src/com/android/apps/tag/MyTagList.java - platform/packages/apps/Tag - Gitiles

 /*
  * Copyright (C) 2010 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.apps.tag;

 import com.android.apps.tag.provider.TagContract.NdefMessages;
 import com.android.apps.tag.record.RecordEditInfo;
 import com.android.apps.tag.record.TextRecord;
 import com.android.apps.tag.record.UriRecord;
 import com.android.apps.tag.record.VCardRecord;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Lists;

 import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.ContentUris;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.DialogInterface.OnClickListener;
 import android.content.Intent;
 import android.database.CharArrayBuffer;
 import android.database.Cursor;
 import android.net.Uri;
 import android.nfc.FormatException;
 import android.nfc.NdefMessage;
 import android.nfc.NfcAdapter;
 import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.ContextMenu;
 import android.view.ContextMenu.ContextMenuInfo;
 import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.AdapterView;
 import android.widget.AdapterView.AdapterContextMenuInfo;
 import android.widget.AdapterView.OnItemClickListener;
 import android.widget.CheckBox;
 import android.widget.CursorAdapter;
 import android.widget.ImageView;
 import android.widget.ListView;
 import android.widget.SimpleAdapter;
 import android.widget.TextView;
 import android.widget.Toast;

 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Set;

 /**
  * Displays the list of tags that can be set as "My tag", and allows the user to select the
  * active tag that the device shares.
  */
 public class MyTagList
         extends Activity
         implements OnItemClickListener, View.OnClickListener,
                    TagService.SaveCallbacks,
                    DialogInterface.OnClickListener {

     static final String TAG = "TagList";

     private static final int REQUEST_EDIT = 0;
     private static final int DIALOG_ID_SELECT_ACTIVE_TAG = 0;
     private static final int DIALOG_ID_ADD_NEW_TAG = 1;

     private static final String BUNDLE_KEY_TAG_ID_IN_EDIT = "tag-edit";
     private static final String PREF_KEY_ACTIVE_TAG = "active-my-tag";
     static final String PREF_KEY_TAG_TO_WRITE = "tag-to-write";

     static final String[] SUPPORTED_TYPES = new String[] {
             VCardRecord.RECORD_TYPE,
             UriRecord.RECORD_TYPE,
             TextRecord.RECORD_TYPE,
     };

     private View mSelectActiveTagAnchor;
     private View mActiveTagDetails;
     private CheckBox mEnabled;
     private ListView mList;

     private TagAdapter mAdapter;
     private long mActiveTagId;
     private Uri mTagBeingSaved;
     private NdefMessage mActiveTag;

     private WeakReference<SelectActiveTagDialog> mSelectActiveTagDialog;
     private long mTagIdInEdit = -1;
     private long mTagIdLongPressed;

     private boolean mWriteSupport = false;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         setContentView(R.layout.my_tag_activity);

         if (savedInstanceState != null) {
             mTagIdInEdit = savedInstanceState.getLong(BUNDLE_KEY_TAG_ID_IN_EDIT, -1);
         }

         // Set up the check box to toggle My tag sharing.
         mEnabled = (CheckBox) findViewById(R.id.toggle_enabled_checkbox);
         mEnabled.setChecked(false);  // Set after initial data load completes.
         findViewById(R.id.toggle_enabled_target).setOnClickListener(this);

         // Setup the active tag selector.
         mActiveTagDetails = findViewById(R.id.active_tag_details);
         mSelectActiveTagAnchor = findViewById(R.id.choose_my_tag);
         findViewById(R.id.active_tag).setOnClickListener(this);
         updateActiveTagView(null);  // Filled in after initial data load.

         mActiveTagId = getPreferences(Context.MODE_PRIVATE).getLong(PREF_KEY_ACTIVE_TAG, -1);

         // Setup the list.
         mAdapter = new TagAdapter(this);
         mList = (ListView) findViewById(android.R.id.list);
         mList.setAdapter(mAdapter);
         mList.setOnItemClickListener(this);
         findViewById(R.id.add_tag).setOnClickListener(this);

         // Don't setup the empty view until after the first load
         // so the empty text doesn't flash when first loading the
         // activity.
         mList.setEmptyView(null);

         // Kick off an async task to load the tags.
         new TagLoaderTask().execute((Void[]) null);

         // If we're not on a user build offer a back door for writing tags.
         // The UX is horrible so we don't want to ship it but need it for testing.
         if (!Build.TYPE.equalsIgnoreCase("user")) {
             mWriteSupport = true;
         }
         registerForContextMenu(mList);

         if (getIntent().hasExtra(EditTagActivity.EXTRA_RESULT_MSG)) {
             NdefMessage msg = (NdefMessage) Preconditions.checkNotNull(
                     getIntent().getParcelableExtra(EditTagActivity.EXTRA_RESULT_MSG));
             saveNewMessage(msg);
         }
     }

     @Override
     protected void onRestart() {
         super.onRestart();
         mTagIdInEdit = -1;
     }

     @Override
     protected void onSaveInstanceState(Bundle outState) {
         super.onSaveInstanceState(outState);
         outState.putLong(BUNDLE_KEY_TAG_ID_IN_EDIT, mTagIdInEdit);
     }

