How do I mask the current page behind a modal dialog box in vanilla GWT? - user-interface

I've built a log-in composite that I am displaying in my application entry-point to the user. Upon entry of the username and password, I am sending the username and password to the server via a RemoteService and will receive back an object containing the ClientSession. If the ClientSession is a valid object (recognised username and password), I wish to display the main application panel otherwise I want to display the login dialog again (with an error message).
My question is, that during the async call to the server, how to I mask the screen so that the user cannot click anything whilst the Session is obtained from the server?
I know that the login should be fast, but the Session object contains a lot of Client Side cached values for the current user that is used to generate the main panel. This may take a fraction of a second or up to 5 seconds (I can't control the speed of the underlying infrastructure unfortunately) so I want to mask the screen until a timeout is reached then allow the user to try again.
I have done this exact operation before using GWT Ext, but vanilla GWT seems to have a lot less samples unfortunately.
Thanks
Chris

The GWT class PopupPanel has an optional "glass panel" that blocks interaction with the page underneath.
final PopupPanel popup = new PopupPanel(false, true); // Create a modal dialog box that will not auto-hide
popup.add(new Label("Please wait"));
popup.setGlassEnabled(true); // Enable the glass panel
popup.center(); // Center the popup and make it visible

You might want to check out GlassPanel from the GWT Incubator project. AFAICT it's not perfect, but should be of some help nevertheless ;)

You can also use a dialog box for this purpose.
Here is the code how to use it.
public class NTMaskAlert extends DialogBox {
private String displayText;
private String message;
private static NTMaskAlert alert;
Label lable;
private NTMaskAlert(String text) {
setText(text);
setWidget(new Image(GWT.getModuleBaseURL()
+ "/images/ajax-loader_1.gif"));
setGlassEnabled(true);
setAnimationEnabled(true);
super.show();
super.center();
WorkFlowSessionFactory.putValue(WorkFlowSesisonKey.MASKING_PANEL, this);
}
public static void mask(String text) {
if (text != null)
new NTMaskAlert(text);
else
new NTMaskAlert("Processing");
}
public static void unMask() {
NTMaskAlert alert = (NTMaskAlert) WorkFlowSessionFactory
.getValue(WorkFlowSesisonKey.MASKING_PANEL);
if (alert != null) {
alert.hide();
alert = null;
}
}
public void setDisplayText(String displayText) {
this.displayText = displayText;
alert.setText(displayText);
}
public String getDisplayText() {
return displayText;
}
public void setMessage(String message) {
this.message = message;
lable.setText(message);
}
public String getMessage() {
return message;
}
}
Use static mask and unmask method for operations.

This is my solution:
public class CustomPopupPanel extends PopupPanel {
private Label label = new Label();
public CustomPopupPanel() {
super(false, true); // Create a modal dialog box that will not auto-hide
super.setGlassEnabled(true); // Enable the glass panel
super.add(label); // Add the widget label into the panel
}
public CustomPopupPanel(String text) {
this();
this.mask(text);
}
public final void mask(String text) {
label.setText(text);
super.center(); // Center the popup and make it visible
}
public void unmask() {
super.hide(); // Hide the popup
}
}

Related

Unity3D: How to detect when a button is being held down and released [duplicate]

