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public class MainActivity extends AppCompatActivity {    private static final int JSON_ERROR = 3;    private static final int ENTER_HOME = 0;    private static final int ENTER_DIALOG = 1;    private static final int URL_ERROR = 2;    private static final int NET_ERROR = 4;    private TextView tv;    private String version;    private String downloadUrl;    private String desc;private SharedPreferences sp;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);//        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);//        setSupportActionBar(toolbar);        sp=getSharedPreferences("connfig",MODE_PRIVATE);        tv = findViewById(R.id.tv_version);        tv.setText("版本：1.1.1");        Boolean update=sp.getBoolean("update",false);//获取保存的是否自动更新的设置        if(update){            checkUpdate();        }else {//不检查更新，延迟两秒后进入主页面            handler.postDelayed(new Runnable() {                @Override                public void run() {                    enterhome();                }            }, 2000);        }//给activitymain设置动画        AlphaAnimation aa = new AlphaAnimation(0.3f, 1.0f);        aa.setStartTime(1000);        findViewById(R.id.main).startAnimation(aa);    }    //子线程请求网络数据后通过handlemessage发送数据，在主线程用handler更新UI    private Handler handler = new Handler() {        @SuppressLint("WrongConstant")        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {                case ENTER_HOME://进入主页面                    enterhome();                    break;                case ENTER_DIALOG://显示对话框                    showUpdateDialog();                    enterhome();                    break;                case JSON_ERROR://json 解析出错                    Toast.makeText(getApplicationContext(), "json解析错误", 0).show();                    enterhome();                    break;                case URL_ERROR://url 出错                    enterhome();                    break;                case NET_ERROR://网络出错                    enterhome();                    break;            }        }    };    //显示dialog    private void showUpdateDialog() {        AlertDialog.Builder build = new AlertDialog.Builder(this);//        build.setCancelable(false);//设置点返回按钮和dialog外不起作用，一般做强制升级的时候才用；        //点击手机返回键或dialog外的activty时调用的监听方法        build.setOnCancelListener(new DialogInterface.OnCancelListener() {            @Override            public void onCancel(DialogInterface dialog) {               enterhome();//进入主页面                dialog.dismiss();            }        });        build.setTitle("提示");        build.setMessage(desc);        build.setPositiveButton("立即升级", new DialogInterface.OnClickListener() {            @SuppressLint("WrongConstant")            @Override            public void onClick(DialogInterface dialog, int which) {//下载apk,并且替换                if (Environment.getExternalStorageDirectory().equals(Environment.MEDIA_MOUNTED)) {//sd卡存在//再libs文件夹中导入afinal框架                    FinalHttp fh = new FinalHttp();                    //调用download方法开始下载                    //第一个参数这里是下载的路径（ "/mnt/sdcard/testapk.apk", //这是保存到本地的路径），第二个参数                    // true:断点续传 false:不断点续传（全新下载），第三个参数回                    HttpHandler
   
     handler = fh.download(Environment.getExternalStorageDirectory().getAbsolutePath() + "/phonesafe02.apk",                            String.valueOf(true),                            new AjaxCallBack() {                                @Override                                public void onLoading(long count, long current) {                                    tv.setText("下载进度：" + current + "/" + count);                                }                                public void onSuccess(File t) {                                    tv.setText(t == null ? "null" : t.getAbsoluteFile().toString());                                    //下载好了就安装应用apk                                    installapk(t);                                }                                //下载好了就安装应用apk                                private void installapk(File t) {                                    Intent intent = new Intent();                                    intent.setAction("android.intent.action.VIEW");                                    intent.addCategory("android.intent.categary.DEFAULT");                                    intent.setDataAndType(Uri.fromFile(t),"application/vnd.android.package-archive");                                    startActivity(intent);                                }                            });                    //调用stop()方法停止下载                    handler.stop();                } else {sd卡不存在                    Toast.makeText(getApplicationContext(), "请安装sd卡后再试", 0).show();                    return;                }            }        });        build.setNegativeButton("下次再说", new DialogInterface.OnClickListener() {            @Override            public void onClick(DialogInterface dialog, int which) {                //取消对话框，进入主页面                dialog.dismiss();                ;                enterhome();            }        });        build.show();    }    //进入主页面    private void enterhome() {        Intent intent = new Intent(this, HomeActivity.class);        startActivity(intent);        //关闭当前的activity---销毁了        finish();    }    private void checkUpdate() {        new Thread(new Runnable() {            @Override            public void run() {                long startTime = System.currentTimeMillis();//1970到现在的毫秒数                Message msg = Message.obtain();//给handler传数据用的                try {                    URL url = new URL(getString(R.string.uodateUrl));                    HttpURLConnection conn = (HttpURLConnection) url.openConnection();                    conn.setConnectTimeout(5000);                    conn.setRequestMethod("GET");                    int code = conn.getResponseCode();                    if (code == 200) {                        InputStream is = conn.getInputStream();//联网成功获取数据                        String result = Utils.readfromStream(is);//转换成string//json解析                        try {                            JSONObject obj = new JSONObject(result);                            //得到服务器的信息                            version = (String) obj.get("version");                            downloadUrl = (String) obj.get("url");                            desc = (String) obj.get("desc");                            //版本比较                            if (getVersionName().equals(version)) {//版本一样，不升级，直接进入主页                                msg.what = ENTER_HOME;                            } else {//提示更新，弹出dialog                                msg.what = ENTER_DIALOG;                            }                        } catch (JSONException e) {                            e.printStackTrace();                            msg.what = JSON_ERROR;                        }                    }                } catch (MalformedURLException e) {                    e.printStackTrace();                    msg.what = URL_ERROR;                } catch (IOException e) {                    e.printStackTrace();                    msg.what = NET_ERROR;                } finally {                    long endTime = System.currentTimeMillis();//1970到现在的毫秒数                    long dTime = endTime - startTime;                    if (dTime < 2000) {                        try {                            //睡两秒，加上请求网络的时间一共2秒                            Thread.sleep(2000 - dTime);                        } catch (InterruptedException e) {                            e.printStackTrace();                        }                    }                    handler.sendMessage(msg);                }            }        }).start();    }    //获取应用程序的版本名称    private String getVersionName() {        PackageManager pm = getPackageManager();//用来管理手机的apk        try {            PackageInfo info = pm.getPackageInfo(getPackageName(), 0);//得到apk功能清单文件            return info.versionName;        } catch (PackageManager.NameNotFoundException e) {            e.printStackTrace();            return "";        }    }}
   

/** * * Created by lambo on 2018/4/11. * 吧stream流转换成string */public class Utils extends Object {    //吧流转换成string    public  static String readfromStream(InputStream is) throws IOException {        ByteArrayOutputStream baos=new ByteArrayOutputStream();       byte[] buffer=new byte[1024];int len=-1;while((is.read(buffer))!=-1){baos.write(buffer,0,len);}is.close();String result=buffer.toString();baos.close();        return result;    }}

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