OnPropertyChanged reaction different the first time and the second time - wpf

I have got a collection of viewModels(InputViewModel) in an other viewModel(ScenarioManager).
each InputviewModel has an instance of a Class(RestOfInput) which contains properties able to raise the OnPropertyChanged.
when one of these properties changes the event is handled by this method (in InputViewModel) :
public void TestAfterChanges(object sender, PropertyChangedEventArgs e)
{
MessageBox.Show("not ref");
bool isInTheList = false;
RestOfInput roi = sender as RestOfInput;
string prop = e.PropertyName;
if (prop!="NameFile")
{
Difference d = new Difference();
d.Length = prop;
d.Value1 = reference.RoI.getValueByPropertyName(prop);
d.Value2 = roi.getValueByPropertyName(prop);
foreach (Difference diff in _ListOfDifferences)
{
if (diff.Length==prop)
{
if ( (Math.Abs(d.Value2-d.Value1)>0.001*d.Value1))
{
//replace by le new one
_ListOfDifferences.Insert(_ListOfDifferences.IndexOf(diff), d);
_ListOfDifferences.Remove(diff);
}
else
{
//if change make the field value equal to the ref then remove from difference list
_ListOfDifferences.Remove(diff);
}
isInTheList = true;
}
}
if ((Math.Abs(d.Value2 - d.Value1) > 0.001 * d.Value1) && isInTheList==false)
{
_ListOfDifferences.Add(d);
}
}
}
this method gives just a summary of the differences between this particular case and the reference case.
Now if the reference case changes I have to update all the cases and the event is handled
in ScenarioManager :
public void refCaseChanging(object sender, PropertyChangedEventArgs e)
{
MessageBox.Show("ref");
string propname = e.PropertyName;
foreach (InputViewModel item in _casesList)
{
if (item!=inpVM)
{
item.RoI.OnPropertyChanged(propname);
}
}
}
inpVM is the reference case.
Then I have this behavior :
-if I change a field in a case which is not the reference case : everything is ok.
-if I change a particular field in the reference case : the first time, everything is ok.
But the second time, only the reference case and the first case (in the collection) which is not the reference case are updated>
It is like the foreach loop is broken..
Any explications.
If the message is not clear please tell me ( not easy to explain ;) )

An exception could explain that processing stops (although one expects that it would be caught and displayed somewehre).
Have you tried to ask VS to halt your program when an exception is thrown ? (if you have never done this before, go to Debug / Exceptions and check the check box for CLR exceptions)

