Android的常用代码片段，,px-dp转换 ```j
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Android的常用代码片段，,px-dp转换 ```j
px-dp转换 ```javapublic static int dip2px(Context context, float dpValue) {
final float scale = context.getResources().getDisplayMetrics().density; return (int) (dpValue * scale + 0.5f);}public static int px2dip(Context context, float pxValue) { final float scale = context.getResources().getDisplayMetrics().density; return (int) (pxValue / scale + 0.5f);}px-sp转换javapublic static int px2sp(Context context, float pxValue) {
final float fontScale = context.getResources().getDisplayMetrics().scaledDensity; return (int) (pxValue / fontScale + 0.5f);}public static int sp2px(Context context, float spValue) { final float fontScale = context.getResources().getDisplayMetrics().scaledDensity; return (int) (spValue * fontScale + 0.5f);}手机号码正则java public static final String REG_PHONE_CHINA = "^((13[0-9])|(15[^4,\D])|(18[0,5-9]))\d{8}$";邮箱正则java public static final String REG_EMAIL = "\w+([-+.]\w+)@\w+([-.]\w+)\.\w+([-.]\w+)*";时间java // 把一个毫秒数转化成时间字符串
// 格式为小时/分/秒/毫秒（如：24903600 –> 06小时55分03秒600毫秒）/** * @param millis * 要转化的毫秒数。 * @param isWhole * 是否强制全部显示小时/分/秒/毫秒。 * @param isFormat * 时间数字是否要格式化，如果true：少位数前面补全；如果false：少位数前面不补全。 * @return 返回时间字符串：小时/分/秒/毫秒的格式（如：24903600 --> 06小时55分03秒600毫秒）。 */public static String millisToString(long millis, boolean isWhole, boolean isFormat) { String h = ""; String m = ""; String s = ""; String mi = ""; if (isWhole) { h = isFormat ? "00小时" : "0小时"; m = isFormat ? "00分" : "0分"; s = isFormat ? "00秒" : "0秒"; mi = isFormat ? "00毫秒" : "0毫秒"; } long temp = millis; long hper = 60 * 60 * 1000; long mper = 60 * 1000; long sper = 1000; if (temp / hper > 0) { if (isFormat) { h = temp / hper < 10 ? "0" + temp / hper : temp / hper + ""; } else { h = temp / hper + ""; } h += "小时"; } temp = temp % hper; if (temp / mper > 0) { if (isFormat) { m = temp / mper < 10 ? "0" + temp / mper : temp / mper + ""; } else { m = temp / mper + ""; } m += "分"; } temp = temp % mper; if (temp / sper > 0) { if (isFormat) { s = temp / sper < 10 ? "0" + temp / sper : temp / sper + ""; } else { s = temp / sper + ""; } s += "秒"; } temp = temp % sper; mi = temp + ""; if (isFormat) { if (temp < 100 && temp >= 10) { mi = "0" + temp; } if (temp < 10) { mi = "00" + temp; } } mi += "毫秒"; return h + m + s + mi;}// 格式为小时/分/秒/毫秒（如：24903600 –> 06小时55分03秒）。/** * * @param millis * 要转化的毫秒数。 * @param isWhole * 是否强制全部显示小时/分/秒/毫秒。 * @param isFormat * 时间数字是否要格式化，如果true：少位数前面补全；如果false：少位数前面不补全。 * @return 返回时间字符串：小时/分/秒/毫秒的格式（如：24903600 --> 06小时55分03秒）。 */public static String millisToStringMiddle(long millis, boolean isWhole, boolean isFormat) { return millisToStringMiddle(millis, isWhole, isFormat, "小时", "分钟", "秒");}public static String millisToStringMiddle(long millis, boolean isWhole, boolean isFormat, String hUnit, String mUnit, String sUnit) { String h = ""; String m = ""; String s = ""; if (isWhole) { h = isFormat ? "00" + hUnit : "0" + hUnit; m = isFormat ? "00" + mUnit : "0" + mUnit; s = isFormat ? "00" + sUnit : "0" + sUnit; } long temp = millis; long hper = 60 * 60 * 1000; long mper = 60 * 1000; long sper = 1000; if (temp / hper > 0) { if (isFormat) { h = temp / hper < 10 ? "0" + temp / hper : temp / hper + ""; } else { h = temp / hper + ""; } h += hUnit; } temp = temp % hper; if (temp / mper > 0) { if (isFormat) { m = temp / mper < 10 ? "0" + temp / mper : temp / mper + ""; } else { m = temp / mper + ""; } m += mUnit; } temp = temp % mper; if (temp / sper > 0) { if (isFormat) { s = temp / sper < 10 ? "0" + temp / sper : temp / sper + ""; } else { s = temp / sper + ""; } s += sUnit; } return h + m + s;}// 把一个毫秒数转化成时间字符串。