我需要添加一个摇功能,将刷新我的Android应用程序。
我所找到的所有文档都涉及实现SensorListener,但Eclipse告诉我它已被弃用,并建议使用SensorEventListener。
有人知道如何创建这个震动控制器吗?
我需要添加一个摇功能,将刷新我的Android应用程序。
我所找到的所有文档都涉及实现SensorListener,但Eclipse告诉我它已被弃用,并建议使用SensorEventListener。
有人知道如何创建这个震动控制器吗?
当前回答
你可以用地震法。这里可以找到一个例子。
其他回答
这里还有另一个实现,它是基于这里的一些技巧以及来自Android开发人员网站的代码。
MainActivity.java
public class MainActivity extends Activity {
private ShakeDetector mShakeDetector;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ShakeDetector initialization
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mShakeDetector = new ShakeDetector(new OnShakeListener() {
@Override
public void onShake() {
// Do stuff!
}
});
}
@Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(mShakeDetector, mAccelerometer, SensorManager.SENSOR_DELAY_UI);
}
@Override
protected void onPause() {
mSensorManager.unregisterListener(mShakeDetector);
super.onPause();
}
}
ShakeDetector.java
package com.example.test;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
public class ShakeDetector implements SensorEventListener {
// Minimum acceleration needed to count as a shake movement
private static final int MIN_SHAKE_ACCELERATION = 5;
// Minimum number of movements to register a shake
private static final int MIN_MOVEMENTS = 2;
// Maximum time (in milliseconds) for the whole shake to occur
private static final int MAX_SHAKE_DURATION = 500;
// Arrays to store gravity and linear acceleration values
private float[] mGravity = { 0.0f, 0.0f, 0.0f };
private float[] mLinearAcceleration = { 0.0f, 0.0f, 0.0f };
// Indexes for x, y, and z values
private static final int X = 0;
private static final int Y = 1;
private static final int Z = 2;
// OnShakeListener that will be notified when the shake is detected
private OnShakeListener mShakeListener;
// Start time for the shake detection
long startTime = 0;
// Counter for shake movements
int moveCount = 0;
// Constructor that sets the shake listener
public ShakeDetector(OnShakeListener shakeListener) {
mShakeListener = shakeListener;
}
@Override
public void onSensorChanged(SensorEvent event) {
// This method will be called when the accelerometer detects a change.
// Call a helper method that wraps code from the Android developer site
setCurrentAcceleration(event);
// Get the max linear acceleration in any direction
float maxLinearAcceleration = getMaxCurrentLinearAcceleration();
// Check if the acceleration is greater than our minimum threshold
if (maxLinearAcceleration > MIN_SHAKE_ACCELERATION) {
long now = System.currentTimeMillis();
// Set the startTime if it was reset to zero
if (startTime == 0) {
startTime = now;
}
long elapsedTime = now - startTime;
// Check if we're still in the shake window we defined
if (elapsedTime > MAX_SHAKE_DURATION) {
// Too much time has passed. Start over!
resetShakeDetection();
}
else {
// Keep track of all the movements
moveCount++;
// Check if enough movements have been made to qualify as a shake
if (moveCount > MIN_MOVEMENTS) {
// It's a shake! Notify the listener.
mShakeListener.onShake();
// Reset for the next one!
