Hola, estoy desarrollando una interfaz para comunicarme desde un celular a una raspberry mediante wifi, hasta ahora me descargue los ejemplos de simplechat, el problema es que quiero ejecutar un comando en la consola de linux, en realidad si se ejecuta (video) pero ya luego el programa de b4j se cierra, ya he hecho por separado ejecutar aplicaciones con la consola, sin embargo aquí me genera el siguiente error al finalizar el vídeo.
Connected: true
main._appstart (java line: 70)
java.lang.RuntimeException: java.lang.NullPointerException
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:120)
at anywheresoftware.b4a.BA$3.run(BA.java:247)
at anywheresoftware.b4a.keywords.SimpleMessageLoop.runMessageLoop(SimpleMessageLoop.java:30)
at anywheresoftware.b4a.StandardBA.startMessageLoop(StandardBA.java:26)
at anywheresoftware.b4a.keywords.Common.StartMessageLoop(Common.java:153)
at b4j.example.main._appstart(main.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:78)
at b4j.example.main.main(main.java:30)
Caused by: java.lang.NullPointerException
at anywheresoftware.b4j.object.WebSocket.access$0(WebSocket.java:134)
at anywheresoftware.b4j.object.WebSocket$JQueryElement.RunMethod(WebSocket.java:195)
at anywheresoftware.b4j.object.WebSocket$JQueryElement.SetText(WebSocket.java:246)
at b4j.example.main$ResumableSub_NewMessage.resume(main.java:120)
at b4j.example.main._newmessage(main.java:76)
at b4j.example.connector._client_messagearrived(connector.java:83)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
... 12 more
Gracias (no encontre la manera de como subir los .zip de mi trabajo para informacion) les dejo mi codigo en java
//segundoo
Connected: true
main._appstart (java line: 70)
java.lang.RuntimeException: java.lang.NullPointerException
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:120)
at anywheresoftware.b4a.BA$3.run(BA.java:247)
at anywheresoftware.b4a.keywords.SimpleMessageLoop.runMessageLoop(SimpleMessageLoop.java:30)
at anywheresoftware.b4a.StandardBA.startMessageLoop(StandardBA.java:26)
at anywheresoftware.b4a.keywords.Common.StartMessageLoop(Common.java:153)
at b4j.example.main._appstart(main.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:78)
at b4j.example.main.main(main.java:30)
Caused by: java.lang.NullPointerException
at anywheresoftware.b4j.object.WebSocket.access$0(WebSocket.java:134)
at anywheresoftware.b4j.object.WebSocket$JQueryElement.RunMethod(WebSocket.java:195)
at anywheresoftware.b4j.object.WebSocket$JQueryElement.SetText(WebSocket.java:246)
at b4j.example.main$ResumableSub_NewMessage.resume(main.java:120)
at b4j.example.main._newmessage(main.java:76)
at b4j.example.connector._client_messagearrived(connector.java:83)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
... 12 more
Gracias
B4X:
'Non-UI application (console / server application)
#Region Project Attributes
#CommandLineArgs:
#MergeLibraries: True
#End Region
#If JAVA
import java.io.BufferedReader;
import java.io.InputStreamReader;
//Execute a command AND capture the output In a String
//Parameter: Command To run
//Returns: String with the command output
public static String ExecuteCommand(String command) {
StringBuffer output = new StringBuffer();
Process p;
try
{
p = Runtime.getRuntime().exec(command);
p.waitFor();
BufferedReader reader =
new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = "";
while ((line = reader.readLine())!= null)
{
output.append(line + "\n");
}
}
catch (Exception e)
{
//e.printStackTrace();
return "Error executing command " + command;
}
//System.out.println(output);
return output.toString();
}
#End If
Sub Process_Globals
'Private fx As JFX
'Public MainForm As Form
' Private btnConnect As Button
'Private btnSend As Button
' Private Label1 As Label
'Private lstUsers As ListView
' Private txtHost As TextField
' Private txtLogs As TextArea
'Private txtMessage As TextField
Type Message (Body As String, From As String)
' Private txtName As TextField
Private DirData As String
' Private palabra As String
Public joInlineJava As JavaObject = Me
Private consoleoutput As JQueryElement
End Sub
Sub AppStart (Args() As String)
DirData=File.DirData("controladorjava")
Connector.ConnectTo("192.168.1.64", "ServidorJava")
StartMessageLoop
End Sub
'Return true to allow the default exceptions handler to handle the uncaught exception.
