public class CommonUtil {          public static boolean hasSDCard() {              String status = Environment.getExternalStorageState();          return status.equals(Environment.MEDIA_MOUNTED);      }          /**       * 获取最大内存       *        * @return       */      public static long getMaxMemory() {              return Runtime.getRuntime().maxMemory() / 1024;      }          /**       * 检查网络       *        * @param context       * @return       */      public static boolean checkNetState(Context context) {              boolean netstate = false;          ConnectivityManager connectivity = (ConnectivityManager) context                  .getSystemService(Context.CONNECTIVITY_SERVICE);          if (connectivity != null) {                  NetworkInfo[] info = connectivity.getAllNetworkInfo();              if (info != null) {                  for (int i = 0; i < info.length; i++) {                          if (info[i].getState() == NetworkInfo.State.CONNECTED) {                              netstate = true;                          break;                      }                  }              }          }          return netstate;      }          public static void showToast(Context context, String tip) {              Toast.makeText(context, tip, Toast.LENGTH_SHORT).show();      }          public static DisplayMetrics metric = new DisplayMetrics();          /**       * 得到屏幕高度       *        * @param context       * @return       */      public static int getScreenHeight(Activity context) {              context.getWindowManager().getDefaultDisplay().getMetrics(metric);          return metric.heightPixels;      }          /**       * 得到屏幕宽度       *        * @param context       * @return       */      public static int getScreenWidth(Activity context) {              context.getWindowManager().getDefaultDisplay().getMetrics(metric);          return metric.widthPixels;      }          /**       * 根据手机的分辨率从 dp 的单位 转成为 px(像素)       */          public static int dip2px(Context context, float dpValue) {          final float scale = context.getResources().getDisplayMetrics().density;          return (int) (dpValue * scale + 0.5f);      }          /**       * 根据手机的分辨率从 px(像素) 的单位 转成为 dp       */      public static int px2dip(Context context, float pxValue) {              final float scale = context.getResources().getDisplayMetrics().density;          return (int) (pxValue / scale + 0.5f);      }          /**       * 查询手机内非系统应用       *        * @param context       * @return       */      public static List<PackageInfo> getAllApps(Context context) {              List<PackageInfo> apps = new ArrayList<PackageInfo>();          PackageManager pManager = context.getPackageManager();          // 获取手机内所有应用          List<PackageInfo> paklist = pManager.getInstalledPackages(0);          for (int i = 0; i < paklist.size(); i++) {              PackageInfo pak = (PackageInfo) paklist.get(i);              // 判断是否为非系统预装的应用程序              if ((pak.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) <= 0) {                  // customs applications                  apps.add(pak);              }          }          return apps;      }          public static Bitmap zoomBitmap(Bitmap bitmap, int width, int height) {          int w = bitmap.getWidth();          int h = bitmap.getHeight();          Matrix matrix = new Matrix();          float scaleWidth = ((float) width / w);          float scaleHeight = ((float) height / h);          matrix.postScale(scaleWidth, scaleHeight);          Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);          return newbmp;      }          /**       * 获取版本号和版本次数       *        * @param context       * @return       */      public static String getVersionCode(Context context, int type) {              try {                  PackageInfo pi = context.getPackageManager().getPackageInfo(                      context.getPackageName(), 0);              if (type == 1) {                      return String.valueOf(pi.versionCode);              } else {                      return pi.versionName;              }          } catch (NameNotFoundException e) {                  e.printStackTrace();              return null;          }      }          // 通过Service的类名来判断是否启动某个服务      public static boolean messageServiceIsStart(              List<ActivityManager.RunningServiceInfo> mServiceList,              String className) {              for (int i = 0; i < mServiceList.size(); i++) {              if (className.equals(mServiceList.get(i).service.getClassName())) {                      return true;              }          }          return false;      }  }