After GTK.ComboBox open GTK dialog hangs - c

We use GTK library for UI.
I have simple dialog box with ComboBox inside.
When I open ComboBox, choose something and close it. Dialog hangs and keyboard navigation 'Tab' doesn't work.
GTK 2.12.6 is used.
ComboBox glade layout
Simple text combo box is created in this way.
dialog_uidpwd_combobox_domain = gtk_combo_box_new_text ();
gtk_widget_show (dialog_uidpwd_combobox_domain);
gtk_table_attach (GTK_TABLE (table3), dialog_uidpwd_combobox_domain, 1, 2, 2, 3,
(GtkAttachOptions) (GTK_FILL),
(GtkAttachOptions) (GTK_FILL), 0, 0);
And later it is initialised with elements:
i = 0;
while (domain_list && domain_list[i])
{
gtk_combo_box_append_text(GTK_COMBO_BOX(combobox),domain_list[i]);
free(domain_list[i]);
i++;
}
gtk_combo_box_append_text(GTK_COMBO_BOX(combobox), "test 1");
gtk_combo_box_append_text(GTK_COMBO_BOX(combobox), "test 2");
if (i > 0)
{
gtk_combo_box_set_active(GTK_COMBO_BOX(combobox), index_default);
}
How can I fix dialog freeze after ComboBox close?
UPDATE!
Event when I try to handle ComboBox change event and to set focus to another control.
It succeeds to focus another control, but dialog stays in freeze. And keyboard navigation with "Tab" doesn't work and even focused in "Change" event handler "Password" field doesn't catch key input.
On first picture here is "change" event handler.
On second another control focused after "change" event handler work.
Looks like ComboBox maybe is destroyed in a bad way and all input continues to go there. I don't know, but dialog ignores key handling.

Related

Handling/capturing a button click event as a priority in WinForms

This is the mock-up of a child window that I have in a Windows Forms application.
This will be shown when a button is clicked on the parent window.
When the child form opens up, the focus is in Text box1.
The Leave event on the Text box1 fires when the user tabs out of it or clicks on any button.
This triggers a validation:
if(String.IsNullOrEmpty(textBox1.Text)
{
MessageBox.Show("Please enter a value of Id.");
}
else {
... other logic omitted for brevity
}
Now the user can also click on the Cancel button to exit the form without doing any action.
Here, on the first try, the Leave event fires because the focus is in Text box1 when the Form is loaded so when the user clicks on Cancel for the first time the form does not close, instead the message box with validation message is shown.
On the second click, since the focus is no longer on Text box1, the Leave event does not fire and the form closes.
I can put the focus on any other control to handle this but for the sake of user experience I had to put the focus on Textbox1 since it's value decides the further logic of what is shown in Textbox2(Textbox1 can be left empty in which case nothing is shown in Textbox2 but that is not related to this question).
Tried this to see if I can get the Cancel button inside the Leave event of Textbox1:
Button b = sender as Button
b is NULL when Cancel is clicked.
What can I do to make the Cancel click work, without triggering the Leave event initially?
Thanks in advance,
Regards.
If you only want to supress the error message when the cancel button recieves the focus, simply check for the cancelButton.Focused flag in the leave event, then block the message if the cancel button got the focus.
Nevertheless, it is usually considered good practice to avoid modal dialog boxes if they are not required. So depending on your particular situation, you may decide to replace the MessageBox with a ToolTip instead, which will not entirely block the UI thread.

How to know if the AutoComplete listbox on an TextBox is open?

I have a form with 2 textboxes. The first one has a customsource for its autocompletion set like this :
textBox1.AutoCompleteMode = AutoCompleteMode.SuggestAppend;
textBox1.AutoCompleteSource = AutoCompleteSource.CustomSource;
textBox1.AutoCompleteCustomSource = GetUserNames();
The GetUserNames() method retuns an AutoCompleteCustomSource and all this works very well.
When this form opens the focus in on the first textbox, the user can type in or choose from the autocomplete and that works well.
Both textboxes have an onKeyDown event and in that event they should do some validations using the values of both textboxes.
I want to keydown to only do its validations when ENTER is pressed when the autocomplete listbox is closed.
Look at it this way:
the user starts typing, a list appears, the user chooses an item from the list and presses enter to confirm his choice, and then he wants to press TAB to go to the next textbox.
But when he presses ENTER after choosing an item in the autocomplete list the keyDown event already fires. At this stage the keydown event should not fire, the ENTER should only confirm the choice from the autocomplete list.
Is there a way to detect in the keydown that ENTER was pressed while the autocomplete list was still open ?
Or is there a way to disable the keydown event while the autocomplete list is open ?
EDIT:
from the comments I tried the answer in this link https://stackoverflow.com/a/40915048/3110834
Unfortunate it does not works in this case but it has teached me that pressing enter on the autocomplete suggestion does 2 things:
close the autocomplete window
fire the keydown event of the textbox
So I need to find a way to stop the keydown event for the textbox to fire when pressing enter on the autocomplete window.
Edit:
Things are far worse than I thought.
When you open the autosuggest box and then click on a suggested item to select it, the keydown event also fires and it has Keys.Enter in its KeyCode ! Since when is a click equal to a keystroke ?
How do I stop this ? Is this a bug ?
I ran into this same problem, I followed the approach in this link https://stackoverflow.com/a/40915048/3110834
if you try to evaluate if there is a list open during the Keydown event, it will always return a false, since the event already closed the list.
instead I observe the PreviewKeyDown event to evaluate if the AutoComplete list is open or not, if it is Open, i unsubscribe from the KeyDown event (which only uses the Enter key on my case) and if the list is close, i re-subscribe to it back again
private void tbxAND_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
if (IsAutoCompleteOpen())
{
tbxAND.KeyDown -= tbxAND_KeyDown;
}
else
{
tbxAND.KeyDown += tbxAND_KeyDown;
}
}
}
notice that IsAutoCompleteOpen() starts the code to enumerate the openlist.
this may not be the full solution for this particular case if you still need to catch other keys, but i wanted to leave the hint in case someone else run into this problem.