     @Override
     protected void onDestroy() {
         if (mAdapter != null) {
             mAdapter.changeCursor(null);
         }
         super.onDestroy();
     }

     @Override
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
         editTag(id);
     }

     /**
      * Opens the tag editor for a particular tag.
      */
     private void editTag(long id) {
         // TODO: use implicit Intent?
         Intent intent = new Intent(this, EditTagActivity.class);
         intent.setData(ContentUris.withAppendedId(NdefMessages.CONTENT_URI, id));
         mTagIdInEdit = id;
         startActivityForResult(intent, REQUEST_EDIT);
     }

     public void setEmptyView() {
         // TODO: set empty view.
     }

     public interface TagQuery {
         static final String[] PROJECTION = new String[] {
                 NdefMessages._ID, // 0
                 NdefMessages.DATE, // 1
                 NdefMessages.TITLE, // 2
                 NdefMessages.BYTES, // 3
         };

         static final int COLUMN_ID = 0;
         static final int COLUMN_DATE = 1;
         static final int COLUMN_TITLE = 2;
         static final int COLUMN_BYTES = 3;
     }

     /**
      * Asynchronously loads the tags info from the database.
      */
     final class TagLoaderTask extends AsyncTask<Void, Void, Cursor> {
         @Override
         public Cursor doInBackground(Void... args) {
             Cursor cursor = getContentResolver().query(
                     NdefMessages.CONTENT_URI,
                     TagQuery.PROJECTION,
                     NdefMessages.IS_MY_TAG + "=1",
                     null, NdefMessages.DATE + " DESC");

             // Ensure the cursor executes and fills its window
             if (cursor != null) cursor.getCount();
             return cursor;
         }

         @Override
         protected void onPostExecute(Cursor cursor) {
             mAdapter.changeCursor(cursor);

             if (cursor == null || cursor.getCount() == 0) {
                 setEmptyView();
             } else {
                 // Find the active tag.
                 if (mTagBeingSaved != null) {
                     selectTagBeingSaved(mTagBeingSaved);

                 } else if (mActiveTagId != -1) {
                     cursor.moveToPosition(-1);
                     while (cursor.moveToNext()) {
                         if (mActiveTagId == cursor.getLong(TagQuery.COLUMN_ID)) {
                             selectActiveTag(cursor.getPosition());
                             break;
                         }
                     }
                 }
             }


             SelectActiveTagDialog dialog = (mSelectActiveTagDialog == null)
                     ? null : mSelectActiveTagDialog.get();
             if (dialog != null) {
                 dialog.setData(cursor);
             }
         }
     }

     /**
      * Struct to hold pointers to views in the list items to save time at view binding time.
      */
     static final class ViewHolder {
         public CharArrayBuffer titleBuffer;
         public TextView mainLine;
         public ImageView activeIcon;
     }

     /**
      * Adapter to display the the My tag entries.
      */
     public class TagAdapter extends CursorAdapter {
         private final LayoutInflater mInflater;

         public TagAdapter(Context context) {
             super(context, null, false);
             mInflater = LayoutInflater.from(context);
         }

         @Override
         public void bindView(View view, Context context, Cursor cursor) {
             ViewHolder holder = (ViewHolder) view.getTag();

             CharArrayBuffer buf = holder.titleBuffer;
             cursor.copyStringToBuffer(TagQuery.COLUMN_TITLE, buf);
             holder.mainLine.setText(buf.data, 0, buf.sizeCopied);

             boolean isActive = cursor.getLong(TagQuery.COLUMN_ID) == mActiveTagId;
             holder.activeIcon.setVisibility(isActive ? View.VISIBLE : View.GONE);
         }

         @Override
         public View newView(Context context, Cursor cursor, ViewGroup parent) {
             View view = mInflater.inflate(R.layout.tag_list_item, null);

             // Cache items for the view
             ViewHolder holder = new ViewHolder();
             holder.titleBuffer = new CharArrayBuffer(64);
             holder.mainLine = (TextView) view.findViewById(R.id.title);
             holder.activeIcon = (ImageView) view.findViewById(R.id.active_tag_icon);
             view.findViewById(R.id.date).setVisibility(View.GONE);
             view.setTag(holder);

             return view;
         }

         @Override
         public void onContentChanged() {
             // Kick off an async query to refresh the list
             new TagLoaderTask().execute((Void[]) null);
         }
     }

     @Override
     public void onClick(View target) {
         switch (target.getId()) {
             case R.id.toggle_enabled_target:
                 boolean enabled = !mEnabled.isChecked();
                 if (enabled) {
                     if (mActiveTag != null) {
                         enableSharingAndStoreTag();
                         return;
                     }
                     Toast.makeText(
                             this,
                             getResources().getString(R.string.no_tag_selected),
                             Toast.LENGTH_SHORT).show();
                 }

                 disableSharing();
                 break;

             case R.id.add_tag:
                 showDialog(DIALOG_ID_ADD_NEW_TAG);
                 break;

             case R.id.active_tag:
                 if (mAdapter.getCursor() == null || mAdapter.getCursor().isClosed()) {
                     // Hopefully shouldn't happen.
                     return;
                 }

                 if (mAdapter.getCursor().getCount() == 0) {
                     OnClickListener onAdd = new OnClickListener() {
                         @Override
                         public void onClick(DialogInterface dialog, int which) {
                             if (which == AlertDialog.BUTTON_POSITIVE) {
                                 showDialog(DIALOG_ID_ADD_NEW_TAG);
                             }
                         }
                     };
                     new AlertDialog.Builder(this)
                             .setNegativeButton(android.R.string.cancel, null)
                             .setPositiveButton(R.string.add_tag, onAdd)
                             .setMessage(R.string.no_tags_created)
                             .show();
                     return;
                 }
                 showDialog(DIALOG_ID_SELECT_ACTIVE_TAG);
                 break;
         }
     }

