android端app（口算测试）

最近综合了一下android学的知识也根据up主的视频开发了一款适合儿童的口算app，下面我来大致介绍一下这款app的功能和开发思路：

首先看一下我的na'vgation(页面导航)：开始是欢迎页面，之后点击enter会进入答题页面，之后答对会得一分，每次直到答题错误会再之后的页面生成你的成绩，如果你的成绩大于历史得分对高分，就会跳转到Win页面，否则跳转到Lose页面。

 首页面：

 答题页面：

 Lose界面：

 win界面：

 下面我给一些源码供大家看一下：

java代码：

loseFragment：

package com.example.canceltext;


import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProviders;
import androidx.navigation.Navigation;

import com.example.canceltext.databinding.FragmentDefeatBinding;


/**
 * A simple {@link Fragment} subclass.
 */
public class loseFragment extends Fragment {

    public loseFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        MyViewModel myViewModel;
        myViewModel = ViewModelProviders.of(requireActivity(), new SavedStateViewModelFactory(requireActivity().getApplication(), requireActivity())).get(MyViewModel.class);

        final FragmentDefeatBinding binding ;
        binding = DataBindingUtil.inflate(inflater, R.layout.fragment_defeat,container,false);
        binding.setData(myViewModel);
        binding.setLifecycleOwner(getActivity());
        binding.button14.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Navigation.findNavController(v).navigate(R.id.action_loseFragment_to_tatelFragment);
            }
        });
        // Inflate the layout for this fragment
        return binding.getRoot();
    }
}

MainActivity：

package com.example.canceltext;

import android.content.DialogInterface;
import android.os.Bundle;


import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.NavigationUI;

public class MainActivity extends AppCompatActivity {
    NavController controller;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        controller = Navigation.findNavController(this,R.id.fragment);
        NavigationUI.setupActionBarWithNavController(this,controller);
    }

    @Override
    public boolean onSupportNavigateUp() {
        if(controller.getCurrentDestination().getId() == R.id.questionFragment){
            AlertDialog.Builder builder =new AlertDialog.Builder(this);
            builder.setTitle(R.string.quit_dialog_title);
            builder.setPositiveButton(R.string.yes, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    controller.navigateUp();
                }
            });
            builder.setNegativeButton(R.string.no, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                }
            });
        }
        return super.onSupportNavigateUp();
    }

    @Override
    public void onBackPressed() {
        onSupportNavigateUp();
    }
}

MyViewModel:

package com.example.canceltext;

import android.app.Application;

import android.content.Context;
import android.content.SharedPreferences;


import androidx.annotation.NonNull;
import androidx.lifecycle.AndroidViewModel;
import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.SavedStateHandle;


import java.util.Random;

public class MyViewModel extends AndroidViewModel {
    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";
    private static String KEY_LOSE_SCORE = "key_lose_score";
    public static 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_ANSWER,0);
            handle.set(KEY_OPERATOR,"+");
            handle.set(KEY_CURRENT_SCORE,0);
        }
        this.handle= handle;
    }

    public MutableLiveData<Integer> getLiftnumber(){
        return handle.getLiveData(KEY_LEFT_NUMBER);
    }
    public MutableLiveData<Integer> getRightnumber(){
        return handle.getLiveData(KEY_RIGHT_NUMBER);
    }
    public MutableLiveData<Integer> getHighScore(){
        return handle.getLiveData(KEY_HIGH_SCORE);
    }
    public MutableLiveData<Integer> getCurrentScore(){
        return handle.getLiveData(KEY_CURRENT_SCORE);
    }
    public MutableLiveData<Integer> getLoseScore(){
        return handle.getLiveData(KEY_LOSE_SCORE);
    }
    public MutableLiveData<String> getOperator(){
        return handle.getLiveData(KEY_OPERATOR);
    }
    public MutableLiveData<Integer> getAnswer(){
        return handle.getLiveData(KEY_ANSWER);
    }
     void generator(){
        int LEVEL = 20;
         Random random = new Random();
         int x =random.nextInt(LEVEL)+1;
         int y =random.nextInt(LEVEL)+1;
         if(x%2==0){
             getOperator().setValue("+");
             if(x>y){
                 getAnswer().setValue(x);
                 getLiftnumber().setValue(y);
                 getRightnumber().setValue(x-y);
             }else{
                 getAnswer().setValue(y);
                 getLiftnumber().setValue(x);
                 getRightnumber().setValue(y-x);
             }
         }else{
             getOperator().setValue("-");
             if(x>y){
                 getAnswer().setValue(x-y);
                 getLiftnumber().setValue(x);
                 getRightnumber().setValue(y);
             }else{
                 getAnswer().setValue(y-x);
                 getLiftnumber().setValue(y);
                 getRightnumber().setValue(x);
             }
         }