Related

in flink processFunction, all mapstate is empty in onTimer() function

I want implements the aggregationFunction by the processKeyedFunction, because the default aggregationFunction does not support rich function,
Besides, I tryed the aggreagationFunction + processWindowFunction(https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/operators/windows.html), but it also cannot satisfy my needs, so I have to use the basic processKeyedFunction to implement the aggregationFunction, the detail of my problem is as followed:
in processFunction, , I define a windowState for stage the aggregation value of elements, the code is as followed:
public void open(Configuration parameters) throws Exception {
followCacheMap = FollowSet.getInstance();
windowState = getRuntimeContext().getMapState(windowStateDescriptor);
currentTimer = getRuntimeContext().getState(new ValueStateDescriptor<Long>(
"timer",
Long.class
));
in processElement() function, I use the windowState (which is a MapState initiate in open function) to aggregate the window element, and register the first timeServie to clear current window state, the code is as followed:
#Override
public void processElement(FollowData value, Context ctx, Collector<FollowData> out) throws Exception
{
if ( (currentTimer==null || (currentTimer.value() ==null) || (long)currentTimer.value()==0 ) && value.getClickTime() != null) {
currentTimer.update(value.getClickTime() + interval);
ctx.timerService().registerEventTimeTimer((long)currentTimer.value());
}
windowState = doMyAggregation(value);
}
in onTimer() function, first, I register the next timeService in next One minute, and clear the window State
#Override
public void onTimer(long timestamp, OnTimerContext ctx, Collector<FollowData> out) throws Exception {
currentTimer.update(timestamp + interval); // interval is 1 minute
ctx.timerService().registerEventTimeTimer((long)currentTimer.value());
out.collect(windowState);
windowState.clear();
}
but when the program is running , I found that all the windowState in onTimer is empty, but it is not empyt in processElement() function, I don't know why this happens, maybe the execution logic is different, how can I fix this,
Thanks in advance !
new added code about doMyAggregation() part
windowState is a MapState , key is "mykey", value is an self-defined Object AggregateFollow
public class AggregateFollow {
private String clicked;
private String unionid;
private ArrayList allFollows;
private int enterCnt;
private Long clickTime;
}
and the doMyAggregation(value) function is pretty much like this , the function of doMyAggregation is to get all the value whose source field is 'follow', but if there are no values whose field is 'click' during 1 minute, the 'follow' value should be obsolete, in a word , it's like a join operation of 'follow' data and 'click' data,
AggregateFollow acc = windowState.get(windowkey);
String flag = acc.getClicked();
ArrayList<FollowData> followDataList = acc.getAllFollows();
if ("0".equals(flag)) {
if ("follow".equals(value.getSource())) {
followDataList.add(value);
acc.setAllFollows(followDataList);
}
if ("click".equals(value.getSource())) {
String unionid = value.getUnionid();
clickTime = value.getClickTime();
if (followDataList.size() > 0) {
ArrayList listNew = new ArrayList();
for (FollowData followData : followDataList) {
followData.setUnionid(unionid);
followData.setClickTime(clickTime);
followData.setSource("joined_flag"); //
}
acc.setAllFollows(listNew);
}
acc.setClicked("1");
acc.setUnionid(unionid);
acc.setClickTime(clickTime);
windowState.put(windowkey, acc);
}
} else if ("1".equals(flag)) {
if ("follow".equals(value.getSource())) {
value.setUnionid(acc.getUnionid());
value.setClickTime(acc.getClickTime());
value.setSource("joined_flag");
followDataList.add(value);
acc.setAllFollows(followDataList);
windowState.put(windowkey, acc);
}
}
because of performance problem, original windowAPI is not a valid choice for me, the only way here I think is to use processFunction + ontimer and Guava Cache ,
Thanks a lot
If windowState is empty, it would be helpful to see what doMyAggregation(value) is doing.
It's difficult to debug this, or propose good alternatives, without more context, but out.collect(windowState) isn't going to work as intended. What you might want to do instead would be to iterate over this MapState and collect each key/value pair it contains to the output.
I changed the type of windowState from MapState to ValueState, and the problem is solved, maybe it is a bug or something, can anyone can explain this?