resetShakeDetection();
}
}
}
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// Intentionally blank
}
private void setCurrentAcceleration(SensorEvent event) {
/*
* BEGIN SECTION from Android developer site. This code accounts for
* gravity using a high-pass filter
*/
// alpha is calculated as t / (t + dT)
// with t, the low-pass filter's time-constant
// and dT, the event delivery rate
final float alpha = 0.8f;
// Gravity components of x, y, and z acceleration
mGravity[X] = alpha * mGravity[X] + (1 - alpha) * event.values[X];
mGravity[Y] = alpha * mGravity[Y] + (1 - alpha) * event.values[Y];
mGravity[Z] = alpha * mGravity[Z] + (1 - alpha) * event.values[Z];
// Linear acceleration along the x, y, and z axes (gravity effects removed)
mLinearAcceleration[X] = event.values[X] - mGravity[X];
mLinearAcceleration[Y] = event.values[Y] - mGravity[Y];
mLinearAcceleration[Z] = event.values[Z] - mGravity[Z];
/*
* END SECTION from Android developer site
*/
}
private float getMaxCurrentLinearAcceleration() {
// Start by setting the value to the x value
float maxLinearAcceleration = mLinearAcceleration[X];
// Check if the y value is greater
if (mLinearAcceleration[Y] > maxLinearAcceleration) {
maxLinearAcceleration = mLinearAcceleration[Y];
}
// Check if the z value is greater
if (mLinearAcceleration[Z] > maxLinearAcceleration) {
maxLinearAcceleration = mLinearAcceleration[Z];
}
// Return the greatest value
return maxLinearAcceleration;
}
private void resetShakeDetection() {
startTime = 0;
moveCount = 0;
}
// (I'd normally put this definition in it's own .java file)
public interface OnShakeListener {
public void onShake();
}
}
下面是一个示例代码。 把这些放到你的活动课上:
/* put this into your activity class */
private SensorManager mSensorManager;
private float mAccel; // acceleration apart from gravity
private float mAccelCurrent; // current acceleration including gravity
private float mAccelLast; // last acceleration including gravity
private final SensorEventListener mSensorListener = new SensorEventListener() {
public void onSensorChanged(SensorEvent se) {
float x = se.values[0];
float y = se.values[1];
float z = se.values[2];
mAccelLast = mAccelCurrent;
mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
float delta = mAccelCurrent - mAccelLast;
mAccel = mAccel * 0.9f + delta; // perform low-cut filter
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
};
@Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
mSensorManager.unregisterListener(mSensorListener);
super.onPause();
}
把这个添加到你的onCreate方法中:
/* do this in onCreate */
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
mAccel = 0.00f;
mAccelCurrent = SensorManager.GRAVITY_EARTH;
mAccelLast = SensorManager.GRAVITY_EARTH;
然后你可以在你的应用程序中任何你想要的地方询问“mAccel”当前加速度,独立于轴,并从静态加速度(如重力)中清除。 大概是。如果没有移动,则为0,如果设备震动,则为>2。
根据评论-测试这一点:
if (mAccel > 12) {
Toast toast = Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG);
toast.show();
}
注:
The accelometer should be deactivated onPause and activated onResume to save resources (CPU, Battery). The code assumes we are on planet Earth ;-) and initializes the acceleration to earth gravity. Otherwise you would get a strong "shake" when the application starts and "hits" the ground from free-fall. However, the code gets used to the gravitation due to the low-cut filter and would work also on other planets or in free space, once it is initialized. (you never know how long your application will be in use...;-)
我已经尝试了几种实现,但我想分享一下我自己的实现。 它以g力为单位进行阈值计算。这让我们更容易理解发生了什么,同时也设置了一个好的阈值。
它只是记录G力的增加,如果超过阈值就触发侦听器。它不使用任何方向阈值,因为如果你只是想记录一个好的震动,你真的不需要这个。
当然,您需要在Activity中对这个侦听器进行标准的注册和un -注册。
此外,为了检查您需要的阈值,我推荐以下应用程序(我没有以任何方式连接到该应用程序)
public class UmitoShakeEventListener implements SensorEventListener {
/**
* The gforce that is necessary to register as shake. (Must include 1G
* gravity)
*/
private final float shakeThresholdInGForce = 2.25F;
private final float gravityEarth = SensorManager.GRAVITY_EARTH;
private OnShakeListener listener;
public void setOnShakeListener(OnShakeListener listener) {
this.listener = listener;
}
public interface OnShakeListener {
public void onShake();
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// ignore
}
@Override
public void onSensorChanged(SensorEvent event) {
if (listener != null) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
float gX = x / gravityEarth;
float gY = y / gravityEarth;
float gZ = z / gravityEarth;
//G-Force will be 1 when there is no movement. (gravity)
float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ);
if (gForce > shakeThresholdInGForce) {
listener.onShake();
}
}
}
}
你可以用地震法。这里可以找到一个例子。
你可能想试试开源tinybus。有了它,震动检测就像这样简单。
public class MainActivity extends Activity {
private Bus mBus;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// Create a bus and attach it to activity
mBus = TinyBus.from(this).wire(new ShakeEventWire());
}
@Subscribe
public void onShakeEvent(ShakeEvent event) {
Toast.makeText(this, "Device has been shaken",
Toast.LENGTH_SHORT).show();
}
@Override
protected void onStart() {
super.onStart();
mBus.register(this);
}
@Override
protected void onStop() {
mBus.unregister(this);
super.onStop();
}
}
它采用地震仪进行振动检测。