其他常用工具类

判断网络情况：

/**
     * 检测网络是否连接,如果连接，判断连接方式
     * 
     * @return
     */
    public static int getNetworkState() {
        boolean flag = false;
        // 得到网络连接信息
        ConnectivityManager manager = (ConnectivityManager) MainApplication
                .getContext().getSystemService(Context.CONNECTIVITY_SERVICE);
        // 去进行判断网络是否连接
        if (manager.getActiveNetworkInfo() != null) {
            flag = manager.getActiveNetworkInfo().isAvailable();
        }
        if (!flag) {
            return NONET;
        } else {
            State gprs = manager
                    .getNetworkInfo(ConnectivityManager.TYPE_MOBILE).getState();
            State wifi = manager.getNetworkInfo(ConnectivityManager.TYPE_WIFI)
                    .getState();

            // 判断为wifi状态下才加载广告，如果是GPRS手机网络则不加载！
            if (wifi == State.CONNECTED || wifi == State.CONNECTING) {
                // Toast.makeText(this, "wifi is open! wifi",
                // Toast.LENGTH_SHORT).show();
                return WIFI;
            }

            if (gprs == State.CONNECTED || gprs == State.CONNECTING) {
                // Toast.makeText(this, "wifi is open! gprs",
                // Toast.LENGTH_SHORT).show();
                return GPRS;
            }
            return NONET;
            // isNetworkAvailable();
        }

        // return flag;
    }

判断手机是否安装了某个应用：

/**
     * 判断手机是否安装某个应用
     * 
     * @param context
     * @param appPackageName
     *            应用包名
     * @return true：安装，false：未安装
     */
    public static boolean isApplicationAvilible(Context context,
            String appPackageName) {
        try {
            PackageManager packageManager = context.getPackageManager();// 获取packagemanager
            List<PackageInfo> pinfo = packageManager.getInstalledPackages(0);// 获取所有已安装程序的包信息
            if (pinfo != null) {
                for (int i = 0; i < pinfo.size(); i++) {
                    String pn = pinfo.get(i).packageName;
                    if (appPackageName.equals(pn)) {
                        return true;
                    }
                }
            }
        } catch (Exception e) {
            return false;
        }
        return false;
    }

判断文字相似度：

/**
     * 计算两个字符串的相似度
     * 
     * @param str1
     * @param str2
     * @return 相似度最大为1(相同字符串)，最小为0
     */
    public static float levenshtein(String str1, String str2) {
        // 计算两个字符串的长度。
        int len1 = str1.length();
        int len2 = str2.length();
        // 建立上面说的数组，比字符长度大一个空间
        int[][] dif = new int[len1 + 1][len2 + 1];
        // 赋初值，步骤B。
        for (int a = 0; a <= len1; a++) {
            dif[a][0] = a;
        }
        for (int a = 0; a <= len2; a++) {
            dif[0][a] = a;
        }
        // 计算两个字符是否一样，计算左上的值
        int temp;
        for (int i = 1; i <= len1; i++) {
            for (int j = 1; j <= len2; j++) {
                if (str1.charAt(i - 1) == str2.charAt(j - 1)) {
                    temp = 0;
                } else {
                    temp = 1;
                }
                // 取三个值中最小的
                dif[i][j] = min(dif[i - 1][j - 1] + temp, dif[i][j - 1] + 1,
                        dif[i - 1][j] + 1);
            }
        }
        // System.out.println("字符串\"" + str1 + "\"与\"" + str2 + "\"的比较");
        // // 取数组右下角的值，同样不同位置代表不同字符串的比较
        // System.out.println("差异步骤：" + dif[len1][len2]);
        // 计算相似度
        float similarity = 1 - (float) dif[len1][len2]
                / Math.max(str1.length(), str2.length());
        // System.out.println("相似度：" + similarity);
        return similarity;
    }

 判断外存是否可用：

/**
     * Checks if external storage is available for read and write
     */
    public static boolean isExternalStorageWritable() {

        String state = Environment.getExternalStorageState();
        if (Environment.MEDIA_MOUNTED.equals(state)) {
            return true;

        }
        return false;
    }

得到屏幕长宽（单位pix）：

DisplayMetrics dm = new DisplayMetrics();
context.getWindowManager().getDefaultDisplay().getMetrics(dm);
int widthPixels = dm.widthPixels;// 1280
int heightPixels = dm.heightPixels;// 752

 得到外存或者sd存储的路径：

/**
	 * get sd card path by reflecting.also usable when api is 23
	 * 
	 * @param mContext
	 * @param is_removale  false inner storage;true outer storage.
	 * @return
	 */
	private static String getStoragePath(Context mContext, boolean is_removale) {

		StorageManager mStorageManager = (StorageManager) mContext
				.getSystemService(Context.STORAGE_SERVICE);
		Class<?> storageVolumeClazz = null;
		try {
			storageVolumeClazz = Class
					.forName("android.os.storage.StorageVolume");
			Method getVolumeList = mStorageManager.getClass().getMethod(
					"getVolumeList");
			Method getPath = storageVolumeClazz.getMethod("getPath");
			Method isRemovable = storageVolumeClazz.getMethod("isRemovable");
			Object result = getVolumeList.invoke(mStorageManager);
			final int length = Array.getLength(result);
			for (int i = 0; i < length; i++) {
				Object storageVolumeElement = Array.get(result, i);
				String path = (String) getPath.invoke(storageVolumeElement);
				boolean removable = (Boolean) isRemovable
						.invoke(storageVolumeElement);
				if (is_removale == removable) {
					return path;
				}
			}
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (InvocationTargetException e) {
			e.printStackTrace();
		} catch (NoSuchMethodException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		}
		return null;
	}

 得到当前api的level：

int apiLevel = Build.VERSION.SDK_INT;