Develop Reference

How to get PaymentMethodNonce and deviceData on Braintree Android PayPal Vault Payment

Am trying to implement Braintree Vault PayPal payment, the problem am facing here is getting the paymentMethodNonce my event listener createdListener to capture nonce doesn't get called using vault, but everything works fine using checkout. I can't charge customer without a paymentMethodNonce, please can anyone assist me.
mBraintreeFragment = BraintreeFragment.newInstance(this,"TOKEN_FROM_SERVER");
PayPalRequest request = new PayPalRequest().localeCode("US").billingAgreementDescription("Your agreement description");
PayPal.requestBillingAgreement(mBraintreeFragment, request);
mBraintreeFragment.addListener(createdListener);
mBraintreeFragment.addListener(cancelListener);
mBraintreeFragment.addListener(errorListener);
DataCollector.collectDeviceData(mBraintreeFragment, new BraintreeResponseListener<String>() {
#Override
public void onResponse(String deviceData) {
Log.e("PayPal", deviceData);
try {
JSONObject json = new JSONObject(deviceData);
deviceDataInfo = json.getString("correlation_id");
Log.e("PayPal", deviceDataInfo);
} catch (JSONException e) {
e.printStackTrace();
}
}
});
My Listeners
PaymentMethodNonceCreatedListener createdListener = new PaymentMethodNonceCreatedListener() {
#Override
public void onPaymentMethodNonceCreated(PaymentMethodNonce paymentMethodNonce) {
String nonce = paymentMethodNonce.getNonce();
Log.d("PayPal", "nonce id " + nonce);
}
};
BraintreeCancelListener cancelListener = new BraintreeCancelListener() {
#Override
public void onCancel(int requestCode) {
Log.d("CreditCard", "Braintree Error Code " + requestCode);
}
};
BraintreeErrorListener errorListener = new BraintreeErrorListener() {
#Override
public void onError(Exception error) {
if (error instanceof ErrorWithResponse) {
ErrorWithResponse errorWithResponse = (ErrorWithResponse) error;
BraintreeError cardErrors = errorWithResponse.errorFor("creditCard");
if (cardErrors != null) {
List<BraintreeError> errors = cardErrors.getFieldErrors();
String err = Objects.requireNonNull(errors.get(0).getMessage());
Log.d("CreditCard", errors.toString());
}
}
}
};

Instead of adding manually your listeners to that request, it's better to just implement the interface from braintree.
For example, if you want to use the onPaymentMethodNonceCreated() just add "implements PaymentMethodNonceCreatedListener" after your class name.
public class "YourClass" implements PaymentMethodNonceCreatedListener {
//...
}
And then override the method that now the Android Studio is warning you:
#Override
public void onPaymentMethodNonceCreated(PaymentMethodNonce paymentMethodNonce) {
String nonce = paymentMethodNonce.getNonce();
//...
}
This way you can go for everyone of your listeners! Good luck!

Android: NullPointerException 'double java.lang.Double.doubleValue()'