格式为小时/分/秒/毫秒（如：24903600 –> 06小时55分钟）/** * * @param millis * 要转化的毫秒数。 * @param isWhole * 是否强制全部显示小时/分。 * @param isFormat * 时间数字是否要格式化，如果true：少位数前面补全；如果false：少位数前面不补全。 * @return 返回时间字符串：小时/分/秒/毫秒的格式（如：24903600 --> 06小时55分钟）。 */public static String millisToStringShort(long millis, boolean isWhole, boolean isFormat) { String h = ""; String m = ""; if (isWhole) { h = isFormat ? "00小时" : "0小时"; m = isFormat ? "00分钟" : "0分钟"; } long temp = millis; long hper = 60 * 60 * 1000; long mper = 60 * 1000; long sper = 1000; if (temp / hper > 0) { if (isFormat) { h = temp / hper < 10 ? "0" + temp / hper : temp / hper + ""; } else { h = temp / hper + ""; } h += "小时"; } temp = temp % hper; if (temp / mper > 0) { if (isFormat) { m = temp / mper < 10 ? "0" + temp / mper : temp / mper + ""; } else { m = temp / mper + ""; } m += "分钟"; } return h + m;}// 把日期毫秒转化为字符串/** * @param millis * 要转化的日期毫秒数。 * @param pattern * 要转化为的字符串格式（如：yyyy-MM-dd HH:mm:ss）。 * @return 返回日期字符串。 */public static String millisToStringDate(long millis, String pattern) { SimpleDateFormat format = new SimpleDateFormat(pattern, Locale.getDefault()); return format.format(new Date(millis));}// 把日期毫秒转化为字符串（文件名）/** * @param millis * 要转化的日期毫秒数。 * @param pattern * 要转化为的字符串格式（如：yyyy-MM-dd HH:mm:ss）。 * @return 返回日期字符串（yyyy_MM_dd_HH_mm_ss）。 */public static String millisToStringFilename(long millis, String pattern) { String dateStr = millisToStringDate(millis, pattern); return dateStr.replaceAll("[- :]", "_");}// 转换当前时间为易用时间格式// 1小时内用，多少分钟前； 超过1小时，显示时间而无日期； 如果是昨天，则显示昨天 超过昨天再显示日期； 超过1年再显示年。public static long oneHourMillis = 60 * 60 * 1000; // 一小时的毫秒数public static long oneDayMillis = 24 * oneHourMillis; // 一天的毫秒数public static long oneYearMillis = 365 * oneDayMillis; // 一年的毫秒数public static String millisToLifeString(long millis) { long now = System.currentTimeMillis(); long todayStart = string2Millis(millisToStringDate(now, "yyyy-MM-dd"), "yyyy-MM-dd"); // 一小时内 if (now - millis <= oneHourMillis && now - millis > 0l) { String m = millisToStringShort(now - millis, false, false); return "".equals(m) ? "1分钟内" : m + "前"; } // 大于今天开始开始值，小于今天开始值加一天（即今天结束值） if (millis >= todayStart && millis <= oneDayMillis + todayStart) { return "今天 " + millisToStringDate(millis, "HH:mm"); } // 大于（今天开始值减一天，即昨天开始值） if (millis > todayStart - oneDayMillis) { return "昨天 " + millisToStringDate(millis, "HH:mm"); } long thisYearStart = string2Millis(millisToStringDate(now, "yyyy"), "yyyy"); // 大于今天小于今年 if (millis > thisYearStart) { return millisToStringDate(millis, "MM月dd日 HH:mm"); } return millisToStringDate(millis, "yyyy年MM月dd日 HH:mm");}// 字符串解析成毫秒数public static long string2Millis(String str, String pattern) { SimpleDateFormat format = new SimpleDateFormat(pattern, Locale.getDefault()); long millis = 0; try { millis = format.parse(str).getTime(); } catch (ParseException e) { Log.e("TAG", e.getMessage()); } return millis;}收集设备信息，用于信息统计分析java public static Properties collectDeviceInfo(Context context) {
