samples/NotePad/src/com/example/android/notepad/NoteEditor.java - platform/development - Git at Google

 /*
  * Copyright (C) 2007 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.example.android.notepad;

 import android.app.Activity;
 import android.app.LoaderManager;
 import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.ComponentName;
 import android.content.ContentResolver;
 import android.content.ContentValues;
 import android.content.Context;
 import android.content.CursorLoader;
 import android.content.Intent;
 import android.content.Loader;
 import android.content.res.Resources;
 import android.database.Cursor;
 import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.Rect;
 import android.net.Uri;
 import android.os.Bundle;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.widget.EditText;
 import com.example.android.notepad.NotePad.Notes;

 /**
  * This Activity handles "editing" a note, where editing is responding to
  * {@link Intent#ACTION_VIEW} (request to view data), edit a note
  * {@link Intent#ACTION_EDIT}, create a note {@link Intent#ACTION_INSERT}, or
  * create a new note from the current contents of the clipboard {@link Intent#ACTION_PASTE}.
  */
 public class NoteEditor extends Activity implements LoaderManager.LoaderCallbacks<Cursor> {
     // For logging and debugging purposes
     private static final String TAG = "NoteEditor";

     /*
      * Creates a projection that returns the note ID and the note contents.
      */
     private static final String[] PROJECTION =
         new String[] {
             NotePad.Notes._ID,
             NotePad.Notes.COLUMN_NAME_TITLE,
             NotePad.Notes.COLUMN_NAME_NOTE
     };

     // A label for the saved state of the activity
     private static final String ORIGINAL_CONTENT = "origContent";

     // This Activity can be started by more than one action. Each action is represented
     // as a "state" constant
     private static final int STATE_EDIT = 0;
     private static final int STATE_INSERT = 1;

     private static final int LOADER_ID = 1;

     // Global mutable variables
     private int mState;
     private Uri mUri;
     private EditText mText;
     private String mOriginalContent;

     /**
      * Defines a custom EditText View that draws lines between each line of text that is displayed.
      */
     public static class LinedEditText extends EditText {
         private Rect mRect;
         private Paint mPaint;

         // This constructor is used by LayoutInflater
         public LinedEditText(Context context, AttributeSet attrs) {
             super(context, attrs);

             // Creates a Rect and a Paint object, and sets the style and color of the Paint object.
             mRect = new Rect();
             mPaint = new Paint();
             mPaint.setStyle(Paint.Style.STROKE);
             mPaint.setColor(0x800000FF);
         }

         /**
          * This is called to draw the LinedEditText object
          * @param canvas The canvas on which the background is drawn.
          */
         @Override
         protected void onDraw(Canvas canvas) {

             // Gets the number of lines of text in the View.
             int count = getLineCount();

             // Gets the global Rect and Paint objects
             Rect r = mRect;
             Paint paint = mPaint;

             /*
              * Draws one line in the rectangle for every line of text in the EditText
              */
             for (int i = 0; i < count; i++) {

                 // Gets the baseline coordinates for the current line of text
                 int baseline = getLineBounds(i, r);

                 /*
                  * Draws a line in the background from the left of the rectangle to the right,
                  * at a vertical position one dip below the baseline, using the "paint" object
                  * for details.
                  */
                 canvas.drawLine(r.left, baseline + 1, r.right, baseline + 1, paint);
             }

             // Finishes up by calling the parent method
             super.onDraw(canvas);
         }
     }

     /**
      * This method is called by Android when the Activity is first started. From the incoming
      * Intent, it determines what kind of editing is desired, and then does it.
      */
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         // Recovering the instance state from a previously destroyed Activity instance
         if (savedInstanceState != null) {
             mOriginalContent = savedInstanceState.getString(ORIGINAL_CONTENT);
         }

         /*
          * Creates an Intent to use when the Activity object's result is sent back to the
          * caller.
          */
         final Intent intent = getIntent();

         /*
          *  Sets up for the edit, based on the action specified for the incoming Intent.
          */

         // Gets the action that triggered the intent filter for this Activity
         final String action = intent.getAction();

         // For an edit action:
         if (Intent.ACTION_EDIT.equals(action)) {

             // Sets the Activity state to EDIT, and gets the URI for the data to be edited.
             mState = STATE_EDIT;
             mUri = intent.getData();

             // For an insert or paste action:
         } else if (Intent.ACTION_INSERT.equals(action)
                 || Intent.ACTION_PASTE.equals(action)) {

             // Sets the Activity state to INSERT, gets the general note URI, and inserts an
             // empty record in the provider
             mState = STATE_INSERT;
             setTitle(getText(R.string.title_create));

             mUri = getContentResolver().insert(intent.getData(), null);

