android入门小Demo
16lz
2021-01-26
分享一个android端的小例子，代码虽少，五脏俱全。
得到的效果是
废话不多说，直接上代码。
我们先看项目的结构。
我们的主活动页面是activity_main.xml 代码如下
<?xml version="1.0" encoding="utf-8"?> 对应的活动页面是MainActivity.java，代码如下：
package ligz.com.geoquiz;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends AppCompatActivity { private static final String TAG = "QuizActivity"; private static final String KEY_INDEX = "index"; private Button mTrueButton; private Button mFalseButton; private Button mNextButton; private TextView mQuestionTextView; private Button mCheatButtton;//作弊的按钮 private boolean mIsCheater; private TrueFalse[] mQuestionBank = new TrueFalse[]{ new TrueFalse(R.string.question_text,true), new TrueFalse(R.string.question_text1,true), new TrueFalse(R.string.question_text2,true), new TrueFalse(R.string.question_text3,true), new TrueFalse(R.string.question_text4,false), }; private int mCurrentIndex = 0; private void updateQuestion(){ int question = mQuestionBank[mCurrentIndex].getmQuestion(); mQuestionTextView.setText(question); } private void checkAnswer(boolean userPressedTrue){ boolean answerIsTrue = mQuestionBank[mCurrentIndex].ismTrueQuestion(); int messageResId = 0; if(mIsCheater){ messageResId = R.string.judgment_toast; }else{ if(userPressedTrue == answerIsTrue){ messageResId = R.string.correct_toast; }else{ messageResId = R.string.incorrect_toast; } } Toast.makeText(this,messageResId,Toast.LENGTH_SHORT).show(); } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Log.d(TAG, "onCreate(Bundel) called"); setContentView(R.layout.activity_main); //从数组中拿出问题放入TextView mQuestionTextView = (TextView)findViewById(R.id.question_text_view); /** * 正确按钮 */ mTrueButton = (Button)findViewById(R.id.true_button); //使用监听器 mTrueButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { checkAnswer(true); } }); /** * 错误按钮 */ mFalseButton = (Button) findViewById(R.id.false_button); mFalseButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { checkAnswer(false); } }); /** * 下一道题目按钮 */ mNextButton = (Button)findViewById(R.id.next_button); mNextButton.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View view) { mCurrentIndex = (mCurrentIndex + 1) % mQuestionBank.length; mIsCheater = false; updateQuestion(); } }); if(savedInstanceState != null){ mCurrentIndex = savedInstanceState.getInt(KEY_INDEX, 0); } /** * 作弊的按钮跳转 */ mCheatButtton = (Button) findViewById(R.id.cheat_button); mCheatButtton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //Start CheatActivity //跳转activity Intent i = new Intent(MainActivity.this, CheatActivity.class); //传递内容 boolean answerIsTrue = mQuestionBank[mCurrentIndex].ismTrueQuestion(); i.putExtra(CheatActivity.EXTRA_ANSWER_IS_TRUE, answerIsTrue); //startActivity(i); startActivityForResult(i,0);//第二个参数是请求代码，当一个activity有多个子activity时，且需要区分消息反馈 } }); updateQuestion(); } @Override public void onSaveInstanceState(Bundle savedInstanceState){//记住当前的答案，当屏幕旋转时，仍可以回到当前问题 super.onSaveInstanceState(savedInstanceState); Log.i(TAG, "onSavedInstanceState"); savedInstanceState.putInt(KEY_INDEX, mCurrentIndex); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data){// if(data == null){ return; } mIsCheater = data.getBooleanExtra(CheatActivity.EXTRA_ANSWER_SHOWN, false); }}点击cheat按钮，进入查看答案的页面，对应的xml文件是activity_cheat.xml如下：
<?xml version="1.0" encoding="utf-8"?> 对应的CheatActivity.java文件如下：
package ligz.com.geoquiz;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.TextView;/** * Created by Es muss sein on 2018/9/4. */public class CheatActivity extends Activity{ public static final String EXTRA_ANSWER_IS_TRUE = "ligz.com.geoquiz.answer_is_true"; public static final String EXTRA_ANSWER_SHOWN = "ligz.com.geoquiz.answer_show"; private boolean mAnswerIsTrue; private TextView mAnswerTextView; private Button mShowAnswer; private void setAnswerShowResult(boolean isAnswerShown){ Intent data = new Intent(); data.putExtra(EXTRA_ANSWER_SHOWN, isAnswerShown); setResult(RESULT_OK, data); } @Override protected void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.activity_cheat); mAnswerIsTrue = getIntent().getBooleanExtra(EXTRA_ANSWER_IS_TRUE, false); mAnswerTextView = (TextView)findViewById(R.id.answerTextView); //答案不会显示除非用户按下按钮 setAnswerShowResult(false); mShowAnswer = (Button)findViewById(R.id.showAnswerButton); mShowAnswer.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if(mAnswerIsTrue){ mAnswerTextView.setText(R.string.true_button); }else{ mAnswerTextView.setText(R.string.false_button); } setAnswerShowResult(true); } }); }}model文件TrueFalse.java如下：
package ligz.com.geoquiz;/** * Created by Es muss sein on 2018/9/3. */public class TrueFalse { private int mQuestion; private boolean mTrueQuestion; public TrueFalse(int mQuestion, boolean mTrueQuestion){ this.mQuestion = mQuestion; this.mTrueQuestion = mTrueQuestion; } public int getmQuestion() { return mQuestion; } public void setmQuestion(int mQuestion) { this.mQuestion = mQuestion; } public boolean ismTrueQuestion() { return mTrueQuestion; } public void setmTrueQuestion(boolean mTrueQuestion) { this.mTrueQuestion = mTrueQuestion; }}对应Strings.xml如下：
GeoQuiz 中国哲学简史的作者是否是冯友兰 1984的作者是乔治奥威尔吗 王小波写过沉默的大多数吗 意志和表象的世界是叔本华的作品吗 牛棚杂忆和动物庄园的作者是同一人吗 cheat! 你确定要查看答案吗 查看答案 Cheating is wrong 对 错 Settings 回答正确 回答错误 下一题 csdn下载
更多相关文章
- android源代码下载及编译开发
- Android(安卓)ril原生代码（C／C＋＋）和java代码部分分析
- Android(安卓)读取元素的数据
- Android中阻止AlertDialog关闭实例代码
- Android的应用程序组件---四大组件
- react-native 实现购物车滑动删除效果的示例代码
- 浅谈WebView的使用
- 【Android】Android中使用JNI调用底层C++代码
- 提高 Android(安卓)代码质量的4个工具