HI,
Am on creation of touch screen UI system.And am generating button for selecting products
Under certain category.
--> array of button creating dynamically And placing in TABPAGE when user selects Tab for category.
The button will be created with the name of products, Under the category selected.
{
'the way am creating controls.
mybutton(j) = new button()
mybutton(j).top = 100
}
How can i get the Click event of those buttons-( in the array)....??
You can use the += operator to assign a handler to an event, for example:
myButton.Click += ButtonClick;
and then declare it like this:
public void ButtonClick(object sender, EventArgs e)
{
// ...
}
Alternatively, if the code is short, you may like to specify it right there directly, for example:
myButton.Click += (sender, e) =>
{
// ...
}
The advantage of that latter method is that you can capture outside variables, such as for example the array of buttons and the index of this particular button.
Have a look at this link. http://forums.asp.net/p/1583639/3997438.aspx
Add button into the list and create a event for that.
Related
How can I toggle the checkbox of an item in a CheckedListbox if CheckOnClick is True, but SelectionMode is None..?
If I set SelectionMode to One it works as expected, but I would like to prevent items in the list from being selected. The only purpose of the CheckedListbox is to use the checkboxes; having items selected is not desired.
I tried a bit of code with the various Click and Mouse events, but none of them seem to report the item in the list that was clicked. If I could determine that, it would be a simple matter to toggle the checkbox of the clicked item.
The MouseClick event will tell you when the control was clicked and where. Determine whether the click was on an item and which one, then toggle it:
Private Sub CheckedListBox1_MouseClick(sender As Object, e As MouseEventArgs) Handles CheckedListBox1.MouseClick
Dim clickedIndex = CheckedListBox1.IndexFromPoint(e.X, e.Y)
If clickedIndex <> ListBox.NoMatches Then
CheckedListBox1.SetItemChecked(clickedIndex, Not CheckedListBox1.GetItemChecked(clickedIndex))
End If
End Sub
After a little testing, I would say that you need to consider “how” you want to achieve the non-selection mode you describe. As you have noted, if you set the CheckedListBoxes SelectionMode to None… then basically the check boxes become unusable.
The user cannot check or un-check any check box, as you already know… and this is why you want “your” code to change the check boxes checked state. So, you have now inherited the job of changing the check boxes check state because you set its “SelectionMode” to “None" … ? …
In addition, when the selection mode is set to “None” … then many “typical” properties of the CheckedListBox will lose functionality and become useless. Example, the checked list boxes SelectedItem property will always be null and its SelectedIndex property will most likely always be -1. Meaning, most “selection” type events will need to find what item was clicked by using the mouse location as shown in another answer.
The main point here is that when you decided to set the checked list boxes selection mode to “None”, then you basically open the door for more coding/responsibility on your part as far as “managing” the checked list box. I am just saying that the out-of-the-box .Net CheckedListBox is not feature rich and is a basic control. I am guessing there “may” be a third-party CheckedListBox Control that may have this “non-selected” functionality built-in.
So… I suggest another approach… however… it also has some drawbacks… basically you have to create a new Class MyCheckedListBox type “Control” that inherits from the CheckedListBox and then override its draw method to paint the cell the way we want.
I tend to avoid creating new controls. However, this will allow us to “keep” the CheckedListBoxes “selection functionality” by keeping its SelectionMode set to One. In addition to removing the job of “your” code having to manage each check box’s check state… we can also use all the checked list boxes “selection” events and use them as we typically would using the list boxes “selection” properties.
Below is a crude example of how to override the CheckedListBox’s Draw method to keep the “selected” items back color to the same color of the non-selected items.
class CheckedListBox_NoSelect : CheckedListBox {
protected override void OnDrawItem(DrawItemEventArgs e) {
DrawItemEventArgs new_e_Args = new DrawItemEventArgs
(e.Graphics,
e.Font,
new Rectangle(e.Bounds.Location, e.Bounds.Size),
e.Index,
(e.State & DrawItemState.Focus) == DrawItemState.Focus ? DrawItemState.Focus : DrawItemState.None,
this.ForeColor,
this.BackColor);
base.OnDrawItem(new_e_Args);
}
}
The code above is a simplified version of this SO question… How change the color of SelectedItem in CheckedListBox in WindowsForms? …
As I started, you will have to decide which approach you need. I may tend to go the route of #user18387401‘s answer … simply to avoid creating a new User Control. However, if you want this functionality for all the CheckedListBoxes, then creating the control may be a better approach.