I'm new to android programming and I'm having a problem with my codes. Can anyone help me or point out the cause of my error because I'm not really sure why it's giving me a NullPointerException when its a text view or if that is possible.
LogCat:
java.lang.NullPointerException: Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on a null object reference
at com.example.app.rosbridge.MainActivity$2$1.run(MainActivity.java:133)
Here is the code for that line:
current.setText(String.format("%.4f%s", batteryStateData.msg.current * Math.pow(10, 6), "A"));
But when i run my app my voltage is setting null and here is the code for the voltage:
voltage.setText(String.format("%.4f%s", batteryStateData.msg.voltage, "v"));
Here is the full code:
public class MainActivity extends Activity {
private TextView voltage, current, percentage, status;
private SubscribedData<BatteryState> batteryStateData;
private RosbridgeListener rosbridge;
private boolean subscribed = false;
private boolean advertised = false;
/** Indicates that Lint should ignore the specified warnings for the annotated element. */
#SuppressLint("ClickableViewAccessibility")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_activity);
Button settings_btn = (Button) findViewById(R.id.connect_btn);
voltage = findViewById(R.id.voltage_txt);
current = findViewById(R.id.current_txt);
percentage = findViewById(R.id.percentage_txt);
status = findViewById(R.id.status_txt);
connectButton = findViewById(R.id.connect_btn);
batteryStateData = new SubscribedData<>();
final Type batteryStateType = new TypeToken<SubscribedData<BatteryState>>() {
}.getType();
// ROSBRIDGE protocol allows access to underlying ROS messages and services as serialized JavaScript Object Notation (JSON) objects
WebSocket protocol communicates to a server for the connection from a user's web browser
//A connection to the rosbridge thru the IP address of the robot from the socket
rosbridge = new RosbridgeListener("ws://10.24.204.231:9090");
rosbridge.setOnDataReceivedListener(new RosbridgeMessageListener() {
// a running thread that when the connection is made the data of the topic will serialize and deserialized java objects to (and from) JSON. #param msg
#Override
public void onDataReceived(final String msg) {
try {
runOnUiThread(new Runnable() {
#Override
public void run() {
batteryStateData = new Gson().fromJson(msg, batteryStateType);
voltage.setText(String.format("%.4f%s", batteryStateData.msg.voltage, "v"));
current.setText(String.format("%.4f%s", batteryStateData.msg.current * Math.pow(10, 6), "A"));
percentage.setText(String.format("%.2f%s", batteryStateData.msg.percentage, "%"));
status.setText(String.format("%s", PowerSupplyStatus.values()[batteryStateData.msg.powerSupplyStatus]));
}
});
Log.d("B9T", String.format("Received data: %s", msg));
}
catch (Exception e)
{
e.printStackTrace();
}
}
});
connectButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (!subscribed) {
rosbridge.Subscribe("/battery", "sensor_msgs/BatteryState");
subscribed = true;
connectButton.setText("Disconnect");
} else {
rosbridge.UnSubscribe("/battery");
subscribed = false;
connectButton.setText("Connect");
}
}
});

Everytime when you are setting the text to textview, you must need to check if it is not null.

You can check null before you set text on textview like the following.
#Override
public void run() {
batteryStateData = new Gson().fromJson(msg, batteryStateType);
// check null before set text or calculate something
if(batteryStateData.msg.current != null){
current.setText(String.format("%.4f%s", batteryStateData.msg.current * Math.pow(10, 6), "A"));
}
// you can check belows like above
voltage.setText(String.format("%.4f%s", batteryStateData.msg.voltage, "v"));
percentage.setText(String.format("%.2f%s", batteryStateData.msg.percentage, "%"));
status.setText(String.format("%s", PowerSupplyStatus.values()[batteryStateData.msg.powerSupplyStatus]));
}

Check weather your created class with GSON is not null
and then check class fields values is not null or 0.
batteryStateData = new Gson().fromJson(msg, batteryStateType);
if (batteryStateData != null) {
if (batteryStateData.msg.voltage!=0)
voltage.setText(String.format("%.4f%s", batteryStateData.msg.voltage, "v"));
if (batteryStateData.msg.current!=0)
current.setText(String.format("%.4f%s", batteryStateData.msg.current * Math.pow(10, 6), "A"));
if (batteryStateData.msg.percentage!=0)
percentage.setText(String.format("%.2f%s", batteryStateData.msg.percentage, "%"));
if (batteryStateData.msg.values !=null)
status.setText(String.format("%s", PowerSupplyStatus.values()[batteryStateData.msg.powerSupplyStatus]));
}

How to create a modular class for barcode scanning using Firebase ML Kit

I want to create a modular class that I can use anytime I want to scan a barcode. Is this possible using Firebase ML Kit?
This is what I've got so far:
public List<FirebaseVisionBarcode> ScanBarcode(int... barcodeFormats)
{
//region Init, config and execution of the barcode scanning
final FirebaseVisionBarcodeDetectorOptions.Builder BUILDER =
new FirebaseVisionBarcodeDetectorOptions.Builder();
//Set barcode formats based on arguments
for (int formats : barcodeFormats)
{
BUILDER.setBarcodeFormats(formats);
}
final FirebaseVisionBarcodeDetectorOptions OPTIONS = BUILDER.build();
final FirebaseVisionImage IMAGE = FirebaseVisionImage.fromBitmap(bitmap);
final FirebaseVisionBarcodeDetector DETECTOR = FirebaseVision.getInstance()
.getVisionBarcodeDetector(OPTIONS);
DETECTOR.detectInImage(IMAGE)
.addOnSuccessListener(new OnSuccessListener<List<FirebaseVisionBarcode>>()
{
#Override
public void onSuccess(List<FirebaseVisionBarcode> _barcodes)
{
barcodes = _barcodes;
}
})
.addOnFailureListener(new OnFailureListener()
{
#Override
public void onFailure(#NonNull Exception e)
{
barcodes = new ArrayList<>();
}
});
//endregion
return barcodes;
Mostly taken from https://firebase.google.com/docs/ml-kit/
The problem here is that the listener, for the DETECTOR, is some kind of async call. Which means that it will return before onSuccess is called.
The barcode scanning part works, but I'm having a hard time wrapping it in a class of it's own.
Thanks.