Properties mDeviceCrashInfo = new Properties(); try { PackageManager pm = context.getPackageManager(); PackageInfo pi = pm.getPackageInfo(context.getPackageName(), PackageManager.GET_ACTIVITIES); if (pi != null) { mDeviceCrashInfo.put(VERSION_NAME, pi.versionName == null ? "not set" : pi.versionName); mDeviceCrashInfo.put(VERSION_CODE, pi.versionCode); } } catch (PackageManager.NameNotFoundException e) { Log.e(TAG, "Error while collect package info", e); } Field[] fields = Build.class.getDeclaredFields(); for (Field field : fields) { try { field.setAccessible(true); mDeviceCrashInfo.put(field.getName(), field.get(null)); } catch (Exception e) { Log.e(TAG, "Error while collect crash info", e); } } return mDeviceCrashInfo;}public static String collectDeviceInfoStr(Context context) { Properties prop = collectDeviceInfo(context); Set deviceInfos = prop.keySet(); StringBuilder deviceInfoStr = new StringBuilder("{\n"); for (Iterator iter = deviceInfos.iterator(); iter.hasNext();) { Object item = iter.next(); deviceInfoStr.append("\t\t\t" + item + ":" + prop.get(item) + ", \n"); } deviceInfoStr.append("}"); return deviceInfoStr.toString();}是否有SD卡javapublic static boolean haveSDCard() { return android.os.Environment.getExternalStorageState().equals( android.os.Environment.MEDIA_MOUNTED); }动态隐藏软键盘java @ TargetApi(Build.VERSION_CODES.CUPCAKE) public static void hideSoftInput(Activity activity) {
View view = activity.getWindow().peekDecorView(); if (view != null) { InputMethodManager inputmanger = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE); inputmanger.hideSoftInputFromWindow(view.getWindowToken(), 0); }}@ TargetApi(Build.VERSION_CODES.CUPCAKE)public static void hideSoftInput(Context context, EditText edit) { edit.clearFocus(); InputMethodManager inputmanger = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE); inputmanger.hideSoftInputFromWindow(edit.getWindowToken(), 0);}动态显示软键盘java @ TargetApi(Build.VERSION_CODES.CUPCAKE) public static void showSoftInput(Context context, EditText edit) {
edit.setFocusable(true); edit.setFocusableInTouchMode(true); edit.requestFocus(); InputMethodManager inputManager = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE); inputManager.showSoftInput(edit, 0);}动态显示或者是隐藏软键盘java @ TargetApi(Build.VERSION_CODES.CUPCAKE) public static void toggleSoftInput(Context context, EditText edit) {
edit.setFocusable(true); edit.setFocusableInTouchMode(true); edit.requestFocus(); InputMethodManager inputManager = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE); inputManager.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);}主动回到Home，后台运行java public static void goHome(Context context) {
Intent mHomeIntent = new Intent(Intent.ACTION_MAIN); mHomeIntent.addCategory(Intent.CATEGORY_HOME); mHomeIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED); context.startActivity(mHomeIntent);}获取状态栏高度java // 注意，要在onWindowFocusChanged中调用，在onCreate中获取高度为0 @ TargetApi(Build.VERSION_CODES.CUPCAKE) public static int getStatusBarHeight(Activity activity) {
Rect frame = new Rect(); activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame); return frame.top;}获取状态栏高度＋标题栏(ActionBar)高度java // (注意，如果没有ActionBar，那么获取的高度将和上面的是一样的，只有状态栏的高度) public static int getTopBarHeight(Activity activity) {
return activity.getWindow().findViewById(Window.ID_ANDROID_CONTENT).getTop();}获取MCC+MNC代码 (SIM卡运营商国家代码和运营商网络代码)java // 仅当用户已在网络注册时有效, CDMA 可能会无效（中国移动：46000 46002, 中国联通：46001,中国电信：46003） public static String getNetworkOperator(Context context) {
TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); return telephonyManager.getNetworkOperator();}返回移动网络运营商的名字java// (例：中国联通、中国移动、中国电信) 仅当用户已在网络注册时有效, CDMA 可能会无效)