     @Override
     public void onCreateContextMenu(ContextMenu menu, View view, ContextMenuInfo info) {
         Cursor cursor = mAdapter.getCursor();
         if (cursor == null
                 || cursor.isClosed()
                 || !cursor.moveToPosition(((AdapterContextMenuInfo) info).position)) {
             return;
         }

         menu.setHeaderTitle(cursor.getString(TagQuery.COLUMN_TITLE));
         long id = cursor.getLong(TagQuery.COLUMN_ID);
         MenuInflater inflater = getMenuInflater();
         inflater.inflate(R.menu.my_tag_list_context_menu, menu);

         // Prepare the menu for the item.
         menu.findItem(R.id.set_as_active).setVisible(id != mActiveTagId);
         mTagIdLongPressed = id;

         if (mWriteSupport) {
             menu.add(0, 1, 0, "Write to tag");
         }
     }

     @Override
     public boolean onContextItemSelected(MenuItem item) {
         long id = mTagIdLongPressed;
         switch (item.getItemId()) {
             case R.id.delete:
                 deleteTag(id);
                 return true;

             case R.id.set_as_active:
                 Cursor cursor = mAdapter.getCursor();
                 if (cursor == null || cursor.isClosed()) {
                     break;
                 }

                 for (int position = 0; cursor.moveToPosition(position); position++) {
                     if (cursor.getLong(TagQuery.COLUMN_ID) == id) {
                         selectActiveTag(position);
                         return true;
                     }
                 }
                 break;

             case R.id.edit:
                 editTag(id);
                 return true;

             case 1:
                 AdapterView.AdapterContextMenuInfo info;
                 try {
                     info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
                 } catch (ClassCastException e) {
                     Log.e(TAG, "bad menuInfo", e);
                     break;
                 }

                 Intent intent = new Intent(this, WriteTagActivity.class);
                 intent.putExtra("id", info.id);
                 startActivity(intent);
                 return true;
         }
         return false;
     }

     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         if (requestCode == REQUEST_EDIT && resultCode == RESULT_OK) {
             NdefMessage msg = (NdefMessage) Preconditions.checkNotNull(
                     data.getParcelableExtra(EditTagActivity.EXTRA_RESULT_MSG));

             if (mTagIdInEdit != -1) {
                 TagService.updateMyMessage(this, mTagIdInEdit, msg);
             } else {
                 saveNewMessage(msg);
             }
         }
     }

     private void saveNewMessage(NdefMessage msg) {
         TagService.saveMyMessage(this, msg, this);
     }

     @Override
     public void onSaveComplete(Uri newMsgUri) {
         if (isFinishing()) {
             // Callback came asynchronously and was after we finished - ignore.
             return;
         }
         mTagBeingSaved = newMsgUri;
         selectTagBeingSaved(newMsgUri);
     }

     @Override
     protected Dialog onCreateDialog(int id, Bundle args) {
         Context lightTheme = new ContextThemeWrapper(this, android.R.style.Theme_Light);
         if (id == DIALOG_ID_SELECT_ACTIVE_TAG) {
             SelectActiveTagDialog dialog = new SelectActiveTagDialog(lightTheme,
                     mAdapter.getCursor());
             dialog.setInverseBackgroundForced(true);
             mSelectActiveTagDialog = new WeakReference<SelectActiveTagDialog>(dialog);
             return dialog;
         } else if (id == DIALOG_ID_ADD_NEW_TAG) {
             ContentSelectorAdapter adapter = new ContentSelectorAdapter(lightTheme,
                     SUPPORTED_TYPES);
             AlertDialog dialog = new AlertDialog.Builder(lightTheme)
                     .setTitle(R.string.select_type)
                     .setIcon(0)
                     .setNegativeButton(android.R.string.cancel, this)
                     .setAdapter(adapter, this)
                     .create();
             adapter.setListView(dialog.getListView());
             dialog.setInverseBackgroundForced(true);
             return dialog;
         }
         return super.onCreateDialog(id, args);
     }

     @Override
     public void onClick(DialogInterface dialog, int which) {
         if (which == DialogInterface.BUTTON_NEGATIVE) {
             dialog.cancel();
         } else {
             RecordEditInfo info = (RecordEditInfo) ((AlertDialog) dialog).getListView()
                     .getAdapter().getItem(which);
             Intent intent = new Intent(this, EditTagActivity.class);
             intent.putExtra(EditTagActivity.EXTRA_NEW_RECORD_INFO, info);
             startActivityForResult(intent, REQUEST_EDIT);
         }
     }

