Android------sensor

<span id="Label3"></p><p><p>The Android system provides support for the Sensor.<br>Developing an application sensor is simple, just registering a listener for the specified listener.</p></p><p><p><br>Steps:<br>1. Call the Getsystemservice (context.sensor_service) method of the Context to get the Sensormanager object, and the Sensormanager object represents the System's sensor management Service<br>2. Call Sensormanager's getdefaultsensor (int Type) method to get the sensor of the specified type<br>3. Usually choose to call Sensormanager's Registerlistener () in the Activity's onresume () method to register the listener for the specified Sensor.<br>The program can get the data returned by the sensor by implementing the Listener.</p></p><p><p>Sensormanager provides a method for registering sensors: registerlistener (sensoreventlistener listener,sensor sensor, int rate):<br>Parameters:<br>Listener<br>Monitor the Sensor's listener. The listener needs to implement the Sensoreventlistener interface<br>Sensor: Sensor Object<br>rate: specifies how often to get sensor Data.<br>There are several frequencies:</p></p><p><p>Sensormanager.sensor_delay_fastest:<br>The fastest, least latency, is recommended for applications that rely specifically on sensor Data.</p></p><p><p>Sensormanager.sensor_delay_game:<br>The frequency for the Game. This frequency is suitable for use in general practical applications.</p></p><p><p>Sensormanager.sensor_delay_normal:<br>Normal Frequency. General real-time requirements are not particularly high for applications that are suitable for use.</p></p><p><p>Sensormanager.sensor_delay_ui:<br>The frequency for the normal user interface. Used in ordinary small programs.</p></p><p><p></p></p><p><p></p></p><p><p>Commonly used sensors for android:</p></p><p><p>direction, Magnetic field, temperature, light, pressure.<br></p></p><p><p></p></p><p><p></p></p><p><p></p></p><p><p>Layout file:</p></p><p><p><br></p></p><pre class="html" name="code"><linearlayout xmlns:android= "http://schemas.android.com/apk/res/android" xmlns:tools= "http// Schemas.android.com/tools "android:layout_width=" fill_parent "android:layout_height=" fill_parent "android:orienta tion= "vertical" android:paddingbottom= "@dimen/activity_vertical_margin" android:paddingleft= "@dimen/activity_ Horizontal_margin "android:paddingright=" @dimen/activity_horizontal_margin "android:paddingtop=" @dimen/activity_ Vertical_margin "tools:context=" com.example.sensor.MainActivity "> <textview android:layout_width=" Fill _parent "android:layout_height=" wrap_content "android:text=" @string/orientation "/> <edittext android:id= "@+id/etorientation" android:layout_width= "fill_parent" android:layout_height= "wrap_content" android:cursorvisible= "false" android:editable= "false"/> <textview android:layout_width= "fill _parent "android:layout_height=" wrap_content " android:text= "@string/magnetic"/> <edittext android:id= "@+id/etmagnetic" android:layout_width= "f Ill_parent "android:layout_height=" wrap_content "android:cursorvisible=" false "android:editable=" Fals E "/> <textview android:layout_width=" fill_parent "android:layout_height=" wrap_content "android oid:text= "@string/temperature"/> <edittext android:id= "@+id/ettemerature" android:layout_width= "fi Ll_parent "android:layout_height=" wrap_content "android:cursorvisible=" false "android:editable=" False "/> <textview android:layout_width=" fill_parent "android:layout_height=" wrap_content "andro id:text= "@string/light"/> <edittext android:id= "@+id/etlight" android:layout_width= "fill_parent" android:layout_height= "wrap_content" android:cursorvisible= "false" android:editable= "false"/> & Lt TextView AndroId:layout_width= "fill_parent" android:layout_height= "wrap_content" android:text= "@string/pressure"/> <edittext android:id= "@+id/etpressure" android:layout_width= "fill_parent" android:layout_height= "w