如何检查光量?
How to check amount of light?
我用 Camera2API
工作,如果外面光线不足,我需要禁用拍照功能 ...
我考虑过,当用户使用标准相机时,他设置为闪光灯(自动模式)。
如果我没理解错的话,相机会使用某种传感器来检测光量,如果光量不够,闪光灯就会工作。
如何连接这个传感器?
您可以使用类似于此处列出的代码的内容:
https://developer.android.com/guide/topics/sensors/sensors_environment.html
像这样修改它以与光传感器一起工作:
public class SensorActivity extends Activity implements SensorEventListener {
private SensorManager mSensorManager;
private Sensor mLight;
@Override
public final void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Get an instance of the sensor service, and use that to get an instance of
// a particular sensor.
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mLight= mSensorManager.getDefaultSensor(Sensor.TYPE_LIGHT);
}
@Override
public final void onAccuracyChanged(Sensor sensor, int accuracy) {
// Do something here if sensor accuracy changes.
}
@Override
public final void onSensorChanged(SensorEvent event) {
float luminosity = event.values[0];
// Do something with this sensor data.
}
@Override
protected void onResume() {
// Register a listener for the sensor.
super.onResume();
mSensorManager.registerListener(this, mLight, SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
// Be sure to unregister the sensor when the activity pauses.
super.onPause();
mSensorManager.unregisterListener(this);
}
}
我用 Camera2API
工作,如果外面光线不足,我需要禁用拍照功能 ...
我考虑过,当用户使用标准相机时,他设置为闪光灯(自动模式)。
如果我没理解错的话,相机会使用某种传感器来检测光量,如果光量不够,闪光灯就会工作。
如何连接这个传感器?
您可以使用类似于此处列出的代码的内容:
https://developer.android.com/guide/topics/sensors/sensors_environment.html
像这样修改它以与光传感器一起工作:
public class SensorActivity extends Activity implements SensorEventListener {
private SensorManager mSensorManager;
private Sensor mLight;
@Override
public final void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Get an instance of the sensor service, and use that to get an instance of
// a particular sensor.
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mLight= mSensorManager.getDefaultSensor(Sensor.TYPE_LIGHT);
}
@Override
public final void onAccuracyChanged(Sensor sensor, int accuracy) {
// Do something here if sensor accuracy changes.
}
@Override
public final void onSensorChanged(SensorEvent event) {
float luminosity = event.values[0];
// Do something with this sensor data.
}
@Override
protected void onResume() {
// Register a listener for the sensor.
super.onResume();
mSensorManager.registerListener(this, mLight, SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
// Be sure to unregister the sensor when the activity pauses.
super.onPause();
mSensorManager.unregisterListener(this);
}
}