     /**
      * Selects the tag to be used as the "My tag" shared tag.
      *
      * This does not necessarily persist the selection to the {@code NfcAdapter}. That must be done
      * via {@link #enableSharingAndStoreTag()}. However, it will call {@link #disableSharing()}
      * if the tag is invalid.
      */
     private void selectActiveTag(int position) {
         Cursor cursor = mAdapter.getCursor();
         if (cursor != null && cursor.moveToPosition(position)) {
             mActiveTagId = cursor.getLong(TagQuery.COLUMN_ID);

             try {
                 mActiveTag = new NdefMessage(cursor.getBlob(TagQuery.COLUMN_BYTES));

                 // Persist active tag info to preferences.
                 getPreferences(Context.MODE_PRIVATE)
                         .edit()
                         .putLong(PREF_KEY_ACTIVE_TAG, mActiveTagId)
                         .apply();

                 updateActiveTagView(cursor.getString(TagQuery.COLUMN_TITLE));
                 mAdapter.notifyDataSetChanged();

                 // If there was an existing shared tag, we update the contents, since
                 // the active tag contents may have been changed. This also forces the
                 // active tag to be in sync with what the NfcAdapter.
                 if (NfcAdapter.getDefaultAdapter(this).getLocalNdefMessage() != null) {
                     enableSharingAndStoreTag();
                 }

             } catch (FormatException e) {
                 // TODO: handle.
                 disableSharing();
             }
         } else {
             updateActiveTagView(null);
             disableSharing();
         }
         mTagBeingSaved = null;
     }

     /**
      * Selects the tag to be used as the "My tag" shared tag, if the specified URI is found.
      * If the URI is not found, the next load will attempt to look for a matching tag to select.
      *
      * Commonly used for new tags that was just added to the database, and may not yet be
      * reflected in the {@code Cursor}.
      */
     private void selectTagBeingSaved(Uri uri) {
         Cursor cursor = mAdapter.getCursor();
         if (cursor == null) {
             return;
         }
         cursor.moveToPosition(-1);
         while (cursor.moveToNext()) {
             Uri tagUri = ContentUris.withAppendedId(
                     NdefMessages.CONTENT_URI,
                     cursor.getLong(TagQuery.COLUMN_ID));
             if (tagUri.equals(uri)) {
                 selectActiveTag(cursor.getPosition());
                 return;
             }
         }
     }

     private void enableSharingAndStoreTag() {
         mEnabled.setChecked(true);
         NfcAdapter.getDefaultAdapter(this).setLocalNdefMessage(
                 Preconditions.checkNotNull(mActiveTag));
     }

     private void disableSharing() {
         mEnabled.setChecked(false);
         NfcAdapter.getDefaultAdapter(this).setLocalNdefMessage(null);
     }

     private void updateActiveTagView(String title) {
         if (title == null) {
             mActiveTagDetails.setVisibility(View.GONE);
             mSelectActiveTagAnchor.setVisibility(View.VISIBLE);
         } else {
             mActiveTagDetails.setVisibility(View.VISIBLE);
             ((TextView) mActiveTagDetails.findViewById(R.id.active_tag_title)).setText(title);
             mSelectActiveTagAnchor.setVisibility(View.GONE);
         }
     }

     /**
      * Removes the tag from the "My tag" list.
      */
     private void deleteTag(long id) {
         if (id == mActiveTagId) {
             selectActiveTag(-1);
         }
         TagService.delete(this, ContentUris.withAppendedId(NdefMessages.CONTENT_URI, id));
     }

     class SelectActiveTagDialog extends AlertDialog
             implements DialogInterface.OnClickListener, OnItemClickListener {

         private final ArrayList<HashMap<String, String>> mData;
         private final SimpleAdapter mSelectAdapter;

         protected SelectActiveTagDialog(Context context, Cursor cursor) {
             super(context);

             setTitle(context.getResources().getString(R.string.choose_my_tag));
             ListView list = new ListView(context);

             mData = Lists.newArrayList();
             mSelectAdapter = new SimpleAdapter(
                     context,
                     mData,
                     android.R.layout.simple_list_item_1,
                     new String[] { "title" },
                     new int[] { android.R.id.text1 });

             list.setAdapter(mSelectAdapter);
             list.setOnItemClickListener(this);
             setView(list);
             setIcon(0);
             setButton(
                     DialogInterface.BUTTON_POSITIVE,
                     context.getString(android.R.string.cancel),
                     this);

             setData(cursor);
         }

         public void setData(final Cursor cursor) {
             if ((cursor == null) || (cursor.getCount() == 0)) {
                 cancel();
                 return;
             }
             mData.clear();

             cursor.moveToPosition(-1);
             while (cursor.moveToNext()) {
                 mData.add(new HashMap<String, String>() {{
                     put("title", cursor.getString(MyTagList.TagQuery.COLUMN_TITLE));
                 }});
             }

             mSelectAdapter.notifyDataSetChanged();
         }

         @Override
         public void onClick(DialogInterface dialog, int which) {
             cancel();
         }

