Providing delay between two codes in j2me - java-me

I am trying j2me code in which i am putting to thingd a alert message and setCurrentItem()
function..
display.setCurrent(alert);
display.setCurrentItem(textBox)
the problem is that before we can see the alert msg it disappear and because of display.setCurrent(textBox). what should i do to see the alert message correctly and than move to the item which is placed im display.setCurrentItem??

I don't really do any High Level GUI coding (meaning Form stuff), so I'm no expert.
But looking at the docs, I can see a setTimeout(int time) function on the Alert object.
So my guess is that you should display the TextBox first, and then display the Alert afterwards with a timeout.
alert.setTimeout(5000); // 5 seconds
display.setCurrent(textBox);
display.setCurrent(alert);
That should display the alert for 5 seconds, and then when dismissed, the textBox should appear.
Looking at the Display object, I also notice another function called setCurrent(Alert alert, Displayable nextDisplayable) though, which seems to be even better.
Using that method you should be able to just do
Display.setCurrent(alert, textBox);
The docs says the following about that method: "Requests that this Alert be made current, and that nextDisplayable be made current after the Alert is dismissed. This call returns immediately regardless of the Alert's timeout value or whether it is a modal alert. The nextDisplayable must not be an Alert, and it must not be null."
Bookmark and use this page a lot:
http://docs.oracle.com/javame/config/cldc/ref-impl/midp2.0/jsr118/

Related

How to pass value to confirmation popup from custom screen

I need to fire Complete Order action of Production Order Maintenance screen from my custom screen, the issue is, when action is fired am getting an error saying, "Are you sure want to complete the order" this is the same confirmation message we get when we do from Production Order Maintenance screen as well, my question is, how we can avoid this popup or how i can pass value to this popup from my custom graph.
ProdMaintGraph.ProdMaintRecords.Current = ProdItem;
ProdMaintGraph.completeorder.Press();
You can try it like this!
ProdMaintGraph.ProdMaintRecords.Cache.Graph.Views["ProdMaintRecords"].Answer = WebDialogResult.Yes;
If in the popup form Message Buttoin is Yes, or one is this values which are None,OK ,Cancel,Abort,Retry ,Ignore,Yes,No

Wait until alert is present in Chrome

I have an excel macro that enters data into a web-form (usng selenium and web driver). After each submission (by clicking submit button), a popup appears and the macro clicks OK on that alert by running this code lineobj.SwitchToAlert.accept to continue the loop . Entire code is working fine. Only problem is sometimes the alert takes 5-10 seconds to appear. That time the code proceeds to click the button and gives error (as no alert pop up is present yet).
Is there any way that macro can wait until the alert is present before running obj.SwitchToAlert.accept?
There are additional parameters in the SwitchToAlert method that you have overlooked.
The one in particular is the Optional Timeout As long = -1 parameter. Set this to a value, such as 20. This means it will wait a maximum time of 20 seconds for your alert to appear, then click accept. If it appears in 5 seconds, you only wait 5 seconds (not the full 20).
obj.SwitchToAlert(20).accept
Would be the line you are wanting to use.
When you are using the default value of -1, you are telling this method to use the global default timeout, which is 5 seconds. You can change this global value by changing the obj.Timeouts.ImplicitWait property.

XPages: possible bug with enableModifiedFlag in Release 9.0.1FP3 HF241, and workaround

I have a page where I wanted to use the "enableModifiedFlag" property, to let users know that their edit was not saved if they want to leave a page before saving.
I also have a search box in that page, and when I set the field to the static value "true", the message was popping because the search box was considered part of the page, and the field was modified. This all makes sense.
Since the "enableModifiedFlag" property can be computed, I decieded to set it to true only if the document was in edit mode, as the search box is not available at that time. The behaviour I got was that the message was not appearing anymore. I then tested with returning true as the value of the property, and it didn't change anything: the message was just gone. I then used the static values and set it to true, and the message was then appearing.
My conclusion is that there is a bug that prevents any computed value to be considered for that property.
So I had to find a workaround to prevent the message from popping up when users used the serach box. Here is the solution I came up with.
On the client side, we have access to the XSP object. One of its method is XSP._setDirty(). you can either set it to true or false, and it will affect if the page diplays the popup message or not. So in my search button, I added this code on the onclick event, on the client side:
XSP._setDirty(false,""); //so we don't get the "do you want to leave this page" message
showStandBy(); //show standby in case search is long or slow
return true;
That way, I tell my page not to show the message and the popup is not displayed.
It's still a shame you can't use the computed value for that property, but at least we have a workaround. Hope this will be useful to somebody!!!
GOT SOMETHING WORKING I THINK
This is what I have now, that controls teh flag:
<xp:this.enableModifiedFlag><![CDATA[${javascript:context.getUrlParameter("action")=="editDocument";}]]></xp:this.enableModifiedFlag>
I would rather use the document1.isEditable() function, but I wasn't successful with it so far, neither computed dynamically nor on page load.
At leaset I have something that seems to be working. Time to submit that code to the end users!