This question already has answers here:
How to detect click/touch events on UI and GameObjects
(4 answers)
Closed 3 years ago.
I have a UI button. I want to show a text when the user is pressing the button and hide the text when the user releases the button.
How can I do this?
this anwser is basically fine but there is a huge drawback: You can't have additional fields in the Inspector since Button already has a built-in EditorScript which overwrites the default Inspector - You would need to extend this via a custom Inspector every time.
I would instead implement it as completely additional component implementing IPointerDownHandler and IPointerUpHandler (and maybe also IPointerExitHandler to reset also when exiting the button while holding the mouse/pointer still pressed).
For the doing something while the button stays pressed I'ld use a Coroutine.
In general I'ld use UnityEvents:
[RequireComponent(typeof(Button))]
public class PointerDownUpHandler : MonoBehaviour, IPointerDownHandler, IPointerUpHandler, IPointerEnterHandler, IPointerExitHandler
{
public UnityEvent onPointerDown;
public UnityEvent onPointerUp;
// gets invoked every frame while pointer is down
public UnityEvent whilePointerPressed;
private Button _button;
private void Awake()
{
_button = GetComponent<Button>();
}
private IEnumerator WhilePressed()
{
// this looks strange but is okey in a Coroutine
// as long as you yield somewhere
while(true)
{
whilePointerPressed?.Invoke();
yield return null;
}
}
public void OnPointerDown(PointerEventData eventData)
{
// ignore if button not interactable
if(!_button.interactable) return;
// just to be sure kill all current routines
// (although there should be none)
StopAllCoroutines();
StartCoroutine(WhilePressed);
onPointerDown?.Invoke();
}
public void OnPointerUp(PointerEventData eventData)
{
StopAllCoroutines();
onPointerUp?.Invoke();
}
public void OnPointerExit(PointerEventData eventData)
{
StopAllCoroutines();
onPointerUp?.Invoke();
}
// Afaik needed so Pointer exit works .. doing nothing further
public void OnPointerEnter(PointerEventData eventData) { }
}
Than you can reference any callback in onPointerDown, onPointerUp and whilePointerPressed just the way you would do it with the onClick event of the Button.
You have to create your own custom button by extending Button class and override method OnPoiterDown and OnPointerUp.
Attach MyButton component instead of Button to your gameobject
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
public class MyButton : Button
{
public override void OnPointerDown(PointerEventData eventData)
{
base.OnPointerDown(eventData);
Debug.Log("Down");
//show text
}
public override void OnPointerUp(PointerEventData eventData)
{
base.OnPointerUp(eventData);
Debug.Log("Up");
//hide text
}
}

Windows Phone Back button and page instance creation

I need to recreate new page instance on every page load (also when user pressed Back button).
So I overrided OnBackKeyPress method:
protected override void OnBackKeyPress(CancelEventArgs e)
{
base.OnBackKeyPress(e);
if (NavigationService.CanGoBack) {
e.Cancel = true;
var j = NavigationService.RemoveBackEntry();
NavigationService.Navigate(j.Source);
NavigationService.RemoveBackEntry();
}
}
The problem is that I can't handle case when user press back button to close CustomMessageBox dialog. How can I check it? Or is there any way to force recreation of page instance when going back through history state?
Why do you need to recreate the page instance? If you are simply trying to re-read the data to be displayed, why not put the data loading logic into OnNavigatedTo()?
Assuming that is what you are actually trying to achieve, try something like this...
public partial class MainPage : PhoneApplicationPage
{
// Constructor
public MainPage()
{
InitializeComponent();
// don't do your data loading here. This will only be called on page creation.
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
LoadData();
base.OnNavigatedTo(e);
}
MyViewModel model;
async void LoadData()
{
model = new MyViewModel();
await model.LoadDataAsync();
}
}
If you also have specific logic that you need to run on first construction of the page vs. on a back key navigation, check the NavigationMode property of the NavigationEventArgs object that gets passed to OnNavigatedTo.
if(e.NavigationMode == NavigationMode.New)
{
//do what you need to do specifically for a new page instance
}
if (e.NavigationMode == NavigationMode.Back)
{
// do anything specific for back navigation here.
}
Ha, in the near thread, i have opposite question :)
What about MessageBox - it depends, which one are you using. It can be custom message box, for example. Anyway, try to check MessageBox.IsOpened (or alternative for your MessageBox) in your OnBackKeyPress().
Another solution is to use OnNavigatedTo() of the page you want to be new each time.
Third solution: in case you works with Mvvm Light, add some unique id in ViewModel getter, like
public MyViewModel MyViewModel
{
get
{
return ServiceLocator.Current.GetInstance<MyViewModel>((++Uid).ToString());
}
}
This would force to recreate new ViewModel each time, so you'd have different instance of VM, so you would have another data on the View.

