Android实现短信加密功能（发送加密短信、解密本地短信）

短信加密此类功能由于新手学习的需求量较小，所以在网上很少有一些简单的demo供新手参考。小编做到此处也是花了比较多的时间自我构思，具体的过程也是不过多描述了，讲一下demo的内容。

demo功能：

1、可以发送短信并且加密（通过改变string中的char）

2、能够查看手机中的短信

3、能够给收到的加密短信解密。

涉及到的知识点：

1、intent bundle传递

2、ContentResolver获取手机短信

3、listveiw与simpleAdapter

4、发送短信以及为发送短信设置要监听的广播

遇到的问题：

1、发送短信字符过长会导致发送失败

解决方法：设置发送每条短信为70个字以内。

原理：每条短信限制160字符以内，每个汉字是2个字符。平时我们发送短信几乎不限长度，是因为一旦超过了单条短信的长度，手机会自动分多条发送，然后接收方分多条接收后整合在一起显示。

代码：

MainActivity:

import android.app.Activity;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button; 

public class MainActivity extends Activity { 

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main); 

 InitView();
 } 

 private void InitView() {
 Button send=(Button)findViewById(R.id.bt_send);
 Button receive=(Button)findViewById(R.id.bt_receive); 

 send.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
  Intent intent=new Intent(MainActivity.this,SendActivity.class);
  startActivity(intent);
  }
 }); 

 receive.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
  Intent intent=new Intent(MainActivity.this,ReceiveActivity.class);
  startActivity(intent);
  }
 });
 }
}

SendActivity:

import android.app.Activity;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast; 

/**
 * Created by 佳佳 on 2015/12/21.
 */
public class SendActivity extends Activity { 

 private IntentFilter sendFilter;
 private SendStatusReceiver sendStatusReceiver; 

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_send); 

 InitView();
 } 

 private void InitView() {
 Button cancel = (Button) findViewById(R.id.cancel_edit);
 Button send = (Button) findViewById(R.id.send_edit);
 final EditText phone = (EditText) findViewById(R.id.phone_edit_text);
 final EditText msgInput = (EditText) findViewById(R.id.content_edit_text); 

 //为发送短信设置要监听的广播
 sendFilter = new IntentFilter();
 sendFilter.addAction("SENT_SMS_ACTION");
 sendStatusReceiver = new SendStatusReceiver();
 registerReceiver(sendStatusReceiver, sendFilter); 

 send.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View v) {
  Toast.makeText(SendActivity.this, "加密发送中，请稍后...", Toast.LENGTH_SHORT).show();
  //接收edittext中的内容,并且进行加密
  //倘若char+8超出了表示范围，则把原字符发过去
  String address = phone.getText().toString();
  String content = msgInput.getText().toString();
  String contents = "";
  for (int i = 0; i < content.length(); i++) {
   try {
   contents += (char) (content.charAt(i) + 8);
   }catch (Exception e) {
   contents += (char) (content.charAt(i));
   }
  } 

  //Log.i("hahaha",contents); 

  //发送短信
  //并使用sendTextMessage的第四个参数对短信的发送状态进行监控
  SmsManager smsManager = SmsManager.getDefault();
  Intent sentIntent = new Intent("SENT_SMS_ACTION");
  PendingIntent pi = PendingIntent.getBroadcast(
   SendActivity.this, 0, sentIntent, 0);
  smsManager.sendTextMessage(address, null,
   contents.toString(), pi, null);
  }
 }); 

 cancel.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
  finish();
  }
 });
 } 

 class SendStatusReceiver extends BroadcastReceiver { 

 @Override
 public void onReceive(Context context, Intent intent) {
  if (getResultCode() == RESULT_OK) {
  //发送成功
  Toast.makeText(context, "Send succeeded", Toast.LENGTH_LONG)
   .show(); 

  Intent intent1 = new Intent(SendActivity.this, ReceiveActivity.class);
  startActivity(intent1);
  finish();
  } else {
  //发送失败
  Toast.makeText(context, "Send failed", Toast.LENGTH_LONG)
   .show();
  }
 } 

 } 

 @Override
 protected void onDestroy() {
 super.onDestroy();
 //在Activity摧毁的时候停止监听
 unregisterReceiver(sendStatusReceiver);
 }
}

ReceiveActivity:

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView; 

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map; 

public class ReceiveActivity extends Activity implements AdapterView.OnItemClickListener{
 private TextView Tv_address;
 private TextView Tv_body;
 private TextView Tv_time;
 private ListView listview;
 private List<Map<String, Object>> dataList;
 private SimpleAdapter simple_adapter; 

