) {
+            int stringId = mUiModeManager.getNightMode() == UiModeManager.MODE_NIGHT_YES
+                    ? R.string.dark_ui_mode_disabled_summary_dark_theme_on
+                    : R.string.dark_ui_mode_disabled_summary_dark_theme_off;
+            mPreference.setSummary(mContext.getString(stringId));
+        } else {
+            mPreference.setSummary(null);
+        }
+    }
+
+    @VisibleForTesting
+    boolean isPowerSaveMode() {
+        return mPowerManager.isPowerSaveMode();
+    }
+
+
     @VisibleForTesting
     void setUiModeManager(UiModeManager uiModeManager) {
         mUiModeManager = uiModeManager;
@@ -76,6 +137,17 @@ public class DarkUIPreferenceController extends TogglePreferenceController {
         mFragment = fragment;
     }
 
+    @Override
+    public void onStart() {
+        mContext.registerReceiver(mReceiver,
+                new IntentFilter(PowerManager.ACTION_POWER_SAVE_MODE_CHANGED));
+    }
+
+    @Override
+    public void onStop() {
+        mContext.unregisterReceiver(mReceiver);
+    }
+
     @Override
     public int getAvailabilityStatus() {
         return AVAILABLE;