path: root/android/src/com/artifex/mupdfdemo/MuPDFActivity.java

package com.artifex.mupdfdemo;

import java.io.InputStream;
import java.util.concurrent.Executor;

import android.animation.Animator;
import android.animation.AnimatorInflater;
import android.animation.AnimatorSet;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.database.Cursor;
import android.graphics.Color;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.text.Editable;
import android.text.TextWatcher;
import android.text.method.PasswordTransformationMethod;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.TranslateAnimation;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.RelativeLayout;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.ViewAnimator;

class ThreadPerTaskExecutor implements Executor {
	public void execute(Runnable r) {
		new Thread(r).start();
	}
}

public class MuPDFActivity extends Activity
{
	/* The core rendering instance */
	enum TopBarMode {Main, Search, Text, Annotation};

	private MuPDFCore    core;
	private String       mFileName;
	private MuPDFReaderView mDocView;
	private View         mButtonsView;
	private boolean      mButtonsVisible;
	private EditText     mPasswordView;
	private TextView     mFilenameView;
	private SeekBar      mPageSlider;
	private int          mPageSliderRes;
	private TextView     mPageNumberView;
	private TextView     mInfoView;
	private ImageButton  mSearchButton;
	private ImageButton  mReflowButton;
	private ImageButton mSelectButton;
	private ImageButton mCancelSelectButton;
	private ImageButton mCopySelectButton;
	private ImageButton mHighlightButton;
	private ImageButton mUnderlineButton;
	private ImageButton mStrikeOutButton;
	private ImageButton  mCancelButton;
	private ImageButton  mOutlineButton;
	private ImageButton  mDeleteButton;
	private ViewAnimator mTopBarSwitcher;
	private ImageButton  mLinkButton;
	private TopBarMode   mTopBarMode;
	private ImageButton  mSearchBack;
	private ImageButton  mSearchFwd;
	private EditText     mSearchText;
	private SearchTask   mSearchTask;
	private AlertDialog.Builder mAlertBuilder;
	private boolean    mLinkHighlight = false;
	private final Handler mHandler = new Handler();
	private boolean mAlertsActive= false;
	private boolean mReflow = false;
	private AsyncTask<Void,Void,MuPDFAlert> mAlertTask;
	private AlertDialog mAlertDialog;

	public void createAlertWaiter() {
		mAlertsActive = true;
		// All mupdf library calls are performed on asynchronous tasks to avoid stalling
		// the UI. Some calls can lead to javascript-invoked requests to display an
		// alert dialog and collect a reply from the user. The task has to be blocked
		// until the user's reply is received. This method creates an asynchronous task,
		// the purpose of which is to wait of these requests and produce the dialog
		// in response, while leaving the core blocked. When the dialog receives the
		// user's response, it is sent to the core via replyToAlert, unblocking it.
		// Another alert-waiting task is then created to pick up the next alert.
		if (mAlertTask != null) {
			mAlertTask.cancel(true);
			mAlertTask = null;
		}
		if (mAlertDialog != null) {
			mAlertDialog.cancel();
			mAlertDialog = null;
		}
		mAlertTask = new AsyncTask<Void,Void,MuPDFAlert>() {

			@Override
			protected MuPDFAlert doInBackground(Void... arg0) {
				if (!mAlertsActive)
					return null;