             /*
              * If the attempt to insert the new note fails, shuts down this Activity. The
              * originating Activity receives back RESULT_CANCELED if it requested a result.
              * Logs that the insert failed.
              */
             if (mUri == null) {

                 // Writes the log identifier, a message, and the URI that failed.
                 Log.e(TAG, "Failed to insert new note into " + getIntent().getData());

                 // Closes the activity.
                 finish();
                 return;
             }

             // Since the new entry was created, this sets the result to be returned
             // set the result to be returned.
             setResult(RESULT_OK, (new Intent()).setAction(mUri.toString()));

         // If the action was other than EDIT or INSERT:
         } else {

             // Logs an error that the action was not understood, finishes the Activity, and
             // returns RESULT_CANCELED to an originating Activity.
             Log.e(TAG, "Unknown action, exiting");
             finish();
             return;
         }

         // Initialize the LoaderManager and start the query
         getLoaderManager().initLoader(LOADER_ID, null, this);

         // For a paste, initializes the data from clipboard.
         if (Intent.ACTION_PASTE.equals(action)) {
             // Does the paste
             performPaste();
             // Switches the state to EDIT so the title can be modified.
             mState = STATE_EDIT;
         }

         // Sets the layout for this Activity. See res/layout/note_editor.xml
         setContentView(R.layout.note_editor);

         // Gets a handle to the EditText in the the layout.
         mText = (EditText) findViewById(R.id.note);
     }


     /**
      * This method is called when an Activity loses focus during its normal operation.
      * The Activity has a chance to save its state so that the system can restore
      * it.
      *
      * Notice that this method isn't a normal part of the Activity lifecycle. It won't be called
      * if the user simply navigates away from the Activity.
      */
     @Override
     protected void onSaveInstanceState(Bundle outState) {
         // Save away the original text, so we still have it if the activity
         // needs to be re-created.
         outState.putString(ORIGINAL_CONTENT, mOriginalContent);
         // Call the superclass to save the any view hierarchy state
         super.onSaveInstanceState(outState);
     }

     /**
      * This method is called when the Activity loses focus.
      *
      * While there is no need to override this method in this app, it is shown here to highlight
      * that we are not saving any state in onPause, but have moved app state saving to onStop
      * callback.
      * In earlier versions of this app and popular literature it had been shown that onPause is good
      * place to persist any unsaved work, however, this is not really a good practice because of how
      * application and process lifecycle behave.
      * As a general guideline apps should have a way of saving their business logic that does not
      * solely rely on Activity (or other component) lifecyle state transitions.
      * As a backstop you should save any app state, not saved during lifetime of the Activity, in
      * onStop().
      * For a more detailed explanation of this recommendation please read
      * <a href = "https://developer.android.com/guide/topics/processes/process-lifecycle.html">
      * Processes and Application Life Cycle </a>.
      * <a href="https://developer.android.com/training/basics/activity-lifecycle/pausing.html">
      * Pausing and Resuming an Activity </a>.
      */
     @Override
     protected void onPause() {
         super.onPause();
     }

     /**
      * This method is called when the Activity becomes invisible.
      *
      * For Activity objects that edit information, onStop() may be the one place where changes maybe
      * saved.
      *
      * If the user hasn't done anything, then this deletes or clears out the note, otherwise it
      * writes the user's work to the provider.
      */
     @Override
     protected void onStop() {
         super.onStop();

         // Get the current note text.
         String text = mText.getText().toString();
         int length = text.length();

             /*
              * If the Activity is in the midst of finishing and there is no text in the current
              * note, returns a result of CANCELED to the caller, and deletes the note. This is done
              * even if the note was being edited, the assumption being that the user wanted to
              * "clear out" (delete) the note.
              */
         if (isFinishing() && (length == 0)) {
             setResult(RESULT_CANCELED);
             deleteNote();

                 /*
                  * Writes the edits to the provider. The note has been edited if an existing note
                  * was retrieved into the editor *or* if a new note was inserted.
                  * In the latter case, onCreate() inserted a new empty note into the provider,
                  * and it is this new note that is being edited.
                  */
         } else if (mState == STATE_EDIT) {
             // Creates a map to contain the new values for the columns
             updateNote(text, null);
         } else if (mState == STATE_INSERT) {
             updateNote(text, text);
             mState = STATE_EDIT;
         }
     }

     /**
      * This method is called when the user clicks the device's Menu button the first time for
      * this Activity. Android passes in a Menu object that is populated with items.
      *
      * Builds the menus for editing and inserting, and adds in alternative actions that
      * registered themselves to handle the MIME types for this application.
      *
      * @param menu A Menu object to which items should be added.
      * @return True to display the menu.
      */
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         // Inflate menu from XML resource
         MenuInflater inflater = getMenuInflater();
         inflater.inflate(R.menu.editor_options_menu, menu);

