exam02-02

权限声明

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.exam02_2">

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".HistoryActivity"
            android:label="计算结果">
        </activity>
        <activity android:name=".MainActivity"
            android:label="质数计算">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

布局文件
activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="10dp"
    android:orientation="vertical">

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

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="开始 : " />

        <EditText
            android:id="@+id/editText_start"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Please input start"
            android:inputType="number" />

    </LinearLayout>

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

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="结束 : " />

        <EditText
            android:id="@+id/editText_end"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Please input end"
            android:inputType="number" />

    </LinearLayout>

    <TextView
        android:id="@+id/num_result"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="10dp"
        android:layout_marginTop="10dp"
        android:text="已经计算出了0个质数" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

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

            <Button
                android:id="@+id/start"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginRight="10dp"
                android:onClick="start"
                android:text="开始计算" />

            <Button
                android:id="@+id/end"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:onClick="end"
                android:text="结束计算" />

        </LinearLayout>

    </LinearLayout>

</LinearLayout>

activity_history.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context=".HistoryActivity">

    <ListView
        android:id="@+id/listview"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginStart="8dp"
        android:layout_marginLeft="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

notification_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="60dp"
    android:orientation="horizontal">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@mipmap/ic_launcher_round" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="计算完成"
                android:textSize="20sp" />

            <TextView
                android:id="@+id/time"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="11:23" />

        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <TextView
                android:id="@+id/count"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="end"
                android:text="共有10个质数" />

        </LinearLayout>

    </LinearLayout>

</LinearLayout>

MainActivity.xml

package com.example.exam02_2;

import android.Manifest;
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.content.Context;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Environment;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.NotificationCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.RemoteViews;
import android.widget.TextView;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

public class MainActivity extends AppCompatActivity {

    private EditText editText_start;
    private EditText editText_end;
    private TextView textView_result;
    private boolean flag;
    ArrayList<Integer> history = new ArrayList<Integer>();

    private final static String myChannel = "lys";
    public final static String filename = "historyList";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();

        if(ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
            ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},0);

        }




    }

    public void init(){
        editText_end = findViewById(R.id.editText_end);
        editText_start = findViewById(R.id.editText_start);
        textView_result = findViewById(R.id.num_result);
        flag = true;
    }

    public void start(View v){
        int begin = Integer.parseInt(editText_start.getText().toString());
        int end = Integer.parseInt(editText_end.getText().toString());
        flag = true;
        new MyAsyncTask().execute(begin,end);
    }

    public void end(View v){
        flag =false;
    }

    public void save(){
        try{
            File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
            File file = new File(path,filename);
            FileOutputStream out = new FileOutputStream(file,true);
            OutputStreamWriter writer = new OutputStreamWriter(out);

            for(int i=0;i<history.size();i++){
                writer.write("第"+(i+1)+"个质数是："+history.get(i)+"
");
            }
            writer.close();
            out.close();
            //BufferedOutputStream writer=new BufferedOutputStream(new OutputStream(out));
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == 0){
            if(grantResults[0]==PackageManager.PERMISSION_GRANTED){

            }else{
                ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},0);
            }
        }
    }

    //显示History菜单
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.main_menu,menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()){
            case R.id.action_history:
               // saveHistory();
                save();
                Intent intent = new Intent(MainActivity.this, HistoryActivity.class);
                //intent.putStringArrayListExtra("history",res_list);
                startActivity(intent);
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    public void sendNotification(Integer integer){
        //NotificationManager管理通知
        NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
            //Builder构造器创建Notification对象
            //NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
            NotificationChannel channel = new NotificationChannel(myChannel,"my result notification",NotificationManager.IMPORTANCE_DEFAULT);

            manager.createNotificationChannel(channel);
            NotificationCompat.Builder builder = new NotificationCompat.Builder(this,myChannel);

            RemoteViews remoteViews = new RemoteViews(getPackageName(),R.layout.notification_layout);
            remoteViews.setTextViewText(R.id.time,new SimpleDateFormat("HH:mm").format(System.currentTimeMillis()));
            remoteViews.setTextViewText(R.id.count,"共有"+integer+"个质数");

            builder.setContent(remoteViews);
            //延迟意图
//            Intent intent = new Intent(this,MainActivity.class);
//            PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
            //builder.setContentIntent(pendingIntent);

            manager.notify(100,builder.build());

        }

    }

    public void initNotification(){
        Bitmap btm = BitmapFactory.decodeResource(getResources(),
                R.mipmap.ic_launcher);
        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(
                MainActivity.this)
                .setContentTitle("计算完成")
                .setContentText("共有"+history.size()+"个质数");
        mBuilder.setTicker("New message");//第一次提示消息的时候显示在通知栏上
        mBuilder.setNumber(12);
        mBuilder.setLargeIcon(btm);
        mBuilder.setAutoCancel(true);//自己维护通知的消失

        //构建一个Intent
        Intent resultIntent = new Intent(MainActivity.this,
                MainActivity.class);
        //封装一个Intent
        PendingIntent resultPendingIntent = PendingIntent.getActivity(
                MainActivity.this, 0, resultIntent,
                PendingIntent.FLAG_UPDATE_CURRENT);
        // 设置通知主题的意图
        mBuilder.setContentIntent(resultPendingIntent);
        //获取通知管理器对象
        NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        mNotificationManager.notify(0, mBuilder.build());

    }


    class MyAsyncTask extends AsyncTask<Integer,Integer,Integer>{
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            textView_result.setText("已经算出了0个质数");
        }

        @Override
        protected void onPostExecute(Integer integer) {
            super.onPostExecute(integer);
            //sendNotification(integer);
            //initNotification();
        }

        @Override
        protected void onProgressUpdate(Integer... values) {
            super.onProgressUpdate(values);
            textView_result.setText("已经算出了"+values[0]+"个质数");
        }

        @Override
        protected Integer doInBackground(Integer... integers) {
            for (int i=integers[0]; flag&&i<=integers[1]; i++) {
                boolean isPrime=true;
                for (int j=2; j<=Math.sqrt(i); j++) {

                    if(i%j==0) {
                        isPrime=false;
                        break;
                    }
                    try {
                        Thread.sleep(50);
                    }   catch (InterruptedException e) {
                        e.printStackTrace();
                    }

                }
                if (isPrime){
                    //i是素数
                    history.add(i);
                }
                publishProgress(history.size());
            }
            initNotification();
            return history.size();
        }
    }
}

HistoryActivity.xml

package com.example.exam02_2;

import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.List;

public class HistoryActivity extends AppCompatActivity {

    private ListView listView;
    private List<String> historyList = new ArrayList<>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_history);
        readFile();
        listView = findViewById(R.id.listview);
        ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,historyList);
        listView.setAdapter(adapter);
    }


    public void readFile(){
        File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
        File file = new File(path,MainActivity.filename);
        try {
            FileInputStream fis = new FileInputStream(file);
            InputStreamReader reader = new InputStreamReader(fis);
            BufferedReader  br = new BufferedReader(reader);
            String line = "";
            while((line=br.readLine())!=null) {
                historyList.add(line.trim());
            }
            br.close();
            reader.close();
            fis.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }catch (Exception e){
            e.printStackTrace();
        }

    }
}