				return core.waitForAlert();
			}

			@Override
			protected void onPostExecute(final MuPDFAlert result) {
				// core.waitForAlert may return null when shutting down
				if (result == null)
					return;
				final MuPDFAlert.ButtonPressed pressed[] = new MuPDFAlert.ButtonPressed[3];
				for(int i = 0; i < 3; i++)
					pressed[i] = MuPDFAlert.ButtonPressed.None;
				DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
					public void onClick(DialogInterface dialog, int which) {
						mAlertDialog = null;
						if (mAlertsActive) {
							int index = 0;
							switch (which) {
							case AlertDialog.BUTTON1: index=0; break;
							case AlertDialog.BUTTON2: index=1; break;
							case AlertDialog.BUTTON3: index=2; break;
							}
							result.buttonPressed = pressed[index];
							// Send the user's response to the core, so that it can
							// continue processing.
							core.replyToAlert(result);
							// Create another alert-waiter to pick up the next alert.
							createAlertWaiter();
						}
					}
				};
				mAlertDialog = mAlertBuilder.create();
				mAlertDialog.setTitle(result.title);
				mAlertDialog.setMessage(result.message);
				switch (result.iconType)
				{
				case Error:
					break;
				case Warning:
					break;
				case Question:
					break;
				case Status:
					break;
				}
				switch (result.buttonGroupType)
				{
				case OkCancel:
					mAlertDialog.setButton(AlertDialog.BUTTON2, "Cancel", listener);
					pressed[1] = MuPDFAlert.ButtonPressed.Cancel;
				case Ok:
					mAlertDialog.setButton(AlertDialog.BUTTON1, "Ok", listener);
					pressed[0] = MuPDFAlert.ButtonPressed.Ok;
					break;
				case YesNoCancel:
					mAlertDialog.setButton(AlertDialog.BUTTON3, "Cancel", listener);
					pressed[2] = MuPDFAlert.ButtonPressed.Cancel;
				case YesNo:
					mAlertDialog.setButton(AlertDialog.BUTTON1, "Yes", listener);
					pressed[0] = MuPDFAlert.ButtonPressed.Yes;
					mAlertDialog.setButton(AlertDialog.BUTTON2, "No", listener);
					pressed[1] = MuPDFAlert.ButtonPressed.No;
					break;
				}
				mAlertDialog.setOnCancelListener(new DialogInterface.OnCancelListener() {
					public void onCancel(DialogInterface dialog) {
						mAlertDialog = null;
						if (mAlertsActive) {
							result.buttonPressed = MuPDFAlert.ButtonPressed.None;
							core.replyToAlert(result);
							createAlertWaiter();
						}
					}
				});

				mAlertDialog.show();
			}
		};

		mAlertTask.executeOnExecutor(new ThreadPerTaskExecutor());
	}

	public void destroyAlertWaiter() {
		mAlertsActive = false;
		if (mAlertDialog != null) {
			mAlertDialog.cancel();
			mAlertDialog = null;
		}
		if (mAlertTask != null) {
			mAlertTask.cancel(true);
			mAlertTask = null;
		}
	}

	private MuPDFCore openFile(String path)
	{
		int lastSlashPos = path.lastIndexOf('/');
		mFileName = new String(lastSlashPos == -1
					? path
					: path.substring(lastSlashPos+1));
		System.out.println("Trying to open "+path);
		try
		{
			core = new MuPDFCore(path);
			// New file: drop the old outline data
			OutlineActivityData.set(null);
		}
		catch (Exception e)
		{
			System.out.println(e);
			return null;
		}
		return core;
	}

	private MuPDFCore openBuffer(byte buffer[])
	{
		System.out.println("Trying to open byte buffer");
		try
		{
			core = new MuPDFCore(buffer);
			// New file: drop the old outline data
			OutlineActivityData.set(null);
		}
		catch (Exception e)
		{
			System.out.println(e);
			return null;
		}
		return core;
	}