         @Override
         public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
             selectActiveTag(position);
             enableSharingAndStoreTag();
             cancel();
         }
     }
 }
	/*
	* Copyright (C) 2010 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.apps.tag;

	import com.android.apps.tag.provider.TagContract.NdefMessages;
	import com.android.apps.tag.record.RecordEditInfo;
	import com.android.apps.tag.record.TextRecord;
	import com.android.apps.tag.record.UriRecord;
	import com.android.apps.tag.record.VCardRecord;
	import com.google.common.base.Preconditions;
	import com.google.common.collect.ImmutableSet;
	import com.google.common.collect.Lists;

	import android.app.Activity;
	import android.app.AlertDialog;
	import android.app.Dialog;
	import android.content.ContentUris;
	import android.content.Context;
	import android.content.DialogInterface;
	import android.content.DialogInterface.OnClickListener;
	import android.content.Intent;
	import android.database.CharArrayBuffer;
	import android.database.Cursor;
	import android.net.Uri;
	import android.nfc.FormatException;
	import android.nfc.NdefMessage;
	import android.nfc.NfcAdapter;
	import android.os.AsyncTask;
	import android.os.Build;
	import android.os.Bundle;
	import android.util.Log;
	import android.view.ContextMenu;
	import android.view.ContextMenu.ContextMenuInfo;
	import android.view.ContextThemeWrapper;
	import android.view.LayoutInflater;
	import android.view.MenuInflater;
	import android.view.MenuItem;
	import android.view.View;
	import android.view.ViewGroup;
	import android.widget.AdapterView;
	import android.widget.AdapterView.AdapterContextMenuInfo;
	import android.widget.AdapterView.OnItemClickListener;
	import android.widget.CheckBox;
	import android.widget.CursorAdapter;
	import android.widget.ImageView;
	import android.widget.ListView;
	import android.widget.SimpleAdapter;
	import android.widget.TextView;
	import android.widget.Toast;

	import java.lang.ref.WeakReference;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.Set;

	/**
	* Displays the list of tags that can be set as "My tag", and allows the user to select the
	* active tag that the device shares.
	*/
	public class MyTagList
	extends Activity
	implements OnItemClickListener, View.OnClickListener,
	TagService.SaveCallbacks,
	DialogInterface.OnClickListener {

	static final String TAG = "TagList";

	private static final int REQUEST_EDIT = 0;
	private static final int DIALOG_ID_SELECT_ACTIVE_TAG = 0;
	private static final int DIALOG_ID_ADD_NEW_TAG = 1;

	private static final String BUNDLE_KEY_TAG_ID_IN_EDIT = "tag-edit";
	private static final String PREF_KEY_ACTIVE_TAG = "active-my-tag";
	static final String PREF_KEY_TAG_TO_WRITE = "tag-to-write";

	static final String[] SUPPORTED_TYPES = new String[] {
	VCardRecord.RECORD_TYPE,
	UriRecord.RECORD_TYPE,
	TextRecord.RECORD_TYPE,
	};

	private View mSelectActiveTagAnchor;
	private View mActiveTagDetails;
	private CheckBox mEnabled;
	private ListView mList;

	private TagAdapter mAdapter;
	private long mActiveTagId;
	private Uri mTagBeingSaved;
	private NdefMessage mActiveTag;

	private WeakReference<SelectActiveTagDialog> mSelectActiveTagDialog;
	private long mTagIdInEdit = -1;
	private long mTagIdLongPressed;

	private boolean mWriteSupport = false;

	@Override
	public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	setContentView(R.layout.my_tag_activity);

	if (savedInstanceState != null) {
	mTagIdInEdit = savedInstanceState.getLong(BUNDLE_KEY_TAG_ID_IN_EDIT, -1);
	}

	// Set up the check box to toggle My tag sharing.
	mEnabled = (CheckBox) findViewById(R.id.toggle_enabled_checkbox);
	mEnabled.setChecked(false); // Set after initial data load completes.
	findViewById(R.id.toggle_enabled_target).setOnClickListener(this);

	// Setup the active tag selector.
	mActiveTagDetails = findViewById(R.id.active_tag_details);
	mSelectActiveTagAnchor = findViewById(R.id.choose_my_tag);
	findViewById(R.id.active_tag).setOnClickListener(this);
	updateActiveTagView(null); // Filled in after initial data load.

	mActiveTagId = getPreferences(Context.MODE_PRIVATE).getLong(PREF_KEY_ACTIVE_TAG, -1);

	// Setup the list.
	mAdapter = new TagAdapter(this);
	mList = (ListView) findViewById(android.R.id.list);
	mList.setAdapter(mAdapter);
	mList.setOnItemClickListener(this);
	findViewById(R.id.add_tag).setOnClickListener(this);

	// Don't setup the empty view until after the first load
	// so the empty text doesn't flash when first loading the
	// activity.
	mList.setEmptyView(null);

	// Kick off an async task to load the tags.
	new TagLoaderTask().execute((Void[]) null);

	// If we're not on a user build offer a back door for writing tags.
	// The UX is horrible so we don't want to ship it but need it for testing.
	if (!Build.TYPE.equalsIgnoreCase("user")) {
	mWriteSupport = true;
	}
	registerForContextMenu(mList);

	if (getIntent().hasExtra(EditTagActivity.EXTRA_RESULT_MSG)) {
	NdefMessage msg = (NdefMessage) Preconditions.checkNotNull(
	getIntent().getParcelableExtra(EditTagActivity.EXTRA_RESULT_MSG));
	saveNewMessage(msg);
	}
	}

