binding

问题 There is a known bug in the standard WPF DataGrid when the user clicks on the last row to add a new row. An exception is thrown because a ConvertBack method (on the default converter) fails when dealing with the MS.Internal.NamedObject that represents the 'NewItemPlaceholder'. This instance is used to represent the blank “new row” if CanUserAddRows is set to True (and the collection supports it). In fact it appears as if the FormatException is actually being thrown within an exception handler

问题 I'm working through the book Structure and implementation of computer programs and in one of the chapters there were some code used to calculate the factorial of a number: (define (factorial n) (fact-iter 1 1 n)) (define (fact-iter product counter max-count) (if (> counter max-count) product (fact-iter (* counter product) (+ counter 1) max-count))) Earlier in the book I learned that I can define functions inline in another function like this: (define (factorial n) (define (fact-iter product

问题 I was writing a simple login form, everything works fine (validation etc.) but I can't get the values, there's my code: public function executeIndex(sfWebRequest $request) { $this->getUser()->clearCredentials(); $this->getUser()->setAuthenticated(false); $this->form = new LoginForm(); if ($request->isMethod('post') && $request->hasParameter('login')) { $this->form->bind($request->getParameter('login')); if ($this->form->isValid()) { $this->getUser()->setAuthenticated(true); $this->getUser()-

问题 I have MediaElement and Slider. How I can bind MediaElement.Position to Slider.Value without DispatcherTimer? 回答1: OK SO this COULD be that : <Slider x:Name="PositionSlider" Minimum="0" Maximum="{Binding ElementName=mediaElement, Path=mediaElement.NaturalDuration.TimeSpan.TotalMilliseconds}" /> <MediaElement x:Name="mediaElement" Position="{Binding Value, ElementName=PositionSlider, Converter={StaticResource MyMsToTimeSpanConverter}}" /> !! BUT !! Position is not a dependency property, so you

问题 I am using a data table created mostly with css that I found online. In one of the columns there is a css data attribute "data-title" which is assigned a string. <td data-title="someString"> When I enter a string, the styling inside the column works as expected. When I try to bind to an objects string, the binding doesn't work like I would expect. I tried <td data-title="object.someString"> which just displays literal 'object.someString' and I tried <td data-title="{{object.someString}}">

问题 I'm having problems binding a command to a menuitem in a compositecollection. The MenuItem is part of ContextMenu which is defined in the UserControl.Resources . The problem is that the binding of the New label is not working. When I place the MenuItem outside of the composite collection it will work. Any ideas? <UserControl.Resources> <ContextMenu x:Key="DataGridRowContextMenu"> <MenuItem Header=" Set label"/> <MenuItem.ItemsSource> <CompositeCollection> <CollectionContainer Collection="

问题 I have a DataGrid which has a DataGridTemplateColumn that uses the ItemsSource binding of the DataGrid, but in the ComboBox of the DataGridTemplateColumn, I want to be able to bind to the ViewModel for the View instead of the ItemsSource. <DataGrid ItemsSource="{Binding ModelValues, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" > <DataGridTemplateColumn Header="myHeader" Width="200"> <DataGridTemplateColumn.CellTemplate> <DataTemplate> <ComboBox DisplayMemberPath="Value"

问题 i am using facelets jsf 2.0 with primefaces 3.0.M2 component library. i am trying to achieve dynamic numbers of rows including iput fields that are filled when a datatable selection occurs. whenever a selection is made the dynamic rows generated correctly with input fields but after the first selection for following selections dynamic row count changes correctly but the input fields does not update and keeps showing inputs from the first selection. here is how i iterate list in facelet; <ui

问题 I am working with Tkinter in Python 3.5 and I encounter a weird problem. I used the tkinterbook about events and bindings to write this simple example: from tkinter import * root = Tk() frame = Frame(root, width=100, height=100) def callback(event): print("clicked at", event.x, event.y) # frame.unbind("<Button-1>", callback) frame.bind("<Button-1>", callback) frame.pack() root.mainloop() It works fine, but if I try to unbind the callback (just uncomment the line), it fails with the following

问题 I've got a blocking problem with the sorting functionality of a JTable; this made stall the development of the spare time open source project for 4 months now. Hope to be pointed into the right direction here. Context: I'm working on extending the functionality of the ps3mediaserver to add a media library with pms-mlx. The UI of the media server has been done using swing. Problem: When clicking on a column header in the JTable, a seemingly random column gets sorted instead of the one having