Rap_content "android:cursorvisible=" false "android:editable=" false "/></linearlayout></pre><p><p><br></p></p><p><p>Activity:</p></p><p><p></p></p><pre class="html" name="code">public class Mainactivity extends Activity implements Sensoreventlistener {//definition Sensormanagersensormanager Msensormanager;//direction edittext etorientation;//magnetic field edittext etmagnetic;//temperature edittext ettemerature;//light edittext etlight;// Pressure edittext etpressure; @Overrideprotected void onCreate (Bundle Savedinstancestate) {super.oncreate ( savedinstancestate); setcontentview (r.layout.activity_main); etorientation = (EditText) Findviewbyid ( r.id.etorientation); etmagnetic = (EditText) Findviewbyid (r.id.etmagnetic); ettemerature = (EditText) Findviewbyid ( r.id.ettemerature); etlight = (EditText) Findviewbyid (r.id.etlight); etpressure = (EditText) Findviewbyid ( R.id.etpressure);//get Sensor Management Service Msensormanager = (sensormanager) Getsystemservice (sensor_service);} @Overrideprotected void Onresume () {super.onresume ();//register listener Msensormanager.registerlistener for direction sensor (this, Msensormanager.getdefaultsensor (sensor.type_orientation), sensormanager.sensor_delay_game);// Register the Listener Msensormanager.registerlistener for the System's magnetic field sensor (THIS,MSENSORMANAGER.GEtdefaultsensor (sensor.type_magnetic_field), sensormanager.sensor_delay_game);// Register the listener for the System's temperature sensor Msensormanager.registerlistener (this, Msensormanager.getdefaultsensor (sensor.type_ambient_ temperature), sensormanager.sensor_delay_game);//for The System's optical sensor Register listener Msensormanager.registerlistener (this, Msensormanager.getdefaultsensor (sensor.type_light), sensormanager.sensor_delay_game);// Register the Listener Msensormanager.registerlistener (this,msensormanager.getdefaultsensor (sensor.type_pressure) for the system's pressure sensor, sensormanager.sensor_delay_game);} @Overrideprotected void OnStop () {msensormanager.unregisterlistener (this); super.onstop ();} @Overrideprotected void OnPause () {msensormanager.unregisterlistener (this); super.onpause ();} The following are the methods that implement the Sensoreventlistener interface that must be implemented @overridepublic void onsensorchanged (sensorevent event) {float values[] = Event.values;int SensorType = Event.sensor.getType (); StringBuilder sb = new StringBuilder (); switch (sensortype) {//direction sensor case SENSOR.TYPE_ORIENTATION:SB = new StringBuilder () Sb.append ("the angle of rotation around the z axis:"); sB.append (values[0]); sb.append ("the angle of the x-axis turned:"), sb.append (values[1]), sb.append ("the angle that goes around the y axis:"); sb.append (values[2) ); etorientation.settext (sb.tostring ()); break;//magnetic field sensor Case SENSOR.TYPE_MAGNETIC_FIELD:SB = new StringBuilder (); Sb.append ("angle in x direction:"), sb.append (values[0]), sb.append ("angle in \ny direction:"), sb.append (values[1]), sb.append ("angle in \nz direction:" ); sb.append (values[2]); etmagnetic.settext (sb.tostring ()); break;//temperature sensor Case SENSOR.TYPE_AMBIENT_TEMPERATURE:SB = New StringBuilder (); sb.append ("current temperature:"); sb.append (values[0]); ettemerature.settext (sb.tostring ()); break;// Light sensor Case SENSOR.TYPE_LIGHT:SB = new StringBuilder () sb.append ("the intensity of the current light is:"); sb.append (values[0]); Etlight.settext ( Sb.tostring ()); break;//pressure sensor Case SENSOR.TYPE_PRESSURE:SB = new StringBuilder () sb.append ("current pressure:"); sb.append ( values[0]); etpressure.settext (sb.tostring ()); break;default:break;}} Callback this method when the sensor accuracy changes @overridepublic void onaccuracychanged (sensor sensor, int Accuracy) {//TODO auto-generated method stub} }</pre><p><p><br></p></p><p><p></p></p><p><p>Android------sensor</p></p></span>