Scrolling in Sticky Notes

I got the following sticky note example:
If the sticky note has more than 9 rows, the additional rows are not visible.
I'm able to navigate through the note with my arrow keys. If I'm going to scroll with the mouse wheel, it seems to ignore the popup and just changes the page.
Is it possible to activate scrolling for sticky note popups?
Edit:The solution outlined below will soon be available as part of the samples included in the PDFTron SDK download. In the meanwhile, I hope that the below solution helps.
Yes, it is possible to activate scrolling for sticky notes.
The problem is most apparent when using the single page view. It appears to work as expected in continuous mode.
However it is not as simple as setting VerticalScrollVisibility = ScrollBarVisibility.Auto;. There are a few files that need to be modified to get this working.
The good news is that we can get the expected behaviour by modifying the code in the provided samples.
Solution
The solution is to add some handling for the PreviewMouseWheel event coming from the PDFViewWPF class.
In the downloaded samples, the following changes were made to get things running as expected:
Add a method to handle the PreviewMouseWheel event in the NoteHost class (Samples/PDFViewWPFTools/CS/Utilities/NoteHost.cs)
internal void HandlePreviewMouseWheel(object sender, MouseWheelEventArgs e)
{
var originalSource = (UIElement)e.OriginalSource;
if (originalSource.IsDescendantOf(mNoteBorder) && mTextBox.IsFocused)
{
mTextBox.ScrollToVerticalOffset(mTextBox.VerticalOffset - e.Delta);
e.Handled = true;
}
}
Also make sure to add mTextBox.VerticalScrollBarVisibility = ScrollBarVisibility.Auto; in the NoteHost.CreateNoteAndArrow() method, after the mTextBox object is instantiated (~line 183).
Next, edit the NoteManager class - Samples/PDFViewWPFTools/CS/Utilities/NoteManager.cs - and add a HandlePreviewMouseWheel method. This will internally call the HandlePreviewMouseWheel on each displayed (opened) note and break at the first one where the event gets handled.
internal void HandlePreviewMouseWheel(object sender, System.Windows.Input.MouseWheelEventArgs e)
{
foreach(var note in mActiveNotes)
{
note.Value.HandlePreviewMouseWheel(sender, e);
if(e.Handled)
{
break;
}
}
}
Next, edit the ToolManager class to ensure that the note manager gets a chance to handle the PreviewMouseWheel before attempting a page change. Open Samples/PDFViewWPFTools/CS/ToolManager.cs and navigate to the PDFView_PreviewMouseWheel. The existing method should look like this:
private void PDFView_PreviewMouseWheel(object sender, System.Windows.Input.MouseWheelEventArgs e)
{
if (mCurrentTool != null && _IsEnabled)
{
ToolManager.ToolType prev_tm = mCurrentTool.ToolMode;
ToolManager.ToolType next_tm;
while (true)
{
mCurrentTool.PreviewMouseWheelHandler(sender, e);
next_tm = mCurrentTool.NextToolMode;
if (prev_tm != next_tm)
{
mCurrentTool = CreateTool(next_tm, mCurrentTool);
prev_tm = next_tm;
}
else
{
break;
}
}
}
}
Replace it with the below code:
private void PDFView_PreviewMouseWheel(object sender, System.Windows.Input.MouseWheelEventArgs e)
{
if (mCurrentTool != null && _IsEnabled)
{
ToolManager.ToolType prev_tm = mCurrentTool.ToolMode;
ToolManager.ToolType next_tm;
while (true)
{
mNoteManager.HandlePreviewMouseWheel(sender, e);
if (!e.Handled)
{
mCurrentTool.PreviewMouseWheelHandler(sender, e);
next_tm = mCurrentTool.NextToolMode;
if (prev_tm != next_tm)
{
mCurrentTool = CreateTool(next_tm, mCurrentTool);
prev_tm = next_tm;
}
else
{
break;
}
}
else
{
break;
}
}
}
}
By doing the above, we are giving the NoteManager a chance to handle the PreviewMouseWheel before doing anything else with it.
Another point to note is that we have to now "do the scrolling" in code, using the mTextBox.ScrollToVerticalOffset method in the NoteHost class.

IWeakEventListener.ReceiveWeakEvent() called multiple times when PropertyChanged(null) is called on source object

I'm using the PropertyObserver class in my code to avoid doing string comparisons in PropertyChanged event handling and factor out the handling of null or string.Empty as its argument (Which indicates that all properties of an object has changed).
This class uses PropertyChangedEventManager to register callbacks in the target object and implements IWeakEventListener to respond every time PropertyChanged event is invoked on the source object.
But during the creation of a unit test I found out that the IWeakEventListener.ReceiveWeakEvent() is called N number of times, with N as the number of the registered callbacks. This only occurs when null or string.Empty is specified, not when a valid property name is given in the PropertyChanged event.
Does anyone knows why this is happening and how to fix it? My goal is to do a foreach of the registered handlers ONE time when null is given, so I can update my target object by getting all the properties of the source object. But when ReceiveWeakEvent() is called N times then the foreach will be repeated N times!
To illustrate it, the following is a simplified version of the PropertyObserver class and the source class (I'm using MVVM Light's ObservableObject for INotifyPropertyChanged implementation):
public class PropertyObserver : IWeakEventListener {
public bool ReceiveWeakEvent(Type managerType, object sender, EventArgs e) {
if (managerType == typeof(PropertyChangedEventManager)) {
string propertyName = ((PropertyChangedEventArgs)e).PropertyName;
if (string.IsNullOrEmpty(propertyName)) {
Console.WriteLine ("Foreach registered handlers and invoke one by one");
} else {
Console.WriteLine ("Invoke handler for property {0}", propertyName);
}
return true;
}
return false;
}
}
public class ViewModel : ObservableObject {
private int mProp1;
private int mProp2;
public int Prop1 {
get { return mProp1; }
set {
mProp1 = value;
RaisePropertyChanged("Prop1");
}
}
public int Prop2 {
get { return mProp2; }
set {
mProp2 = value;
RaisePropertyChanged("Prop2");
}
}
public void RaiseAllPropertyChanged() {
RaisePropertyChanged(null);
}
}
And in a console app's Main we can call them like so:
var vm = new ViewModel();
var obs = new PropertyObserver();
// Normally this is done inside the PropertyObserver class.
PropertyChangedEventManager.AddListener(vm, obs, "Prop1");
PropertyChangedEventManager.AddListener(vm, obs, "Prop2");
vm.Prop1 = 1; // Results in a console line "Invoke handler for property Prop1"
vm.Prop2 = 2; // Results in a console line "Invoke handler for property Prop2"
// Results in two console lines: "Foreach registered handlers and invoke one by one", expected is only 1!
vm.RaiseAllPropertyChanged();
Okay, I didn't understand the AddListener() method before. I only need to register a listener once:
PropertyChangedEventManager.AddListener(vm, obs, string.Empty);
to listen to all PropertyChanged events of a source object. Doing this will produce the correct working of the PropertyObserver class:
vm.Prop1 = 1; // "Invoke handler for property Prop1"
vm.Prop2 = 2; // "Invoke handler for property Prop2"
// Now results in one console line "Foreach registered handlers and invoke one by one"
vm.RaisePropertyChanged();
Each registered listener with non-empty third argument (the property name) will respond to only the specified property name and null or string.Empty. So that's why the foreach was invoked twice on the original code.