I figured it out. Not sure if it's the best approach class structure wise, but it works quite nice.
public Task<List<FirebaseVisionBarcode>> ScanBarcode(int... barcodeFormats)
{
//region Init, config and execution of the barcode scanning. Mostly taken from https://firebase.google.com/docs/ml-kit/
final FirebaseVisionBarcodeDetectorOptions.Builder BUILDER =
new FirebaseVisionBarcodeDetectorOptions.Builder();
//Set barcode formats based on arguments
for (int formats : barcodeFormats)
{
BUILDER.setBarcodeFormats(formats);
}
final FirebaseVisionBarcodeDetectorOptions OPTIONS = BUILDER.build();
final FirebaseVisionImage IMAGE = FirebaseVisionImage.fromBitmap(bitmap);
final FirebaseVisionBarcodeDetector DETECTOR = FirebaseVision.getInstance()
.getVisionBarcodeDetector(OPTIONS);
final Task<List<FirebaseVisionBarcode>> DETECT_IMG_TASK = DETECTOR.detectInImage(IMAGE)
.addOnSuccessListener(new OnSuccessListener<List<FirebaseVisionBarcode>>()
{
#Override
public void onSuccess(List<FirebaseVisionBarcode> _barcodes)
{
barcodes = _barcodes;
}
})
.addOnFailureListener(new OnFailureListener()
{
#Override
public void onFailure(#NonNull Exception e)
{
barcodes = new ArrayList<>();
}
});
return DETECT_IMG_TASK;
//endregion
}
public List<FirebaseVisionBarcode> GetBarcodes()
{
return barcodes;
}
detectInImage returns a Task. What I did was return this task. Once this task completes, you can call GetBarcodes to obtain the parsed data. I hate to force calling additional methods to get the final results, but it was the only way I could get it to work.

javafx adding multiple strings into TextArea in one method -> Everything is written once at the end

I have a javafx program which I want to use to analyze a website. For the start I just want to print the sourcecode of a site into a TextArea, but before that, I write "loading website sourcecode..."
My target is to write "loading website sourcecode..." first, and then after some seconds when the parsing of the site is finished, add that sourcecode.
At the Moment when I press the button, nothing happens and after 3-5 seconds the "loading website sourcecode..." message and the sourcecode is displayed at once.
So I actually want to show strings one after another. I already googled for 2 hours and tried things with threads, invokelater, platform.runLater() and so on but nothing worked, the code is simple.
ModelView.java - Controller Class
package root;
import javafx.application.Platform;
...
public class ModelView {
#FXML public TextField UrlInput;
// This gets called when the button is pressed
public void checkUrl() throws InterruptedException
{
String url = UrlInput.getText();
LogWriter lw = new LogWriter();
lw.printMsg("loading website sourcecode...");
lw.printMsg(HTMLParser.directUrlToCode(url));
}
}
LogWriter.java
package root;
import javafx.beans.value.ObservableValue;
...
public class LogWriter extends Thread{
#FXML TextArea Log;
public LogWriter()
{
Log = (TextArea) Main.scene.lookup("#Log");
}
void printMsg(String s)
{
Log.setText(this.Log.getText()+"\n"+s);
}
}
EDIT:
There is not much to say about the HTMLParser methods, but I add that it extends Thread.
I tried changing ModelView.java to that:
ModelView.java - version 2
package root;
import javafx.application.Platform;
...
public class ModelView<V> {
#FXML public TextField UrlInput;
// This gets called when the button is pressed
public void checkUrl() throws InterruptedException
{
String url = UrlInput.getText();
LogWriter lw0 = new LogWriter();
lw0.start();
lw0.printMsg("loading website sourcecode...");
HTMLParser hp = new HTMLParser();
hp.start();
LogWriter lw1 = new LogWriter();
lw1.start();
lw1.printMsg(hp.directUrlToCode(url));
}
}
Still the same effect.
EDIT2:
This is another version I tried, in this case, "loading website sourcecode..." is not even displaying, I am going on with my tries...
ModelView.java checkUrl() - Version 3
public void checkUrl() throws InterruptedException
{
String url = UrlInput.getText();
Task<Void> task = new Task<Void>(){
#Override protected Void call() throws Exception {
if(isCancelled()) {
updateMessage("Cancelled");
LogWriter lw = new LogWriter();
lw.printMsg("loading website sourcecode...");
}
return null;
}
};
Thread t = new Thread(task);
t.start();
HTMLParser hp = new HTMLParser();
LogWriter lw1 = new LogWriter();
lw1.printMsg(hp.directUrlToCode(url));
}

