1.5Android编程权威指南第一章代码

activity_quiz.activity

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical"
    tools:context="com.study.android.geoquizactivity.QuizActivity">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:padding="10dp"
        android:text="@string/question_text"/>

    <LinearLayout android:layout_width="wrap_content"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal">

        <Button
            android:id="@+id/true_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/true_button"/>

        <Button
            android:id="@+id/false_button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/false_button"/>
    </LinearLayout>
</LinearLayout>

strings.xml

<resources>
    <string name="app_name">GeoQuizActivity</string>
    <string name="question_text">Canberra is the captical of Australia</string>
    <string name="true_button">True</string>
    <string name="false_button">False</string>
    <string name="correct_toast">Correct</string>
    <string name="incorrect_toast">InCorrect</string>
</resources>

QuizActivity.java

public class QuizActivity extends AppCompatActivity {


    private Button mTrueButton;
    private Button mFalseButton;

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

    private void initView() {
        //实例化控件
        mTrueButton = findViewById(R.id.true_button);
        mFalseButton = findViewById(R.id.false_button);
    }

    private void initEvent() {
        //设置匿名内部类监听器
        mTrueButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(QuizActivity.this, R.string.correct_toast, Toast.LENGTH_SHORT).show();
            }
        });

        mFalseButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //定制Toast消息,出现在屏幕上方
                Toast toast = Toast.makeText(QuizActivity.this, R.string.incorrect_toast, Toast.LENGTH_SHORT);
                toast.setGravity(Gravity.TOP, 0, 0);
                toast.show();
            }
        });
    }
}

PS：
在AS中加m前缀区别

Settings中加了m，设置成全局变量后都会在最前面加上m字符
详细设置步骤：

Demo下载地址：
https://download.csdn.net/download/weixin_43953649/10849702