Merge "Add a preview image to the color mode preference."

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

@@ -16,10 +16,12 @@ package com.android.settings.display;
 import android.content.Context;
 import android.graphics.drawable.Drawable;
 import android.support.annotation.VisibleForTesting;
+import android.support.v7.preference.PreferenceScreen;
 
 import com.android.internal.app.ColorDisplayController;
 import com.android.internal.logging.nano.MetricsProto;
 
+import com.android.settings.applications.LayoutPreference;
 import com.android.settings.R;
 import com.android.settings.widget.RadioButtonPickerFragment;
 import com.android.settingslib.widget.CandidateInfo;
@@ -50,6 +52,19 @@ public class ColorModePreferenceFragment extends RadioButtonPickerFragment {
         return R.xml.color_mode_settings;
     }
 
+    @VisibleForTesting
+    void configureAndInstallPreview(LayoutPreference preview, PreferenceScreen screen) {
+        preview.setSelectable(false);
+        screen.addPreference(preview);
+    }
+
+    @Override
+    protected void addStaticPreferences(PreferenceScreen screen) {
+        final LayoutPreference preview = new LayoutPreference(screen.getContext(),
+                R.layout.color_mode_preview);
+        configureAndInstallPreview(preview, screen);
+    }
+
     @Override
     protected List<? extends CandidateInfo> getCandidates() {
         Context c = getContext();

src/com/android/settings/widget/RadioButtonPickerFragment.java

@@ -101,6 +101,13 @@ public abstract class RadioButtonPickerFragment extends InstrumentedPreferenceFr
         return false;
     }
 
+    /**
+     * Populate any static preferences, independent of the radio buttons.
+     * These might be used to provide extra information about the choices.
+     **/
+    protected void addStaticPreferences(PreferenceScreen screen) {
+    }
+
     protected CandidateInfo getCandidate(String key) {
         return mCandidates.get(key);
     }
@@ -134,6 +141,7 @@ public abstract class RadioButtonPickerFragment extends InstrumentedPreferenceFr
         final String systemDefaultKey = getSystemDefaultKey();
         final PreferenceScreen screen = getPreferenceScreen();
         screen.removeAll();
+        addStaticPreferences(screen);
 
         final int customLayoutResId = getRadioButtonPreferenceCustomLayoutResId();
         if (shouldShowItemNone()) {