36个Android开发常用代码片段
36个Android开发常用代码片段
拨打电话
public 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
public static void callDial(Context context, String phoneNumber) { context.startActivity( new Intent(Intent.ACTION_DIAL, Uri.parse( "tel:" + phoneNumber))); } |
发送短信
public 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
public 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
public 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
public 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
public 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
public 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APK
public 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
public 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px
@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
@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
public 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
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; } |
收集设备信息,用于信息统计分析
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
public static boolean haveSDCard() { return android.os.Environment.getExternalStorageState().equals( android.os.Environment.MEDIA_MOUNTED); } |
动态隐藏软键盘
@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
@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
@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
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
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
(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)
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
(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
- 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)
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)
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; } |
px-dp转换
public 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
public 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); } |
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 + "" ; }
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