Below is a full example of what is described above.
The CheckedListBox on the left is a regular CheckedListBox and uses the approach from user18387401‘s answer. The CheckedListBox on the right is our new control class CheckedListBox_NoSelect above.
For each control, the SelectedIndexChanged event is wired up to demonstrate that the checked list box on the left with its SelectionMode set to None will always have its SelectedItem set to null and its SelectedIndex will always be set to -1. However, it is not difficult to figure out “which” item was selected using user18387401‘s approach. This index is also displayed in its SelectedIndexChanged event.
private void Form1_Load(object sender, EventArgs e) {
checkedListBox1.SelectionMode = SelectionMode.None;
checkedListBox1.Items.Add("Item 1");
checkedListBox1.Items.Add("Item 2");
checkedListBox1.Items.Add("Item 3");
checkedListBox1.Items.Add("Item 4");
checkedListBox1.Items.Add("Item 5");
checkedListBox1.CheckOnClick = true;
// Leave default selection mode to "One"
checkedListBox_NoSelect1.Items.Add("Item 1");
checkedListBox_NoSelect1.Items.Add("Item 2");
checkedListBox_NoSelect1.Items.Add("Item 3");
checkedListBox_NoSelect1.Items.Add("Item 4");
checkedListBox_NoSelect1.Items.Add("Item 5");
checkedListBox_NoSelect1.CheckOnClick = true;
}
private void checkedListBox1_MouseClick(object sender, MouseEventArgs e) {
int clickedIndex = checkedListBox1.IndexFromPoint(e.X, e.Y);
if (clickedIndex != -1) {
checkedListBox1.SetItemChecked(clickedIndex, !checkedListBox1.GetItemChecked(clickedIndex));
Debug.WriteLine("LEFT: MouseClick Selected Index: " + clickedIndex);
}
}
private void checkedListBox1_SelectedIndexChanged(object sender, EventArgs e) {
Debug.WriteLine(" LEFT -> Item: " + (checkedListBox1.SelectedItem == null ? "Null" : checkedListBox1.SelectedItem));
Debug.WriteLine(" LEFT -> Index: " + checkedListBox1.SelectedIndex);
}
private void checkedListBox_NoSelect1_SelectedIndexChanged(object sender, EventArgs e) {
Debug.WriteLine("RIGHT -> Item: " + (checkedListBox_NoSelect1.SelectedItem == null ? "Null" : checkedListBox_NoSelect1.SelectedItem));
Debug.WriteLine("RIGHT -> Index: " + checkedListBox_NoSelect1.SelectedIndex);
}
I hope this makes sense and helps. Sorry that I did this in C#. If you can not convert the code to a VB version, then let me know and I will add a VB version.
I am using http://christian-helle.blogspot.in/2011/01/multi-platform-mobile-development_19.html for creating a custom list view.
In the existing sample it is not possible to pre set the selectedIndex of list view.
I have made few changes to the sample code and I am able to set the index and highlight it. but the problem is I am not able to set the scroll position to the highlighted item.
I have tried to set scrollBar.Value = itemindex, but it is not reflecting on the custom list view.
The simplest solution would be ListView.EnsureVisible.
private ListView listView1;
private void listView1_SelectedIndexChanged(object sender, EventArgs e)
{
if (-1 < listView1.SelectedIndex) {
listView1.EnsureVisible(listView1.SelectedIndex);
}
}
I am working on a Compact Framework application. This particular hardware implementation has a touchscreen, but its Soft Input Panel has buttons that are simply too small to be useful. There are more than one form where typed input is required, so I created a form with buttons laid out like a keypad. The forms that use this "keypad" form are modal dialogs. When a dialog requiring this "keypad" loads, I load the "keypad" form as modeless:
private void CardInputForm_Load(object sender, EventArgs e)
{
...
keypadForm = new KeypadForm();
keypadForm.Owner = this;
keypadForm.SetCallback(keyHandler);
keypadForm.Show();
}
The SetCallback method tells the "keypad" form where to send the keystrokes (as a Delegate).