Sub Application_Error (Error As Exception, StackTrace As String) As Boolean
Return True
End Sub
Public Sub NewMessage(msg As Message)
'txtLogs.Text = txtLogs.Text & $"${msg.From}: ${msg.Body}"$ & CRLF
'txtLogs.SetSelection(txtLogs.Text.Length, txtLogs.Text.Length)
If msg.Body = "1" Then
Dim cmd As String
cmd = "omxplayer /home/pi/Desktop/pregunta1.mp4"
Dim Res As String = joInlineJava.RunMethod("ExecuteCommand",Array(cmd))
consoleoutput.SetText(Res)
' Dim palabra As String = "a" sirve para enviar la pabra o el estrig que se desea
' Connector.SendMessage(palabra) enviar palabra
Sleep(5000)
StopMessageLoop
End If
If msg.Body = "2" Then
Dim cmd As String
cmd = "omxplayer /home/pi/Desktop/pregunta2.mp4"
Dim Res As String = joInlineJava.RunMethod("ExecuteCommand",Array(cmd))
consoleoutput.SetText(Res)
End If
If msg.Body = "3" Then
'Dim cmd As String
'cmd = "omxplayer /home/pi/Desktop/pregunta3.avi"
'Dim Res As String = joInlineJava.RunMethod("ExecuteCommand",Array(cmd))
'consoleoutput.SetText(Res)
Dim shl As Shell
Dim cmd As String = "omxplayer /home/pi/Desktop/pregunta3.avi"
shl.Initialize("shl","omxplayer /home/pi/Desktop/pregunta3.avi",Array(cmd))
shl.Run(10000)
End If
End Sub
Sub txtMessage_Action
'btnSend_Action
End Sub
Public Sub NewUsers(Users As List)
'stUsers.Items.Clear
'For Each u As String In Users
' lstUsers.Items.Add(u)
' Next
End Sub
B4X:
Sub Process_Globals
Private client As MqttClient
Private const port As Int = 51042
Private serializator As B4XSerializator
Public connected As Boolean
Private currentName As String
End Sub
Public Sub ConnectTo(Host As String, Name As String)
Disconnect
currentName = Name
client.Initialize("client", $"tcp://${Host}:${port}"$, "desktop" & Rnd(1, 10000000))
Dim mo As MqttConnectOptions
mo.Initialize("", "")
mo.SetLastWill("all/disconnect", serializator.ConvertObjectToBytes(currentName), 0, False)
client.Connect2(mo)
End Sub
Private Sub client_Connected (Success As Boolean)
Log($"Connected: ${Success}"$)
If Success Then
connected = True
client.Subscribe("all/#", 0)
client.Publish2("all/connect", serializator.ConvertObjectToBytes(currentName), 0, False)
Else
' fx.Msgbox(Main.MainForm, "Error connecting: " & LastException, "")
End If
End Sub
Private Sub client_MessageArrived (Topic As String, Payload() As Byte)
Dim receivedObject As Object = serializator.ConvertBytesToObject(Payload)
If Topic = "all/connect" Or Topic = "all/disconnect" Then
'new client has connected or disconnected
'do nothing. The server will handle it.
Else if Topic = "all/users" Then
Dim newUsers As List = receivedObject
Main.NewUsers(newUsers)
Else
Dim m As Message = receivedObject
Main.NewMessage(m)
End If
End Sub
Public Sub SendMessage(Body As String)
If connected Then
client.Publish2("all", CreateMessage(Body), 0, False)
End If
End Sub
Public Sub Disconnect
If connected Then
connected = False
client.Publish2("all/disconnect", serializator.ConvertObjectToBytes(currentName), 0, False)
client.Close
End If
End Sub
Private Sub CreateMessage(Body As String) As Byte()
Dim m As Message
m.Initialize
m.Body = Body
m.From = currentName
Return serializator.ConvertObjectToBytes(m)
End Sub
Private Sub client_Disconnected
If connected Then
End If
connected = False
End Sub
Sub Application_Error (Error As Exception, StackTrace As String) As Boolean
Return True
End Sub
Sub Service_Destroy
End Sub