First of all, manipulating an observable variable from outside of the JavaFX application thread is a bad idea. You won't be able to bind other variables to it (you'll get IllegalStateExceptions)
Second, I'd implement LogWriter like this:
// ...
public class LogWriter {
private final TextArea txtLog;
public LogWriter(TextArea txtLog) {
this.txtLog = txtLog;
}
void printMsg(final String s) {
if (!Platform.isFxApplicationThread()) {
Platform.runLater(new Runnable() {
#Override
public void run() {
printMsg(s);
}
});
} else {
txtLog.setText(txtLog.getText() + "\n" + s);
}
}
}
and use it this way:
//...
#FXML
private TextArea txtLog;
// ...
public void checkUrl() {
final String url = UrlInput.getText();
final LogWriter lw = new LogWriter(txtLog);
Task<String> task = new Task<String>() {
#Override
protected String call() {
lw.printMsg("loading website sourcecode...");
return HTMLParser.directUrlToCode(url);
}
#Override
protected void succeeded() {
super.succeeded();
lw.printMsg(getValue());
}
#Override
protected void failed() {
super.failed();
if (getException() != null) {
getException().printStackTrace();
}
lw.printMsg("failed!");
}
};
new Thread(task).start();
}
Note that HTMLParser does not need to extend Thread.

Hooking a GWT event onto an element in an external iframe

I am writing a GWT app that involves interacting with an external document in an iframe. As a proof of concept, I am trying to attach a click handler to a button.
The following works in javascript
var iframe = document.getElementById("rawJSIFrame");
var doc = iframe.contentDocument;
var body = doc.body;
var button = doc.getElementsByTagName("input").namedItem("submit");
button.onclick = function() {
alert("Clicked!");
};
Trying to do the equivalent in GWT, I did the following:
public void addClickHandlerToSubmitButton(String buttonElementName, ClickHandler clickHandler) {
IFrameElement iframe = IFrameElement.as(frame.getElement());
Document frameDocument = getIFrameDocument(iframe);
if (frameDocument != null) {
Element buttonElement = finder(frameDocument).tag("input").name(buttonElementName).findOne();
ElementWrapper wrapper = new ElementWrapper(buttonElement);
HandlerRegistration handlerRegistration = wrapper.addClickHandler(clickHandler);
}
}
private native Document getIFrameDocument(IFrameElement iframe)/*-{
return iframe.contentDocument;
}-*/;
The following is the ElementWrapper class:
public class ElementWrapper extends Widget implements HasClickHandlers {
public ElementWrapper(Element theElement) {
setElement(theElement);
}
public HandlerRegistration addClickHandler(ClickHandler handler) {
return addDomHandler(handler, ClickEvent.getType());
}
}
The code to find the button works fine but the actual click event handler is not getting invoked. Has anybody had a similar issue before, and how did you resolve it?
Thanks in advance,
Tin

Hilbrand is right about the problem being that the GWT method onAttach() was not called.
I implemented your original solution, adding the following method to ElementWrapper:
public void onAttach() {
super.onAttach();
}
And called added wrapper.onAttach() after the ElementWrapper is created. Works like a charm!

I expect the problem is that the GWT method onAttach() is not called when you use the wrapping as in your first example. You can try to use the static wrap method on the Button widget. Although to use this the input must be of type button. Or have a look at the implementation of the wrap method. Here is the modified code when using the wrap method:
Element buttonElement = finder(frameDocument).tag("input").name(buttonElementName).findOne();
Button button = Button.wrap(buttonElement);
HandlerRegistration handlerRegistration = button.addClickHandler(clickHandler);

