36个经典

/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 + "" ;

 

    }