Android编程入门-第5天

今天主要学习了更新控制器层的有关内容，了解到封装公共代码的技巧以及增加按钮变量的方法。
对QuizActivity.java进行修改后，完整代码如下：package com.example.geoquiz;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class QuizActivity extends Activity {

private Button mTrueButton;
private Button mFalseButton;
private Button mNextButton;
private TextView mQuestionTextView;

private Question[] mQuestionBank = new Question[]{
new Question(R.string.question_australia, true),
new Question(R.string.question_oceans, true),
new Question(R.string.question_mideast, false),
new Question(R.string.question_africa, false),
new Question(R.string.question_america, true),
new Question(R.string.question_asia, true)
};

private int mCurrentIndex = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_quiz);

mQuestionTextView = (TextView) findViewById(R.id.question_text_view);

mTrueButton = (Button) findViewById(R.id.true_button);
mFalseButton = (Button) findViewById(R.id.false_button);

mTrueButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
checkAnswer(true);
}
});
mFalseButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
checkAnswer(false);
}
});

mNextButton = (Button) findViewById(R.id.next_button);
mNextButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
mCurrentIndex = (mCurrentIndex + 1) % mQuestionBank.length;
updateQuestion();
}
});
updateQuestion();
}

private void updateQuestion(){
int question = mQuestionBank[mCurrentIndex].getTextResId();
mQuestionTextView.setText(question);
}

private void checkAnswer(boolean userPressedTrue){
boolean answerIsTrue = mQuestionBank[mCurrentIndex].isAnswerTrue();

int messageResId = 0;

if(userPressedTrue == answerIsTrue){
messageResId = R.string.correct_toast;
}else{
messageResId = R.string.incorrect_toast;
}
Toast.makeText(this, messageResId, Toast.LENGTH_SHORT).show();
}
}