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_receive); 

 InitView();
 } 

 @Override
 protected void onStart() {
 super.onStart();
 RefreshList();
 } 

 private void InitView() {
 Tv_address = (TextView) findViewById(R.id.tv_address);
 Tv_body = (TextView) findViewById(R.id.tv_body);
 Tv_time = (TextView) findViewById(R.id.tv_time);
 listview = (ListView) findViewById(R.id.list_receive);
 dataList = new ArrayList<Map<String, Object>>(); 

 listview.setOnItemClickListener(this);
 } 

 private void RefreshList() {
 //从短信数据库读取信息
 Uri uri = Uri.parse("content://sms/");
 String[] projection = new String[]{"address", "body", "date"};
 Cursor cursor = getContentResolver().query(uri, projection, null, null, "date desc");
 startManagingCursor(cursor); 

 //此处为了简化代码提高效率，仅仅显示20条最近短信
 for (int i = 0; i < 20; i++) {
  //从手机短信数据库获取信息
  if(cursor.moveToNext()) {
  String address = cursor.getString(cursor.getColumnIndex("address"));
  String body = cursor.getString(cursor.getColumnIndex("body"));
  long longDate = cursor.getLong(cursor.getColumnIndex("date"));
  //将获取到的时间转换为我们想要的方式
  SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
  Date d = new Date(longDate);
  String time = dateFormat.format(d); 

  Map<String, Object> map = new HashMap<String, Object>();
  map.put("address", address);
  map.put("body", body+"body");
  map.put("time", time+" time");
  dataList.add(map);
  }
 } 

 simple_adapter = new SimpleAdapter(this, dataList, R.layout.activity_receive_list_item,
  new String[]{"address", "body", "time"}, new int[]{
  R.id.tv_address, R.id.tv_body, R.id.tv_time});
 listview.setAdapter(simple_adapter);
 } 

 @Override
 public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
 //获取listview中此个item中的内容
 //content的内容格式如下
 //{body=[B@43c2da70body, address=+8615671562394address, time=2015-12-24 11:55:50time}
 String content = listview.getItemAtPosition(i) + "";
 String body = content.substring(content.indexOf("body=") + 5,
  content.indexOf("body,"));
 //Log.i("hahaha",body);
 String address = content.substring(content.indexOf("address=") + 8,
  content.lastIndexOf(","));
 //Log.i("hahaha",address);
 String time = content.substring(content.indexOf("time=") + 5,
  content.indexOf(" time}"));
 //Log.i("hahaha",time); 

 //使用bundle存储数据发送给下一个Activity
 Intent intent=new Intent(ReceiveActivity.this,ReceiveActivity_show.class);
 Bundle bundle = new Bundle();
 bundle.putString("body", body);
 bundle.putString("address", address);
 bundle.putString("time", time);
 intent.putExtras(bundle);
 startActivity(intent); 

 }
}

ReceiveActivity_show:

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView; 

public class ReceiveActivity_show extends Activity {
 private TextView Address_show;
 private TextView Time_show;
 private TextView Early_body_show;
 private TextView Late_body_show; 

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_receive_show); 

 InitView();
 } 

 private void InitView() { 

 Address_show = (TextView) findViewById(R.id.address_show);
 Time_show = (TextView) findViewById(R.id.time_show);
 Early_body_show = (TextView) findViewById(R.id.early_body_show);
 Late_body_show = (TextView) findViewById(R.id.late_body_show); 

 //接收内容和id
 Bundle bundle = this.getIntent().getExtras();
 String body = bundle.getString("body");
 String time = bundle.getString("time");
 String address = bundle.getString("address"); 

 Address_show.setText(address);
 Early_body_show.setText(body);
 Time_show.setText(time); 

 //对短信消息进行解密后显示在textview中
 //倘若char+8超出了表示范围，则直接按照原字符解析
 String real_content = "";
 for (int i = 0; i < body.length(); i++) {
  try {
  char textchar=(char) (body.charAt(i) + 8);
  real_content += (char) (body.charAt(i) - 8);
  }catch (Exception e){
  real_content += (char) (body.charAt(i));
  }
 }
 Late_body_show.setText(real_content);
 } 

}

activity_main:

<?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:orientation="vertical"> 

 <TextView
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:background="#000"
 android:padding="12dp"
 android:text="加密短信"
 android:textColor="#fff"
 android:textSize="25sp"
 android:textStyle="bold" />
 <Button
 android:layout_marginTop="120dp"
 android:id="@+id/bt_send"
 android:layout_width="200dp"
 android:layout_height="80dp"
 android:text="发送加密短信"
 android:layout_gravity="center"
 android:textSize="20dp"/>
 <Button
 android:id="@+id/bt_receive"
 android:layout_width="200dp"
 android:layout_height="80dp"
 android:layout_gravity="center"
 android:text="解密本地短信"
 android:textSize="20dp"
 android:layout_below="@+id/bt_send"/> 