         // Only add extra menu items for a saved note
         if (mState == STATE_EDIT) {
             // Append to the
             // menu items for any other activities that can do stuff with it
             // as well.  This does a query on the system for any activities that
             // implement the ALTERNATIVE_ACTION for our data, adding a menu item
             // for each one that is found.
             Intent intent = new Intent(null, mUri);
             intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
             menu.addIntentOptions(Menu.CATEGORY_ALTERNATIVE, 0, 0,
                     new ComponentName(this, NoteEditor.class), null, intent, 0, null);
         }

         return super.onCreateOptionsMenu(menu);
     }

     @Override
     public boolean onPrepareOptionsMenu(Menu menu) {
         // Check if note has changed and enable/disable the revert option
         Cursor cursor = getContentResolver().query(
             mUri,        // The URI for the note that is to be retrieved.
             PROJECTION,  // The columns to retrieve
             null,        // No selection criteria are used, so no where columns are needed.
             null,        // No where columns are used, so no where values are needed.
             null         // No sort order is needed.
         );
         cursor.moveToFirst();
         int colNoteIndex = cursor.getColumnIndex(Notes.COLUMN_NAME_NOTE);
         String savedNote = cursor.getString(colNoteIndex);
         String currentNote = mText.getText().toString();
         if (savedNote.equals(currentNote)) {
             menu.findItem(R.id.menu_revert).setVisible(false);
         } else {
             menu.findItem(R.id.menu_revert).setVisible(true);
         }
         return super.onPrepareOptionsMenu(menu);
     }

     /**
      * This method is called when a menu item is selected. Android passes in the selected item.
      * The switch statement in this method calls the appropriate method to perform the action the
      * user chose.
      *
      * @param item The selected MenuItem
      * @return True to indicate that the item was processed, and no further work is necessary. False
      * to proceed to further processing as indicated in the MenuItem object.
      */
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         // Handle all of the possible menu actions.
         switch (item.getItemId()) {
         case R.id.menu_save:
             String text = mText.getText().toString();
             updateNote(text, null);
             finish();
             break;
         case R.id.menu_delete:
             deleteNote();
             finish();
             break;
         case R.id.menu_revert:
             cancelNote();
             break;
         }
         return super.onOptionsItemSelected(item);
     }

 //BEGIN_INCLUDE(paste)
     /**
      * A helper method that replaces the note's data with the contents of the clipboard.
      */
     private final void performPaste() {

         // Gets a handle to the Clipboard Manager
         ClipboardManager clipboard = (ClipboardManager)
                 getSystemService(Context.CLIPBOARD_SERVICE);

         // Gets a content resolver instance
         ContentResolver cr = getContentResolver();

         // Gets the clipboard data from the clipboard
         ClipData clip = clipboard.getPrimaryClip();
         if (clip != null) {

             String text=null;
             String title=null;

             // Gets the first item from the clipboard data
             ClipData.Item item = clip.getItemAt(0);

             // Tries to get the item's contents as a URI pointing to a note
             Uri uri = item.getUri();

             // Tests to see that the item actually is an URI, and that the URI
             // is a content URI pointing to a provider whose MIME type is the same
             // as the MIME type supported by the Note pad provider.
             if (uri != null && NotePad.Notes.CONTENT_ITEM_TYPE.equals(cr.getType(uri))) {

                 // The clipboard holds a reference to data with a note MIME type. This copies it.
                 Cursor orig = cr.query(
                         uri,            // URI for the content provider
                         PROJECTION,     // Get the columns referred to in the projection
                         null,           // No selection variables
                         null,           // No selection variables, so no criteria are needed
                         null            // Use the default sort order
                 );

                 // If the Cursor is not null, and it contains at least one record
                 // (moveToFirst() returns true), then this gets the note data from it.
                 if (orig != null) {
                     if (orig.moveToFirst()) {
                         int colNoteIndex = orig.getColumnIndex(NotePad.Notes.COLUMN_NAME_NOTE);
                         int colTitleIndex = orig.getColumnIndex(NotePad.Notes.COLUMN_NAME_TITLE);
                         text = orig.getString(colNoteIndex);
                         title = orig.getString(colTitleIndex);
                     }

                     // Closes the cursor.
                     orig.close();
                 }
             }

             // If the contents of the clipboard wasn't a reference to a note, then
             // this converts whatever it is to text.
             if (text == null) {
                 text = item.coerceToText(this).toString();
             }

