Allow users to set notification topic importance.

In the absence of mocks, the silder is shown in the
'normal' position if the user hasn't yet
chosen an importance value.

Bug: 22854014
Change-Id: I51594959412775fe89b29af66ddcb13bafa67255

src/com/android/settings/notification/ImportanceSeekBarPreference.java

@@ -0,0 +1,118 @@
+/**
+ * Copyright (C) 2015 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.notification;
+
+import com.android.settings.R;
+import com.android.settings.SeekBarPreference;
+
+import android.content.Context;
+import android.service.notification.NotificationListenerService;
+import android.support.v7.preference.PreferenceViewHolder;
+import android.util.AttributeSet;
+import android.widget.SeekBar;
+import android.widget.TextView;
+
+/**
+ * A slider preference that controls notification importance.
+ **/
+public class ImportanceSeekBarPreference extends SeekBarPreference implements
+        SeekBar.OnSeekBarChangeListener {
+    private static final String TAG = "ImportanceSeekBarPref";
+
+    public static final int IMPORTANCE_PROGRESS_OFFSET = 2;
+    private Callback mCallback;
+    private TextView mSummaryTextView;
+    private String mSummary;
+
+    public ImportanceSeekBarPreference(Context context, AttributeSet attrs, int defStyleAttr,
+            int defStyleRes) {
+        super(context, attrs, defStyleAttr, defStyleRes);
+        setLayoutResource(R.layout.preference_importance_slider);
+    }
+
+    public ImportanceSeekBarPreference(Context context, AttributeSet attrs, int defStyleAttr) {
+        this(context, attrs, defStyleAttr, 0);
+    }
+
+    public ImportanceSeekBarPreference(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public ImportanceSeekBarPreference(Context context) {
+        this(context, null);
+    }
+
+    public void setCallback(Callback callback) {
+        mCallback = callback;
+    }
+
+    @Override
+    public void onBindViewHolder(PreferenceViewHolder view) {
+        super.onBindViewHolder(view);
+        mSummaryTextView = (TextView) view.findViewById(com.android.internal.R.id.summary);
+    }
+
+    @Override
+    public void setProgress(int progress) {
+        mSummary = getProgressSummary(progress);
+        super.setProgress(progress);
+    }
+
+    @Override
+    public void onProgressChanged(SeekBar seekBar, final int progress, boolean fromTouch) {
+        super.onProgressChanged(seekBar, progress, fromTouch);
+        if (mSummaryTextView != null) {
+            mSummaryTextView.setText(getProgressSummary(progress));
+        }
+        if (fromTouch) {
+            mCallback.onImportanceChanged(progress);
+        }
+    }
+
+    @Override
+    public CharSequence getSummary() {
+        return mSummary;
+    }
+
+    private String getProgressSummary(int progress) {
+        // Map progress 0-4 values to Importance's -2-2.
+        progress = progress - IMPORTANCE_PROGRESS_OFFSET;
+        switch (progress) {
+            case NotificationListenerService.Ranking.IMPORTANCE_NONE:
+                return getContext().getString(
+                        com.android.internal.R.string.notification_importance_blocked);
+            case NotificationListenerService.Ranking.IMPORTANCE_LOW:
+                return getContext().getString(
+                        com.android.internal.R.string.notification_importance_low);
+            case NotificationListenerService.Ranking.IMPORTANCE_DEFAULT:
+                return getContext().getString(
+                        com.android.internal.R.string.notification_importance_default);
+            case NotificationListenerService.Ranking.IMPORTANCE_HIGH:
+                return getContext().getString(
+                        com.android.internal.R.string.notification_importance_high);
+            case NotificationListenerService.Ranking.IMPORTANCE_MAX:
+                return getContext().getString(
+                        com.android.internal.R.string.notification_importance_max);
+            default:
+                return "";
+        }
+    }
+
+    public interface Callback {
+        void onImportanceChanged(int progress);
+    }
+}