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）
浏览数：18 /
时间：2015年06月11日
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
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