How to add DropListener to drop text in a draw2d Label

I am Trying to add a dropListener so I can Drop and text into a draw2d Label ,in GEf Editor , Can anyone help how Can I do that. An example will be great.
To respond to drop events on a GEF edit part viewer you have to install on the viewer itself an implementation of org.eclipse.jface.util.TransferDropTargetListener that understands transfers of type org.eclipse.swt.dnd.TextTransfer and that creates some kind of org.eclipse.gef.Request that can be handled by an org.eclipse.gef.EditPolicy installed on the target org.eclipse.gef.EditPart.
You have to understand that both the Request and the EditPolicy allow you to customize the drop behavior on a EditPart basis. As a consequence, I can show you an example that is actually fully functional, but feel free to customize it to your real needs.
First create the TransferDropTargetListener:
public class TextTransferDropTargetListener extends AbstractTransferDropTargetListener {
public TextTransferDropTargetListener(EditPartViewer viewer) {
super(viewer, TextTransfer.getInstance());
}
#Override
protected void handleDragOver() {
getCurrentEvent().feedback = DND.FEEDBACK_SCROLL | DND.FEEDBACK_EXPAND;
super.handleDragOver();
}
#Override
protected Request createTargetRequest() {
return new ChangeBoundsRequest(REQ_ADD);
}
#Override
protected void updateTargetRequest() {
ChangeBoundsRequest request = (ChangeBoundsRequest) getTargetRequest();
request.setEditParts(Collections.EMPTY_LIST);
request.setLocation(getDropLocation());
}
#Override
protected void handleDrop() {
super.handleDrop();
if (getCurrentEvent().detail != DND.DROP_NONE) {
getViewer().setSelection(StructuredSelection.EMPTY);
getViewer().getControl().setFocus();
}
}
#Override
protected Command getCommand() {
String text = (String) getCurrentEvent().data;
List<IEntityPart> editParts = new ArrayList<IEntityPart>();
//
// using the 'text' variable you have to create
// a new EditPart that would eventually replace the old one.
//
editParts.add(createNewLabelPart());
ChangeBoundsRequest request = (ChangeBoundsRequest) getTargetRequest();
request.setEditParts(editParts);
return super.getCommand();
}
}
then install the listener in the graphical viewer constructor using the following statement:
addDropTargetListener(new TextTransferDropTargetListener(this));
finally ensure that an EditPolicy that understands requests of type REQ_ADD (maybe you already added one that extends LayoutEditPolicy or ContainerEditPolicy) is installed on the target EditPart, which is usually done in the AbstractEditPart.createEditPolicies().
To better understand the chain of responsibilities, I suggest you to have a look at the super implementation of the TransferDropTargetListener.getCommand() method.

How to dismiss a Alert Dialog in Mono for android correctly?