The problem I'm having is that the modeless "keypad" form does not take input. It is displayed as I expect, but I get a beep when I press any of its buttons, and its caption is grayed-out. It seems like the modal dialog is blocking it.
I've read other posts on this forum that says modal dialogs can create & use modeless dialogs. Can anyone shed light on this situation? Is there a problem with my implementation?
I found the answer: Set the keypad form's Parent property, not its Owner property, to the form instance wanting the keystrokes. The keypad dialog's title bar stays grayed out, but the form is active.
private void CardInputForm_Load(object sender, EventArgs e)
{
// (do other work)
keypadForm = new KeypadForm();
keypadForm.Parent = this;
keypadForm.Top = 190; // set as appropriate
keypadForm.Show();
}
Be sure to clean up when done with the parent form. This can be in the parent's Closing or Closed events.
private void CardInputForm_Closing(object sender, CancelEventArgs e)
{
// (do other work)
keypadForm.Close();
keypadForm.Dispose();
}
There are two panels on the keypad form, one with numerals and one with letters and punctuation that I want. There is also an area not on a panel that is common to both, containing buttons for clear, backspace, enter/OK, and cancel. Each panel has a button to hide itself and unhide its counterpart ('ABC', '123', for example). I have all the buttons for input on the keypadForm fire a common event. All it does is send the button instance to the parent. The parent is responsible for determining what action or keystroke is desired. In my case I named the buttons "btnA", "btnB", "btn0", "btn1", "btnCancel", etc. For keystrokes, the parent form takes the last character of the name to determine what key is desired. This is a bit messy but it works. Any form wishing to use the keypad form inherits from a base class, defining a method for callback.
public partial class TimeClockBase : Form
{
public TimeClockBase()
{
InitializeComponent();
}
// (other implementation-specific base class functionality)
public virtual void KeyCallback(Button button)
{
}
}
The click event on the keypad form looks like this.
private void btnKey_Click(object sender, EventArgs e)
{
// play click sound if supported
(Parent as TimeClockBase).KeyCallback(sender as Button);
}
The method in the parent form looks like this.
public override void KeyCallback(Button button)
{
switch (button.Name)
{
case "btnCancel":
// setting result will cause form to close
DialogResult = DialogResult.Cancel;
break;
case "btnClear":
txtCardID.Text = string.Empty;
break;
// (handle other cases)
}
}
I have a bar graph and I want to allow the user to right click a particular bar, select some operation (add one or anything really) that will affect only that bar. Is this type of thing possible using ZedGraph?
You can add a Mouse Click event to the Form and call FindNearestObject() passing in that mouse point, you'll get back the nearest object. Something like this perhaps:
private void zedGraphControl2_MouseClick(object sender, MouseEventArgs e)
{
object nearestObject;
int index;
this.zedGraphControl2.GraphPane.FindNearestObject(new PointF(e.X, e.Y), this.CreateGraphics(), out nearestObject, out index);
if (nearestObject != null && nearestObject.GetType() == typeof(BarItem))
{
BarItem barItem = (BarItem)nearestObject;
barItem[index].Y += 1;
zedGraphControl2.Invalidate();
}
}
Say I have 3 forms , Form A , Form B , Form C.
I want Form B to be on top of Form A
and Form C to be on top of Form B.
how do I accomplish this ?
When you call ShowDialog pass the form that you want it to be in front of as a parameter to ShowDialog.
Use the Show(owner) overload to get form B on top of A. You'll need to set the size and location in the Load event so you can be sure it is exactly the right size even after scaling. And listen for the LocationChanged event so you can move the bottom form as well. This works well, other than a few interesting minimizing effects on Win7.
private void button1_Click(object sender, EventArgs e) {
var frmB = new Form2();
frmB.StartPosition = FormStartPosition.Manual;
frmB.Load += delegate {
frmB.Location = this.Location;
frmB.Size = this.Size;
};
frmB.LocationChanged += delegate {
this.Location = frmB.Location;
};
frmB.Show(this);
}