I have a combobox, that I populate from a web service:
public Configure()
{
InitializeComponent();
WebServiceSoapClient ws = new WebServiceSoapClient();
ws.GetTypesCompleted += new EventHandler<GetTypesCompletedEventArgs>(OnGetTypeCompleted);
ws.GetTypesAsync();
}
void OnGetTypeCompleted(object sender, GetTypesCompletedEventArgs e)
{
if (e.Result != null)
{
List<CodeTableItem> source = e.Result.ToList<CodeTableItem>();
lstType.ItemsSource = source;
lstType.SelectedIndex = -1;
}
}
So when I set the ItemSource property, SelectionChanged event gets fired with SelectedIndex = 0, but user hasn't made this selection yet and I need this list to have no selected value, so I'm setting SelectedIndex to -1, as you can see. As a result, SelectionChanged is called twice.
Can I make it be called only when user selects the item?
Thanks!
I'm using Silverlight 3 and VS 2008
Instead, modify your code so that the SelectionChange event handler isn't defined until after the itemssource and selected index are set.
void OnGetTypeCompleted(object sender, GetTypesCompletedEventArgs e)
{
if (e.Result != null)
{
List<CodeTableItem> source = e.Result.ToList<CodeTableItem>();
lstType.ItemsSource = source;
lstType.SelectedIndex = -1;
lstType.SelectionChanged += new SelectionChangedEventHandler(lstType_SelectionChanged);
}
}
In our application we implemented some code that would set a boolean flag based on the Control.LeftMouseButtonUp() event. When this has been set, it would mean that the user has interacted with the field, and so we can handle the SelectionChanged with different behaviour.
Over the development lifetime of our application this approach was essential so that default bindings would trigger our SelectionChanged logic when we didn't want it to.
If you are an MVVM purist, you'll need to expose the VM as a member variable and then set the bool flag in the VM.
HTH,
Mark
Related
I have created custom data type based on built-in dropdown list, but cannot figure out how to specify default value for the list. The default value is always blank:
The default dropdown does not support default value
There is two way of achieving what you want
create your own dropdown datatype (or use a plugin someone else has made - I am not sure which one support it, but maybe have a look at nuPickers )
since it is your custom made you can control it. More about how to create one checkout doc Tutorial - Creating a property editor
use a web api handler to intercept the call of getting the content value - and set a default value to your property if it is empty (null)
below is some un-tested code:
first create the web api handler
public class SetDropdownDefaultHandler : DelegatingHandler
{
protected override async Task<HttpResponseMessage> SendAsync
(HttpRequestMessage request, CancellationToken cancellationToken)
{
var response = await base.SendAsync(request, cancellationToken);
var url = request?.RequestUri?.AbsolutePath.ToLower;
// only process when a create (getempty) or editing a specific content (getbyid)
if (url == "/umbraco/backoffice/umbracoapi/content/getempty"
|| url == "/umbraco/backoffice/umbracoapi/content/getbyid")
{
var content = (ObjectContent)response.Content;
var data = content?.Value as PagedResult<ContentItemBasic<ContentPropertyBasic, IContent>>;
if (data?.Items != null)
{
var tempResult = data?.Items?.ToList();
foreach (var item in tempResult)
{
foreach (var prop in item?.Properties?.Where(p => p?.Editor == "Umbraco.DropDown"))
{
var propStr = prop.Value?.ToString();
if (!propStr.IsNullOrWhiteSpace())
{
// set your default value if it is empty
prop.Value = "your default option prevalue id";
}
}
}
data.Items = tempResult;
}
}
return response;
}
}
then register it at started event
public class UmbracoEvent : ApplicationEventHandler
{
protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
{
GlobalConfiguration.Configuration.MessageHandlers.Add(new SetDropdownDefaultHandler());
}
}
your problem maybe you don't know your prevalueid - you can look it up in db or you could use datatype service to get the datatype prevalues then decide which to put as default
Look at: FieldType.DropDownList in the fieldTypes folder.