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);


		mAlertBuilder = new AlertDialog.Builder(this);

		if (core == null) {
			core = (MuPDFCore)getLastNonConfigurationInstance();

			if (savedInstanceState != null && savedInstanceState.containsKey("FileName")) {
				mFileName = savedInstanceState.getString("FileName");
			}
		}
		if (core == null) {
			Intent intent = getIntent();
			byte buffer[] = null;
			if (Intent.ACTION_VIEW.equals(intent.getAction())) {
				Uri uri = intent.getData();
				if (uri.toString().startsWith("content://")) {
					// Handle view requests from the Transformer Prime's file manager
					// Hopefully other file managers will use this same scheme, if not
					// using explicit paths.
					Cursor cursor = getContentResolver().query(uri, new String[]{"_data"}, null, null, null);
					if (cursor.moveToFirst()) {
						String str = cursor.getString(0);
						String failString = null;
						if (str == null) {
							try {
								InputStream is = getContentResolver().openInputStream(uri);
								int len = is.available();
								buffer = new byte[len];
								is.read(buffer, 0, len);
								is.close();
							}
							catch (java.lang.OutOfMemoryError e)
							{
								System.out.println("Out of memory during buffer reading");
								failString = e.toString();
							}
							catch (Exception e) {
								failString = e.toString();
							}
							if (failString != null)
							{
								buffer = null;
								Resources res = getResources();
								AlertDialog alert = mAlertBuilder.create();
								String contentFailure = res.getString(R.string.content_failure);
								String openFailed = res.getString(R.string.open_failed);
								setTitle(String.format(contentFailure, openFailed, failString));
								alert.setButton(AlertDialog.BUTTON_POSITIVE, "Dismiss",
										new DialogInterface.OnClickListener() {
											public void onClick(DialogInterface dialog, int which) {
												finish();
											}
										});
								alert.show();
								return;
							}
						} else {
							uri = Uri.parse(str);
						}
					}
				}
				if (buffer != null) {
					core = openBuffer(buffer);
				} else {
					core = openFile(Uri.decode(uri.getEncodedPath()));
				}
				SearchTaskResult.set(null);
				if (core.countPages() == 0)
					core = null;
			}
			if (core != null && core.needsPassword()) {
				requestPassword(savedInstanceState);
				return;
			}
		}
		if (core == null)
		{
			AlertDialog alert = mAlertBuilder.create();
			alert.setTitle(R.string.open_failed);
			alert.setButton(AlertDialog.BUTTON_POSITIVE, "Dismiss",
					new DialogInterface.OnClickListener() {
						public void onClick(DialogInterface dialog, int which) {
							finish();
						}
					});
			alert.show();
			return;
		}

		createUI(savedInstanceState);
	}

	public void requestPassword(final Bundle savedInstanceState) {
		mPasswordView = new EditText(this);
		mPasswordView.setInputType(EditorInfo.TYPE_TEXT_VARIATION_PASSWORD);
		mPasswordView.setTransformationMethod(new PasswordTransformationMethod());

		AlertDialog alert = mAlertBuilder.create();
		alert.setTitle(R.string.enter_password);
		alert.setView(mPasswordView);
		alert.setButton(AlertDialog.BUTTON_POSITIVE, "Ok",
				new DialogInterface.OnClickListener() {
			public void onClick(DialogInterface dialog, int which) {
				if (core.authenticatePassword(mPasswordView.getText().toString())) {
					createUI(savedInstanceState);
				} else {
					requestPassword(savedInstanceState);
				}
			}
		});
		alert.setButton(AlertDialog.BUTTON_NEGATIVE, "Cancel",
				new DialogInterface.OnClickListener() {

			public void onClick(DialogInterface dialog, int which) {
				finish();
			}
		});
		alert.show();
	}

	public void createUI(Bundle savedInstanceState) {
		if (core == null)
			return;

		// Now create the UI.
		// First create the document view
		mDocView = new MuPDFReaderView(this) {
			@Override
			protected void onMoveToChild(int i) {
				if (core == null)
					return;
				mPageNumberView.setText(String.format("%d / %d", i + 1,
						core.countPages()));
				mPageSlider.setMax((core.countPages() - 1) * mPageSliderRes);
				mPageSlider.setProgress(i * mPageSliderRes);
				super.onMoveToChild(i);
			}

			@Override
			protected void onTapMainDocArea() {
				if (!mButtonsVisible) {
					showButtons();
				} else {
					hideButtons();
				}
			}