             // Updates the current note with the retrieved title and text.
             updateNote(text, title);
         }
     }
 //END_INCLUDE(paste)

     /**
      * Replaces the current note contents with the text and title provided as arguments.
      * @param text The new note contents to use.
      * @param title The new note title to use
      */
     private final void updateNote(String text, String title) {

         // Sets up a map to contain values to be updated in the provider.
         ContentValues values = new ContentValues();
         values.put(NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE, System.currentTimeMillis());

         // If the action is to insert a new note, this creates an initial title for it.
         if (mState == STATE_INSERT) {

             // If no title was provided as an argument, create one from the note text.
             if (title == null) {

                 // Get the note's length
                 int length = text.length();

                 // Sets the title by getting a substring of the text that is 31 characters long
                 // or the number of characters in the note plus one, whichever is smaller.
                 title = text.substring(0, Math.min(30, length));

                 // If the resulting length is more than 30 characters, chops off any
                 // trailing spaces
                 if (length > 30) {
                     int lastSpace = title.lastIndexOf(' ');
                     if (lastSpace > 0) {
                         title = title.substring(0, lastSpace);
                     }
                 }
             }
             // In the values map, sets the value of the title
             values.put(NotePad.Notes.COLUMN_NAME_TITLE, title);
         } else if (title != null) {
             // In the values map, sets the value of the title
             values.put(NotePad.Notes.COLUMN_NAME_TITLE, title);
         }

         // This puts the desired notes text into the map.
         values.put(NotePad.Notes.COLUMN_NAME_NOTE, text);

         /*
          * Updates the provider with the new values in the map. The ListView is updated
          * automatically. The provider sets this up by setting the notification URI for
          * query Cursor objects to the incoming URI. The content resolver is thus
          * automatically notified when the Cursor for the URI changes, and the UI is
          * updated.
          * Note: This is being done on the UI thread. It will block the thread until the
          * update completes. In a sample app, going against a simple provider based on a
          * local database, the block will be momentary, but in a real app you should use
          * android.content.AsyncQueryHandler or android.os.AsyncTask.
          */
         getContentResolver().update(
             mUri,    // The URI for the record to update.
             values,  // The map of column names and new values to apply to them.
             null,    // No selection criteria are used, so no where columns are necessary.
             null     // No where columns are used, so no where arguments are necessary.
         );
     }

     /**
      * This helper method cancels the work done on a note.  It deletes the note if it was
      * newly created, or reverts to the original text of the note i
      */
     private final void cancelNote() {

         if (mState == STATE_EDIT) {
             // Put the original note text back into the database
             ContentValues values = new ContentValues();
             values.put(NotePad.Notes.COLUMN_NAME_NOTE, mOriginalContent);
             getContentResolver().update(mUri, values, null, null);
         } else if (mState == STATE_INSERT) {
             // We inserted an empty note, make sure to delete it
             deleteNote();
         }

         setResult(RESULT_CANCELED);
         finish();
     }

     /**
      * Take care of deleting a note.  Simply deletes the entry.
      */
     private final void deleteNote() {
         getContentResolver().delete(mUri, null, null);
         mText.setText("");
     }

     // LoaderManager callbacks
     @Override
     public Loader<Cursor> onCreateLoader(int i, Bundle bundle) {
         return new CursorLoader(
             this,
             mUri,        // The URI for the note that is to be retrieved.
             PROJECTION,  // The columns to retrieve
             null,        // No selection criteria are used, so no where columns are needed.
             null,        // No where columns are used, so no where values are needed.
             null         // No sort order is needed.
         );
     }

     @Override
     public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) {

         // Modifies the window title for the Activity according to the current Activity state.
         if (cursor != null && cursor.moveToFirst() && mState == STATE_EDIT) {
             // Set the title of the Activity to include the note title
             int colTitleIndex = cursor.getColumnIndex(NotePad.Notes.COLUMN_NAME_TITLE);
             int colNoteIndex = cursor.getColumnIndex(NotePad.Notes.COLUMN_NAME_NOTE);

             // Gets the title and sets it
             String title = cursor.getString(colTitleIndex);
             Resources res = getResources();
             String text = String.format(res.getString(R.string.title_edit), title);
             setTitle(text);

             // Gets the note text from the Cursor and puts it in the TextView, but doesn't change
             // the text cursor's position.

