Load bookmarks asynchronously

 Bug: 5297900

Change-Id: I8b728cfe06799099e21c402d5da7087507209ffa

1 files changed, 193 insertions, 0 deletions

diff --git a/src/com/android/browser/util/ThreadedCursorAdapter.java b/src/com/android/browser/util/ThreadedCursorAdapter.java
new file mode 100644
index 00000000..fe59ad1c
--- /dev/null
+++ b/src/com/android/browser/util/ThreadedCursorAdapter.java
@@ -0,0 +1,193 @@
+/*
+ * Copyright (C) 2011 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.browser.util;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Message;
+import android.os.Process;
+import android.util.Log;
+import android.util.SparseArray;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Adapter;
+import android.widget.BaseAdapter;
+import android.widget.CursorAdapter;
+
+import com.android.browser.R;
+
+import java.lang.ref.WeakReference;
+import java.util.HashMap;
+
+public abstract class ThreadedCursorAdapter<T> extends BaseAdapter {
+
+    private static final String LOGTAG = "tca";
+    private static final boolean DEBUG = false;
+
+    private Context mContext;
+    private Object mCursorLock = new Object();
+    private CursorAdapter mCursorAdapter;
+    private T mLoadingObject;
+    private Handler mLoadHandler;
+    private Handler mHandler;
+    private int mSize;
+
+    private class LoadContainer {
+        WeakReference<View> view;
+        int position;
+        T bind_object;
+        Adapter owner;
+        boolean loaded;
+    }
+
+    public ThreadedCursorAdapter(Context context, Cursor c) {
+        mContext = context;
+        mCursorAdapter = new CursorAdapter(context, c, 0) {
+
+            @Override
+            public View newView(Context context, Cursor cursor, ViewGroup parent) {
+                throw new IllegalStateException("not supported");
+            }
+
+            @Override
+            public void bindView(View view, Context context, Cursor cursor) {
+                throw new IllegalStateException("not supported");
+            }
+
+            @Override
+            public void notifyDataSetChanged() {
+                super.notifyDataSetChanged();
+                mSize = getCount();
+                ThreadedCursorAdapter.this.notifyDataSetChanged();
+            }
+
+            @Override
+            public void notifyDataSetInvalidated() {
+                super.notifyDataSetInvalidated();
+                mSize = getCount();
+                ThreadedCursorAdapter.this.notifyDataSetInvalidated();
+            }
+
+        };
+        mSize = mCursorAdapter.getCount();
+        HandlerThread thread = new HandlerThread("threaded_adapter_" + this,
+                Process.THREAD_PRIORITY_BACKGROUND);
+        thread.start();
+        mLoadHandler = new Handler(thread.getLooper()) {
+            @SuppressWarnings("unchecked")
+            @Override
+            public void handleMessage(Message msg) {
+                if (DEBUG) {
+                    Log.d(LOGTAG, "loading: " + msg.what);
+                }
+                loadRowObject(msg.what, (LoadContainer) msg.obj);
+            }
+        };
+        mHandler = new Handler() {
+            @Override
+            public void handleMessage(Message msg) {
+                @SuppressWarnings("unchecked")
+                LoadContainer container = (LoadContainer) msg.obj;
+                if (container == null) {
+                    return;
+                }
+                View view = container.view.get();
+                if (view == null
+                        || container.owner != ThreadedCursorAdapter.this
+                        || container.position != msg.what) {
+                    return;
+                }
+                container.loaded = true;
+                bindView(view, container.bind_object);
+            }
+        };
+    }
+
+    @Override
+    public int getCount() {
+        return mSize;
+    }
+
+    @Override
+    public Cursor getItem(int position) {
+        return (Cursor) mCursorAdapter.getItem(position);
+    }
+
+    @Override
+    public long getItemId(int position) {
+        return position;
+    }
+
+    private void loadRowObject(int position, LoadContainer container) {
+        if (container == null
+                || container.position != position
+                || container.owner != ThreadedCursorAdapter.this
+                || container.view.get() == null) {
+            return;
+        }
+        synchronized (mCursorLock) {
+            Cursor c = (Cursor) mCursorAdapter.getItem(position);
+            container.bind_object = getRowObject(c, container.bind_object);
+        }
+        mHandler.obtainMessage(position, container).sendToTarget();
+    }
+
+    @Override
+    public View getView(int position, View convertView, ViewGroup parent) {
+        if (convertView == null) {
+            convertView = newView(mContext, parent);
+        }
+        @SuppressWarnings("unchecked")
+        LoadContainer container = (LoadContainer) convertView.getTag(R.id.load_object);
+        if (container == null) {
+            container = new LoadContainer();
+            container.view = new WeakReference<View>(convertView);
+            convertView.setTag(R.id.load_object, container);
+        }
+        if (container.position == position
+                && container.owner == this
+                && container.loaded) {
+            bindView(convertView, container.bind_object);
+        } else {
+            bindView(convertView, cachedLoadObject());
+            container.position = position;
+            container.loaded = false;
+            container.owner = this;
+            mLoadHandler.obtainMessage(position, container).sendToTarget();
+        }
+        return convertView;
+    }
+
+    private T cachedLoadObject() {
+        if (mLoadingObject == null) {
+            mLoadingObject = getLoadingObject();
+        }
+        return mLoadingObject;
+    }
+
+    public void changeCursor(Cursor cursor) {
+        synchronized (mCursorLock) {
+            mCursorAdapter.changeCursor(cursor);
+        }
+    }
+
+    public abstract View newView(Context context, ViewGroup parent);
+    public abstract void bindView(View view, T object);
+    public abstract T getRowObject(Cursor c, T recycleObject);
+    public abstract T getLoadingObject();
+}
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