public static String getNetworkOperatorName(Context context) { TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); return telephonyManager.getNetworkOperatorName();}返回移动终端类型java// PHONE_TYPE_NONE :0 手机制式未知 // PHONE_TYPE_GSM :1 手机制式为GSM，移动和联通 // PHONE_TYPE_CDMA :2 手机制式为CDMA，电信 // PHONE_TYPE_SIP:3 public static int getPhoneType(Context context) {
TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); return telephonyManager.getPhoneType();}判断手机连接的网络类型(2G,3G,4G)java// 联通的3G为UMTS或HSDPA，移动和联通的2G为GPRS或EGDE，电信的2G为CDMA，电信的3G为EVDO
public class Constants { /** * Unknown network class */ public static final int NETWORK_CLASS_UNKNOWN = 0; /** * wifi net work */ public static final int NETWORK_WIFI = 1; /** * "2G" networks */ public static final int NETWORK_CLASS_2_G = 2; /** * "3G" networks */ public static final int NETWORK_CLASS_3_G = 3; /** * "4G" networks */ public static final int NETWORK_CLASS_4_G = 4;}public static int getNetWorkClass(Context context) { TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); switch (telephonyManager.getNetworkType()) { case TelephonyManager.NETWORK_TYPE_GPRS: case TelephonyManager.NETWORK_TYPE_EDGE: case TelephonyManager.NETWORK_TYPE_CDMA: case TelephonyManager.NETWORK_TYPE_1xRTT: case TelephonyManager.NETWORK_TYPE_IDEN: return Constants.NETWORK_CLASS_2_G; case TelephonyManager.NETWORK_TYPE_UMTS: case TelephonyManager.NETWORK_TYPE_EVDO_0: case TelephonyManager.NETWORK_TYPE_EVDO_A: case TelephonyManager.NETWORK_TYPE_HSDPA: case TelephonyManager.NETWORK_TYPE_HSUPA: case TelephonyManager.NETWORK_TYPE_HSPA: case TelephonyManager.NETWORK_TYPE_EVDO_B: case TelephonyManager.NETWORK_TYPE_EHRPD: case TelephonyManager.NETWORK_TYPE_HSPAP: return Constants.NETWORK_CLASS_3_G; case TelephonyManager.NETWORK_TYPE_LTE: return Constants.NETWORK_CLASS_4_G; default: return Constants.NETWORK_CLASS_UNKNOWN; }}判断当前手机的网络类型(WIFI还是2,3,4G)java// 需要用到上面的方法
public static int getNetWorkStatus(Context context) { int netWorkType = Constants.NETWORK_CLASS_UNKNOWN; ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo(); if (networkInfo != null && networkInfo.isConnected()) { int type = networkInfo.getType(); if (type == ConnectivityManager.TYPE_WIFI) { netWorkType = Constants.NETWORK_WIFI; } else if (type == ConnectivityManager.TYPE_MOBILE) { netWorkType = getNetWorkClass(context); } } return netWorkType;}拨打电话javapublic static void call(Context context, String phoneNumber) {
context.startActivity(new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + phoneNumber)));}跳转至拨号界面javapublic static void callDial(Context context, String phoneNumber) {
context.startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse("tel:" + phoneNumber)));}发送短信javapublic static void sendSms(Context context, String phoneNumber, String content) {
Uri uri = Uri.parse("smsto:" + (TextUtils.isEmpty(phoneNumber) ? "" : phoneNumber));Intent intent = new Intent(Intent.ACTION_SENDTO, uri);intent.putExtra("sms_body", TextUtils.isEmpty(content) ? "" : content);context.startActivity(intent);}唤醒屏幕并解锁javapublic static void wakeUpAndUnlock(Context context) {
KeyguardManager km = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE); KeyguardManager.KeyguardLock kl = km.newKeyguardLock("unLock"); // 解锁 kl.disableKeyguard(); // 获取电源管理器对象 PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE); // 获取PowerManager.WakeLock对象,后面的参数|表示同时传入两个值,最后的是LogCat里用的Tag PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.SCREEN_DIM_WAKE_LOCK, "bright"); // 点亮屏幕 wl.acquire(); // 释放 wl.release();}//需要添加权限<uses-permission android:name="android.permission.WAKE_LOCK" /><uses-permission android:name="android.permission.DISABLE_KEYGUARD" />判断当前App处于前台还是后台状态javapublic static boolean isApplicationBackground(final Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE); @ SuppressWarnings("deprecation") List<ActivityManager.RunningTaskInfo> tasks = am.getRunningTasks(1); if (!tasks.isEmpty()) { ComponentName topActivity = tasks.get(0).topActivity; if (!topActivity.getPackageName().equals(context.getPackageName())) { return true; } } return false;}//需要添加权限<uses-permission
