FQG - Source_Code

// FlagQuizGame.java
// mainActivity for the Flag Quiz Game App
package com.deitel.flagquizgame;

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Set;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.res.AssetManager;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;

public class FlagQuizGame extends Activity
{
    // String used when logging error messages
	private static final String TAG = "FlagQuizGame Activity";

	private List<String> fileNameList; // flag file names
	private List<String> quizCountriesList; // names of countries in quiz
	private Map<String, Boolean> regionsMap; //which regions are enabled
	private String correctAnswer; // correct country for the current flag
	private int totalGuesses; // number of guesses made
	private int correctAnswers; // number of correct guesses
	private int guessRows; // number of rows displaying choices
	private Random random; // random number generator
	private Handler handler; // used to delay loading next flag
	private Animation shakeAnimation; // animation for incorrect guess

	private TextView answerTextView; // displays Correct! or Incorrect!
	private TextView questionNumberTextView; // shows current question #
	private ImageView flagImageView; // displays a flag
	private TableLayout buttonTableLayout; // table of answer Buttons

	// called when the activity is first created
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState); // call the superclass's method
        setContentView(R.layout.main); // inflate the GUI

        fileNameList = new ArrayList<String>(); // list of image file names
        quizCountriesList = new ArrayList<String>(); // flags in this quiz
        regionsMap = new HashMap<String, Boolean>(); // HashMap of regions
        guessRows = 1; // default to one row of choices
        random = new Random(); // initialize the random number generator
        handler = new Handler(); // used to perform delayed operations

        // loads the shake animation that's used for incorrect answers
        shakeAnimation = AnimationUtils.loadAnimation(this, R.anim.incorrect_shake);
        shakeAnimation.setRepeatCount(3); // animation repeats 3 times

        // get array of world regions from strings.xml
        String[] regionNames = getResources().getStringArray(R.array.regionsList);

        // by default, countries are chosen from all regions
        for (String region : regionNames)
        	regionsMap.put(region, true);

        // get references to GUI components
        questionNumberTextView = (TextView) findViewById(R.id.questionNumberTextView);
        flagImageView = (ImageView) findViewById(R.id.flagImageView);
        buttonTableLayout = (TableLayout) findViewById(R.id.buttonTableLayout);
        answerTextView = (TextView) findViewById(R.id.answerTextView);

        // set questionNumberTextView's text
        questionNumberTextView.setText(getResources().getString(R.string.question) + "1" + getResources().getString(R.string.of) + "10");

        resetQuiz(); // start a new quiz
    } // end method onCreate

    // set up and start the next quiz
    private void resetQuiz()
    {
    	// use the AssetManager to get the image flag
    	//file names for only the enabled regions
    	AssetManager assets = getAssets(); // get the app's AssetManager
    	fileNameList.clear(); // empty the list

    	try
    	{
    		Set<String> regions = regionsMap.keySet(); // get Set of regions

    		// loop through each region
    		for (String region : regions)
    		{
    			if (regionsMap.get(region)) // if region is enabled
    			{
    				// get a list of all flag image files in this region
    				String[] paths = assets.list(region);

    				for (String path : paths)
    					fileNameList.add(path.replace(".png", ""));
    			} // end if
    		} // end for
    	} // end try

    	catch (IOException e)
    	{
    		Log.e(TAG, "Error loading file image names", e);
    	} // end catch

    	correctAnswers = 0; // reset the number of correct answers made
    	totalGuesses = 0; // reset the total number of guesses the user made
    	quizCountriesList.clear(); // clear prior list of quiz countries

    	// add 10 random file names to the quizCountriesList
    	int flagCounter = 1;
    	int numberOfFlags = fileNameList.size(); // get number of flags

    	while (flagCounter <= 10)

    	{int randomIndex = random.nextInt(numberOfFlags); // random index

    	// get the random file name
    	String fileName = fileNameList.get(randomIndex);

    	// if the region is enabled and it hasn't already been chosen
    	if (!quizCountriesList.contains(fileName))
    	{
    		quizCountriesList.add(fileName); // add the file to the list
    		++flagCounter;
    	} // end if
    } // end while

    loadNextFlag(); // start the quiz by loading the first flag
  } // end method resetQuiz

    // after the user guesses a correct flag, load the next flag
    private void loadNextFlag()
    {
    	// get file name of the next flag and remove it from the list
    	String nextImageName = quizCountriesList.remove(0);
    	correctAnswer = nextImageName; // update the correct answer

    	answerTextView.setText(""); // clear answerTextView

    	// display the number of the current question in the quiz
    	questionNumberTextView.setText(getResources().getString(R.string.question) + "" +
    	(correctAnswers + 1) + "" + getResources().getString(R.string.of) +"10");

    	// extract the region from the next image's name
    	String region = nextImageName.substring(0, nextImageName.indexOf('-'));