How to handle LWUIT dialogs shown on background threads

I have written an application in LWUIT targeted for a J2ME phone (Sprint DuraXT). The application is for pickup and delivery van drivers. It receives dispatches from a back-end dispatching system that describe pickups and delivers the driver must make. As the drivers, execute the pickups and deliveries, the driver enters status information that is sent back to the dispatching system.
Now, during the processing of a pickup or delivery, the driver may be presented with error dialogs (incorrect field entry), yes/no confirmation dialogs (confirming some action) and information dialogs (indicating some status the driver should be aware of).
In addition, there is a background thread listening for dispatches coming from the back-end server. In the current implementation, this background thread can also create yes/no confirmation dialogs and information dialogs. These dialogs are more like an alert as they have an associated sound, but they are simply dialogs.
As long as these two dialogs do not occur “simultaneously” every thing works as expected. You can dismiss the dialogs and the app proceeds as expected.
However, when you are on a screen and there is a dialog already showing and a second one from the background thread occurs, you sometime wind up with the wrong screen showing and it is “frozen”. E.g. the soft keys have no effect.
My hypothesis is that there is a race condition between the threads that are dismissing the dialogs. It goes like this. The EDT is blocked showing the dialog that arises as part of the form’s logic. The background thread is also blocked showing a dialog. Now when the dialog showing on the EDT is dismissed, the form is restored, but the EDT may go off and display another form (via show()). When the dialog displayed by the background thread is dismissed, the form which was showing when the dialog was initially displayed is sometimes restored. Now, the display shows a different form than the one the EDT might have shown.
It is pretty clear that this problem is caused by the dialogs resulting from the activities of the background thread. So the basic question is: “How to handle the dialogs arising from the background thread?” I have some thoughts but none yield a particularly clean implementation. I am hoping somebody has had to deal with this same problem and has a suggestion.
I have tried synchronizing the dialog construction and display so that only one dialog can get displayed at a time. This certainly improves the UI, but does not fully resolve the problem. The race begins when the first dialog is dismissed. Here are some other ideas,
If a dialog is shown by a thread other than the EDT, call show on the form at the top of the display stack when the dialog is dismissed. This is a bit of a hack, but may be a workaround.
Run dialogs to be shown by the background thread on the EDT. There are several ways to do this, but the question is will it resolve the problem? Will using an EventDispatcher help? I have experimented using an EventDispatcher to fire an ActionEvent containing a subclass of a Dialog as a source. The subclass contains a show() method which invokes the correct form of the Dialog show method. The class holding the EventDispatcher (global to the application) listens for these events. When the event arrives, the show method is invoked. For information dialogs that simply continue execution from wherever they are dismissed, this should work. For yes/no dialogs, you may have to create something like yes/no callbacks to handle the bifurcation in the logic. And what is not obvious is if this will actually serialize the processing of the dialogs on the EDT thread. This seems complicated.
Any ideas?
I actually hit upon the solution after a bit of experimentation. Because the Dialogs are part of a more compilcated action involving yes/no Dialogs and database queries, I found I had to wrap the whole action in a class which implements the Runnable interface. Then I run the action via Display.getInstance().callSeriallyAndWait(runnable).
So others may benefit from this discussion, here is a example of one of these classes with the action embedded in the run method.
private class CancelOrder implements Runnable {
private KWMap order;
public CancelOrder(KWMap order) {
this.order = order;
}
public void run() {
String orderNum = getString(order, OrderTable.ORDER_NUM);
if (legStatusTable.isOrderStarted(orderNum)
&& !orderTable.isOrderComplete(order)) {
String msg = "You received a cancellation message for Order "
+ orderNum
+ " which has been started but is not finished."
+ "\nDo you want to keep it?";
if (app.yesNoDialog(msg, "Yes", "no")) {
sendCancelResponse(order, "Yes", "");
} else {
deleteOrder(orderNum);
sendCancelResponse(order, "No", "");
}
} else {
// order has neither been started nor completed.
deleteOrder(orderNum);
sendCancelResponse(order, "Yes", "");
app.alertDialog("Dispatcher cancelled Order " + orderNum);
}
}
}
The key thing here is that the action contains logic depending on how a user responds to a yes/no Dialog and there are operations on an underlying database and messaging subsystem as well. Except for the Dialogs, nothing in this action blocks the EDT for more than a few 100s of milliseconds, so the application runs very smoothly. The app coorectly handles dislogs stacking on top of each other which was a problem with the simple apporach of letting these actions run on the background (non EDT) thread.

minimize and getting back the display

I want to minimize my app and after the timer end get it back.
I use code below.
To minimize application use following line of code:
Display.getDisplay (MIDLET_CLASS_NAME).setCurrent (null);
To get the screen back use the following:
Display.getDisplay (MIDLET_CLASS_NAME).setCurrent (myCanvas);
But when phone display is dismissed and going to clock mode my midlet display isn't shown until press any button.
any idea?
From your question it sounds that you expect setCurrent to somehow "force" device to immediately display your screen or maybe return only after screen gets visible.
This is not so, as clearly explained in the API documentation for Display.setCurrent:
Requests that a different Displayable object be made visible on the display. The change will typically not take effect immediately. It may be delayed so that it occurs between event delivery method calls, although it is not guaranteed to occur before the next event delivery method is called. The setCurrent method returns immediately, without waiting for the change to take place...
...if the application is in the background, passing a non-null reference to setCurrent may be interpreted by the application management software as a request that the application is requesting to be brought to the foreground... These are only requests, and there is no requirement that the application management software comply with these requests in a timely fashion if at all...
Consider redesigning your MIDlet to adjust to specified behavior.
If myCanvas is an instance of Canvas, one can use showNotify() events.
For a generic Displayable screen isShown() method checks if the it is actually visible on the display.
Sometimes it could even make sense to let user explicitly confirm return from background, like
display.setCurrent(new Alert("back to foreground", "dismiss to continue...",
null, AlertType.INFO), myCanvas);

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