			@Override
			protected void onDocMotion() {
				hideButtons();
			}

			@Override
			protected void onHit(Hit item) {
				switch (item) {
				case Annotation:
					showButtons();
					mTopBarMode = TopBarMode.Annotation;
					mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
					break;
				case Widget:
				case Nothing:
					if (mTopBarMode == TopBarMode.Annotation) {
						mTopBarMode = TopBarMode.Main;
						mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
					}
					break;
				}
			}
		};
		mDocView.setAdapter(new MuPDFPageAdapter(this, core));

		mSearchTask = new SearchTask(this, core) {
			@Override
			protected void onTextFound(SearchTaskResult result) {
				SearchTaskResult.set(result);
				// Ask the ReaderView to move to the resulting page
				mDocView.setDisplayedViewIndex(result.pageNumber);
				// Make the ReaderView act on the change to SearchTaskResult
				// via overridden onChildSetup method.
				mDocView.resetupChildren();
			}
		};

		// Make the buttons overlay, and store all its
		// controls in variables
		makeButtonsView();

		// Set up the page slider
		int smax = Math.max(core.countPages()-1,1);
		mPageSliderRes = ((10 + smax - 1)/smax) * 2;

		// Set the file-name text
		mFilenameView.setText(mFileName);

		// Activate the seekbar
		mPageSlider.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
			public void onStopTrackingTouch(SeekBar seekBar) {
				mDocView.setDisplayedViewIndex((seekBar.getProgress()+mPageSliderRes/2)/mPageSliderRes);
			}

			public void onStartTrackingTouch(SeekBar seekBar) {}

			public void onProgressChanged(SeekBar seekBar, int progress,
					boolean fromUser) {
				updatePageNumView((progress+mPageSliderRes/2)/mPageSliderRes);
			}
		});

		// Activate the search-preparing button
		mSearchButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				searchModeOn();
			}
		});

		// Activate the reflow button
		mReflowButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				toggleReflow();
			}
		});

		// Activate the select button
		mSelectButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				mDocView.setMode(MuPDFReaderView.Mode.Selecting);
				mTopBarMode = TopBarMode.Text;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
			}
		});

		mCancelSelectButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				MuPDFView pageView = (MuPDFView) mDocView.getDisplayedView();
				if (pageView != null)
					pageView.deselectText();
				mDocView.setMode(MuPDFReaderView.Mode.Viewing);
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
			}
		});

		mCopySelectButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				MuPDFView pageView = (MuPDFView) mDocView.getDisplayedView();
				boolean copied = false;
				if (pageView != null)
					copied = pageView.copySelection();
				mDocView.setMode(MuPDFReaderView.Mode.Viewing);
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
				showInfo(copied?"Copied to clipboard":"No text selected");
			}
		});

		mHighlightButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				MuPDFView pageView = (MuPDFView) mDocView.getDisplayedView();
				boolean success = false;
				if (pageView != null)
					success = pageView.markupSelection(Annotation.Type.HIGHLIGHT);
				mDocView.setMode(MuPDFReaderView.Mode.Viewing);
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
				if (!success)
					showInfo("No text selected");
			}
		});

		mUnderlineButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				MuPDFView pageView = (MuPDFView) mDocView.getDisplayedView();
				boolean success = false;
				if (pageView != null)
					success = pageView.markupSelection(Annotation.Type.UNDERLINE);
				mDocView.setMode(MuPDFReaderView.Mode.Viewing);
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
				if (!success)
					showInfo("No text selected");
			}
		});

		mStrikeOutButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				MuPDFView pageView = (MuPDFView) mDocView.getDisplayedView();
				boolean success = false;
				if (pageView != null)
					success = pageView.markupSelection(Annotation.Type.STRIKEOUT);
				mDocView.setMode(MuPDFReaderView.Mode.Viewing);
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
				if (!success)
					showInfo("No text selected");
			}
		});

		mCancelButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				searchModeOff();
			}
		});