     }
     void save(){
        SharedPreferences sharedPreferences = getApplication().getSharedPreferences(SAVE_SHP_DATA_NAME,Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putInt(KEY_HIGH_SCORE,getHighScore().getValue());
        editor.apply();
     }
     @SuppressWarnings("ConstantConditions")
     void answerCurrent(){
       getCurrentScore().setValue(getCurrentScore().getValue() + 1);
       if(getCurrentScore().getValue()>getHighScore().getValue()){
           getHighScore().setValue(getCurrentScore().getValue());
            WIN_FLAG =true;
       }
       generator();
     }
}

questionFragment:

package com.example.canceltext;


import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProviders;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;

import com.example.canceltext.databinding.FragmentQuestionBinding;


/**
 * A simple {@link Fragment} subclass.
 */
public class questionFragment extends Fragment {

    public questionFragment() {
        // Required empty public constructor
    }


    @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);

        myViewModel.generator();
        final FragmentQuestionBinding binding;
        binding = DataBindingUtil.inflate(inflater, R.layout.fragment_question,container,false);
        binding.setLifecycleOwner(requireActivity());
        binding.setData(myViewModel);
        final StringBuilder builder = new StringBuilder();
        View.OnClickListener listener = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (v.getId()){
                    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.button10:
                        builder.setLength(0);
                        break;  case R.id.button11:
                        builder.append("0");
                        break;
                }
                if(builder.length()==0){
                binding.textView9.setText(getString(R.string.input));
                } else{
                 binding.textView9.setText(getString(R.string.input)+builder.toString());
                }
            }
        };
        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.button10.setOnClickListener(listener);
        binding.button11.setOnClickListener(listener);
        binding.button12.setOnClickListener(new View.OnClickListener() {
            @SuppressWarnings("ConstantConditions")
            @Override
            public void onClick(View v) {
                if(Integer.valueOf(builder.toString()).intValue()==myViewModel.getAnswer().getValue()){
                myViewModel.answerCurrent();
                builder.setLength(0);
                binding.textView9.setText(R.string.answer_correct_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);
                    }
                     myViewModel.getLoseScore().setValue(myViewModel.getCurrentScore().getValue());
                    myViewModel.getCurrentScore().setValue(0);
                }
            }
        });
          return binding.getRoot();
        // Inflate the layout for this fragment
       // return inflater.inflate(R.layout.fragment_question, container, false);
    }
}

tatelFragment:

package com.example.canceltext;


import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProviders;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;

import com.example.canceltext.databinding.FragmentQuestionBinding;


/**
 * A simple {@link Fragment} subclass.
 */
public class questionFragment extends Fragment {

    public questionFragment() {
        // Required empty public constructor
    }


    @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);

        myViewModel.generator();
        final FragmentQuestionBinding binding;
        binding = DataBindingUtil.inflate(inflater, R.layout.fragment_question,container,false);
        binding.setLifecycleOwner(requireActivity());
        binding.setData(myViewModel);
        final StringBuilder builder = new StringBuilder();
        View.OnClickListener listener = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (v.getId()){
                    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.button10:
                        builder.setLength(0);
                        break;  case R.id.button11:
                        builder.append("0");
                        break;
                }
                if(builder.length()==0){
                binding.textView9.setText(getString(R.string.input));
                } else{
                 binding.textView9.setText(getString(R.string.input)+builder.toString());
                }
            }
        };
        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.button10.setOnClickListener(listener);
        binding.button11.setOnClickListener(listener);
        binding.button12.setOnClickListener(new View.OnClickListener() {
            @SuppressWarnings("ConstantConditions")
            @Override
            public void onClick(View v) {
                if(Integer.valueOf(builder.toString()).intValue()==myViewModel.getAnswer().getValue()){
                myViewModel.answerCurrent();
                builder.setLength(0);
                binding.textView9.setText(R.string.answer_correct_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);
                    }
                     myViewModel.getLoseScore().setValue(myViewModel.getCurrentScore().getValue());
                    myViewModel.getCurrentScore().setValue(0);
                }
            }
        });
          return binding.getRoot();
        // Inflate the layout for this fragment
       // return inflater.inflate(R.layout.fragment_question, container, false);
    }
}

winFragment:

package com.example.canceltext;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProviders;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;

import com.example.canceltext.databinding.FragmentWinBinding;


/**
 * A simple {@link Fragment} subclass.
 */
public class winFragment extends Fragment {

    public winFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, final ViewGroup container,
                             Bundle savedInstanceState) {
        MyViewModel 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.setLifecycleOwner(requireActivity());
        binding.setData(myViewModel);
        binding.button13.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                NavController controller = Navigation.findNavController(v);
                controller.navigate(R.id.action_winFragment_to_tatelFragment);
            }
        });
        //nflate the layout for this fragment
        //        return binding.getRoot();
        //    }
        //} I