             String note = cursor.getString(colNoteIndex);
             mText.setTextKeepState(note);
             // Stores the original note text, to allow the user to revert changes.
             if (mOriginalContent == null) {
                 mOriginalContent = note;
             }
         }
     }

     @Override
     public void onLoaderReset(Loader<Cursor> cursorLoader) {}
 }
	/*
	* Copyright (C) 2007 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.example.android.notepad;

	import android.app.Activity;
	import android.app.LoaderManager;
	import android.content.ClipData;
	import android.content.ClipboardManager;
	import android.content.ComponentName;
	import android.content.ContentResolver;
	import android.content.ContentValues;
	import android.content.Context;
	import android.content.CursorLoader;
	import android.content.Intent;
	import android.content.Loader;
	import android.content.res.Resources;
	import android.database.Cursor;
	import android.graphics.Canvas;
	import android.graphics.Paint;
	import android.graphics.Rect;
	import android.net.Uri;
	import android.os.Bundle;
	import android.util.AttributeSet;
	import android.util.Log;
	import android.view.Menu;
	import android.view.MenuInflater;
	import android.view.MenuItem;
	import android.widget.EditText;
	import com.example.android.notepad.NotePad.Notes;

	/**
	* This Activity handles "editing" a note, where editing is responding to
	* {@link Intent#ACTION_VIEW} (request to view data), edit a note
	* {@link Intent#ACTION_EDIT}, create a note {@link Intent#ACTION_INSERT}, or
	* create a new note from the current contents of the clipboard {@link Intent#ACTION_PASTE}.
	*/
	public class NoteEditor extends Activity implements LoaderManager.LoaderCallbacks<Cursor> {
	// For logging and debugging purposes
	private static final String TAG = "NoteEditor";

	/*
	* Creates a projection that returns the note ID and the note contents.
	*/
	private static final String[] PROJECTION =
	new String[] {
	NotePad.Notes._ID,
	NotePad.Notes.COLUMN_NAME_TITLE,
	NotePad.Notes.COLUMN_NAME_NOTE
	};

	// A label for the saved state of the activity
	private static final String ORIGINAL_CONTENT = "origContent";

	// This Activity can be started by more than one action. Each action is represented
	// as a "state" constant
	private static final int STATE_EDIT = 0;
	private static final int STATE_INSERT = 1;

	private static final int LOADER_ID = 1;

	// Global mutable variables
	private int mState;
	private Uri mUri;
	private EditText mText;
	private String mOriginalContent;

	/**
	* Defines a custom EditText View that draws lines between each line of text that is displayed.
	*/
	public static class LinedEditText extends EditText {
	private Rect mRect;
	private Paint mPaint;

	// This constructor is used by LayoutInflater
	public LinedEditText(Context context, AttributeSet attrs) {
	super(context, attrs);

	// Creates a Rect and a Paint object, and sets the style and color of the Paint object.
	mRect = new Rect();
	mPaint = new Paint();
	mPaint.setStyle(Paint.Style.STROKE);
	mPaint.setColor(0x800000FF);
	}

	/**
	* This is called to draw the LinedEditText object
	* @param canvas The canvas on which the background is drawn.
	*/
	@Override
	protected void onDraw(Canvas canvas) {

	// Gets the number of lines of text in the View.
	int count = getLineCount();

	// Gets the global Rect and Paint objects
	Rect r = mRect;
	Paint paint = mPaint;

	/*
	* Draws one line in the rectangle for every line of text in the EditText
	*/
	for (int i = 0; i < count; i++) {

	// Gets the baseline coordinates for the current line of text
	int baseline = getLineBounds(i, r);

	/*
	* Draws a line in the background from the left of the rectangle to the right,
	* at a vertical position one dip below the baseline, using the "paint" object
	* for details.
	*/
	canvas.drawLine(r.left, baseline + 1, r.right, baseline + 1, paint);
	}

	// Finishes up by calling the parent method
	super.onDraw(canvas);
	}
	}

	/**
	* This method is called by Android when the Activity is first started. From the incoming
	* Intent, it determines what kind of editing is desired, and then does it.
	*/
	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	// Recovering the instance state from a previously destroyed Activity instance
	if (savedInstanceState != null) {
	mOriginalContent = savedInstanceState.getString(ORIGINAL_CONTENT);
	}

	/*
	* Creates an Intent to use when the Activity object's result is sent back to the
	* caller.
	*/
	final Intent intent = getIntent();

	/*
	* Sets up for the edit, based on the action specified for the incoming Intent.
	*/

	// Gets the action that triggered the intent filter for this Activity
	final String action = intent.getAction();

	// For an edit action:
	if (Intent.ACTION_EDIT.equals(action)) {

	// Sets the Activity state to EDIT, and gets the URI for the data to be edited.
	mState = STATE_EDIT;
	mUri = intent.getData();

	// For an insert or paste action:
	} else if (Intent.ACTION_INSERT.equals(action)
	\|\| Intent.ACTION_PASTE.equals(action)) {

