我准备在这件事上受到羞辱,但我不知道出了什么问题。我只是在玩 Android 开发,只是在制作一个简单的应用程序,它将加速度计打印到 TextView。
创建 SensorEventListener 时,出现语法错误
(说 ; 是完成语句所必需的)
有问题的确切代码:
private SensorEventListener listener = new SensorEventListener() {
public void onSensorChanged(SensorEvent e) {
if (e.sensor.getType()==Sensor.TYPE_ACCELEROMETER) {
xAxis = e.values[0];
yAxis = e.values[1];
zAxis = e.values[2];
if (xThreshold > xAxis || yThreshold > yAxis || zThreshold > zAxis) {
alertUser(values);
}
else {
nonAlert(values);
}
}
}
}
如果需要,这里是完整的代码
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
public class TiltMeter {
private SensorManager mgr = null;
private double xAxis = 0;
private double yAxis = 0;
private double zAxis = 0;
private double xThreshold = 0;
private double yThreshold = 0;
private double zThreshold = 0;
public TiltMeter(Context context, double xThreshold, double yThreshold, double zThreshold, TiltMeter.Callback cb) {
this.xThreshold = xThreshold;
this.yThreshold = yThreshold;
this.zThreshold = zThreshold;
mgr = (SensorManager)context.getSystemService(Context.SENSOR_SERVICE);
mgr.registerListener(listener, mgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_UI);
}
private SensorEventListener listener = new SensorEventListener() {
public void onSensorChanged(SensorEvent e) {
if (e.sensor.getType()==Sensor.TYPE_ACCELEROMETER) {
xAxis = e.values[0];
yAxis = e.values[1];
zAxis = e.values[2];
if (xThreshold > xAxis || yThreshold > yAxis || zThreshold > zAxis) {
alertUser(values);
}
else {
nonAlert(values);
}
}
}
}
public void close() {
mgr.unregisterListener(listener);
}
public interface Callback {
double[] alertUser(double[] data);
double[] nonAlert(double[] data);
}
}
这是活动:
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class TiltMeterActivity extends Activity
implements TiltMeter.Callback {
/** Called when the activity is first created. */
TiltMeter tiltMeter = null;
TextView tvXAxis;
TextView tvYAxis;
TextView tvZAxis;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tvXAxis = (TextView)findViewById(R.id.txtXAxisValue);
tvYAxis = (TextView)findViewById(R.id.txtYAxisValue);
tvZAxis = (TextView)findViewById(R.id.txtZAxisValue);
}
@Override
public void onDestroy() {
super.onDestroy();
tiltMeter.close();
}
public double[] alertUser(double[] data) {
tvXAxis.setText(Double.toString(data[0]));
tvYAxis.setText(Double.toString(data[1]));
tvZAxis.setText(Double.toString(data[3]));
return null;
}
public double[] nonAlert(double[] data) {
tvXAxis.setText(Double.toString(data[0]));
tvYAxis.setText(Double.toString(data[1]));
tvZAxis.setText(Double.toString(data[3]));
return null;
}
}
谢谢你的帮助。这是我的参考: 参考项目