    	//use AssetManager to load next image from assets folder
    	AssetManager assets = getAssets(); // get app's AssetManager
    	InputStream stream; // used to read in flag images

    	try
    	{
    		// get an InputStream to the asset representing the next flag
    		stream = assets.open(region + "/" + nextImageName + ".png");

    		// load the asset as a Drawable and display on the flagImageView
    		Drawable flag = Drawable.createFromStream(stream,  nextImageName);
    		flagImageView.setImageDrawable(flag);
    	} // end try
    	catch (IOException e)
    	{
    		Log.e(TAG, "Error loading" + nextImageName, e);
    	} // end catch

    	// clear prior answer Buttons from TableRow
    	for (int row = 0; row < buttonTableLayout.getChildCount(); ++row)
    	((TableRow) buttonTableLayout.getChildAt(row)).removeAllViews();

    	Collections.shuffle(fileNameList); // shuffle file names

    	//put the correct answer at the end of fileNameList
    	int correct = fileNameList.indexOf(correctAnswer);
    	fileNameList.add(fileNameList.remove(correct));

    	// get a reference to the LayoutInflater service
    	LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    	//add 3, 6, or 9 answer Buttons based on the value of guessRows
    	for (int row = 0; row < guessRows; row++)
    	{
    		TableRow currentTableRow = getTableRow(row);

    		//place Buttons in currentTableRow
    		for (int column = 0; column < 3; column++)
    		{
    			// inflate guess_button.xml to create new Button
    			Button newGuessButton = (Button) inflater.inflate(R.layout.guess_button, null);

    			// get country name and set it as newGuessButton's text
    			String fileName = fileNameList.get((row * 3) + column);
    			newGuessButton.setText(getCountryName(fileName));

    			// register answerButtonListener to respond to button clicks
    			newGuessButton.setOnClickListener(guessButtonListener);
    			currentTableRow.addView(newGuessButton);
    		} // end for
    	} // end for

    	// randomly replace one Button with the correct answer
    	int row = random.nextInt(guessRows); // pick random row
    	int column = random.nextInt(3); // pick random column
    	TableRow randomTableRow = getTableRow(row); // get the TableRow
    	String countryName = getCountryName(correctAnswer);
    	((Button)randomTableRow.getChildAt(column)).setText(countryName);
    } // end method loadNextFlag

    // returns the specified TableRow
    private TableRow getTableRow(int row)
    {
    	return (TableRow) buttonTableLayout.getChildAt(row);
    } // end method getTableRow

    //parses the country flag file name and returns the country name
    private String getCountryName(String name)
    {
    	return name.substring(name.indexOf('-') + 1).replace('_', ' ');
    } // end method getCountryName

    // called when the user selects an answer
    private void submitGuess(Button guessButton)
    {
    	String guess = guessButton.getText().toString();
    	String answer = getCountryName(correctAnswer);
    	++totalGuesses; // increment the number of guesses the user has made

    	// if the guess is correct
    	if (guess.equals(answer))
    	{
    		++correctAnswers; // increment the number of correct answers

    		// display "Correct!" in green text
    		answerTextView.setText(answer + "!");
    		answerTextView.setTextColor(getResources().getColor(R.color.correct_answer));

    		disableButtons(); // disable all answer Buttons

    		// if the user has correctly identified 10 flags
    		if (correctAnswers == 10)
    		{
    			// create a ne AlertDialog Builder
    			AlertDialog.Builder builder = new AlertDialog.Builder(this);
    			builder.setTitle(R.string.reset_quiz); // title bar string

    			// set the AlertDialog's message to display game results
    			builder.setMessage(String.format("%d, %s, %.02f%% %s",
    					totalGuesses, getResources().getString(R.string.guesses),
    					(100 / (double) totalGuesses),
    					getResources().getString(R.string.correct)));

    			builder.setCancelable(false);

    			// add "Reset Quiz" Button
    			builder.setPositiveButton(R.string.reset_quiz,
    					new DialogInterface.OnClickListener()
    			{
    				public void onClick(DialogInterface dialog, int id)
    				{
    					resetQuiz();
    				} // end method onClick
    			} // end anonymous inner class
    		); // end call to setPositiveButton

    			// create AlertDialog from the Builder
    			AlertDialog resetDialog = builder.create();
    			resetDialog.show(); // display the Dialog
    		} // end if
    		else // answer is correct but quiz is not over
    		{
    			// load the next flag after a 1-second delay
    			handler.postDelayed(new Runnable()
    			{
    				@Override
    				public void run()
    				{
    					loadNextFlag();
    				}
    			}, 1000); // 100 milliseconds for 1-second delay
    		} // end else
    	} // end if
    	else // guess was incorrect
    	{
    		//play the animation
    		flagImageView.startAnimation(shakeAnimation);

    		// display "Incorrect!" in red
    		answerTextView.setText(R.string.incorrect_answer);
    		answerTextView.setTextColor(getResources().getColor(R.color.incorrect_answer));
    		guessButton.setEnabled(false); // disable the incorrect answer
    	} // end else
    } // end method submitGuess