After researching this further, I found that the iframe is irrelevant. The same behaviour doesn't work on a normal button on the host page.
I basically fixed it by using JSNI to replicate part of GWT's event handling mechanism. The following works:
Element buttonElement = DOM.getElementById("externalButton");
new CustomElementWrapper(buttonElement).addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
Window.alert("GWT hooked into button");
}
});
Where CustomElementWrapper is:
public class CustomElementWrapper extends Widget implements HasClickHandlers {
private ClickEventManager clickEventManager;
public CustomElementWrapper(Element theElement) {
setElement(theElement);
clickEventManager = new ClickEventManager(theElement);
}
public HandlerRegistration addClickHandler(ClickHandler handler) {
//The 'right' way of doing this would be the code below. However, this doesn't work
// A bug in GWT?
//
// return addDomHandler(handler, ClickEvent.getType());
return clickEventManager.registerClickHandler(handler);
}
void invokeClickHandler() {
clickEventManager.invokeClickHandler();
}
public boolean isClickHandlerRegistered() {
return clickEventManager.isClickHandlerRegistered();
}
}
Finally, the ClickEventManager, where the actual work happens is:
public class ClickEventManager {
private boolean clickHandlerRegistered = false;
private ClickHandler clickHandler;
private Element element;
public ClickEventManager(Element element) {
this.element = element;
}
public void invokeClickHandler() {
//This shouldn't really be null but we are bypassing GWT's native event mechanism
//so we can't create an event
clickHandler.onClick(null);
}
public boolean isClickHandlerRegistered() {
return clickHandlerRegistered;
}
HandlerRegistration registerClickHandler(ClickHandler handler) {
clickHandler = handler;
if (!clickHandlerRegistered) {
registerClickHandlerInJS(element);
clickHandlerRegistered = true;
}
return new HandlerRegistration() {
public void removeHandler() {
//For now, we don't support the removal of handlers
throw new UnsupportedOperationException();
}
};
}
private native void registerClickHandlerInJS(Element element)/*-{
element.__clickManager = this;
element.onclick
= function() {
var cm = this.__clickManager;
cm.#com.talktactics.agent2.client.widgets.ClickEventManager::invokeClickHandler()();
}
}-*/;
}
Personally, I hate this solution because I appear to be duplicating GWT's event handling and quite possibly introducing nasty javascript memory leaks. Any ideas on why my first post doesn't work (remembering that the iframe aspect is a red herring), would be appreciated.
Thanks,
Tin

You may find this helpful:
import com.google.gwt.dom.client.Element;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.HasClickHandlers;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.AbsolutePanel;
public class DirectPanel extends AbsolutePanel implements HasClickHandlers {
public DirectPanel(Element elem) {
super(elem.<com.google.gwt.user.client.Element> cast());
onAttach();
}
#Override
public HandlerRegistration addClickHandler(ClickHandler handler) {
return addDomHandler(handler, ClickEvent.getType());
}
}
You will then be able to make arbitrary containers into widget containers:
Element root = Document.get().getElementById("target");
DirectPanel p = new DirectPanel(root);
Button register = new Button("Register");
register.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// ...
}
});
p.add(register);
And bind events to arbitrary elements:
Element root = Document.get().getElementById("target");
DirectPanel p = new DirectPanel(root);
p.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// ...
}
});
Specifically in your case, try this:
IFrameElement frm = Document.get().createIFrameElement();
Document d = frm.getContentDocument();
NodeList<Element> inputs = d.getElementsByTagName("input");
InputElement target = null;
for(int i = 0; i < inputs.getLength(); ++i) {
Element e = inputs.getItem(0);
if (e.getNodeName().equals("submit")) {
target = InputElement.as(e);
break;
}
}
if (target != null) {
DirectPanel p = new DirectPanel(target);
p.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
// TODO Auto-generated method stub
}
});
}
It's always mystified me that GWT makes doing this so difficult and poorly documented.

Instead of using iframes i suggest you simply make a http request from GWT via com.google.gwt.http.client.RequestBuilder. Like so:
private void getHtml(String url) {
RequestBuilder rb = new RequestBuilder(RequestBuilder.GET, url);
rb.setCallback(new RequestCallback() {
#Override
public void onResponseReceived(Request request, Response response) {
HTMLPanel html = new HTMLPanel(response.getText());
// Now you have a widget with the requested page
// thus you may do whatever you want with it.
}
#Override
public void onError(Request request, Throwable exception) {
Log.error("error " + exception);
}
});
try {
rb.send();
} catch (RequestException e) {
Log.error("error " + e);
}
}

You could use JSNI to reuse your JavaScript piece of code. Your javascript code would call a gwt method on an object that would throw it on behalf of the button in the iframe.
As to why GWT code does not work -- I guess that is because they use some layer on top of regular browser events that probably cannot span more than 1 frame. That's just a guess though. You could file this as a feature/bug request agains GWT team. If I am right your code looks just fine.

Please see my previous answer. A slight modification to your original solution will make it work.