1 files changed, 67 insertions, 0 deletions
diff --git a/library/main/src/com/android/setupwizardlib/items/AbstractItemHierarchy.java b/library/main/src/com/android/setupwizardlib/items/AbstractItemHierarchy.java
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index 0000000..c56e3bc
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+++ b/library/main/src/com/android/setupwizardlib/items/AbstractItemHierarchy.java
@@ -0,0 +1,67 @@
+/*
+ * 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.setupwizardlib.items;
+
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.util.AttributeSet;
+
+import com.android.setupwizardlib.R;
+
+import java.util.ArrayList;
+
+/**
+ * An abstract item hierarchy; provides default implementation for ID and observers.
+ */
+public abstract class AbstractItemHierarchy implements ItemHierarchy {
+
+    private ArrayList<Observer> mObservers = new ArrayList<>();
+    private int mId = 0;
+
+    public AbstractItemHierarchy() {
+    }
+
+    public AbstractItemHierarchy(Context context, AttributeSet attrs) {
+        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.SuwAbstractItem);
+        mId = a.getResourceId(R.styleable.SuwAbstractItem_android_id, 0);
+        a.recycle();
+    }
+
+    public void setId(int id) {
+        mId = id;
+    }
+
+    public int getId() {
+        return mId;
+    }
+
+    @Override
+    public void registerObserver(Observer observer) {
+        mObservers.add(observer);
+    }
+
+    @Override
+    public void unregisterObserver(Observer observer) {
+        mObservers.remove(observer);
+    }
+
+    public void notifyChanged() {
+        for (Observer observer : mObservers) {
+            observer.onChanged(this);
+        }
+    }
+}