Replace:<option value=""></option>
With:
var settings = Model.AdditionalSettings;
<option value="">#settings["DefaultValue"]</option>
Then ensure you set the default value property in your dropdown list in the Umbraco Forms backoffice for the given form
I am using a DevExpress MVC Pivot Grid and trying to work out some problems with the loading and saving of layouts. So far I have the following:
I have set my CustomActionRouteValues in the PivotGridSettings as follows:
CustomActionRouteValues = new { Controller = "Home", Action = "PivotGridCustomCallback" },
Which points to the following:
public ActionResult PivotGridCustomCallback(string action, string reportName)
{
if (string.IsNullOrEmpty(reportName))
{
reportName = "Report 1";
}
var settings = PivotGridLayoutHelper.DefaultPivotGridSettings;
if (action == "Save")
{
// TODO: Find a better solution than this. At the moment, if Save is called once, it is then called again every time the user changes the layout.. which is why we have the 'saved' variable here.
bool saved = false;
settings.AfterPerformCallback = (sender, e) =>
{
if (saved)
{
return;
}
SaveLayout(((MVCxPivotGrid)sender).SaveLayoutToString(), reportName);
saved = true;
};
}
else if (action == "Load")
{
// TODO: Find a better solution than this. At the moment, if Load is called once, it is then called again every time the user changes the layout.. which is why we have the 'loaded' variable here.
bool loaded = false;
string layoutString = LoadLayout(reportName);
if (!string.IsNullOrEmpty(layoutString))
{
settings.BeforeGetCallbackResult = (sender, e) =>
{
if (loaded)
{
return;
}
((MVCxPivotGrid)sender).LoadLayoutFromString(layoutString, PivotGridWebOptionsLayout.DefaultLayout);
loaded = true;
};
}
}
ViewBag.PivotSettings = settings;
return PartialView("PivotPartial");
}
The problem, as you can see in the code comments, is that after performing an action just one time, it then gets called EVERY time I make any sort of change. So, for example... say I load a report.. that's fine.. but then when I try expand something or add a field.. or do ANYTHING, nothing seems to happen on the UI.. and I figured out that's because immediately, this code gets called again:
settings.BeforeGetCallbackResult = (sender, e) =>
{
((MVCxPivotGrid)sender).LoadLayoutFromString(layoutString, PivotGridWebOptionsLayout.DefaultLayout);
};
That just keeps resetting the values to the saved layout, which means the UI looks like it's unresponsive when trying to change anything.
This is why I now have the boolean variable called loaded to check if it's already loaded. That works.. but it's an ugly hack.. because it's making unnecessary trips to the server each and every time the user does anything on the pivot grid.
Surely there must be a way to prevent these actions from firing all the time?
I've read several related posts and even posted and answer here but it seems like I was not able to solve the problem.
I have 3 Activities:
Act1 (main)
Act2
Act3
When going back and forth Act1->Act2 and Act2->Act1 I get no issues
When going Act2->Act3 I get no issues
When going Act3->Act2 I get occasional crashes with the following error: java.lang.IllegalStateException: trying to requery an already closed cursor android.database.sqlite.SQLiteCursor#.... This is a ListView cursor.
