Android-寒假学习-阶段总结(20集)-口算测试APP

说在前面：

1、视频教程：https://www.bilibili.com/video/av60445113/?spm_id_from=333.788.videocard.0

2、老师的源码：https://github.com/longway777/Android-2019-Demo-CalculationTest

3、我的源码：https://github.com/xiaotian12-call/Learning/tree/0c345ee43df1f3bb0bc161087880b416a579a707

一、界面的搭建：

1、创建四个界面

　　

 　　

1）TitleFragment.java&fragment_title.xml

(注：1、imageview所用图片是网上随意下载的；2、右上角的"high score ：%d"，需要与viewmodel中的数据绑定；3、点击Entry，进入答题界面：

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        final MyViewModel myViewModel;
        myViewModel = ViewModelProviders.of(requireActivity(),new SavedStateViewModelFactory(requireActivity().getApplication(),requireActivity())).get(MyViewModel.class);
        FragmentTitleBinding binding;
        binding = DataBindingUtil.inflate(inflater,R.layout.fragment_title,container,false);
        binding.setData(myViewModel);
        binding.setLifecycleOwner(requireActivity());
        binding.button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                NavController controller = Navigation.findNavController(v);
                controller.navigate(R.id.action_titleFragment_to_questionFragment);
                myViewModel.getCurrentScore().setValue(0);
                myViewModel.generator();
            }
        });
        return binding.getRoot();
        // Inflate the layout for this fragment
        //return inflater.inflate(R.layout.fragment_title, container, false);
    }

)

2）QuestionFragment.java&fragment_question.xml

 （注：1、0-9和重置键设置监听：

View.OnClickListener listener = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (v.getId()) {
                    case R.id.button0:
                        builder.append("0");
                        break;
                    case R.id.button1:
                        builder.append("1");
                        break;
                    case R.id.button2:
                        builder.append("2");
                        break;
                    case R.id.button3:
                        builder.append("3");
                        break;
                    case R.id.button4:
                        builder.append("4");
                        break;
                    case R.id.button5:
                        builder.append("5");
                        break;
                    case R.id.button6:
                        builder.append("6");
                        break;
                    case R.id.button7:
                        builder.append("7");
                        break;
                    case R.id.button8:
                        builder.append("8");
                        break;
                    case R.id.button9:
                        builder.append("9");
                        break;
                    case R.id.buttonclaer:
                        builder.setLength(0);
                        break;
                }
                if (builder.length() == 0) {
                    binding.textView9.setText(getString(R.string.input_hint));
                } else {
                    binding.textView9.setText(builder.toString());
                }

            }
        };

        binding.button0.setOnClickListener(listener);
        binding.button1.setOnClickListener(listener);
        binding.button2.setOnClickListener(listener);
        binding.button3.setOnClickListener(listener);
        binding.button4.setOnClickListener(listener);
        binding.button5.setOnClickListener(listener);
        binding.button6.setOnClickListener(listener);
        binding.button7.setOnClickListener(listener);
        binding.button8.setOnClickListener(listener);
        binding.button9.setOnClickListener(listener);
        binding.buttonclaer.setOnClickListener(listener);

2、提交答案设置监听：

binding.buttonsubmit.setOnClickListener(new View.OnClickListener() {
            @SuppressWarnings("ConstantConditions")
            @Override
            public void onClick(View v) {
                if (builder.length() == 0) {
                    builder.append("-1");
                }
                if (Integer.valueOf(builder.toString()).intValue() == myViewModel.getAnswer().getValue()) {
                    myViewModel.answerCorrect();
                    builder.setLength(0);
                    binding.textView9.setText(R.string.answer_currect_message);
                    //builder.append(getString(R.string.answer_corrrect_message));
                } else {
                    NavController controller = Navigation.findNavController(v);
                    if (myViewModel.win_flag) {
                        controller.navigate(R.id.action_questionFragment_to_winFragment);
                        myViewModel.win_flag = false;
                        myViewModel.save();
                    } else {
                        controller.navigate(R.id.action_questionFragment_to_loseFragment);
                    }
                }

            }
        });
        return binding.getRoot();
        // Inflate the layout for this fragment
        //return inflater.inflate(R.layout.fragment_question, container, false);
    }

）

3）WinFragment.java&fragment_win.xml

 （注：1、矢量图的创建：

2、back键的监听及动作：

@Override
    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        MyViewModel myViewModel = ViewModelProviders.of(requireActivity(),new SavedStateViewModelFactory(requireActivity().getApplication(),requireActivity())).get(MyViewModel.class);
        FragmentWinBinding binding;
        binding = DataBindingUtil.inflate(inflater,R.layout.fragment_win,container,false);
        binding.setData(myViewModel);
        binding.setLifecycleOwner(requireActivity());
        binding.buttonWb.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Navigation.findNavController(v).navigate(R.id.action_winFragment_to_titleFragment);
            }
        });
        return binding.getRoot();
    }