		// Search invoking buttons are disabled while there is no text specified
		mSearchBack.setEnabled(false);
		mSearchFwd.setEnabled(false);
		mSearchBack.setColorFilter(Color.argb(255, 128, 128, 128));
		mSearchFwd.setColorFilter(Color.argb(255, 128, 128, 128));

		// React to interaction with the text widget
		mSearchText.addTextChangedListener(new TextWatcher() {

			public void afterTextChanged(Editable s) {
				boolean haveText = s.toString().length() > 0;
				mSearchBack.setEnabled(haveText);
				mSearchFwd.setEnabled(haveText);
				if (haveText) {
					mSearchBack.setColorFilter(Color.argb(255, 255, 255, 255));
					mSearchFwd.setColorFilter(Color.argb(255, 255, 255, 255));
				} else {
					mSearchBack.setColorFilter(Color.argb(255, 128, 128, 128));
					mSearchFwd.setColorFilter(Color.argb(255, 128, 128, 128));
				}

				// Remove any previous search results
				if (SearchTaskResult.get() != null && !mSearchText.getText().toString().equals(SearchTaskResult.get().txt)) {
					SearchTaskResult.set(null);
					mDocView.resetupChildren();
				}
			}
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {}
			public void onTextChanged(CharSequence s, int start, int before,
					int count) {}
		});

		//React to Done button on keyboard
		mSearchText.setOnEditorActionListener(new TextView.OnEditorActionListener() {
			public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
				if (actionId == EditorInfo.IME_ACTION_DONE)
					search(1);
				return false;
			}
		});

		mSearchText.setOnKeyListener(new View.OnKeyListener() {
			public boolean onKey(View v, int keyCode, KeyEvent event) {
				if (event.getAction() == KeyEvent.ACTION_DOWN && keyCode == KeyEvent.KEYCODE_ENTER)
					search(1);
				return false;
			}
		});

		// Activate search invoking buttons
		mSearchBack.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				search(-1);
			}
		});
		mSearchFwd.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				search(1);
			}
		});

		mLinkButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				if (mLinkHighlight) {
					mLinkButton.setColorFilter(Color.argb(0xFF, 255, 255, 255));
					mLinkHighlight = false;
				} else {
					// LINK_COLOR tint
					mLinkButton.setColorFilter(Color.argb(0xFF, 172, 114, 37));
					mLinkHighlight = true;
				}
				// Inform pages of the change.
				mDocView.setLinksEnabled(mLinkHighlight);
			}
		});

		if (core.hasOutline()) {
			mOutlineButton.setOnClickListener(new View.OnClickListener() {
				public void onClick(View v) {
					OutlineItem outline[] = core.getOutline();
					if (outline != null) {
						OutlineActivityData.get().items = outline;
						Intent intent = new Intent(MuPDFActivity.this, OutlineActivity.class);
						startActivityForResult(intent, 0);
					}
				}
			});
		} else {
			mOutlineButton.setVisibility(View.GONE);
		}

		mDeleteButton.setOnClickListener(new View.OnClickListener() {
			public void onClick(View v) {
				View cv = mDocView.getDisplayedView();
				if (cv != null)
					((MuPDFView)cv).deleteSelectedAnnotation();
				mTopBarMode = TopBarMode.Main;
				mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
			}
		});

		// Reenstate last state if it was recorded
		SharedPreferences prefs = getPreferences(Context.MODE_PRIVATE);
		mDocView.setDisplayedViewIndex(prefs.getInt("page"+mFileName, 0));

		if (savedInstanceState == null || !savedInstanceState.getBoolean("ButtonsHidden", false))
			showButtons();

		if(savedInstanceState != null && savedInstanceState.getBoolean("SearchMode", false))
			searchModeOn();