What I tried:
1. Adding stopManagingCursor(currentCursor);to the onPause() of Act2 so I stop managing the cursor when leaving Act2 to Act3
protected void onPause()
{
Log.i(getClass().getName() + ".onPause", "Hi!");
super.onPause();
saveState();
//Make sure you get rid of the cursor when leaving to another Activity
//Prevents: ...Unable to resume activity... trying to requery an already closed cursor
Cursor currentCursor = ((SimpleCursorAdapter)getListAdapter()).getCursor();
stopManagingCursor(currentCursor);
}
When returning back from Act3 to Act2 I do the following:
private void populateCompetitorsListView()
{
ListAdapter currentListAdapter = getListAdapter();
Cursor currentCursor = null;
Cursor tournamentStocksCursor = null;
if(currentListAdapter != null)
{
currentCursor = ((SimpleCursorAdapter)currentListAdapter).getCursor();
if(currentCursor != null)
{
//might be redundant, not sure
stopManagingCursor(currentCursor);
// Get all of the stocks from the database and create the item list
tournamentStocksCursor = mDbHelper.retrieveTrounamentStocks(mTournamentRowId);
((SimpleCursorAdapter)currentListAdapter).changeCursor(tournamentStocksCursor);
}
else
{
tournamentStocksCursor = mDbHelper.retrieveTrounamentStocks(mTournamentRowId);
}
}
else
{
tournamentStocksCursor = mDbHelper.retrieveTrounamentStocks(mTournamentRowId);
}
startManagingCursor(tournamentStocksCursor);
//Create an array to specify the fields we want to display in the list (only name)
String[] from = new String[] {StournamentConstants.TblStocks.COLUMN_NAME, StournamentConstants.TblTournamentsStocks.COLUMN_SCORE};
// and an array of the fields we want to bind those fields to (in this case just name)
int[] to = new int[]{R.id.competitor_name, R.id.competitor_score};
// Now create an array adapter and set it to display using our row
SimpleCursorAdapter tournamentStocks = new SimpleCursorAdapter(this, R.layout.competitor_row, tournamentStocksCursor, from, to);
//tournamentStocks.convertToString(tournamentStocksCursor);
setListAdapter(tournamentStocks);
}
So I make sure I invalidate the cursor and use a different one. I found out that when I go Act3->Act2 the system will sometimes use the same cursor for the List View and sometimes it will have a different one.
This is hard to debug and I was never able to catch a crashing system while debugging. I suspect this has to do with the time it takes to debug (long) and the time it takes to run the app (much shorter, no pause due to breakpoints).
In Act2 I use the following Intent and expect no result:
protected void onListItemClick(ListView l, View v, int position, long id)
{
super.onListItemClick(l, v, position, id);
Intent intent = new Intent(this, ActivityCompetitorDetails.class);
intent.putExtra(StournamentConstants.App.competitorId, id);
intent.putExtra(StournamentConstants.App.tournamentId, mTournamentRowId);
startActivity(intent);
}
Moving Act1->Act2 Act2->Act1 never gives me trouble. There I use startActivityForResult(intent, ACTIVITY_EDIT); and I am not sure - could this be the source of my trouble?
I would be grateful if anyone could shed some light on this subject. I am interested in learning some more about this subject.
Thanks,D.
I call this a 2 dimensional problem: two things were responsible for this crash:
1. I used startManagingCursor(mItemCursor); where I shouldn't have.
2. I forgot to initCursorAdapter() (for autocomplete) on onResume()
//#SuppressWarnings("deprecation")
private void initCursorAdapter()
{
mItemCursor = mDbHelper.getCompetitorsCursor("");
startManagingCursor(mItemCursor); //<= this is bad!
mCursorAdapter = new CompetitorAdapter(getApplicationContext(), mItemCursor);
initItemFilter();
}
Now it seems to work fine. I hope so...
Put this it may work for you:
#Override
protected void onRestart() {
// TODO Auto-generated method stub
super.onRestart();
orderCursor.requery();
}
This also works
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB) {
startManagingCursor(Cursor);
}
I have written an add in that takes the active document as a parameter. So each time that the active document has changed, I need to know. To do so, I wanted to use "Events.DocumentEvents.DocumentOpened" event of the DTE2 object. But the problem is that event is never get fired even though I change the active document.
The code snippet is as follows
public void OnConnection(object application, ext_ConnectMode connectMode, object addInInst, ref Array custom)
{
_applicationObject = (DTE2)application;
_applicationObject.Events.DocumentEvents.DocumentOpened += new _dispDocumentEvents_DocumentOpenedEventHandler(DocumentEvents_DocumentOpened);
...
