手機安全衛士的學習（1）

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今天學習的主要是SplashActivity頁面的初始化，其中涉及很多知識點

1 擷取包名 擷取版本號碼資訊

2 檢查升級，以及利用第三方工具對json資料的解析

3 Thread線程和message的運用

package com.djf.mobilesafty;import java.io.IOException;import java.io.InputStream;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import org.json.JSONException;import org.json.JSONObject;import com.djf.mobilesafty.utils.StreamTools;import android.app.Activity;import android.content.Intent;import android.content.pm.PackageInfo;import android.content.pm.PackageManager;import android.content.pm.PackageManager.NameNotFoundException;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.text.Annotation;import android.util.Log;import android.view.Menu;import android.view.MenuItem;import android.view.animation.AlphaAnimation;import android.widget.TextView;import android.widget.Toast;public class SplashActivity extends Activity {    protected static final String TAG = "SplashActivity";    protected static final int ENTER_HOME = 0;    protected static final int SHOW_DIALOG = 1;    protected static final int URL_ERROR = 2;    protected static final int NET_ERROR = 3;    protected static final int JSON_ERROR = 4;    private TextView tv_splash_verison;    private String description;    private String apkurl;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv_splash_verison = (TextView) findViewById(R.id.tv_splash_verison);        tv_splash_verison.setText("版本號碼：" + getVersionName());        AlphaAnimation aa = new AlphaAnimation(0.2f, 1.0f);        aa.setDuration(500);        findViewById(R.layout.activity_main).startAnimation(aa);        // 檢查升級        checkupdate();    }    private Handler handler = new Handler() {        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {            case ENTER_HOME:// 進入首頁面                EnterHome();                break;            case SHOW_DIALOG:// 顯示對話方塊                Log.i(TAG, "顯示升級對話方塊");                break;            case URL_ERROR:// url錯誤                EnterHome();                Toast.makeText(getApplicationContext(), "url錯誤", 0).show();                break;            case NET_ERROR:// 網路錯誤                EnterHome();                Toast.makeText(SplashActivity.this, "網路錯誤", 0).show();                break;            case JSON_ERROR:// json解析出錯                EnterHome();                Toast.makeText(SplashActivity.this, "json解析出錯", 0).show();                break;            default:                break;            }        }    };    protected void EnterHome() {        // TODO Auto-generated method stub        Intent intent = new Intent(this, HomeActivity.class);        startActivity(intent);        // 關閉當前頁面        finish();    };    /**     * 檢查是否需要升級     */    private void checkupdate() {        // http://125.39.51.195:8080/updatinfo.html        new Thread() {            public void run() {                Message msg = Message.obtain();                long starttime = System.currentTimeMillis();                try {                    URL url = new URL(getString(R.string.serverurl));                    HttpURLConnection connection = (HttpURLConnection) url                            .openConnection();                    connection.setRequestMethod("GET");                    connection.setReadTimeout(4000);                    int code = connection.getResponseCode();                    if (code == 200) {                        InputStream in = connection.getInputStream();                        // 把流轉化成string                        String result = StreamTools.readFromStream(in);                        Log.i(TAG, "連網成功" + result);                        // json解析                        JSONObject obj = new JSONObject(result);                        // 得到伺服器的版本資訊                        String version = (String) obj.get("version");                        description = (String) obj.get("description");                        apkurl = (String) obj.get("apkurl");                        // 校正是否有新版本                        if (getVersionName().equals(version)) {                            // 版本一致                            msg.what = ENTER_HOME;                        } else {                            // 版本不一致                            msg.what = SHOW_DIALOG;                        }                    }                } catch (MalformedURLException e) {                    msg.what = URL_ERROR;                    e.printStackTrace();                } catch (IOException e) {                    msg.what = NET_ERROR;                    e.printStackTrace();                } catch (JSONException e) {                    // TODO Auto-generated catch block                    msg.what = JSON_ERROR;                    e.printStackTrace();                } finally {                    long endtime = System.currentTimeMillis();                    long dtime = endtime - starttime;                    if (dtime < 2000) {                        try {                            Thread.sleep(2000 - dtime);                        } catch (InterruptedException e) {                            // TODO Auto-generated catch block                            e.printStackTrace();                        }                    }                    handler.sendMessage(msg);                }            };        }.start();    }    /**     * 得到應用程式資訊的版本     */    private String getVersionName() {        PackageManager pManager = getPackageManager();        try {            PackageInfo info = pManager.getPackageInfo(getPackageName(), 0);            return info.versionName;        } catch (NameNotFoundException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        return "";    }}

 

手機安全衛士的學習（1）