Android开发-常用工具方法（dp转成px、网络是否可用、是否3G网络、Gps是否打开、判断手机号码等）

Android开发常用工具方法（CommonTools）

在发开Android应用过程中，我们往往添加一个Utils包放置一些帮助方法类（这也是很好的Android开发习惯），这样大大方便了开发时的调取操作、也使得软件维护、更新更为便捷，以下就是我常用的几个util类：有关于网络的、文件操作的等等！ 

public class CommonTools {/** * 短暂显示Toast消息 *  * @param context * @param message */public static void showShortToast(Context context, String message) {LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);View view = inflater.inflate(R.layout.custom_toast, null);TextView text = (TextView) view.findViewById(R.id.toast_message);text.setText(message);Toast toast = new Toast(context);toast.setDuration(Toast.LENGTH_SHORT);toast.setGravity(Gravity.BOTTOM, 0, 300);toast.setView(view);toast.show();}/** * 根据手机分辨率从dp转成px *  * @param context * @param dpValue * @return */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) - 15;}/** * 获取手机状态栏高度 *  * @param context * @return */public static int getStatusBarHeight(Context context) {Class<?> c = null;Object obj = null;java.lang.reflect.Field field = null;int x = 0;int statusBarHeight = 0;try {c = Class.forName("com.android.internal.R$dimen");obj = c.newInstance();field = c.getField("status_bar_height");x = Integer.parseInt(field.get(obj).toString());statusBarHeight = context.getResources().getDimensionPixelSize(x);return statusBarHeight;} catch (Exception e) {e.printStackTrace();}return statusBarHeight;}/** * 判断手机号码*/public static boolean isMobileNO(String mobiles){Pattern pattern = Pattern.compile("^((13[0-9])|(15[^4,\\D])|(18[0,5-9]))\\d{8}$");  Matcher matcher = pattern.matcher(mobiles);  return matcher.matches();}}

关于网络判断的类NetworkUtils

public class NetworkUtils {/** * 网络是否可用 *  * @param activity * @return */public static boolean isNetworkAvailable(Context context) {ConnectivityManager connectivity = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);if (connectivity == null) {} else {NetworkInfo[] info = connectivity.getAllNetworkInfo();if (info != null) {for (int i = 0; i < info.length; i++) {if (info[i].getState() == NetworkInfo.State.CONNECTED) {return true;}}}}return false;}/** * 网络连接提示 *  * @param context * @return */public static void networkStateTips(Context context) {if (!isNetworkAvailable(context)) {CommonTools.showShortToast(context, "网络故障，请先检查网络连接");}}/** * Gps是否打开 *  * @param context * @return */public static boolean isGpsEnabled(Context context) {LocationManager locationManager = ((LocationManager) context.getSystemService(Context.LOCATION_SERVICE));List<String> accessibleProviders = locationManager.getProviders(true);return accessibleProviders != null && accessibleProviders.size() > 0;}/** * wifi是否打开 */public static boolean isWifiEnabled(Context context) {ConnectivityManager mgrConn = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);TelephonyManager mgrTel = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);return ((mgrConn.getActiveNetworkInfo() != null && mgrConn.getActiveNetworkInfo().getState() == NetworkInfo.State.CONNECTED) || mgrTel.getNetworkType() == TelephonyManager.NETWORK_TYPE_UMTS);}/** * 判断当前网络是否是wifi网络 * if(activeNetInfo.getType()==ConnectivityManager.TYPE_MOBILE) { //判断3G网 *  * @param context * @return boolean */public static boolean isWifi(Context context) {ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();if (activeNetInfo != null&& activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) {return true;}return false;}/** * 判断当前网络是否是3G网络 *  * @param context * @return boolean */public static boolean is3G(Context context) {ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();if (activeNetInfo != null&& activeNetInfo.getType() == ConnectivityManager.TYPE_MOBILE) {return true;}return false;}}