		// Stick the document view and the buttons overlay into a parent view
		RelativeLayout layout = new RelativeLayout(this);
		layout.addView(mDocView);
		layout.addView(mButtonsView);
		layout.setBackgroundResource(R.drawable.tiled_background);
		//layout.setBackgroundResource(R.color.canvas);
		setContentView(layout);
	}

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		if (resultCode >= 0)
			mDocView.setDisplayedViewIndex(resultCode);
		super.onActivityResult(requestCode, resultCode, data);
	}

	public Object onRetainNonConfigurationInstance()
	{
		MuPDFCore mycore = core;
		core = null;
		return mycore;
	}

	private void toggleReflow() {
		mReflow = !mReflow;
		if (mReflow) {
			mDocView.setAdapter(new MuPDFReflowAdapter(this, core));
			mReflowButton.setColorFilter(Color.argb(0xFF, 172, 114, 37));
		} else {
			mDocView.setAdapter(new MuPDFPageAdapter(this, core));
			mReflowButton.setColorFilter(Color.argb(0xFF, 255, 255, 255));
		}
		mDocView.refresh(mReflow);
	}

	@Override
	protected void onSaveInstanceState(Bundle outState) {
		super.onSaveInstanceState(outState);

		if (mFileName != null && mDocView != null) {
			outState.putString("FileName", mFileName);

			// Store current page in the prefs against the file name,
			// so that we can pick it up each time the file is loaded
			// Other info is needed only for screen-orientation change,
			// so it can go in the bundle
			SharedPreferences prefs = getPreferences(Context.MODE_PRIVATE);
			SharedPreferences.Editor edit = prefs.edit();
			edit.putInt("page"+mFileName, mDocView.getDisplayedViewIndex());
			edit.commit();
		}

		if (!mButtonsVisible)
			outState.putBoolean("ButtonsHidden", true);

		if (mTopBarMode == TopBarMode.Search)
			outState.putBoolean("SearchMode", true);
	}

	@Override
	protected void onPause() {
		super.onPause();

		if (mSearchTask != null)
			mSearchTask.stop();

		if (mFileName != null && mDocView != null) {
			SharedPreferences prefs = getPreferences(Context.MODE_PRIVATE);
			SharedPreferences.Editor edit = prefs.edit();
			edit.putInt("page"+mFileName, mDocView.getDisplayedViewIndex());
			edit.commit();
		}
	}

	public void onDestroy()
	{
		if (core != null)
			core.onDestroy();
		if (mAlertTask != null) {
			mAlertTask.cancel(true);
			mAlertTask = null;
		}
		core = null;
		super.onDestroy();
	}

	void showButtons() {
		if (core == null)
			return;
		if (!mButtonsVisible) {
			mButtonsVisible = true;
			// Update page number text and slider
			int index = mDocView.getDisplayedViewIndex();
			updatePageNumView(index);
			mPageSlider.setMax((core.countPages()-1)*mPageSliderRes);
			mPageSlider.setProgress(index*mPageSliderRes);
			if (mTopBarMode == TopBarMode.Search) {
				mSearchText.requestFocus();
				showKeyboard();
			}

			Animation anim = new TranslateAnimation(0, 0, -mTopBarSwitcher.getHeight(), 0);
			anim.setDuration(200);
			anim.setAnimationListener(new Animation.AnimationListener() {
				public void onAnimationStart(Animation animation) {
					mTopBarSwitcher.setVisibility(View.VISIBLE);
				}
				public void onAnimationRepeat(Animation animation) {}
				public void onAnimationEnd(Animation animation) {}
			});
			mTopBarSwitcher.startAnimation(anim);

			anim = new TranslateAnimation(0, 0, mPageSlider.getHeight(), 0);
			anim.setDuration(200);
			anim.setAnimationListener(new Animation.AnimationListener() {
				public void onAnimationStart(Animation animation) {
					mPageSlider.setVisibility(View.VISIBLE);
				}
				public void onAnimationRepeat(Animation animation) {}
				public void onAnimationEnd(Animation animation) {
					mPageNumberView.setVisibility(View.VISIBLE);
				}
			});
			mPageSlider.startAnimation(anim);
		}
	}

	void hideButtons() {
		if (mButtonsVisible) {
			mButtonsVisible = false;
			hideKeyboard();