android:name="android.permission.GET_TASKS" />判断当前手机是否处于锁屏(睡眠)状态javapublic static boolean isSleeping(Context context) {
KeyguardManager kgMgr = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE); boolean isSleeping = kgMgr.inKeyguardRestrictedInputMode(); return isSleeping;}判断当前是否有网络连接javapublic static boolean isOnline(Context context) {
ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Activity.CONNECTIVITY_SERVICE); NetworkInfo info = manager.getActiveNetworkInfo(); if (info != null && info.isConnected()) { return true; } return false;}判断当前是否是WIFI连接状态javapublic static boolean isWifiConnected(Context context) {
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo wifiNetworkInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI); if (wifiNetworkInfo.isConnected()) { return true; } return false;}安装APKjavapublic static void installApk(Context context, File file) {
Intent intent = new Intent(); intent.setAction("android.intent.action.VIEW"); intent.addCategory("android.intent.category.DEFAULT"); intent.setType("application/vnd.android.package-archive"); intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive"); intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); context.startActivity(intent);}判断当前设备是否为手机javapublic static boolean isPhone(Context context) {
TelephonyManager telephony = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); if (telephony.getPhoneType() == TelephonyManager.PHONE_TYPE_NONE) { return false; } else { return true; }}获取当前设备宽高，单位pxjava@ SuppressWarnings("deprecation") public static int getDeviceWidth(Context context) {
WindowManager manager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); return manager.getDefaultDisplay().getWidth();}@ SuppressWarnings("deprecation")public static int getDeviceHeight(Context context) { WindowManager manager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); return manager.getDefaultDisplay().getHeight();}获取当前设备的IMEI，需要与上面的isPhone()一起使用java@ TargetApi(Build.VERSION_CODES.CUPCAKE) public static String getDeviceIMEI(Context context) {
String deviceId; if (isPhone(context)) { TelephonyManager telephony = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); deviceId = telephony.getDeviceId(); } else { deviceId = Settings.Secure.getString(context.getContentResolver(), Settings.Secure.ANDROID_ID); } return deviceId;}获取当前设备的MAC地址javapublic static String getMacAddress(Context context) {
String macAddress; WifiManager wifi = (WifiManager) context.getSystemService(Context.WIFI_SERVICE); WifiInfo info = wifi.getConnectionInfo(); macAddress = info.getMacAddress(); if (null == macAddress) { return ""; } macAddress = macAddress.replace(":", ""); return macAddress;}获取当前程序的版本号java public static String getAppVersion(Context context) {
String version = "0"; try { version = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).versionName; } catch (PackageManager.NameNotFoundException e) { e.printStackTrace(); } return version;}```
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