How to move by code the BindingSource to a specific record

Using datagridview bound to BindingSource control bound to a LINQ to SQL class, I wonder how to position the bindingSource to a specific record, that is, when I type a Product name in a textbox, the bindingsource should move to that specific product. Here is my code:
In my form FrmFind:
NorthwindDataContext dc;
private void FrmFind_Load(object sender, EventArgs e)
{
dc = new NorthwindDataContext();
var qry = (from p in dc.Products
select p).ToList();
FindAbleBindingList<Product> list = new FindAbleBindingList<Product>(qry);
productBindingSource.DataSource = list.OrderBy(o => o.ProductName);
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
TextBox tb = sender as TextBox;
int index = productBindingSource.Find("ProductName", tb.Text);
if (index >= 0)
{
productBindingSource.Position = index;
}
}
In the program class:
public class FindAbleBindingList<T> : BindingList<T>
{
public FindAbleBindingList()
: base()
{
}
public FindAbleBindingList(List<T> list)
: base(list)
{
}
protected override int FindCore(PropertyDescriptor property, object key)
{
for (int i = 0; i < Count; i++)
{
T item = this[i];
//if (property.GetValue(item).Equals(key))
if (property.GetValue(item).ToString().StartsWith(key.ToString()))
{
return i;
}
}
return -1; // Not found
}
}
How can I implement the find method to make it work?
You can combine the BindingSource.Find() method with the Position property.
For example, if you have something like this in your TextBox changed event handler:
private void textBox1_TextChanged(object sender, EventArgs e)
{
TextBox tb = sender as TextBox;
int index = bs.Find("Product", tb.Text);
if (index >= 0)
{
bs.Position = index;
}
}
This of course will depend on a lot of things like the particular implementation of the Find method the data source for the binding source has.
In a question you asked a little while ago I gave you an implementation for Find which worked with full matches. Below is a slightly different implementation that will look at the start of the property being inspected:
protected override int FindCore(PropertyDescriptor property, object key)
{
// Simple iteration:
for (int i = 0; i < Count; i++)
{
T item = this[i];
if (property.GetValue(item).ToString().StartsWith(key.ToString()))
{
return i;
}
}
return -1; // Not found
}
Do note that the above method is case sensitive - you can change StartsWith to be case insensitive if you need.
One key thing to note about the way .Net works is that the actual type of an object is not sufficient all the time - the declared type is what consuming code knows about.
This is the reason why you get a NotSupported exception when calling the Find method, even though your BindingList implementation has a Find method - the code that receives this binding list doesn't know about the Find.
The reason for that is in these lines of code:
dc = new NorthwindDataContext();
var qry = (from p in dc.Products
select p).ToList();
FindAbleBindingList<Product> list = new FindAbleBindingList<Product>(qry);
productBindingSource.DataSource = list.OrderBy(o => o.ProductName);
When you set the data source for the binding source you include the extension method OrderBy - Checking this shows that it returns IOrderedEnumerable, an interface described here on MSDN. Note that this interface has no Find method, so even though the underlying FindableBindingList<T> supports Find the binding source doesn't know about it.
There are several solutions (the best is in my opinion to extend your FindableBindingList to also support sorting and sort the list) but the quickest for your current code is to sort earlier like so:
dc = new NorthwindDataContext();
var qry = (from p in dc.Products
select p).OrderBy(p => p.ProductName).ToList();
FindAbleBindingList<Product> list = new FindAbleBindingList<Product>(qry);
productBindingSource.DataSource = list;
In WinForms there are no entirely out of the box solutions for the things you are trying to do - they all need a little bit of custom code that you need to put together to match just your own requirements.
I took a different approach. I figured, programmatically, every record must be checked until a match is found, so I just iterated using the MoveNext method until I found a match. Unsure if the starting position would be the First record or not, so I used the MoveFirst method to ensure that is was.
There is one assumption, and that is that what you are searching for is unique in that column. In my case, I was looking to match an Identity integer.
int seekID;
this.EntityTableBindingSource.MoveFirst();
if (seekID > 0)
{
foreach (EntityTable sd in EntityTableBindingSource)
{
if (sd.ID != seekID)
{
this.t_EntityTableBindingSource.MoveNext();
}
else
{
break;
}
}
}
I didn't really care for either answer provided. Here is what I came up with for my problem:
// Create a list of items in the BindingSource and use labda to find your row:
var QuickAccessCode = customerListBindingSource.List.OfType<CustomerList>()
.ToList().Find(f => f.QuickAccessCode == txtQAC.Text);
// Then use indexOf to find the object in your bindingSource:
var pos = customerListBindingSource.IndexOf(QuickAccessCode);
if (pos < 0)
{
MessageBox.Show("Could not find " + txtQAC.Text);
}
else
{
mainFrm.customerListBindingSource.Position = pos;
}