			Animation anim = new TranslateAnimation(0, 0, 0, -mTopBarSwitcher.getHeight());
			anim.setDuration(200);
			anim.setAnimationListener(new Animation.AnimationListener() {
				public void onAnimationStart(Animation animation) {}
				public void onAnimationRepeat(Animation animation) {}
				public void onAnimationEnd(Animation animation) {
					mTopBarSwitcher.setVisibility(View.INVISIBLE);
				}
			});
			mTopBarSwitcher.startAnimation(anim);

			anim = new TranslateAnimation(0, 0, 0, mPageSlider.getHeight());
			anim.setDuration(200);
			anim.setAnimationListener(new Animation.AnimationListener() {
				public void onAnimationStart(Animation animation) {
					mPageNumberView.setVisibility(View.INVISIBLE);
				}
				public void onAnimationRepeat(Animation animation) {}
				public void onAnimationEnd(Animation animation) {
					mPageSlider.setVisibility(View.INVISIBLE);
				}
			});
			mPageSlider.startAnimation(anim);
		}
	}

	void searchModeOn() {
		if (mTopBarMode != TopBarMode.Search) {
			mTopBarMode = TopBarMode.Search;
			//Focus on EditTextWidget
			mSearchText.requestFocus();
			showKeyboard();
			mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
		}
	}

	void searchModeOff() {
		if (mTopBarMode == TopBarMode.Search) {
			mTopBarMode = TopBarMode.Main;
			hideKeyboard();
			mTopBarSwitcher.setDisplayedChild(mTopBarMode.ordinal());
			SearchTaskResult.set(null);
			// Make the ReaderView act on the change to mSearchTaskResult
			// via overridden onChildSetup method.
			mDocView.resetupChildren();
		}
	}

	void updatePageNumView(int index) {
		if (core == null)
			return;
		mPageNumberView.setText(String.format("%d / %d", index+1, core.countPages()));
	}

	private void showInfo(String message) {
		mInfoView.setText(message);

		int currentApiVersion = android.os.Build.VERSION.SDK_INT;
		if (currentApiVersion >= android.os.Build.VERSION_CODES.HONEYCOMB) {
			AnimatorSet set = (AnimatorSet) AnimatorInflater.loadAnimator(this, R.animator.info);
			set.setTarget(mInfoView);
			set.addListener(new Animator.AnimatorListener() {
				public void onAnimationStart(Animator animation) {
					mInfoView.setVisibility(View.VISIBLE);
				}

				public void onAnimationRepeat(Animator animation) {
				}

				public void onAnimationEnd(Animator animation) {
					mInfoView.setVisibility(View.INVISIBLE);
				}

				public void onAnimationCancel(Animator animation) {
				}
			});
			set.start();
		} else {
			mInfoView.setVisibility(View.VISIBLE);
			mHandler.postDelayed(new Runnable() {
				public void run() {
					mInfoView.setVisibility(View.INVISIBLE);
				}
			}, 500);
		}
	}

