Develop Reference

Notification when firebase is updated?

I am making a chat application where I want the a user to get a notification when the other user sends a message. I've heard you can do it with a js script and followed the google guidelines but I'm confused where am I actually writing the script? Do I have to do the free trial for the google firebase environment?

You can do like this:-
DatabaseReference ref = FirebaseDatabase.getInstance().getReference(reference)
FirebaseArray snapshots = new FirebaseArray(ref);
snapshots.setOnChangedListener(new FirebaseArray.OnChangedListener() {
#Override
public void onChanged(EventType type, int index, int oldIndex) {
switch (type) {
case Added:
break;
case Changed:
break;
case Removed:
break;
case Moved:
break;
}
}
});

android how to change from if-else to switch case

I have an application about pmt function. However there are so many conditions that need to be handled. Somehow the app will not work with having more than 12 if-else. I want to use switch case, but i still not really understand how to use switch case(been 1 and half month since my 1st try using eclipse).Any example will be highly appreciated.
here is my example code:
if(String1.toString().equals("condition1")){
//do something
if(String2.toString().equals("condition1.1")&& String3.toString().equals("condition1.2")){
//do something else
}
.
.
.
.
.
if(String2.toString().equals("condition1.##")&& String3.toString().equals("condition1.##")){
//do something else
}
}
else if(String1.toString().equals("condition2")){
//do something
if(String2.toString().equals("condition2.1")&& String3.toString().equals("condition2.2")){
//do something else
}
.
.
.
.
.
if(String2.toString().equals("condition2.##")&& String3.toString().equals("condition2.##")){
//do something else
}
}
if(String1.toString().equals("condition3")){
//do something
if(String2.toString().equals("condition3.1")&& String3.toString().equals("condition3.2")){
//do something else
}
.
.
.
.
.
if(String2.toString().equals("condition3.##")&& String3.toString().equals("condition3.##")){
//do something else
}
}
and still keep going....to handle all possibilities .I am wondering, How to do this in switch case . Or a better implementation if we have 3 times 3 conditions. For example a,b,c(suppose these three conditions can only be used once) and d,e,f and g,h,i then condition 1 is a,d,g ; condition 2 is a,d,h condition 3 is a,d,i ; condition 4 a,e,g........on so on
Note:Suppose that the API version is 8-11 (old android)
thanks

The answer is dependent on your target version of android. From KitKat and upwards (API Level 19+), Java 7's switch (String) is available. I'd also strongly suggest trying to group the subcases (condition n.x) into different methods. It just gets very unwieldly quickly, otherwise:
switch (String1.toString) {
case "condition1":
handleCase1(String2, String3);
break;
case "condition2":
handleCase2(String2, String3);
break;
}
If that still results in too complex code, you can try a lookup table together with a command pattern:
class ConditionKey {
final String String1;
final String String2;
final String String3;
public int hashCode(); // hash strings
public boolean equals(); // compare strings
}
interface ConditionCommand {
// use whatever arguments the operation needs, you can also
// add fields and initialize in the constructor
void perform(final ConditionKey key, /* [...] */);
}
Map<ConditionKey, ConditionCommand> actionMap = new HashMap<>();
actionMap.put(
new ConditionKey("condition1", "condition1.1", "condition1.2"),
new ConditionCommand() {
void perform(final ConditionKey key) {
// perform actions that need to be done
}
}
);
And then instead of the if-else or switch-case:
[...]
ConditionKey key = new ConditionKey(string1, string2, string3);
// get the action from the map
ConditionCommand command = actionMap.get(key);
// perform the command
command.perform(key);

since java 1.7 switch on string is supported.
you could annidate two switch:
switch(String1) {
case "condition1": {
switch(String2) {
case "condition1.1":
break;
// ... other cases
default:
break;
}
}
break;
// ... other cases
default break;
}

Check Directory for new files in android

I need to read all files in a directory every say 5 minutes and check if any new files have been created.
What would be the best way to do this?
I thought of using a DB to store all file names and then compare one by one but it seems like it would take too long.
I also thought of writing the file names to a text file and the looking if the file name is on the list or not.
Is there a better way?

Why don't you try with FileObservers
private final class DirectoryObserver extends FileObserver {
private DirectoryObserver(String path, int mask) {
super(path, mask);
}
#Override
public void onEvent(int event, String pathString) {
event &= FileObserver.ALL_EVENTS;
switch (event) {
case FileObserver.DELETE_SELF:
//do stuff
break;
case FileObserver.CREATE:
case FileObserver.DELETE:
//do stuff
break;
}
}
}
Ref:FileObserver CREATE or DELETE received only for files

How to detect a newly created file in android?

Is there any way to detect when a file is created or modified or downloaded in the android phone? I checked the available intents, but none of them are related to files. I am working on the broadcast receiver and couldnt figure out a way to detect a new file creation. Can someone please help?

use FileObserver...
public class MyFileObserver extends FileObserver {
public MyFileObserver(String path) {
super(path);
}
#Override
public void onEvent(int event, String path) {
switch (event) {
case DELETE:
// file deleted
break;
case ACCESS:
// file accessed;
break;
case MODIFY:
// file modified;
break;
case OPEN:
// file opened
break;
// see documentation for available events
default:
break;
}
}
}
sample usage:
MyFileObserver fileObserver = new MyFileObserver(Environment.getExternalStorageDirectory().getPath());
fileObserver.startWatching();

Android: Set Chat State Notifications in Beem App

I am currently using Beem's source code to do developments. I would like to implement the chat state notifications. I have look through the codes and found that there is a setState() method, but I believe it has not been implemented and I have no clues about how to do it. If I use Adium to type a message to the Beem user, the Beem user is able to see that the Adium user is composing a message. But if both users are using Beem, then it does not display if the user is composing a message. Therefore, I would like to try to implement the chat state notification. How do I go about doing it? Is there any guides out there? Can someone help me? Thanks!

Add this code to setState method in ChatAdapter.java file.
org.jivesoftware.smack.packet.Message message = new org.jivesoftware.smack.packet.Message();
ChatStateExtension extension = null;
switch (state) {
case "composing":
extension = new ChatStateExtension(ChatState.composing);
break;
case "active":
extension = new ChatStateExtension(ChatState.active);
break;
case "inactive":
extension = new ChatStateExtension(ChatState.inactive);
break;
case "gone":
extension = new ChatStateExtension(ChatState.gone);
break;
case "paused":
extension = new ChatStateExtension(ChatState.paused);
break;
}
message.addExtension(extension);
try {
mAdaptee.sendMessage(message);
} catch (XMPPException e) {
e.printStackTrace();
}