    // utility method that disables all answer Buttons
    private void disableButtons()
    {
    	for (int row = 0; row < buttonTableLayout.getChildCount(); ++row)
    	{
    		TableRow tableRow = (TableRow) buttonTableLayout.getChildAt(row);
    		for (int i = 0; i < tableRow.getChildCount(); ++i)
    			tableRow.getChildAt(i).setEnabled(false);
    	} // end outer for
    } // end method disableButtons

    // create constants for each menu id
    private final int CHOICES_MENU_ID = Menu.FIRST;
    private final int REGIONS_MENU_ID = Menu.FIRST + 1;

    // called when the user accesses the options menu
    @Override
    public boolean onCreateOptionsMenu(Menu menu)
    {
    	super.onCreateOptionsMenu(menu);

    	// add two options to the menu - "Choices" and "Regions"
    	menu.add(Menu.NONE, CHOICES_MENU_ID, Menu.NONE, R.string.choices);
    	menu.add(Menu.NONE, REGIONS_MENU_ID, Menu.NONE, R.string.regions);

    	return true; // display the menu
    } // end method onCreateOptionsMenu

    // called when the user selects an option from the menu
    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
    	// switch the menu id of the user-selected option
    	switch (item.getItemId())
    	{
    	case CHOICES_MENU_ID:
    		// create a list of the possible numbers of answers of choices
    		final String[] possibleChoices = getResources().getStringArray(R.array.guessesList);

    		// create a new AlertDialog Builder and set its title
    		AlertDialog.Builder choicesBuilder = new AlertDialog.Builder(this);
    		choicesBuilder.setTitle(R.string.choices);

    		//add possibleChoices items to the Dialog and set the
    		// behavior when one of the items is clicked
    		choicesBuilder.setItems(R.array.guessesList,
    				new DialogInterface.OnClickListener()
    		{
    			public void onClick(DialogInterface dialog, int item)
    			{
    				//update guessRows to match the user's choice
    				guessRows = Integer.parseInt(possibleChoices[item].toString()) / 3;
    				resetQuiz(); // reset the quiz
    			} // end method onClick
    		} // end anonymous inner class
    	); // end call to setItems

    		// create an AlertDialog from the Builder
    		AlertDialog choicesDialog = choicesBuilder.create();
    		choicesDialog.show();
    		return true;

    	case REGIONS_MENU_ID:
    		// get array of world regions
    		final String[] regionNames = regionsMap.keySet().toArray(new String[regionsMap.size()]);

    		// boolean array representing whether each region is enabled
    		boolean[] regionsEnabled = new boolean[regionsMap.size()];
    		for (int i = 0; i < regionsEnabled.length; ++i)
    			regionsEnabled[i] = regionsMap.get(regionNames[i]);

    		// create an AlertDialog Builder and set the dialog's title
    		AlertDialog.Builder regionsBuilder = new AlertDialog.Builder(this);
    		regionsBuilder.setTitle(R.string.regions);

    		// replace _ with  space in region names for display purposes
    		String[] displayNames = new String[regionNames.length];
    		for (int i = 0; i < regionNames.length; ++i)
    			displayNames[i] = regionNames[i].replace('_', ' ');

    		// add displayNames to the Dialog and set the behavior
    		// when one of the items is clicked
    		regionsBuilder.setMultiChoiceItems(
    				displayNames, regionsEnabled,
    				new DialogInterface.OnMultiChoiceClickListener()
    				{
    					@Override
    					public void onClick(DialogInterface dialog, int which,
    							boolean isChecked)
    					{
    						//include or exclude the clicked region
    						// depending on whether or not it's checked
    						regionsMap.put(regionNames[which].toString(), isChecked);
    					} // end method onClick
    				} // end anonymous inner class
    			); // end call to setMultiChoiceItems

    		//resets quiz when user presses the "Reset Quiz" Button
    		regionsBuilder.setPositiveButton(R.string.reset_quiz,
    				new DialogInterface.OnClickListener()
    		{
    			@Override
    			public void onClick(DialogInterface dialog, int button)
    			{
    				resetQuiz(); // reset the quiz
    			} // end method onClick
    		} // end anonymous inner class
    	); // end call to method setPositiveButton

    		// create a dialog from the Builder
    		AlertDialog regionsDialog = regionsBuilder.create();
    		regionsDialog.show(); // display the Dialog
    		return true;
    } // end switch

    	return super.onOptionsItemSelected(item);
    } // end method onOptionsItemSelected

    // called when a guess Button is touched
    private OnClickListener guessButtonListener = new OnClickListener()
    {
    	@Override
    	public void onClick(View v)
    	{
    		submitGuess((Button) v); // pass selected Button to submitGuess
    	} // end method onClick
    }; // end answerButtonListener
} // end FlagQuizGame