android - sensor manager
TRANSCRIPT
Android –Sensor Manager
Yong Heui Cho @ Mokwon University
Some of slides are referred to:[1] Nitin Ramchandani, Android OS, slideshare.
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Smart Device M2M
10. Arduino+Android - BT+IoTN11. Arduino - Pressure Sensor
12. Android – Sensor Message
13. BT+IoTN Project - Con-cept
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Application
Application Structure
Activity
Context
OS
Resources
Service
lifecycle
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Activity Lifecycle
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Lifecycle Comparison
Run Terminate
onCreate() onDestroy()
onStart() onStop()
onResume() onPause()
onRestart() -
onRestoreInstanceState() onSaveInstanceState()
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Summary of Lifecycle
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Android vs. Windowstype Android Windows
CPU optimal fast
battery small power supply
memory mobile DRAMsmall
DRAMlarge
message handler message (Message) or action (String) message (int)
termination app lifecycle permanent
function call call & proceed call & wait or call & proceed
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MVC Components
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Android Msg Handler
• Message: containing a description and arbitrary data object
• Runnable: a command that can be executed• Handler: allows you to send and process
Message and Runnable • Looper: used to run a message loop for a thread
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Concept of Multithread
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Android Rules• Do not block the UI thread (or
main thread).• Do not access the Android UI
toolkit from outside the UI thread.
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Event Listener• Interface to process specific
events
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PhoneStateListner• Monitors changes in specific telephony
states on the device, including service state, signal strength, message waiting indicator (voicemail).
Activity
Context
PhoneStateListener
OS
TelephonyManager
listen()
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Broadcast Receiver
• An Intent-based publish-subscribe mechanism.
• Great for listening system events such as SMS messages.
□ Courtesy to Everything of Android, slideshare.
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BR vs. Listenertype BroadcastReceiver Listener
goal class for Intentsclass or interface for Intents & oth-
ers
message mostly global mes-sages
mostly specific messages
period discontinuous re-ception
frequent (or continu-ous) reception
construction static (manifest) or dynamic dynamic only
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Android & Sensors
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Sensor Manager• SensorManager
Context.getSystemService(SENSOR_SERVICE)
• Sensor SensorManager.getDefaultSensor(Sensor.TYPE_XXX)
• SensorManager.registerListener(SEL, Sensor, int samplingPeriodUs)
• SensorManager.unregisterListener(SEL)
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SensorEventListener
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Type of Sensors