定期任务(通过蓝牙发送消息)

Question

在我的移动机器人项目中，有两个伺服电机可以在两个平面上旋转相机，我想在我的android应用程序中通过旋转智能手机来控制它们(通过智能手机加速度计的偏航/俯仰/滚转读数)。

为此，我必须通过蓝牙向Arduino发送关于这三个角度的数据。例如，示例数据包看起来像：

"Y:100，p:20，R:45"式中[Y-偏航，P-俯仰，R-滚转]。

负责将此命令/消息发送到Arduino->bl.sendData("A:"+String.format("%.0f",azimut) + ",P:" + String.format("%.0f",pitch) + ",R:" + String.format("%.0f",roll) + ".");的代码

我希望此消息每隔200毫秒循环发送一次(当我参与此"活动"时)->(现在每次单击"SEND"：D按钮时都会发送)。

我还必须提到，除了这条消息到Arduino应用程序，当我在同一活动中触摸虚拟操纵杆以控制我的移动机器人的方向时，发送另一条消息，我希望发送这两条消息之间没有冲突)

那我怎么才能拿到呢？一些示例代码？

这是安卓工作室的代码(关于此活动)：

package com.samplecompass;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.content.Context;
import android.content.Intent;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements SensorEventListener {
private cBluetooth bl = null;
private String address = "00:11:35:94:61:19";
private StringBuilder sb = new StringBuilder();
private Button send;

Float azimutF;
Float pitchF;
Float pitchMax=0.0f;
Float azimut;  // View to draw a compass
Float pitch;
Float roll;
int zgoda=0;
int zgodaa=1;
int znak=1;
private TextView mPitch;


private SensorManager mSensorManager;
Sensor accelerometer;
Sensor magnetometer;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bl = new cBluetooth(this, mHandler);
bl.checkBTState();
mPitch = (TextView) findViewById(R.id.Pitch);
send = (Button) findViewById(R.id.send);
mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
accelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
magnetometer = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);

send.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
zgodaa=0;
//bl.sendData("Hello");
}
});
}
private final Handler mHandler =  new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case cBluetooth.BL_NOT_AVAILABLE:
Log.d(cBluetooth.TAG, "Bluetooth is not available. Exit");
Toast.makeText(getBaseContext(), "Bluetooth is not available", Toast.LENGTH_SHORT).show();
finish();
break;
case cBluetooth.BL_INCORRECT_ADDRESS:
Log.d(cBluetooth.TAG, "Incorrect MAC address");
Toast.makeText(getBaseContext(), "Incorrect Bluetooth address", Toast.LENGTH_SHORT).show();
break;
case cBluetooth.BL_REQUEST_ENABLE:
Log.d(cBluetooth.TAG, "Request Bluetooth Enable");
BluetoothAdapter.getDefaultAdapter();
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, 1);
break;
case cBluetooth.BL_SOCKET_FAILED:
Toast.makeText(getBaseContext(), "Socket failed", Toast.LENGTH_SHORT).show();
finish();
break;
case cBluetooth.RECIEVE_MESSAGE:                                                    // if message is recieved
byte[] readBuf = (byte[]) msg.obj;
String strIncom = new String(readBuf, 0, msg.arg1);                 // create string from bytes array
sb.append(strIncom);                                                // append string
int endOfLineIndex = sb.indexOf("rn");                            // determine the end-of-line
if (endOfLineIndex > 0) {                                           // if end-of-line,
String sbprint = sb.substring(0, endOfLineIndex);               // extract string
sb.delete(0, sb.length());                                      // and clear
//txtArduino.setText("Data from Arduino: " + sbprint);          // update TextView
}
break;
}
};
};
protected void onResume() {
super.onResume();
bl.BT_Connect(address);
//bl.sendData("Hello World");
mSensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
mSensorManager.registerListener(this, magnetometer, SensorManager.SENSOR_DELAY_UI);
}
protected void onPause() {
super.onPause();
bl.BT_onPause();
mSensorManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {  }
float[] mGravity;
float[] mGeomagnetic;
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER)
mGravity = event.values;
if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD)
mGeomagnetic = event.values;
if (mGravity != null && mGeomagnetic != null) {
float R[] = new float[9];
float I[] = new float[9];
boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
if (success) {
float orientation[] = new float[3];
SensorManager.getOrientation(R, orientation);
if(zgoda==0) {
azimutF = -orientation[0] * 360 / (2 * 3.14159f) - 90;
pitchF  = orientation[1]*360/(2*3.14159f);
}
zgoda=1;
azimut =  -orientation[0]*360/(2*3.14159f) - azimutF; // orientation contains: azimut, pitch and roll
pitch  =  -1*(orientation[1]*360/(2*3.14159f));
if(pitchMax<pitch){ pitchMax=pitch;}
/**if (Math.round(pitch) == 0) {
if(znak==1) znak=-1;
else if(znak==-1) znak=1;
}**/
roll   =  -orientation[2]*360/(2*3.14159f);
mPitch.setText(String.valueOf("Azimut: " + String.format("%.0f",azimut)) + String.valueOf("Znak:" + pitchMax) + String.valueOf("Pitch:" + String.format("%.0f",pitch)) + String.valueOf("Roll:" + String.format("%.0f",roll)));
if(zgodaa== 0) {bl.sendData("A:"+String.format("%.0f",azimut) + ",P:" + String.format("%.0f",pitch) + ",R:" + String.format("%.0f",roll) + ".");}
zgodaa=1;
}
}
}
}

Answer 1

@jdv谢谢你的帮助，现在我知道怎么做了->

public class MainActivity extends Activity implements SensorEventListener {
private Handler handler
...
protected void onCreate(Bundle savedInstanceState) {  
handler = new Handler();     
...
}
Runnable mStatusChecker = new Runnable() {
@Override
public void run() {
try {
bl.sendData("A:"+i+String.format("%.0f",azimut) + ",P:" + String.format("%.0f",pitch) + ",R:" + String.format("%.0f",roll) + ".");; //this function can change value of mInterval.
} finally {
// 100% guarantee that this always happens, even if
// your update method throws an exception
handler.postDelayed(mStatusChecker, 1000);
}

}
};
void startRepeatingTask() {
mStatusChecker.run();
}
void stopRepeatingTask() {
mHandler.removeCallbacks(mStatusChecker);
}
private final Handler mHandler =  new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case cBluetooth.BL_OK:
startRepeatingTask();
Toast.makeText(getBaseContext(), "BL_OK", 
Toast.LENGTH_SHORT).show();
break;
}
}
}

所以我在连接蓝牙时调用函数startRepeatingTask();，因为在其他情况下会弹出其他错误。

但现在我有另一个问题，我不想创建新的主题，所以当我按下智能手机的主页按钮和后退按钮时，你能告诉我哪个功能是呼叫吗？

on在两种情况下都恢复，或者在HOME的情况下恢复另一项功能？