	// Sets the Activity state to INSERT, gets the general note URI, and inserts an
	// empty record in the provider
	mState = STATE_INSERT;
	setTitle(getText(R.string.title_create));

	mUri = getContentResolver().insert(intent.getData(), null);

	/*
	* If the attempt to insert the new note fails, shuts down this Activity. The
	* originating Activity receives back RESULT_CANCELED if it requested a result.
	* Logs that the insert failed.
	*/
	if (mUri == null) {

	// Writes the log identifier, a message, and the URI that failed.
	Log.e(TAG, "Failed to insert new note into " + getIntent().getData());

	// Closes the activity.
	finish();
	return;
	}

	// Since the new entry was created, this sets the result to be returned
	// set the result to be returned.
	setResult(RESULT_OK, (new Intent()).setAction(mUri.toString()));

	// If the action was other than EDIT or INSERT:
	} else {

	// Logs an error that the action was not understood, finishes the Activity, and
	// returns RESULT_CANCELED to an originating Activity.
	Log.e(TAG, "Unknown action, exiting");
	finish();
	return;
	}

	// Initialize the LoaderManager and start the query
	getLoaderManager().initLoader(LOADER_ID, null, this);

	// For a paste, initializes the data from clipboard.
	if (Intent.ACTION_PASTE.equals(action)) {
	// Does the paste
	performPaste();
	// Switches the state to EDIT so the title can be modified.
	mState = STATE_EDIT;
	}

	// Sets the layout for this Activity. See res/layout/note_editor.xml
	setContentView(R.layout.note_editor);

	// Gets a handle to the EditText in the the layout.
	mText = (EditText) findViewById(R.id.note);
	}


	/**
	* This method is called when an Activity loses focus during its normal operation.
	* The Activity has a chance to save its state so that the system can restore
	* it.
	*
	* Notice that this method isn't a normal part of the Activity lifecycle. It won't be called
	* if the user simply navigates away from the Activity.
	*/
	@Override
	protected void onSaveInstanceState(Bundle outState) {
	// Save away the original text, so we still have it if the activity
	// needs to be re-created.
	outState.putString(ORIGINAL_CONTENT, mOriginalContent);
	// Call the superclass to save the any view hierarchy state
	super.onSaveInstanceState(outState);
	}

	/**
	* This method is called when the Activity loses focus.
	*
	* While there is no need to override this method in this app, it is shown here to highlight
	* that we are not saving any state in onPause, but have moved app state saving to onStop
	* callback.
	* In earlier versions of this app and popular literature it had been shown that onPause is good
	* place to persist any unsaved work, however, this is not really a good practice because of how
	* application and process lifecycle behave.
	* As a general guideline apps should have a way of saving their business logic that does not
	* solely rely on Activity (or other component) lifecyle state transitions.
	* As a backstop you should save any app state, not saved during lifetime of the Activity, in
	* onStop().
	* For a more detailed explanation of this recommendation please read
	* <a href = "https://developer.android.com/guide/topics/processes/process-lifecycle.html">
	* Processes and Application Life Cycle </a>.
	* <a href="https://developer.android.com/training/basics/activity-lifecycle/pausing.html">
	* Pausing and Resuming an Activity </a>.
	*/
	@Override
	protected void onPause() {
	super.onPause();
	}

	/**
	* This method is called when the Activity becomes invisible.
	*
	* For Activity objects that edit information, onStop() may be the one place where changes maybe
	* saved.
	*
	* If the user hasn't done anything, then this deletes or clears out the note, otherwise it
	* writes the user's work to the provider.
	*/
	@Override
	protected void onStop() {
	super.onStop();

	// Get the current note text.
	String text = mText.getText().toString();
	int length = text.length();

	/*
	* If the Activity is in the midst of finishing and there is no text in the current
	* note, returns a result of CANCELED to the caller, and deletes the note. This is done
	* even if the note was being edited, the assumption being that the user wanted to
	* "clear out" (delete) the note.
	*/
	if (isFinishing() && (length == 0)) {
	setResult(RESULT_CANCELED);
	deleteNote();

	/*
	* Writes the edits to the provider. The note has been edited if an existing note
	* was retrieved into the editor or if a new note was inserted.
	* In the latter case, onCreate() inserted a new empty note into the provider,
	* and it is this new note that is being edited.
	*/
	} else if (mState == STATE_EDIT) {
	// Creates a map to contain the new values for the columns
	updateNote(text, null);
	} else if (mState == STATE_INSERT) {
	updateNote(text, text);
	mState = STATE_EDIT;
	}
	}