	void makeButtonsView() {
		mButtonsView = getLayoutInflater().inflate(R.layout.buttons,null);
		mFilenameView = (TextView)mButtonsView.findViewById(R.id.docNameText);
		mPageSlider = (SeekBar)mButtonsView.findViewById(R.id.pageSlider);
		mPageNumberView = (TextView)mButtonsView.findViewById(R.id.pageNumber);
		mInfoView = (TextView)mButtonsView.findViewById(R.id.info);
		mSearchButton = (ImageButton)mButtonsView.findViewById(R.id.searchButton);
		mReflowButton = (ImageButton)mButtonsView.findViewById(R.id.reflowButton);
		mSelectButton = (ImageButton)mButtonsView.findViewById(R.id.selectButton);
		mCancelSelectButton = (ImageButton)mButtonsView.findViewById(R.id.cancelSelectButton);
		mCopySelectButton = (ImageButton)mButtonsView.findViewById(R.id.copySelectButton);
		mHighlightButton = (ImageButton)mButtonsView.findViewById(R.id.highlightButton);
		mUnderlineButton = (ImageButton)mButtonsView.findViewById(R.id.underlineButton);
		mStrikeOutButton = (ImageButton)mButtonsView.findViewById(R.id.strikeOutButton);
		mCancelButton = (ImageButton)mButtonsView.findViewById(R.id.cancel);
		mOutlineButton = (ImageButton)mButtonsView.findViewById(R.id.outlineButton);
		mDeleteButton = (ImageButton)mButtonsView.findViewById(R.id.deleteButton);
		mTopBarSwitcher = (ViewAnimator)mButtonsView.findViewById(R.id.switcher);
		mSearchBack = (ImageButton)mButtonsView.findViewById(R.id.searchBack);
		mSearchFwd = (ImageButton)mButtonsView.findViewById(R.id.searchForward);
		mSearchText = (EditText)mButtonsView.findViewById(R.id.searchText);
		mLinkButton = (ImageButton)mButtonsView.findViewById(R.id.linkButton);
		mTopBarSwitcher.setVisibility(View.INVISIBLE);
		mPageNumberView.setVisibility(View.INVISIBLE);
		mInfoView.setVisibility(View.INVISIBLE);
		mPageSlider.setVisibility(View.INVISIBLE);
	}

	void showKeyboard() {
		InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
		if (imm != null)
			imm.showSoftInput(mSearchText, 0);
	}

	void hideKeyboard() {
		InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
		if (imm != null)
			imm.hideSoftInputFromWindow(mSearchText.getWindowToken(), 0);
	}

	void search(int direction) {
		hideKeyboard();
		int displayPage = mDocView.getDisplayedViewIndex();
		SearchTaskResult r = SearchTaskResult.get();
		int searchPage = r != null ? r.pageNumber : -1;
		mSearchTask.go(mSearchText.getText().toString(), direction, displayPage, searchPage);
	}

	@Override
	public boolean onSearchRequested() {
		if (mButtonsVisible && mTopBarMode == TopBarMode.Search) {
			hideButtons();
		} else {
			showButtons();
			searchModeOn();
		}
		return super.onSearchRequested();
	}

	@Override
	public boolean onPrepareOptionsMenu(Menu menu) {
		if (mButtonsVisible && mTopBarMode != TopBarMode.Search) {
			hideButtons();
		} else {
			showButtons();
			searchModeOff();
		}
		return super.onPrepareOptionsMenu(menu);
	}

	@Override
	protected void onStart() {
		if (core != null)
		{
			core.startAlerts();
			createAlertWaiter();
		}

		super.onStart();
	}

	@Override
	protected void onStop() {
		if (core != null)
		{
			destroyAlertWaiter();
			core.stopAlerts();
		}

		super.onStop();
	}

	@Override
	public void onBackPressed() {
		if (core.hasChanges()) {
			DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
				public void onClick(DialogInterface dialog, int which) {
					if (which == AlertDialog.BUTTON_POSITIVE)
						core.save();

					finish();
				}
			};
			AlertDialog alert = mAlertBuilder.create();
			alert.setTitle("MuPDF");
			alert.setMessage("Document has changes. Save them?");
			alert.setButton(AlertDialog.BUTTON_POSITIVE, "Yes", listener);
			alert.setButton(AlertDialog.BUTTON_NEGATIVE, "No", listener);
			alert.show();
		} else {
			super.onBackPressed();
		}
	}
}