In my application i have a Custom AlertView, which works quite good so far. I can open it the first time, do, what i want to do, and then close it. If i want to open it again, i'll get
java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first
so, here some code:
public Class ReadingTab
{
...
private AlertDialog AD;
...
protected override void OnCreate(Bundle bundle)
{
btnAdd.Click += delegate
{
if (IsNewTask)
{
...
AlertDialog.Builer adb = new AlertDialog.Builer(this);
...
View view = LayoutInflater.Inflate(Resource.Layout.AlertDView15ET15TVvert, null);
adb.setView(view)
}
AD = adb.show();
}
}
}
that would be the rough look of my code.
Inside of btnAdd are two more buttons, and within one of them (btnSafe) i do AD.Dismiss() to close the Alert dialoge, adb.dispose() hasn't done anything.
the first time works fine, but when i call it the secon time, the debugger holds at AD = adb.show(); with the Exception mentioned above.
So what do i have to do, to remove the Dialoge from the parent? i can't find removeView() anywhere.
If you are setting up an AlertView once and then using it in multiple places (especially if you are using the same AlertView across different Activities) then you should consider creating a static AlertDialog class that you can then call from all over the place, passing in the current context as a parameter each time you want to show it. Then when a button is clicked you can simply dismiss the dialog and set the instance to null. Here is a basic example:
internal static class CustomAlertDialog
{
private static AlertDialog _instance;
private const string CANCEL = #"Cancel";
private const string OK = #"OK";
private static EventHandler _handler;
// Static method that creates your dialog instance with the given title, message, and context
public static void Show(string title,
string message,
Context context)
{
if (_instance != null)
{
throw new Exception(#"Cannot have more than one confirmation dialog at once.");
}
var builder = new AlertDialog.Builder(context);
builder.SetTitle(title);
builder.SetMessage(message);
// Set buttons and handle clicks
builder.SetPositiveButton(OK, delegate { /* some action here */ });
builder.SetNegativeButton(CANCEL, delegate { /* some action here */});
// Create a dialog from the builder and show it
_instance = builder.Create();
_instance.SetCancelable(false);
_instance.Show();
}
}
And from your Activity you would call your CustomAlertDialog like this:
CustomAlertDialog.Show(#"This is my title", #"This is my message", this);

lwuit change UI language

I use codenameone to develop my mobile application. In this application I implement some classes and codes manually for instance create all forms by hard coding not using codenameone designer for some reason.
By the way I wanted to navigate in forms like what codenameone use, so I use one variable from type of Form called it prevForm and when I want to open a form I set it to current form and then I show new form.
Ok, that is main scenario. In this application I wanna implement internationalization too, so I create my own hashtable (Farsi and English) for this application.
This is my problem:
How can I set or change language and apply it to forms that I opened?
Is my method for navigate between forms are good?
Here is my code:
public class BaseForm extends Form implements ActionListener {
public BaseForm(){
this.setLayout(new BoxLayout(BoxLayout.Y_AXIS));
}
Command exit, ok, back;
Form prevForm;
protected void initForm(){
}
protected void showForm(){
}
protected void showForm(final Form prevForm){
//String name = this.getName();
//if("Reminder".equals(name) || "3Transaction".equals(name))
{
this.prevForm = prevForm;
Form f = this;
back = new Command("Back");
//ok = new Command("Ok");
//delete = new Command("Delete");;
Button button = new Button("Button");
f.addCommand(back);
//f.addCommand(ok);
//f.addCommand(delete);
//f.addComponent(button);
f.addCommandListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
if (ae.getCommand().equals(back)) {
//Do Exit command code
System.out.println("Back pressed");
prevForm.showBack();
} else if (ae.getCommand().equals(ok)) {
//Do Start command code
System.out.println("Ok pressed");
}
}
});
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
//Do button code
System.out.println("Action performed");
}
});
}
showForm();
}}
for open nested form I use this code:
LanguageUI lang = new LanguageUI();
lang.showForm(this);
change language [form]:
protected boolean onBtnSave() {
if(isRbFarsiSelected()){
UIManager.getInstance().setResourceBundle(new CommonSettings().getFarsi());
}
else {
UIManager.getInstance().setResourceBundle(new CommonSettings().getEnglish());
}
return false;
}
I also hard code my UI on lwuit, and i have a variable parentForm on every class so i can easily show previous form. For language change i know there is Localization in the resource editor that you can make use of. Below is how you can access it. I guess the trick is how to set the content of the L10N in the res file in code? On the other hand you can create your own helper classes that mirror the methods below.
Resources theme = Resources.open("/theme.res");
theme.getL10N(id, locale);
theme.getL10NResourceNames();
theme.isL10N(name);
theme.listL10NLocales(id)

Resources