	/**
	* This method is called when the user clicks the device's Menu button the first time for
	* this Activity. Android passes in a Menu object that is populated with items.
	*
	* Builds the menus for editing and inserting, and adds in alternative actions that
	* registered themselves to handle the MIME types for this application.
	*
	* @param menu A Menu object to which items should be added.
	* @return True to display the menu.
	*/
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
	// Inflate menu from XML resource
	MenuInflater inflater = getMenuInflater();
	inflater.inflate(R.menu.editor_options_menu, menu);

	// Only add extra menu items for a saved note
	if (mState == STATE_EDIT) {
	// Append to the
	// menu items for any other activities that can do stuff with it
	// as well. This does a query on the system for any activities that
	// implement the ALTERNATIVE_ACTION for our data, adding a menu item
	// for each one that is found.
	Intent intent = new Intent(null, mUri);
	intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
	menu.addIntentOptions(Menu.CATEGORY_ALTERNATIVE, 0, 0,
	new ComponentName(this, NoteEditor.class), null, intent, 0, null);
	}

	return super.onCreateOptionsMenu(menu);
	}

	@Override
	public boolean onPrepareOptionsMenu(Menu menu) {
	// Check if note has changed and enable/disable the revert option
	Cursor cursor = getContentResolver().query(
	mUri, // The URI for the note that is to be retrieved.
	PROJECTION, // The columns to retrieve
	null, // No selection criteria are used, so no where columns are needed.
	null, // No where columns are used, so no where values are needed.
	null // No sort order is needed.
	);
	cursor.moveToFirst();
	int colNoteIndex = cursor.getColumnIndex(Notes.COLUMN_NAME_NOTE);
	String savedNote = cursor.getString(colNoteIndex);
	String currentNote = mText.getText().toString();
	if (savedNote.equals(currentNote)) {
	menu.findItem(R.id.menu_revert).setVisible(false);
	} else {
	menu.findItem(R.id.menu_revert).setVisible(true);
	}
	return super.onPrepareOptionsMenu(menu);
	}

	/**
	* This method is called when a menu item is selected. Android passes in the selected item.
	* The switch statement in this method calls the appropriate method to perform the action the
	* user chose.
	*
	* @param item The selected MenuItem
	* @return True to indicate that the item was processed, and no further work is necessary. False
	* to proceed to further processing as indicated in the MenuItem object.
	*/
	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
	// Handle all of the possible menu actions.
	switch (item.getItemId()) {
	case R.id.menu_save:
	String text = mText.getText().toString();
	updateNote(text, null);
	finish();
	break;
	case R.id.menu_delete:
	deleteNote();
	finish();
	break;
	case R.id.menu_revert:
	cancelNote();
	break;
	}
	return super.onOptionsItemSelected(item);
	}

	//BEGIN_INCLUDE(paste)
	/**
	* A helper method that replaces the note's data with the contents of the clipboard.
	*/
	private final void performPaste() {

	// Gets a handle to the Clipboard Manager
	ClipboardManager clipboard = (ClipboardManager)
	getSystemService(Context.CLIPBOARD_SERVICE);

	// Gets a content resolver instance
	ContentResolver cr = getContentResolver();

	// Gets the clipboard data from the clipboard
	ClipData clip = clipboard.getPrimaryClip();
	if (clip != null) {

	String text=null;
	String title=null;

	// Gets the first item from the clipboard data
	ClipData.Item item = clip.getItemAt(0);

	// Tries to get the item's contents as a URI pointing to a note
	Uri uri = item.getUri();

	// Tests to see that the item actually is an URI, and that the URI
	// is a content URI pointing to a provider whose MIME type is the same
	// as the MIME type supported by the Note pad provider.
	if (uri != null && NotePad.Notes.CONTENT_ITEM_TYPE.equals(cr.getType(uri))) {

	// The clipboard holds a reference to data with a note MIME type. This copies it.
	Cursor orig = cr.query(
	uri, // URI for the content provider
	PROJECTION, // Get the columns referred to in the projection
	null, // No selection variables
	null, // No selection variables, so no criteria are needed
	null // Use the default sort order
	);

	// If the Cursor is not null, and it contains at least one record
	// (moveToFirst() returns true), then this gets the note data from it.
	if (orig != null) {
	if (orig.moveToFirst()) {
	int colNoteIndex = orig.getColumnIndex(NotePad.Notes.COLUMN_NAME_NOTE);
	int colTitleIndex = orig.getColumnIndex(NotePad.Notes.COLUMN_NAME_TITLE);
	text = orig.getString(colNoteIndex);
	title = orig.getString(colTitleIndex);
	}

	// Closes the cursor.
	orig.close();
	}
	}

	// If the contents of the clipboard wasn't a reference to a note, then
	// this converts whatever it is to text.
	if (text == null) {
	text = item.coerceToText(this).toString();
	}

