I need to execute a method that is in another class. I think the two are non-activity classes.
The following class has a method called connect() . When this method is executed, at the end of it I want to call another method that is in another class. The following is the class that has the connect() method. However, since I click on Connect (menu button), I need the program to also execute the publish() method that belongs to another class.
class ActionListener implements IMqttActionListener {
enum Action {
CONNECT,
DISCONNECT,
SUBSCRIBE,
PUBLISH
}
private Action action;
private String[] additionalArgs;
private String clientHandle;
private Context context;
public ActionListener(Context context, Action action,
String clientHandle, String... additionalArgs) {
this.context = context;
this.action = action;
this.clientHandle = clientHandle;
this.additionalArgs = additionalArgs;
}
@Override
public void onSuccess(IMqttToken asyncActionToken) {
switch (action) {
case CONNECT :
connect();
break;
case DISCONNECT :
disconnect();
}
}
private void disconnect() {
Connection c = Connections.getInstance(context).getConnection(clientHandle);
c.changeConnectionStatus(ConnectionStatus.DISCONNECTED);
String actionTaken = context.getString(R.string.toast_disconnected);
c.addAction(actionTaken);
}
//Daqui quero executar outro método em outra classe
private void connect() {
Connection c = Connections.getInstance(context).getConnection(clientHandle);
c.changeConnectionStatus(Connection.ConnectionStatus.CONNECTED);
c.addAction("Client Connected");
}
@Override
public void onFailure(IMqttToken token, Throwable exception) {
switch (action) {
case CONNECT :
connect(exception);
break;
case DISCONNECT :
disconnect(exception);
break;
}
}
private void disconnect(Throwable exception) {
Connection c = Connections.getInstance(context).getConnection(clientHandle);
c.changeConnectionStatus(ConnectionStatus.DISCONNECTED);
c.addAction("Disconnect Failed - an error occured");
}
private void connect(Throwable exception) {
Connection c = Connections.getInstance(context).getConnection(clientHandle);
c.changeConnectionStatus(Connection.ConnectionStatus.ERROR);
c.addAction("Client failed to connect");
Listener var = new Listener();
var.publish();
}
}
The new Listener(); object suggests the two constructors of class Listener . They are onnectionDetails connectionDetails, String clientHandle and ClientConnections clientConnections . If you leave the constructor empty, it returns nullpointerexception .
Listener.java:245 points to String topic = ((EditText) connectionDetails.findViewById...
(ActionListener.java:163) to var.publish();
(ActionListener.java:92) to case CONNECT: connect();
The second class is next. The method I want to use is PUBLISH()
public class Listener implements OnMenuItemClickListener{
private String clientHandle = null;
private ConnectionDetails connectionDetails = null;
private ClientConnections clientConnections = null;
private Context context = null;
static boolean logging = false;
public Listener(ConnectionDetails connectionDetails, String clientHandle)
{
this.connectionDetails = connectionDetails;
this.clientHandle = clientHandle;
context = connectionDetails;
}
public Listener(ClientConnections clientConnections) {
this.clientConnections = clientConnections;
context = clientConnections;
}
@Override
public boolean onMenuItemClick(MenuItem item) {
int id = item.getItemId();
switch (id)
{
case R.id.publish :
publish();
break;
case R.id.subscribe :
subscribe();
break;
}
return false;
}
private void subscribe()
{
String topic = ((EditText) connectionDetails.findViewById(R.id.topic)).getText().toString();
((EditText) connectionDetails.findViewById(R.id.topic)).getText().clear();
RadioGroup radio = (RadioGroup) connectionDetails.findViewById(R.id.qosSubRadio);
int checked = radio.getCheckedRadioButtonId();
int qos = ActivityConstants.defaultQos;
switch (checked) {
case R.id.qos0 :
qos = 0;
break;
case R.id.qos1 :
qos = 1;
break;
case R.id.qos2 :
qos = 2;
break;
}
try {
String[] topics = new String[1];
topics[0] = topic;
Connections.getInstance(context).getConnection(clientHandle).getClient()
.subscribe(topic, qos, null, new ActionListener(context, Action.SUBSCRIBE, clientHandle, topics));
}
catch (MqttSecurityException e) {
Log.e(this.getClass().getCanonicalName(), "Failed to subscribe to" + topic + " the client with the handle " + clientHandle, e);
}
catch (MqttException e) {
Log.e(this.getClass().getCanonicalName(), "Failed to subscribe to" + topic + " the client with the handle " + clientHandle, e);
}
}
//Método a ser chamado
private void publish()
{
String topic = ((EditText) connectionDetails.findViewById(R.id.lastWillTopic))
.getText().toString();
String message = ((EditText) connectionDetails.findViewById(R.id.lastWill)).getText()
.toString();
RadioGroup radio = (RadioGroup) connectionDetails.findViewById(R.id.qosRadio);
int checked = radio.getCheckedRadioButtonId();
int qos = ActivityConstants.defaultQos;
switch (checked) {
case R.id.qos0 :
qos = 0;
break;
case R.id.qos1 :
qos = 1;
break;
case R.id.qos2 :
qos = 2;
break;
}
boolean retained = ((CheckBox) connectionDetails.findViewById(R.id.retained))
.isChecked();
String[] args = new String[2];
args[0] = message;
args[1] = topic+";qos:"+qos+";retained:"+retained;
try {
Connections.getInstance(context).getConnection(clientHandle).getClient()
.publish(topic, message.getBytes(), qos, retained, null, new ActionListener(context, Action.PUBLISH, clientHandle, args));
}
catch (MqttSecurityException e) {
Log.e(this.getClass().getCanonicalName(), "Failed to publish a messged from the client with the handle " + clientHandle, e);
}
catch (MqttException e) {
Log.e(this.getClass().getCanonicalName(), "Failed to publish a messged from the client with the handle " + clientHandle, e);
}
}
}
Logcat:
--------- beginning of /dev/log/system
09-28 11:32:15.745 25770-25770/org.eclipse.paho.android.service.sample E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: org.eclipse.paho.android.service.sample, PID: 25770
java.lang.NullPointerException
at org.eclipse.paho.android.service.sample.Listener.publish(Listener.java:245)
at org.eclipse.paho.android.service.sample.ActionListener.connect(ActionListener.java:163)
at org.eclipse.paho.android.service.sample.ActionListener.onSuccess(ActionListener.java:92)
at org.eclipse.paho.android.service.MqttTokenAndroid.notifyComplete(MqttTokenAndroid.java:124)
at org.eclipse.paho.android.service.MqttAndroidClient.simpleAction(MqttAndroidClient.java:1370)
at org.eclipse.paho.android.service.MqttAndroidClient.connectAction(MqttAndroidClient.java:1325)
at org.eclipse.paho.android.service.MqttAndroidClient.onReceive(MqttAndroidClient.java:1265)
at android.support.v4.content.LocalBroadcastManager.executePendingBroadcasts(LocalBroadcastManager.java:297)
at android.support.v4.content.LocalBroadcastManager.access$000(LocalBroadcastManager.java:46)
at android.support.v4.content.LocalBroadcastManager$1.handleMessage(LocalBroadcastManager.java:116)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)