Creating a Public Forum
A public forum is a common way to share information with other users. Forums are often organized around a particular subject. The following use case describes how to create public forum functionality in your app and illustrates the use of the APIs by creating a channel for the SF Giants.
Create Channel
In Magnet Message, our channel object is how messages are sent to and received by a group. To create a public channel (SFGiants):
NOTE: The channel creator is automatically subscribed to the channel.
MMXChannel.create("SFGiants","The Giants Channel",true,new MMXChannel.OnFinishedListener<MMXChannel>(){
@Override
public void onSuccess(MMXChannel mmxChannel) {
//Success
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//Failure
}
});
Discover Channels
Next, discover channels that you can subscribe to:
- To disover channels that start with
SF:
int limit = 10;
int offset = 0;
String prefix = "SF";
MMXChannel.findPublicChannelsByName("SF", limit, offset, new MMXChannel.OnFinishedListener<ListResult<MMXChannel>>() {
@Override
public void onSuccess(ListResult<MMXChannel> mmxChannelListResult) {
//Success
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//Failure
}
});
- To discover all public channels:
int limit = 10;
int offset = 0;
MMXChannel.getAllPublicChannels(limit, offset, new MMXChannel.OnFinishedListener<ListResult<MMXChannel>>() {
@Override
public void onSuccess(ListResult<MMXChannel> mmxChannelListResult) {
//Success
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//Failure
}
});
- To get a specific public channel with a known name (
SFGiants):
MMXChannel.getPublicChannel("SFGiants", new MMXChannel.OnFinishedListener<MMXChannel>() {
@Override
public void onSuccess(MMXChannel mmxChannel) {
//Success
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//Failure
}
});
Check Channel Subscription
After discovering a channel, check if the current user is subscribed to the channel:
MMXChannel sfGiantsChannel = ...;
if (sfGiantsChannel.isSubscribed()) {
Log.d("follow", "I'm following the Giants!");
}
Subscribe to Channel
To subscribe to a channel (sfGiants) so the user can send and receive messages:
MMXChannel sfGiantsChannel = ...;
// If I'm not following the Giants already, follow them now.
if (!sfGiantsChannel.isSubscribed()) {
sfGiantsChannel.subscribe(new MMXChannel.OnFinishedListener<String>() {
public void onSuccess(String s) {
...
}
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
...
}
});
}
Unsubscribe from Channel
To unsubscribe from a channel (sfSeals):
MMXChannel sfSealsChannel = ...;
// If I'm following the Seals already, unfollow them now.
if (sfSealsChannel.isSubscribed()) {
sfSealsChannel.unsubscribe(new MMXChannel.OnFinishedListener<Boolean>() {
public void onSuccess(Boolean aBoolean) {
...
}
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
...
}
});
}
View Channel Subscribers
After subscribing, you can see other subscribers to the channel (sfGiants):
MMXChannel sfGiantsChannel = ...;
int limit = 10;
int offset = 0;
sfGiantsChannel.getAllSubscribers(limit, offset, new MMXChannel.OnFinishedListener<ListResult<User>>() {
@Override
public void onSuccess(ListResult<User> userListResult) {
//Success
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//Failure
}
});
Get Published Messages on Channel
To get all the channel content from the last hour:
MMXChannel sfGiantsChannel = ...;
int limit = 10;
int offset = 0;
Date now = new Date();
Date anHourAgo = new Date(now.getTime() - (60 * 60 * 1000l));
boolean ascending = false;
sfGiantsChannel.getMessages(anHourAgo, now, limit, offset, ascending, new MMXChannel.OnFinishedListener<ListResult<MMXMessage>>(){
@Override
public void onSuccess(ListResult<MMXMessage> messages) {
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
}
});
Publish Message to Channel
To publish a message to the channel:
MMXChannel sfGiantsChannel = ...;
HashMap<String, String> content = new HashMap<String,String>();
String messageId = sfGiantsChannel.publish(content, new MMXChannel.OnFinishedListener<String>() {
public void onSuccess(String s) {
//successfully published a message to this channel
}
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
//failed publishing to this channel
}
});
Get Channel Details
After discovering a channel or channels, you can get various channel details, including the latest messages and subscribers in one API call:
List<MMXChannel> channels = ...;
MMXChannel.getChannelDetail(channels,
new ChannelDetailOptions.Builder()
.numOfMessages(10) // number of latest messages to retrieve
.numOfSubcribers(5) // number of subscribers to retrive
.build(),
new MMXChannel.OnFinishedListener<List<ChannelDetail>>() {
@Override
public void onSuccess(List<ChannelDetail> channelDetails) {
if (null != channelDetails && !channelDetails.isEmpty()) {
}
}
@Override
public void onFailure(MMXChannel.FailureCode failureCode, Throwable throwable) {
}
});
Retrieve Messages
When logged in, messages can either be retrieved using MMXChannel.getMessages() or by implementing MMX.EventListener.onMessageReceived():
MMXChannel sfGiantsChannel = ...;
MMX.EventListener eventListener = new MMX.EventListener() {
public boolean onMessageReceived(MMXMessage mmxMessage) {
if (mmxMessage.getChannel().getName().equalsIgnoreCase(sfGiantsChannel.getName())) {
//this is a message published to sfGiantsChannel
...
}
return true; //true consumes this message and prevents other listeners from getting called
}
};
MMX.registerListener(eventListener);
Next Steps
See how to create a Private Discussion Group in your app.