	@Override
	protected void onRestart() {
	super.onRestart();
	mTagIdInEdit = -1;
	}

	@Override
	protected void onSaveInstanceState(Bundle outState) {
	super.onSaveInstanceState(outState);
	outState.putLong(BUNDLE_KEY_TAG_ID_IN_EDIT, mTagIdInEdit);
	}

	@Override
	protected void onDestroy() {
	if (mAdapter != null) {
	mAdapter.changeCursor(null);
	}
	super.onDestroy();
	}

	@Override
	public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
	editTag(id);
	}

	/**
	* Opens the tag editor for a particular tag.
	*/
	private void editTag(long id) {
	// TODO: use implicit Intent?
	Intent intent = new Intent(this, EditTagActivity.class);
	intent.setData(ContentUris.withAppendedId(NdefMessages.CONTENT_URI, id));
	mTagIdInEdit = id;
	startActivityForResult(intent, REQUEST_EDIT);
	}

	public void setEmptyView() {
	// TODO: set empty view.
	}

	public interface TagQuery {
	static final String[] PROJECTION = new String[] {
	NdefMessages._ID, // 0
	NdefMessages.DATE, // 1
	NdefMessages.TITLE, // 2
	NdefMessages.BYTES, // 3
	};

	static final int COLUMN_ID = 0;
	static final int COLUMN_DATE = 1;
	static final int COLUMN_TITLE = 2;
	static final int COLUMN_BYTES = 3;
	}

	/**
	* Asynchronously loads the tags info from the database.
	*/
	final class TagLoaderTask extends AsyncTask<Void, Void, Cursor> {
	@Override
	public Cursor doInBackground(Void... args) {
	Cursor cursor = getContentResolver().query(
	NdefMessages.CONTENT_URI,
	TagQuery.PROJECTION,
	NdefMessages.IS_MY_TAG + "=1",
	null, NdefMessages.DATE + " DESC");

	// Ensure the cursor executes and fills its window
	if (cursor != null) cursor.getCount();
	return cursor;
	}

	@Override
	protected void onPostExecute(Cursor cursor) {
	mAdapter.changeCursor(cursor);

	if (cursor == null \|\| cursor.getCount() == 0) {
	setEmptyView();
	} else {
	// Find the active tag.
	if (mTagBeingSaved != null) {
	selectTagBeingSaved(mTagBeingSaved);

	} else if (mActiveTagId != -1) {
	cursor.moveToPosition(-1);
	while (cursor.moveToNext()) {
	if (mActiveTagId == cursor.getLong(TagQuery.COLUMN_ID)) {
	selectActiveTag(cursor.getPosition());
	break;
	}
	}
	}
	}


	SelectActiveTagDialog dialog = (mSelectActiveTagDialog == null)
	? null : mSelectActiveTagDialog.get();
	if (dialog != null) {
	dialog.setData(cursor);
	}
	}
	}

	/**
	* Struct to hold pointers to views in the list items to save time at view binding time.
	*/
	static final class ViewHolder {
	public CharArrayBuffer titleBuffer;
	public TextView mainLine;
	public ImageView activeIcon;
	}

	/**
	* Adapter to display the the My tag entries.
	*/
	public class TagAdapter extends CursorAdapter {
	private final LayoutInflater mInflater;

	public TagAdapter(Context context) {
	super(context, null, false);
	mInflater = LayoutInflater.from(context);
	}

	@Override
	public void bindView(View view, Context context, Cursor cursor) {
	ViewHolder holder = (ViewHolder) view.getTag();

	CharArrayBuffer buf = holder.titleBuffer;
	cursor.copyStringToBuffer(TagQuery.COLUMN_TITLE, buf);
	holder.mainLine.setText(buf.data, 0, buf.sizeCopied);

	boolean isActive = cursor.getLong(TagQuery.COLUMN_ID) == mActiveTagId;
	holder.activeIcon.setVisibility(isActive ? View.VISIBLE : View.GONE);
	}

	@Override
	public View newView(Context context, Cursor cursor, ViewGroup parent) {
	View view = mInflater.inflate(R.layout.tag_list_item, null);

	// Cache items for the view
	ViewHolder holder = new ViewHolder();
	holder.titleBuffer = new CharArrayBuffer(64);
	holder.mainLine = (TextView) view.findViewById(R.id.title);
	holder.activeIcon = (ImageView) view.findViewById(R.id.active_tag_icon);
	view.findViewById(R.id.date).setVisibility(View.GONE);
	view.setTag(holder);

	return view;
	}

	@Override
	public void onContentChanged() {
	// Kick off an async query to refresh the list
	new TagLoaderTask().execute((Void[]) null);
	}
	}

