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Android传感器API之:方向SensorOrientation传感器功能实现与源码分享

继续明确一下空间坐标系的三个方向:x 方向就是手机的水平方向,右为正;y 方向就是手机的水平垂直方向,前为正;z 方向就是手机的空间垂直方向,天空的方向为正,地球的方向为负。方向角的定义是手机y轴 水平......

继续明确一下空间坐标系的三个方向:

x 方向就是手机的水平方向,右为正;

y 方向就是手机的水平垂直方向,前为正;

z 方向就是手机的空间垂直方向,天空的方向为正,地球的方向为负。

方向角的定义是手机y轴 水平面上的投影 与 正北方向的夹角。 (值得范围是 0 ~ 359 其中0=North, 90=East, 180=South, 270=West)

倾斜角的定义是手机y轴 与水平面的夹角 (手机z轴向y轴方向移动为正 ,值得范围是 -180 ~ 180)

旋转角的定义是手机x轴 与水平面的夹角 (手机x轴离开z轴方向为正, 值得范围是 -90 ~ 90)

也就是说,当你把手机水平放置在桌面上(屏幕向上)且手机指向正北(Y轴方向),此时传感器获得的xyz三个值应该都为0。

如下是Rexsee实现的方向传感器功能源码。我会把Rexsee扩展的全部传感器源码都陆续贴出来,但是首先需要知道,并不是所有的Android手机都支持方向传感器。。比如说乐Phone,好像就是加速度、重力和光线,方向和磁场貌似都不支持。

[代码] [HTML]代码

/*

* Copyright (C) 2011 The Rexsee Open Source Project

*

* Licensed under the Rexsee License, Version 1.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.rexsee.com/CN/legal/license.html

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

package rexsee.sensor;

import rexsee.core.browser.JavascriptInterface;

import rexsee.core.browser.RexseeBrowser;

import android.content.Context;

import android.hardware.Sensor;

import android.hardware.SensorEvent;

import android.hardware.SensorEventListener;

import android.hardware.SensorManager;

public class RexseeSensorOrientation implements JavascriptInterface {

public static final String INTERFACE_NAME = "Orientation";

@Override

public String getInterfaceName() {

return mBrowser.application.resources.prefix + INTERFACE_NAME;

}

@Override

public JavascriptInterface getInheritInterface(RexseeBrowser childBrowser) {

return this;

}

@Override

public JavascriptInterface getNewInterface(RexseeBrowser childBrowser) {

return new RexseeSensorOrientation(childBrowser);

}

public static final String EVENT_ONORIENTATIONCHANGED = "onOrientationChanged";

private final Context mContext;

private final RexseeBrowser mBrowser;

private final SensorManager mSensorManager;

private SensorEventListener mSensorListener;

private final Sensor mSensor;

private int mRate = SensorManager.SENSOR_DELAY_NORMAL;

private int mCycle = 100; //milliseconds

private int mEventCycle = 100; //milliseconds

private float mAccuracyX = 0;

private float mAccuracyY = 0;

private float mAccuracyZ = 0;

private long lastUpdate = -1;

private long lastEvent = -1;

private float x = -999f;

private float y = -999f;

private float z = -999f;

public RexseeSensorOrientation(RexseeBrowser browser) {

mContext = browser.getContext();

mBrowser = browser;

browser.eventList.add(EVENT_ONORIENTATIONCHANGED);

mSensorManager = (SensorManager) mContext.getSystemService(Context.SENSOR_SERVICE);

mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION);

mSensorListener = new SensorEventListener() {

@Override

public void onAccuracyChanged(Sensor sensor, int accuracy) {

}

@Override

public void onSensorChanged(SensorEvent event) {

if (event.sensor.getType() != Sensor.TYPE_ORIENTATION) return;

long curTime = System.currentTimeMillis();

if (lastUpdate == -1 || (curTime - lastUpdate) > mCycle) {

lastUpdate = curTime;

float lastX = x;

float lastY = y;

float lastZ = z;

x = event.values[SensorManager.DATA_X];

y = event.values[SensorManager.DATA_Y];

z = event.values[SensorManager.DATA_Z];

if (lastEvent == -1 || (curTime - lastEvent) > mEventCycle) {

if (

(mAccuracyX >= 0 && Math.abs(x - lastX) > mAccuracyX)

|| (mAccuracyY >= 0 && Math.abs(y - lastY) > mAccuracyY)

|| (mAccuracyZ >= 0 && Math.abs(z - lastZ) > mAccuracyZ)

) {

lastEvent = curTime;

mBrowser.eventList.run(EVENT_ONORIENTATIONCHANGED);

}

}

}

}

};

}

public String getLastKnownX() {

return (x == -999) ? "null" : String.valueOf(x);

}

public String getLastKnownY() {

return (y == -999) ? "null" : String.valueOf(y);

}

public String getLastKnownZ() {

return (z == -999) ? "null" : String.valueOf(z);

}

public void setRate(String rate) {

mRate = SensorRate.getInt(rate);

}

public String getRate() {

return SensorRate.getString(mRate);

}

public void setCycle(int milliseconds) {

mCycle = milliseconds;

}

public int getCycle() {

return mCycle;

}

public void setEventCycle(int milliseconds) {

mEventCycle = milliseconds;

}

public int getEventCycle() {

return mEventCycle;

}

public void setAccuracy(float x, float y, float z) {

mAccuracyX = x;

mAccuracyY = y;

mAccuracyZ = z;

}

public float getAccuracyX() {

return mAccuracyX;

}

public float getAccuracyY() {

return mAccuracyY;

}

public float getAccuracyZ() {

return mAccuracyZ;

}

public boolean isReady() {

return (mSensor == null) ? false : true;

}

public void start() {

if (isReady()) {

mSensorManager.registerListener(mSensorListener, mSensor, mRate);

} else {

mBrowser.exception(getInterfaceName(), "Orientation sensor is not found.");

}

}

public void stop() {

if (isReady()) {

mSensorManager.unregisterListener(mSensorListener);

}

}

}