）

4）LostFragment.java&fragment_lost.xml

（注：back键的监听及动作:

@Override
    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        MyViewModel myViewModel = ViewModelProviders.of(requireActivity(),new SavedStateViewModelFactory(requireActivity().getApplication(),requireActivity())).get(MyViewModel.class);
        FragmentLoseBinding binding;
        binding = DataBindingUtil.inflate(inflater,R.layout.fragment_lose,container,false);
        binding.setData(myViewModel);
        binding.setLifecycleOwner(requireActivity());
        binding.buttonLB.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Navigation.findNavController(v).navigate(R.id.action_loseFragment_to_titleFragment);
            }
        });
        return binding.getRoot();
    }

）

2、创建导航图表导入LoseFragment，确定页面跳转关系

1）创建navigation：

 2）导入fargment:

 3)确定页面跳转关系

二、数据与逻辑的处理

1、数据规划，使用viewmodel管理：最高纪录 ：highScore、算式左操作数：leftNumber、算式右操作数：rightNumber、运算符：operator、答案：answer、当前得分：currentScore。

private SavedStateHandle handle;
    private static String KEY_HIGH_SCORE = "key_high_score";
    private static String KEY_LEFT_NUMBER = "key_left_number";
    private static String KEY_RIGHT_NUMBER = "key_right_number";
    private static String KEY_OPERATOR = "key_operator";
    private static String KEY_ANSWER = "key_answer";
    private static String SAVE_SHP_DATA_NAME = "save_shp_data_name";
    private static String KEY_CURRENT_SCORE = "key_current_score";
    boolean win_flag = false;
    public MyViewModel(@NonNull Application application, SavedStateHandle handle) {
        super(application);
        if (!handle.contains(KEY_HIGH_SCORE)) {
            SharedPreferences shp = getApplication().getSharedPreferences(SAVE_SHP_DATA_NAME, Context.MODE_PRIVATE);
            handle.set(KEY_HIGH_SCORE,shp.getInt(KEY_HIGH_SCORE,0));
            handle.set(KEY_LEFT_NUMBER,0);
            handle.set(KEY_RIGHT_NUMBER,0);
            handle.set(KEY_OPERATOR,"+");
            handle.set(KEY_ANSWER,0);
            handle.set(KEY_CURRENT_SCORE,0);
        }
        this.handle = handle;
    }
    public MutableLiveData<Integer>getLeftNumber(){
        return handle.getLiveData(KEY_LEFT_NUMBER);
    }
    public MutableLiveData<Integer>getRightNumber(){
        return handle.getLiveData(KEY_RIGHT_NUMBER);
    }
    public MutableLiveData<String>getOperator() {
        return handle.getLiveData(KEY_OPERATOR);
    }
    public MutableLiveData<Integer>getHighScore(){
        return handle.getLiveData(KEY_HIGH_SCORE);
    }
    public MutableLiveData<Integer>getCurrentScore(){
        return handle.getLiveData(KEY_CURRENT_SCORE);
    }
    public MutableLiveData<Integer>getAnswer(){
        return handle.getLiveData(KEY_ANSWER);
    }

2、生成运算式

1）设置挑战难度：20（20以内的运算）；

2）生成两个随机数，当是加法运算时、以大的作为answer，小的作为leftNumber，大减小作为rightNumber；当为减法运算时，大的为被减数，小的为减数，大的减小的是答案。

void generator(){
        int LEVEL = 20;
        Random random = new Random();
        int x,y;
        x = random.nextInt(LEVEL) + 1;
        y = random.nextInt(LEVEL) + 1;
        if (x%2==0) {
            getOperator().setValue("+");
            if (x>y) {
                getAnswer().setValue(x);
                getLeftNumber().setValue(y);
                getRightNumber().setValue(x - y);
            } else {
                getAnswer().setValue(y);
                getLeftNumber().setValue(x);
                getRightNumber().setValue(y - x);
            }

        } else {
            getOperator().setValue("-");
            if (x>y) {
                getAnswer().setValue(x - y);
                getLeftNumber().setValue(x);
                getRightNumber().setValue(y);
            } else {
                getAnswer().setValue(y - x);
                getLeftNumber().setValue(y);
                getRightNumber().setValue(x);
            }
        }
    }

3）破纪录，保存highScore

void save() {
        SharedPreferences shp = getApplication().getSharedPreferences(SAVE_SHP_DATA_NAME,Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = shp.edit();
        editor.putInt(KEY_HIGH_SCORE,getHighScore().getValue());
        editor.apply();
    }

4）正确时，判断是否需要更新highScore，并生成新的算式

void answerCorrect(){
        getCurrentScore().setValue(getCurrentScore().getValue() + 1 );
        if (getCurrentScore().getValue() > getHighScore().getValue()) {
            getHighScore().setValue(getCurrentScore().getValue());
            win_flag = true;
        }
        generator();
    }