}
void DocumentEvents_DocumentOpened(Document Document)
{
MessageBox.Show("Not called");
}
I have tried with DocumentEvents as well but no success. Any ideas?
I had just realized that I focused on the wrong event and thats why it was not fired. With the code below I got what I intended to. So instead of DocumentEvents, I had to use WindowEvents.
....
_applicationObject.Events.WindowEvents.WindowActivated += new _dispWindowEvents_WindowActivatedEventHandler(WindowEvents_WindowActivated);
}
void WindowEvents_WindowActivated(Window GotFocus, Window LostFocus)
{
if (ucCAST != null && GotFocus.Document != null)
((CAST)ucCAST).refreshCode(GotFocus.Document.Name);
}
I am writing an Excel 2007 Addin. using VS2008 and .net 3.5, C#.
I catched Microsoft.Office.Interop.Excel.Application's WindowActivate and WindowDeActivate events.
It was surprised to know that WindowActivate and Deactivate only triggers when i switch between two Excel Windows. if i switch to notepad, i expect Deactivate to be triggered, but its not happening. same way from notepad if i switch to excel window, i expect Activate to be triggered but its not happening. It looks like the behaviour indicates windows are MDI-Child windows.
Now what i want to do is get HWnd of Excel's Mainwindow and hook Window Activate and Deactivates using dllimport features.
Can anyone guide to me on this.
Regards
I solved similar problem when writing Excel addin. No dll import is needed. I solved this issue using System.Windows.Forms.NativeWindow class.
At first, I made my own class inherited from NativeWindow class and declared two events Activated and Deactivate in it and finaly overrided WndProc() method to rise these events when message WM_ACTIVATE is passed to the WndProc method. According to "Message" parameter WParm is Excel window activated or deactivated.
public class ExcelWindow: NativeWindow
{
public const int WM_ACTIVATED = 0x0006;
public ExcelWindow():base(){}
//events
public event EventHandler Activated;
public event EventHandler Deactivate;
//catching windows messages
protected override void WndProc(ref Message m)
{
if (m.Msg== WM_ACTIVATED)
{
if (m.WParam.ToInt32() == 1)
{
//raise activated event
if (Activated!=null)
{
Activated(this, new EventArgs());
}
}
else if (m.WParam.ToInt32() == 0)
{
//raise deactivated event
if (Deactivate!=null)
{
Deactivate(this, new EventArgs());
}
}
}
base.WndProc(ref m);
}
}
Then I made in my addin class field "ExcelWindow myExcelWindow" and added following code to OnConnection method of my addin:
ExcelWindow myExcelWindow;
void Extensibility.IDTExtensibility2.OnConnection(object application, Extensibility.ext_ConnectMode ConnectMode, object AddInInst, ref Array custom)
{
excel = application as Excel.Application;
myExcelWindow = new ExcelWindow();
myExcelWindow.AssignHandle(new IntPtr(excel.Hwnd));
myExcelWindow.Activated += new EventHandler(myExcelWindow_Activated);
myExcelWindow.Deactivate += new EventHandler(myExcelWindow_Deactivate);
//addin code here
}
void myExcelWindow_Activated(object sender, EventArgs e)
{
//do some stuff here
}
void myExcelWindow_Deactivate(object sender, EventArgs e)
{
//do some stuff here
}
I hope this will help you.
Finally I found one solution..that works only Activate/Deactivate.
This is not the perfect way to do it. But I did not find any good alternative.
This method uses polling. I have to call following function in each 10 ms interval to check focus in/out.
public static bool ApplicationIsActivated()
{
var activatedHandle = GetForegroundWindow();
if (activatedHandle == IntPtr.Zero)
{
return false; // No window is currently activated
}
var procId = Process.GetCurrentProcess().Id;
int activeProcId;
GetWindowThreadProcessId(activatedHandle, out activeProcId);
return activeProcId == procId;
}