System.Printing.PrintQueue QueueStatus not updating

Is there a way to update the print queue status information contained in the PrintQueue object?
I've tried calling Refresh on the PrintQueue object but that doesn't really do anything. For instance, I've turned off the printer and the Control Panel correctly shows the printer as "Offline", however the QueueStatus property, as well as the IsOffline property don't reflect that - no matter how many times I call Refresh on both the PrintServer and the PrintQueue in question.
I've seen examples of how to get status information using WMI queries but I wonder - since these properties are available on the PrintQueue object - whether there is any way to use those.
After try to print your PrintDocument (System.Drawing.Printing), try to check status of printjobs.
First step:
Initialize your printDocument.
Second step:
Get your printer Name From System.Drawing.Printing.PrinterSettings.InstalledPrinters.Cast<string>();
And copy it into your printerDocument.PrinterSettings.PrinterName
Third step:
Try to print and dispose.
printerDocument.Print();
printerDocument.Dispose();
Last step: Run the check in a Task (do NOT block UI thread).
Task.Run(()=>{
if (!IsPrinterOk(printerDocument.PrinterSettings.PrinterName,checkTimeInMillisec))
{
// failed printing, do something...
}
});
Here is the implementation:
private bool IsPrinterOk(string name,int checkTimeInMillisec)
{
System.Collections.IList value = null;
do
{
//checkTimeInMillisec should be between 2000 and 5000
System.Threading.Thread.Sleep(checkTimeInMillisec);
using (System.Management.ManagementObjectSearcher searcher = new System.Management.ManagementObjectSearcher("SELECT * FROM Win32_PrintJob WHERE Name like '%" + name + "%'"))
{
value = null;
if (searcher.Get().Count == 0) // Number of pending document.
return true; // return because we haven't got any pending document.
else
{
foreach (System.Management.ManagementObject printer in searcher.Get())
{
value = printer.Properties.Cast<System.Management.PropertyData>().Where(p => p.Name.Equals("Status")).Select(p => p.Value).ToList();
break;
}
}
}
}
while (value.Contains("Printing") || value.Contains("UNKNOWN") || value.Contains("OK"));
return value.Contains("Error") ? false : true;
}
Good luck.

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