	@Override
	public void onClick(View target) {
	switch (target.getId()) {
	case R.id.toggle_enabled_target:
	boolean enabled = !mEnabled.isChecked();
	if (enabled) {
	if (mActiveTag != null) {
	enableSharingAndStoreTag();
	return;
	}
	Toast.makeText(
	this,
	getResources().getString(R.string.no_tag_selected),
	Toast.LENGTH_SHORT).show();
	}

	disableSharing();
	break;

	case R.id.add_tag:
	showDialog(DIALOG_ID_ADD_NEW_TAG);
	break;

	case R.id.active_tag:
	if (mAdapter.getCursor() == null \|\| mAdapter.getCursor().isClosed()) {
	// Hopefully shouldn't happen.
	return;
	}

	if (mAdapter.getCursor().getCount() == 0) {
	OnClickListener onAdd = new OnClickListener() {
	@Override
	public void onClick(DialogInterface dialog, int which) {
	if (which == AlertDialog.BUTTON_POSITIVE) {
	showDialog(DIALOG_ID_ADD_NEW_TAG);
	}
	}
	};
	new AlertDialog.Builder(this)
	.setNegativeButton(android.R.string.cancel, null)
	.setPositiveButton(R.string.add_tag, onAdd)
	.setMessage(R.string.no_tags_created)
	.show();
	return;
	}
	showDialog(DIALOG_ID_SELECT_ACTIVE_TAG);
	break;
	}
	}

	@Override
	public void onCreateContextMenu(ContextMenu menu, View view, ContextMenuInfo info) {
	Cursor cursor = mAdapter.getCursor();
	if (cursor == null
	\|\| cursor.isClosed()
	\|\| !cursor.moveToPosition(((AdapterContextMenuInfo) info).position)) {
	return;
	}

	menu.setHeaderTitle(cursor.getString(TagQuery.COLUMN_TITLE));
	long id = cursor.getLong(TagQuery.COLUMN_ID);
	MenuInflater inflater = getMenuInflater();
	inflater.inflate(R.menu.my_tag_list_context_menu, menu);

	// Prepare the menu for the item.
	menu.findItem(R.id.set_as_active).setVisible(id != mActiveTagId);
	mTagIdLongPressed = id;

	if (mWriteSupport) {
	menu.add(0, 1, 0, "Write to tag");
	}
	}

	@Override
	public boolean onContextItemSelected(MenuItem item) {
	long id = mTagIdLongPressed;
	switch (item.getItemId()) {
	case R.id.delete:
	deleteTag(id);
	return true;

	case R.id.set_as_active:
	Cursor cursor = mAdapter.getCursor();
	if (cursor == null \|\| cursor.isClosed()) {
	break;
	}

	for (int position = 0; cursor.moveToPosition(position); position++) {
	if (cursor.getLong(TagQuery.COLUMN_ID) == id) {
	selectActiveTag(position);
	return true;
	}
	}
	break;

	case R.id.edit:
	editTag(id);
	return true;

	case 1:
	AdapterView.AdapterContextMenuInfo info;
	try {
	info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
	} catch (ClassCastException e) {
	Log.e(TAG, "bad menuInfo", e);
	break;
	}

	Intent intent = new Intent(this, WriteTagActivity.class);
	intent.putExtra("id", info.id);
	startActivity(intent);
	return true;
	}
	return false;
	}

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
	if (requestCode == REQUEST_EDIT && resultCode == RESULT_OK) {
	NdefMessage msg = (NdefMessage) Preconditions.checkNotNull(
	data.getParcelableExtra(EditTagActivity.EXTRA_RESULT_MSG));

	if (mTagIdInEdit != -1) {
	TagService.updateMyMessage(this, mTagIdInEdit, msg);
	} else {
	saveNewMessage(msg);
	}
	}
	}

	private void saveNewMessage(NdefMessage msg) {
	TagService.saveMyMessage(this, msg, this);
	}

	@Override
	public void onSaveComplete(Uri newMsgUri) {
	if (isFinishing()) {
	// Callback came asynchronously and was after we finished - ignore.
	return;
	}
	mTagBeingSaved = newMsgUri;
	selectTagBeingSaved(newMsgUri);
	}

	@Override
	protected Dialog onCreateDialog(int id, Bundle args) {
	Context lightTheme = new ContextThemeWrapper(this, android.R.style.Theme_Light);
	if (id == DIALOG_ID_SELECT_ACTIVE_TAG) {
	SelectActiveTagDialog dialog = new SelectActiveTagDialog(lightTheme,
	mAdapter.getCursor());
	dialog.setInverseBackgroundForced(true);
	mSelectActiveTagDialog = new WeakReference<SelectActiveTagDialog>(dialog);
	return dialog;
	} else if (id == DIALOG_ID_ADD_NEW_TAG) {
	ContentSelectorAdapter adapter = new ContentSelectorAdapter(lightTheme,
	SUPPORTED_TYPES);
	AlertDialog dialog = new AlertDialog.Builder(lightTheme)
	.setTitle(R.string.select_type)
	.setIcon(0)
	.setNegativeButton(android.R.string.cancel, this)
	.setAdapter(adapter, this)
	.create();
	adapter.setListView(dialog.getListView());
	dialog.setInverseBackgroundForced(true);
	return dialog;
	}
	return super.onCreateDialog(id, args);
	}

	@Override
	public void onClick(DialogInterface dialog, int which) {
	if (which == DialogInterface.BUTTON_NEGATIVE) {
	dialog.cancel();
	} else {
	RecordEditInfo info = (RecordEditInfo) ((AlertDialog) dialog).getListView()
	.getAdapter().getItem(which);
	Intent intent = new Intent(this, EditTagActivity.class);
	intent.putExtra(EditTagActivity.EXTRA_NEW_RECORD_INFO, info);
	startActivityForResult(intent, REQUEST_EDIT);
	}
	}

