{"id":1,"date":"2016-08-02T16:44:31","date_gmt":"2016-08-02T08:44:31","guid":{"rendered":"http:\/\/www.bookcard.net\/wordpress\/?p=1"},"modified":"2018-01-16T16:27:30","modified_gmt":"2018-01-16T08:27:30","slug":"android_altimeter","status":"publish","type":"post","link":"https:\/\/www.bookcard.net\/wordpress\/android_altimeter\/","title":{"rendered":"Android\u9ad8\u5ea6\u8a08"},"content":{"rendered":"

\u8a2d\u8a08\u624b\u6a5f\u9ad8\u5ea6\u8a08!\u5916\u51fa\u65c5\u904a\u5fc5\u5099!
\n\u5229\u7528\u624b\u6a5f\u7684\u6c23\u58d3\u50b3\u611f\u5668,\u8a08\u7b97\u7576\u524d\u6d77\u62d4\u9ad8\u5ea6!
\n\u5b89\u684c\u624b\u6a5f\u7684\u901a\u5e38\u5e36\u6709\u6c23\u58d3\u7684\u76e3\u807d\u5668
\n1.\u7372\u53d6\u611f\u6e2c\u5668\u7ba1\u7406\u5668
\nSensor_Manager = (SensorManager) context.getSystemService(Context.SENSOR_SERVICE);
\n2.\u5224\u65b7\u662f\u5426\u6709\u6c23\u58d3\u8a08,\u9019\u500b\u5224\u65b7\u5f88\u7a2e\u8981,\u5982\u904e\u8fd4\u56de\u5247\u4ee3\u8868\u6c92\u6709\u53ef\u7528\u7684\u611f\u6e2c\u5668!
\nif(Sensor_Manager.getSensorList(Sensor.TYPE_PRESSURE).size() == 0)
\nreturn false;
\n3.\u7372\u53d6\u9ed8\u8a8d\u7684\u6c23\u58d3\u8a08
\nPressure_Sensor = Sensor_Manager.getDefaultSensor(Sensor.TYPE_PRESSURE);
\n\u6216\u8005\u7372\u53d6\u7684\u9996\u500b\u6c23\u58d3\u8a08
\nPressure_Sensor = Sensor_Manager.getSensorList(Sensor.TYPE_PRESSURE).get(0);
\n4.\u751f\u6210\u6c23\u76e3\u807d\u5668
\nPressure_Listener = new PressureListener();
\n5.\u8a3b\u518a\u611f\u6e2c\u5668\u4e8b\u4ef6
\nSensor_Manager.registerListener(Pressure_Listener, Pressure_Sensor, SensorManager.SENSOR_DELAY_UI);
\n6.\u5275\u5efa\u6c23\u58d3\u7684\u76e3\u807d\u5668\u985e,\u7528\u65bc\u7372\u53d6\u6c23\u58d3!
\nstatic class PressureListener implements SensorEventListener{
\n7.\u6c23\u58d3\u76e4\u6539\u8b8a
\n@Override
\npublic void onSensorChanged(SensorEvent event)
\n{
\nPressure = event.values[0]; \/\/\u7372\u53d6\u6c23\u58d3
\n}
\n}
\n8.\u6c23\u58d3\u8f49\u9ad8\u5ea6
\n\u6bcf\u4e0a\u534712\u7c73,\u6c23\u58d3\u8a08\u4e2d\u7684\u6c34\u9280\u67f1\u4e0b\u964d1\u6beb\u7c73,
\nhPa\u662f\u767e\u5e15
\n\u5728\u6d77\u5e73\u9762\u7684\u5e73\u5747\u6c23\u58d3 \u7d04\u70ba1013.25\u767e\u5e15\u65af\u5361\uff08760\u6beb\u7c73\u6c34\u9280\u67f1\uff09,\u9019\u500b\u503c\u4e5f\u88ab\u7a31\u70ba\u6a19\u6e96\u5927\u6c23\u58d3
\n1\u767e\u5e15=1\u6beb\u5df4=3\/4\u6beb\u7c73\u6c34\u9280\u67f1
\n\u6240\u4ee5901HPA(\u6c23\u58d3)
\n901HPA=901*3\/4=682.5MM\u6c34\u9280\u67f1
\n760-682.5=77.5MM
\n77.5*12=930\u7c73
\npublic static float PressureToAltitude(float Pressure)
\n{
\nfloat Altitude = 0;\/\/ \u9ad8\u5ea6
\nfloat PRESSURE_STANDARD_ATMOSPHERE = 1013.25f;\/\/ \u5728\u6d77\u5e73\u9762\u7684\u5e73\u5747\u6c23\u58d3(\u767e\u5e15\u65af\u5361)<\/p>\n

\/\/ \u8f49\u63db\u70ba\u6c34\u9280\u67f1
\nAltitude = (float) (44330000f* (1f- Math.pow( Pressure\/PRESSURE_STANDARD_ATMOSPHERE, 1.0f\/5255.0f )));
\nreturn Altitude;
\n}<\/p>\n

10.\u9000\u51fa\u61c9\u7528\u6642\u91cb\u653e\u611f\u6e2c\u5668\u76e3\u807d
\nSensor_Manager.unregisterListener(Pressure_Listener);<\/p>\n

\/\/\u7c73\u8f49\u82f1\u5c3a
\nstatic float m2ft(float m)
\n{
\nfloat ft=0;
\nft = m * 3.2808398950131f;
\nreturn ft;
\n}<\/p>\n

\/\/\u7c73\u8f49\u82f1\u5c3a
\nstatic float ft2m(float ft)
\n{
\nfloat m=0;
\nm = ft * 0.3048f;
\nreturn m;
\n}
\n\u6c92\u6709\u6c23\u58d3\u50b3\u611f\u5668\u5247\u901a\u904eGPS\u78ba\u5b9a\u9ad8\u5ea6,\u5f8c\u7e8c.<\/p>\n