</LinearLayout>

activity_send:

<?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:orientation="vertical"> 

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
 android:padding="10dp"> 

 <TextView
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:text="加密短信发送"
  android:textColor="#000"
  android:textSize="35sp" /> 

 <View
  android:layout_width="match_parent"
  android:layout_height="3dp"
  android:layout_marginBottom="20dp"
  android:background="#CECECE" /> 

 <TextView
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="发送至："
  android:textSize="25sp" /> 

 <EditText
  android:id="@+id/phone_edit_text"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_marginBottom="10dp"
  android:background="@drawable/edit_text_style"
  android:hint="接收人手机号码"
  android:maxLength="15"
  android:maxLines="1"
  android:textSize="19sp"
  android:singleLine="true" /> 

 <TextView
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="发送内容"
  android:textSize="25sp" /> 

 <EditText
  android:id="@+id/content_edit_text"
  android:layout_width="match_parent"
  android:layout_height="0dp"
  android:layout_weight="1"
  android:background="@drawable/edit_text_style"
  android:gravity="start"
  android:hint="单条短信请保持在70字以内"
  android:maxLength="70"
  android:textSize="19sp"
  /> 

 <LinearLayout
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_margin="10dp"> 

  <Button
  android:id="@+id/cancel_edit"
  android:layout_width="0dp"
  android:layout_height="wrap_content"
  android:layout_weight="1"
  android:text="取消编辑"
  android:textSize="20sp" /> 

  <Button
  android:id="@+id/send_edit"
  android:layout_width="0dp"
  android:layout_height="wrap_content"
  android:layout_weight="1"
  android:text="发 送"
  android:textSize="20sp" />
 </LinearLayout>
 </LinearLayout>
</LinearLayout>

activity_receive:

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

 <TextView
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:padding="10dp"
 android:text="所有短信"
 android:textColor="#fff"
 android:background="#000"
 android:textSize="23sp"
 android:textStyle="bold"/> 

 <ListView
 android:id="@+id/list_receive"
 android:layout_width="match_parent"
 android:layout_height="match_parent"></ListView> 

</LinearLayout>

activity_receive_show:

<?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:orientation="vertical"> 

 <TextView
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:background="#000"
 android:padding="12dp"
 android:text="短信解密"
 android:textColor="#fff"
 android:textSize="25sp"
 android:textStyle="bold" /> 

 <TableLayout
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
 android:padding="10dp"
 android:stretchColumns="1"
 android:shrinkColumns="1"> 

 <TableRow android:layout_marginTop="10dp"
  android:layout_width="match_parent"
  > 

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="号码："
  android:textColor="#000"
  android:textSize="20sp" /> 

  <TextView
  android:id="@+id/address_show"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="10dp"
  android:background="@drawable/edit_text_style"
  android:maxLines="1"
  android:singleLine="true"
  android:textSize="18sp" />
 </TableRow
  > 

 <TableRow
  android:layout_width="match_parent"
  android:layout_marginBottom="10dp"
  > 

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="时间："
  android:textColor="#000"
  android:textSize="20sp" /> 

  <TextView
  android:id="@+id/time_show"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="10dp"
  android:background="@drawable/edit_text_style"
  android:maxLines="1"
  android:textSize="18sp" />
 </TableRow> 

 <TableRow android:layout_marginBottom="10dp"
  android:layout_width="match_parent"> 

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="原文本："
  android:textColor="#000"
  android:textSize="20sp" /> 

  <TextView
  android:id="@+id/early_body_show"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:background="@drawable/edit_text_style"
  android:minLines="6"
  android:maxLines="6"
  android:textSize="18sp"
  />
 </TableRow> 

 <TableRow
  android:layout_width="match_parent"> 

  <TextView
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_marginBottom="5dp"
  android:text="解析后："
  android:textColor="#000"
  android:textSize="20sp" /> 

  <TextView
  android:id="@+id/late_body_show"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:background="@drawable/edit_text_style"
  android:minLines="6"
  android:maxLines="6"
  android:singleLine="false"
  android:textSize="18sp"
  />
 </TableRow> 

 </TableLayout>
</LinearLayout> 

以上就是本文的全部内容，android实现短信加密，实现发送加密短信、解密本地短信，希望对大家的学习有所帮助。