	/**
	* Selects the tag to be used as the "My tag" shared tag.
	*
	* This does not necessarily persist the selection to the {@code NfcAdapter}. That must be done
	* via {@link #enableSharingAndStoreTag()}. However, it will call {@link #disableSharing()}
	* if the tag is invalid.
	*/
	private void selectActiveTag(int position) {
	Cursor cursor = mAdapter.getCursor();
	if (cursor != null && cursor.moveToPosition(position)) {
	mActiveTagId = cursor.getLong(TagQuery.COLUMN_ID);

	try {
	mActiveTag = new NdefMessage(cursor.getBlob(TagQuery.COLUMN_BYTES));

	// Persist active tag info to preferences.
	getPreferences(Context.MODE_PRIVATE)
	.edit()
	.putLong(PREF_KEY_ACTIVE_TAG, mActiveTagId)
	.apply();

	updateActiveTagView(cursor.getString(TagQuery.COLUMN_TITLE));
	mAdapter.notifyDataSetChanged();

	// If there was an existing shared tag, we update the contents, since
	// the active tag contents may have been changed. This also forces the
	// active tag to be in sync with what the NfcAdapter.
	if (NfcAdapter.getDefaultAdapter(this).getLocalNdefMessage() != null) {
	enableSharingAndStoreTag();
	}

	} catch (FormatException e) {
	// TODO: handle.
	disableSharing();
	}
	} else {
	updateActiveTagView(null);
	disableSharing();
	}
	mTagBeingSaved = null;
	}

	/**
	* Selects the tag to be used as the "My tag" shared tag, if the specified URI is found.
	* If the URI is not found, the next load will attempt to look for a matching tag to select.
	*
	* Commonly used for new tags that was just added to the database, and may not yet be
	* reflected in the {@code Cursor}.
	*/
	private void selectTagBeingSaved(Uri uri) {
	Cursor cursor = mAdapter.getCursor();
	if (cursor == null) {
	return;
	}
	cursor.moveToPosition(-1);
	while (cursor.moveToNext()) {
	Uri tagUri = ContentUris.withAppendedId(
	NdefMessages.CONTENT_URI,
	cursor.getLong(TagQuery.COLUMN_ID));
	if (tagUri.equals(uri)) {
	selectActiveTag(cursor.getPosition());
	return;
	}
	}
	}

	private void enableSharingAndStoreTag() {
	mEnabled.setChecked(true);
	NfcAdapter.getDefaultAdapter(this).setLocalNdefMessage(
	Preconditions.checkNotNull(mActiveTag));
	}

	private void disableSharing() {
	mEnabled.setChecked(false);
	NfcAdapter.getDefaultAdapter(this).setLocalNdefMessage(null);
	}

	private void updateActiveTagView(String title) {
	if (title == null) {
	mActiveTagDetails.setVisibility(View.GONE);
	mSelectActiveTagAnchor.setVisibility(View.VISIBLE);
	} else {
	mActiveTagDetails.setVisibility(View.VISIBLE);
	((TextView) mActiveTagDetails.findViewById(R.id.active_tag_title)).setText(title);
	mSelectActiveTagAnchor.setVisibility(View.GONE);
	}
	}

	/**
	* Removes the tag from the "My tag" list.
	*/
	private void deleteTag(long id) {
	if (id == mActiveTagId) {
	selectActiveTag(-1);
	}
	TagService.delete(this, ContentUris.withAppendedId(NdefMessages.CONTENT_URI, id));
	}

	class SelectActiveTagDialog extends AlertDialog
	implements DialogInterface.OnClickListener, OnItemClickListener {

	private final ArrayList<HashMap<String, String>> mData;
	private final SimpleAdapter mSelectAdapter;

	protected SelectActiveTagDialog(Context context, Cursor cursor) {
	super(context);

	setTitle(context.getResources().getString(R.string.choose_my_tag));
	ListView list = new ListView(context);

	mData = Lists.newArrayList();
	mSelectAdapter = new SimpleAdapter(
	context,
	mData,
	android.R.layout.simple_list_item_1,
	new String[] { "title" },
	new int[] { android.R.id.text1 });

	list.setAdapter(mSelectAdapter);
	list.setOnItemClickListener(this);
	setView(list);
	setIcon(0);
	setButton(
	DialogInterface.BUTTON_POSITIVE,
	context.getString(android.R.string.cancel),
	this);

	setData(cursor);
	}

	public void setData(final Cursor cursor) {
	if ((cursor == null) \|\| (cursor.getCount() == 0)) {
	cancel();
	return;
	}
	mData.clear();

	cursor.moveToPosition(-1);
	while (cursor.moveToNext()) {
	mData.add(new HashMap<String, String>() {{
	put("title", cursor.getString(MyTagList.TagQuery.COLUMN_TITLE));
	}});
	}

	mSelectAdapter.notifyDataSetChanged();
	}

	@Override
	public void onClick(DialogInterface dialog, int which) {
	cancel();
	}

	@Override
	public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
	selectActiveTag(position);
	enableSharingAndStoreTag();
	cancel();
	}
	}
	}