//设置翻开状态
public void setnumberofsurroundingmines(int number) {
 this.setbackgroundresource(r.drawable.selected);//设置翻开背景图
 updatenumber(number);//设置周围雷数
}

//添加雷块标识
public void setmineicon() {
 this.setbackgroundresource(r.drawable.dl);
}

//添加标记标识
public void setflagicon(boolean enabled) {

 if (!enabled) {
  this.setbackgroundresource(r.drawable.hq);
 } else {
  this.settextcolor(color.black);
 }
}

//清除所有标记
public void clearallicons() {
 this.settext("");
 this.settextcolor(r.drawable.unselected);
}

private void setboldfont() {
 this.settypeface(null, typeface.bold);
}

//翻开方块
public void openblock() {
 if (!iscovered) {
  return;
 }
 iscovered = false;
 //如果为雷设置地雷标识
 if (hasmine()) {
  setmineicon();
 } else {
  setnumberofsurroundingmines(numberofminesinsurrounding);//根据周围雷数设置翻开状态及显示数字
 }
}

package com.example.saolei;

import androidx.appcompat.app.appcompatactivity;

import android.content.intent;
import android.os.bundle;
import android.view.view;

public class levelactivity extends appcompatactivity {

 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_level);
 }

 /*根据不同难度返回相应参数*/
 public void easy(view view) {
  intent data = new intent();
  data.putextra("result", "easy");
  setresult(2, data);
  finish();
 }

 public void hard(view view) {
  intent data = new intent();
  data.putextra("result", "hard");
  setresult(2, data);
  finish();
 }

 public void return(view view) {
  intent data = new intent();
  data.putextra("result", "");
  setresult(2, data);
  finish();
 }
}

package com.example.saolei;

import androidx.appcompat.app.alertdialog;
import androidx.appcompat.app.appcompatactivity;

import android.content.intent;
import android.os.bundle;
import android.view.view;

import java.io.bufferedreader;
import java.io.file;
import java.io.fileinputstream;
import java.io.filenotfoundexception;
import java.io.ioexception;
import java.io.inputstreamreader;
import java.util.scanner;

public class menuactivity extends appcompatactivity {
 string t = "easy";
 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_menu);
 }

 @override
 //接收难度界面传回的参数并将其传回主界面处理
 protected void onactivityresult(int requestcode, int resultcode, intent data) {
  super.onactivityresult(requestcode, resultcode, data);
  if (resultcode == 2) {
   intent level = new intent();
   t = data.getstringextra("result");
   level.putextra("result", t);
   setresult(1, data);
   finish();
  }
 }

 //点击新游戏按钮，将结果传回主界面
 public void newgame(view view) {
  intent data = new intent();
  data.putextra("result", "newgame");
  setresult(1, data);
  finish();
 }

 //点击改变难度按钮，启动难度选择界面
 public void changelevel(view view) {
  intent level = new intent(menuactivity.this, levelactivity.class);
  startactivityforresult(level, 2);
 }

 //点击游戏记录按钮，显示记录
 public void record(view view) {
  string filename = getexternalcachedir().getabsolutepath() + "/gamerecord.txt";//文件路径
  file file = new file(filename);
  scanner inputstream = null;
  fileinputstream fis = null;
  bufferedreader br = null;
  string str;
  string message = "  " + "级别" + "  " + "胜负" + "   " + "时间\n";
  //若文件不存在，显示暂无记录
  if (!file.exists()) {
   new alertdialog.builder(this)
     .setmessage("暂无记录！")
     .setnegativebutton("确定", null)
     .create().show();
  }
  else {
   try {
    //读取文件记录并生成对话框显示
    inputstream = new scanner(new fileinputstream(filename));
    int i = 1;
    fis = new fileinputstream(filename);
    br = new bufferedreader(new inputstreamreader(fis));
    while ((str = br.readline()) != null) {
     message = message + (i + ". " + str + "\n");
     i++;
    }
    new alertdialog.builder(this)
      .setmessage(message)
      .setnegativebutton("确定", null)
      .create().show();
    fis.close();
    br.close();
   } catch (filenotfoundexception e) {
    e.printstacktrace();
   } catch (ioexception e) {
    e.printstacktrace();
   } finally {
    inputstream.close();
   }
  }
 }

 //点击返回按钮，回传结果到主界面
 public void return1(view view) {
  intent data = new intent();
  data.putextra("result", "start");
  setresult(1, data);
  finish();
 }
}