WPF window and element focus

I've got a WPF form inside a window and a short series of events like this:
1) 1st form has series of selection buttons
2) Clicking a button brings up a progress bar window over the existing window
3) Progress window closes and 1st form switches to a new 2nd form using page navigation
The problem is that the 2nd form (and the entire window) no longer has any focus and what's really killing me is that the window is no longer getting OnKeyDown() calls (it's still the top winow). If I hit the tab key the first menu option is highlighted and the following key stroke will fire a OnKeyDown(). Also, if I alt-tab to another app and then alt-tab back to my window it will begin receiving OnKeyDown() again.
How do I figure out where the focus is after the dialog?
If you are using navigation then the focus will have switched to the Page that you have navigated to, assuming that it is Focusable.
You can check that by setting up a breakpoint in a Focused event handle for the Page.
Alternatively you can use an explicit control.SetFocus() in the page.Navigated handler.

Control.Leave Triggered by MouseDown, not MouseUp

I have a C# .NET WinForm. In the form, I allow a user to add an item to a ListView by double-clicking in the ListView. This adds a TextBox control to the ListView and places the key cursor in the TextBox so a user can type.
I detect that a user is done with an item in a couple of ways (e.g. pressing Enter, Esc, Tab...), but also when they Leave (TextBox.Leave) the TextBox.
The problem is this set of steps:
User triggers TextBox.Leave by mousing down outside of the TextBox.
I add the new item to the ListView.
I select the the new item in the ListView.
Mouse up occurs and the new item that I just selected, loses focus and is unselected.
What I would like is for TextBox.Leave to be triggered by MouseUp, not MouseDown. How can I accomplish this?
Edit: Cody suggests using the ListView.LabelEdit property. Here are my results trying that:
listView_DoubleClick(...) {
listView.LabelEdit = true;
if(double clicked on existing listViewItem) {
listViewItem.BeginEdit(); //this works as expected
} else {
var newItem = listView.Items.Add("");
newItem.BeginEdit(); //this doesn't work, see below
}
}
The call to newItem.BeginEdit() only works when the user double clicks where the new item will show up. If they double click on any other blank area in the listview the new item is added, but it does not enter edit mode. What's going on here?
Pressing the mouse down on another control is causing that other control to request the focus and so the focus moving causes the TextBox.Leave event to occur. Preventing ever other possible control from requesting the focus is not a very viable option. But luckly you only need to prevent the ListView from using the MouseDown to shift focus. So you need to override the WndProc of your ListView and when the MouseDown windows message occurs and you are currently showing a TextBox you eat the message. In order words you do not allow the base class to process it.

Popup window and context menu

I am using the ToolStripDropDown to host the user control as the pop-up window. The problem is when a context menu strip is displayed from within this pop-up window, the pop-up itself closes in the moment the context menu opens.
I have tried to subclass the ContextMenuStrip and added WS_EX_NOACTIVATE to CreateParams but nothing changed. First I thought that there is no way to do this since it is common behavior but then I tried to put a TextBox class onto the pop-up user control and invoke the Edit control context menu - and the parent pop-up window did not close.
What am I missing?
Had a similary Problem. On my UserControll was a toolstrip. When I pressed the toolsstripdropdownbutton the dropdown was shown but the popup disapeared.
The reason was that popup.Autoclose was true. After Setting to false the Popup is not closed any more.
ToolStripDropDown popup = new ToolStripDropDown();
popup.AutoClose = false; //Set to FALSE
popup.Margin = Padding.Empty;
popup.Padding = Padding.Empty;
ToolStripControlHost host = new ToolStripControlHost(userControl1);
host.Margin = Padding.Empty;
host.Padding = Padding.Empty;
popup.Items.Add(host);
popup.Show(button1, new Point(100,100));
Actual Solution should be the one in Martin's final comment:
Use ContextMenu Instead of ContextMenuStrip
That one worked for me, and the ToolStripDropDown no longer closes by itself when right clicking one of its content controls, like it should. We still need it to AutoClose, disabling AutoClose on ToolStripDropDown will do bad things, it is supposed to close on losing focus. Example: open any other app window, and the ToolStripDropDown will continue to appear on top

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