文件操作类FileUtils

public class FileUtils {    private final static String t = "FileUtils";    // Used to validate and display valid form names.    public static final String VALID_FILENAME = "[ _\\-A-Za-z0-9]*.x[ht]*ml";    // Storage paths    public static final String FORMS_PATH = Environment.getExternalStorageDirectory() + "/odk/forms/";    public static final String INSTANCES_PATH = Environment.getExternalStorageDirectory() + "/odk/instances/";    public static final String CACHE_PATH = Environment.getExternalStorageDirectory() + "/odk/.cache/";    public static final String TMPFILE_PATH = CACHE_PATH + "tmp.jpg";        public static ArrayList<String> getValidFormsAsArrayList(String path) {        ArrayList<String> formPaths = new ArrayList<String>();        File dir = new File(path);        if (!storageReady()) {            return null;        }        if (!dir.exists()) {            if (!createFolder(path)) {                return null;            }        }        File[] dirs = dir.listFiles();        for (int i = 0; i < dirs.length; i++) {          // skip all the directories          if (dirs[i].isDirectory())            continue;                      String formName = dirs[i].getName();          formPaths.add(dirs[i].getAbsolutePath());        }        return formPaths;    }    public static ArrayList<String> getFoldersAsArrayList(String path) {        ArrayList<String> mFolderList = new ArrayList<String>();        File root = new File(path);        if (!storageReady()) {            return null;        }        if (!root.exists()) {            if (!createFolder(path)) {                return null;            }        }        if (root.isDirectory()) {            File[] children = root.listFiles();            for (File child : children) {                boolean directory = child.isDirectory();                if (directory) {                    mFolderList.add(child.getAbsolutePath());                }            }        }        return mFolderList;    }    public static boolean deleteFolder(String path) {        // not recursive        if (path != null && storageReady()) {            File dir = new File(path);            if (dir.exists() && dir.isDirectory()) {                File[] files = dir.listFiles();                for (File file : files) {                    if (!file.delete()) {                        Log.i(t, "Failed to delete " + file);                    }                }            }            return dir.delete();        } else {            return false;        }    }    public static boolean createFolder(String path) {        if (storageReady()) {            boolean made = true;            File dir = new File(path);            if (!dir.exists()) {                made = dir.mkdirs();            }            return made;        } else {            return false;        }    }    public static boolean deleteFile(String path) {        if (storageReady()) {            File f = new File(path);            return f.delete();        } else {            return false;        }    }    public static byte[] getFileAsBytes(File file) {        byte[] bytes = null;        InputStream is = null;        try {            is = new FileInputStream(file);            // Get the size of the file            long length = file.length();            if (length > Integer.MAX_VALUE) {                Log.e(t, "File " + file.getName() + "is too large");                return null;            }            // Create the byte array to hold the data            bytes = new byte[(int) length];            // Read in the bytes            int offset = 0;            int read = 0;            try {                while (offset < bytes.length && read >= 0) {                    read = is.read(bytes, offset, bytes.length - offset);                    offset += read;                }            } catch (IOException e) {                Log.e(t, "Cannot read " + file.getName());                e.printStackTrace();                return null;            }            // Ensure all the bytes have been read in            if (offset < bytes.length) {                try {                    throw new IOException("Could not completely read file " + file.getName());                } catch (IOException e) {                    e.printStackTrace();                    return null;                }            }            return bytes;        } catch (FileNotFoundException e) {            Log.e(t, "Cannot find " + file.getName());            e.printStackTrace();            return null;        } finally {            // Close the input stream            try {                is.close();            } catch (IOException e) {                Log.e(t, "Cannot close input stream for " + file.getName());                e.printStackTrace();                return null;            }        }    }    public static boolean storageReady() {        String cardstatus = Environment.getExternalStorageState();        if (cardstatus.equals(Environment.MEDIA_REMOVED)                || cardstatus.equals(Environment.MEDIA_UNMOUNTABLE)                || cardstatus.equals(Environment.MEDIA_UNMOUNTED)                || cardstatus.equals(Environment.MEDIA_MOUNTED_READ_ONLY)) {            return false;        } else {            return true;        }    }    public static String getMd5Hash(File file) {        try {            // CTS (6/15/2010) : stream file through digest instead of handing it the byte[]            MessageDigest md = MessageDigest.getInstance("MD5");            int chunkSize = 256;            byte[] chunk = new byte[chunkSize];            // Get the size of the file            long lLength = file.length();            if (lLength > Integer.MAX_VALUE) {                Log.e(t, "File " + file.getName() + "is too large");                return null;            }            int length = (int) lLength;            InputStream is = null;            is = new FileInputStream(file);            int l = 0;            for (l = 0; l + chunkSize < length; l += chunkSize) {                is.read(chunk, 0, chunkSize);                md.update(chunk, 0, chunkSize);            }            int remaining = length - l;            if (remaining > 0) {                is.read(chunk, 0, remaining);                md.update(chunk, 0, remaining);            }            byte[] messageDigest = md.digest();            BigInteger number = new BigInteger(1, messageDigest);            String md5 = number.toString(16);            while (md5.length() < 32)                md5 = "0" + md5;            is.close();            return md5;        } catch (NoSuchAlgorithmException e) {            Log.e("MD5", e.getMessage());            return null;        } catch (FileNotFoundException e) {            Log.e("No Cache File", e.getMessage());            return null;        } catch (IOException e) {            Log.e("Problem reading from file", e.getMessage());            return null;        }             }}

Written in the last：在这篇博客中我会慢慢总结我经常用到的util类，谢谢！

2014.2.16