	// Updates the current note with the retrieved title and text.
	updateNote(text, title);
	}
	}
	//END_INCLUDE(paste)

	/**
	* Replaces the current note contents with the text and title provided as arguments.
	* @param text The new note contents to use.
	* @param title The new note title to use
	*/
	private final void updateNote(String text, String title) {

	// Sets up a map to contain values to be updated in the provider.
	ContentValues values = new ContentValues();
	values.put(NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE, System.currentTimeMillis());

	// If the action is to insert a new note, this creates an initial title for it.
	if (mState == STATE_INSERT) {

	// If no title was provided as an argument, create one from the note text.
	if (title == null) {

	// Get the note's length
	int length = text.length();

	// Sets the title by getting a substring of the text that is 31 characters long
	// or the number of characters in the note plus one, whichever is smaller.
	title = text.substring(0, Math.min(30, length));

	// If the resulting length is more than 30 characters, chops off any
	// trailing spaces
	if (length > 30) {
	int lastSpace = title.lastIndexOf(' ');
	if (lastSpace > 0) {
	title = title.substring(0, lastSpace);
	}
	}
	}
	// In the values map, sets the value of the title
	values.put(NotePad.Notes.COLUMN_NAME_TITLE, title);
	} else if (title != null) {
	// In the values map, sets the value of the title
	values.put(NotePad.Notes.COLUMN_NAME_TITLE, title);
	}

	// This puts the desired notes text into the map.
	values.put(NotePad.Notes.COLUMN_NAME_NOTE, text);

	/*
	* Updates the provider with the new values in the map. The ListView is updated
	* automatically. The provider sets this up by setting the notification URI for
	* query Cursor objects to the incoming URI. The content resolver is thus
	* automatically notified when the Cursor for the URI changes, and the UI is
	* updated.
	* Note: This is being done on the UI thread. It will block the thread until the
	* update completes. In a sample app, going against a simple provider based on a
	* local database, the block will be momentary, but in a real app you should use
	* android.content.AsyncQueryHandler or android.os.AsyncTask.
	*/
	getContentResolver().update(
	mUri, // The URI for the record to update.
	values, // The map of column names and new values to apply to them.
	null, // No selection criteria are used, so no where columns are necessary.
	null // No where columns are used, so no where arguments are necessary.
	);
	}

	/**
	* This helper method cancels the work done on a note. It deletes the note if it was
	* newly created, or reverts to the original text of the note i
	*/
	private final void cancelNote() {

	if (mState == STATE_EDIT) {
	// Put the original note text back into the database
	ContentValues values = new ContentValues();
	values.put(NotePad.Notes.COLUMN_NAME_NOTE, mOriginalContent);
	getContentResolver().update(mUri, values, null, null);
	} else if (mState == STATE_INSERT) {
	// We inserted an empty note, make sure to delete it
	deleteNote();
	}

	setResult(RESULT_CANCELED);
	finish();
	}

	/**
	* Take care of deleting a note. Simply deletes the entry.
	*/
	private final void deleteNote() {
	getContentResolver().delete(mUri, null, null);
	mText.setText("");
	}

	// LoaderManager callbacks
	@Override
	public Loader<Cursor> onCreateLoader(int i, Bundle bundle) {
	return new CursorLoader(
	this,
	mUri, // The URI for the note that is to be retrieved.
	PROJECTION, // The columns to retrieve
	null, // No selection criteria are used, so no where columns are needed.
	null, // No where columns are used, so no where values are needed.
	null // No sort order is needed.
	);
	}

	@Override
	public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) {

	// Modifies the window title for the Activity according to the current Activity state.
	if (cursor != null && cursor.moveToFirst() && mState == STATE_EDIT) {
	// Set the title of the Activity to include the note title
	int colTitleIndex = cursor.getColumnIndex(NotePad.Notes.COLUMN_NAME_TITLE);
	int colNoteIndex = cursor.getColumnIndex(NotePad.Notes.COLUMN_NAME_NOTE);

	// Gets the title and sets it
	String title = cursor.getString(colTitleIndex);
	Resources res = getResources();
	String text = String.format(res.getString(R.string.title_edit), title);
	setTitle(text);

	// Gets the note text from the Cursor and puts it in the TextView, but doesn't change
	// the text cursor's position.

	String note = cursor.getString(colNoteIndex);
	mText.setTextKeepState(note);
	// Stores the original note text, to allow the user to revert changes.
	if (mOriginalContent == null) {
	mOriginalContent = note;
	}
	}
	}

	@Override
	public void onLoaderReset(Loader<Cursor> cursorLoader) {}
	}