View目录下的类是GcsSloop开发的辅助工具类

RockerView是GcsSloop使用自己的工具类开发的一个摇杆控件

RockerSocketView是我写的继承自RockerView的摇杆控件

MainActivity为控件测试

四、编写过程

AS创建一个新项目

将

\Rocker-master\library\src\main\java\com\gcssloop\wid目录下的RockerView.java、

\ViewSupport-master\ViewSupport-master\Library\src\main\java\com\gcssloop下的view文件夹

复制到app\src\main\java\cn\luosh\rockertest目录下

导入后会有一些路径错误，根据自身情况修改

package cn.luosh.rockertest;
import android.content.Context;
import android.os.AsyncTask;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.Toast;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.Socket;
/**
* Created by luo76 on 2017/5/6.
*/
public class RockerSocketView extends RockerView{
//树莓派ip地址
private String carIp;
//端口
private int carPort;
//是否连接标志
private boolean isConnect = false;
private Context context;
Socket socket = null;
BufferedReader reader = null;
BufferedWriter writer = null;
private int rockerEvent = 0;
private int oldrockerEvent = -1;
//定义摇杆事件状态
public static final int Movestop = 0;
public static final int Moveforward = 1;
public static final int Movebackward = 2;
public static final int Turnleft = 3;
public static final int Turnright = 4;
//重新定义了构造方法，目的是为了得到使用该控件的Activity的context
public RockerSocketView(Context context) {
this(context, null);
}
public RockerSocketView(Context context, AttributeSet attrs) {
super(context, attrs, 0);
this.context = context;
}
//初始化函数，由使用该控件的Activity调用
public void init(String carIp,int carPort){
this.carIp = carIp;
this.carPort = carPort;
connectAsyncTask();
//添加摇杆事件监听
this.setListener(new RockerView.RockerListener() {
@Override
public void callback(int eventType, int currentAngle, float currentDistance) {
switch (eventType) {
case RockerView.EVENT_ACTION:
// 触摸事件回调
Log.e("EVENT_ACTION-------->", "angle="+currentAngle+" - distance"+currentDistance);
rockerEvent = judgeEvent(currentAngle);
send();
break;
case RockerView.EVENT_CLOCK:
// 定时回调
Log.e("EVENT_CLOCK", "angle="+currentAngle+" - distance"+currentDistance);
rockerEvent = judgeEvent(currentAngle);
send();
break;
}
}
});
}
//根据角度判断摇杆方向
public int judgeEvent(int currentAngle){
if (currentAngle == -1){
return Movestop;
}else if (currentAngle > 45 && currentAngle <= 135){
return Moveforward;
}else if (currentAngle > 135 && currentAngle <= 225){
return Turnleft;
}else if (currentAngle > 225 && currentAngle <= 315){
return Movebackward;
}else{
return Turnright;
}
}
public void Destroy(){
isConnect = false;
}
//使用异步任务建立socket连接
public void connectAsyncTask(){
AsyncTaskconnect =new AsyncTask() {
@Override
protected Void doInBackground(Void... params) {
try {
socket = new Socket(carIp,carPort);
writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
publishProgress("连接成功\n");
isConnect = true;
}catch (UnsupportedEncodingException e) {
Toast.makeText(context,"无法建立连接",Toast.LENGTH_SHORT).show();
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
Toast.makeText(context,"无法建立连接",Toast.LENGTH_SHORT).show();
}
String Line;
try {
while ((Line = reader.readLine()) != null){
publishProgress(Line);
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
protected void onProgressUpdate(String...values){
if(values[0].equals("连接成功\n")){
Toast.makeText(context,"连接成功",Toast.LENGTH_SHORT).show();
}
else{
System.out.println(values[0]);
}
super.onProgressUpdate(values[0]);
}
};
connect.execute();
}
//不使用线程，事件变化时再发送状态
public void send(){
//先判断是否成功建立socket连接再向树莓派发送数据，避免出现错误
if(isConnect){
if(rockerEvent != oldrockerEvent){
oldrockerEvent = rockerEvent;
try {
//将要发送的int数据转换成String再发送
writer.write(String.valueOf(rockerEvent));
writer.flush();
Log.e("EVENT_ACTION-------->", "rockerEvent=" + rockerEvent);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}

package cn.luosh.rockertest;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity {
private RockerSocketView rockersocket;
private EditText carip,carport;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
rockersocket = (RockerSocketView) findViewById(R.id.rockersocket);
carip = (EditText) findViewById(R.id.carip);
carport = (EditText) findViewById(R.id.carport);
findViewById(R.id.btn_car_connect).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
rockersocket.init(carip.getText().toString(),Integer.parseInt(carport.getText().toString()));
}
});
}
@Override
protected void onDestroy() {
super.onDestroy();
rockersocket.Destroy();
rockersocket = null;
}
}

最后，连上安卓实体机，打开树莓派服务端，运行