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Apply parent mouse events to child elements

I am making little Windows Forms Application.
I have PictureBox (parent) and Label (child) in it.
The Parent's Mouse Events are working perfectly, but Mouse events generated by child elements are not reflected on the Parent. The Cursor also changes back to its default (arrow).
Is it possible to pass events generated by child Controls, e.g., the MouseEnter event, to the Parent Control?
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
Card.MouseEnter += new EventHandler(Card_MouseEnter);
Card.MouseLeave += new EventHandler(Card_MouseLeave);
Card.MouseDown += new MouseEventHandler(this.Card_MouseDown);
Card.MouseUp += new MouseEventHandler(this.Card_MouseUp);
}
void Card_MouseLeave(object sender, EventArgs e)
{
this.Card.BackgroundImage = ((System.Drawing.Image)(Properties.Resources.card_bg));
this.Rename("Running!");
}
void Card_MouseEnter(object sender, EventArgs e)
{
this.Card.BackgroundImage = ((System.Drawing.Image)(Properties.Resources.card_hover_bg));
}
private void Card_MouseDown(object sender, EventArgs e)
{
this.Card.BackgroundImage = ((System.Drawing.Image)(Properties.Resources.card_click_bg));
}
private void Card_MouseUp(object sender, EventArgs e)
{
this.Card.BackgroundImage = ((System.Drawing.Image)(Properties.Resources.card_hover_bg));
this.Rename("Please Wait...");
}
private void CardName_MouseDown(object sender, MouseEventArgs e)
{
}
void Rename(string args)
{
this.CardName.Text = args;
}
private void CardName_Click(object sender, EventArgs e)
{
}
}
         
This is what I have This is what I want to achieve
The first animation represents what I have now, the second is what I need to achieve :)

When I'm making pictureBox1.Controls.Add(label1) label1 is
disappearing and I tried bring to front and change color but couldn't
do it. Please if you will have any idea show me in provided code by me
to be understandable for me. Thank you all again and again :)
You'd use code like this, maybe in the Load() event of the Form:
private void Form1_Load(object sender, EventArgs e)
{
Point pt = CardName.Parent.PointToScreen(CardName.Location);
Card.Controls.Add(CardName);
CardName.Location = Card.PointToClient(pt);
}
This keeps the label in the same position as it was, but makes the picturebox the parent.
Not sure where you're going wrong. Here's an example showing it in action. Both the PictureBox (Card) and Label (CardName) are inside a Panel (panel1). Clicking on button2 toggles the visibility of the Card. Clicking on button1 makes Card the Parent of CardName. You can see that at first, only the Card toggles visibility, but after clicking on button1 and setting the Parent, both toggle visibility together since CardName is a Child of Card (it also changes its BackColor to match that of its new Parent):
Code:
public partial class Form1 : Form
{
private void button1_Click(object sender, EventArgs e)
{
Point pt = CardName.Parent.PointToScreen(CardName.Location);
Card.Controls.Add(CardName);
CardName.Location = Card.PointToClient(pt);
}
private void button2_Click(object sender, EventArgs e)
{
Card.Visible = !Card.Visible;
}
}
When I move mouse over label, panel thinks mouse left it and rises
MouseLeave event
Here is how you can tell if the cursor has actually left the BOUNDS of the Panel, as opposed to simply enter a child control within the Panel:
private void panel1_MouseEnter(object sender, EventArgs e)
{
panel1.BackColor = Color.Red;
}
private void panel1_MouseLeave(object sender, EventArgs e)
{
Point pt = panel1.PointToClient(Cursor.Position);
if (!panel1.ClientRectangle.Contains(pt))
{
// we only get in here when the cursor leaves the BOUNDS of panel1
panel1.BackColor = Control.DefaultBackColor;
}
}

First of all, you should build a UserControl as a container for all your objects: it'd make everything simpler (the one I'm using here is actually a UserControl, modified to comply with your current setup).
When a Control other than the PictureBox is interacted with, you can decide whether you want to trigger a similar action on the main Control or perform a different action based on what event has been generated.
▶ When the Mouse Pointer enters you assembled Control, you want to change the default Cursor: then, when one of the Labels raises the Enter event, call the method of the main Control that handles this. An event handler is a method, you can call it.
▶ When a Label is clicked, you don't want to trigger the related action of the main Control: in this case, there's nothing to do, just handle this event and perform the required action.
▶ The Label should be child of the main Control. You're using a PictureBox, which is not a ContainerControl. You can add child controls to it anyway. You need to do this in code, since - as mentioned - the PictureBox is not designed to host Controls, thus you cannot drop one inside it: the Control you drop will be parented with the Container that hosts the PictureBox (your Form, here).
When you set the parent in code, you need to remember that the Location of the child control is relative to the old Parent, so you have to re-define it's position.
E.g: PictureBox.Bounds = (100, 100, 100, 200) / Label.Bounds = (100, 250, 100, 50)
When the PictureBox becomes Parent of your Label, the Label.Location is still (100, 250): so, now, it will be hidden, since it's outside the visible bounds of its new Parent. You have to reposition it in relation to the new host: its new Location should be (0, 150), to keep the previous relative position.
PictureBox.Control.Add(Label);
//[...]
Label.Location = new Point(Label.Left - PictureBox.Left, Label.Top - PictureBox.Top);
=> Label.Location = (100 - 100, 250 - 100) => (0, 150)
Or, centered horizontally:
Label.Location = new Point((PictureBox.Width - Label.Width) / 2, Label.Top - PictureBox.Top);
=> Label.Location = ((100 - 100) / 2, 250 - 100) => (0, 150) // <- Since both have the same Width
Or, using positions relative to the Screen:
var p = Label.PointToScreen(Point.Empty); // Relative to the ClientRectangle (Top/Left = (0, 0))
PictureBox.Controls.Add(Label);
Label.Location = PictureBox.PointToClient(p);
In any case, call BringToFront() after, to ensure that the new child Control is brought on top and anchor the Control, so it will keep its position and its Width will be bound to the Parent Width:
Label.BringToFront();
Label.Anchor = AnchorStyles.Left | AnchorStyles.Bottom | AnchorStyles.Right;
Now, assuming you want to change the Cursor to Cursors.Hand when the Mouse enters your combined Control and reset to default when it leaves it:
▶ You want the Cursor to change shape in any case.
▶ You want to generate different actions when the PictureBox is clicked and when one of the Labels is clicked.
▶ Both Labels can have distinct actions when clicked.
→ In the visual sample, the Label above the PictureBox is named lblTitle, the Label inside the PictureBox, at the bottom, is named lblFooter.
→ The PictureBox is named ImageView.
Setup the handlers:
NOTE: With a UserControl, the events handling, e.g., in relation to MouseEnter, changes in:
// The Parent's MouseEnter calls OnMouseEnter
protected override void OnMouseEnter(EventArgs e)
{
base.OnMouseEnter(e);
this.Cursor = Cursors.Hand;
}
// Child Controls just call the same method
private void Labels_MouseEnter(object sender, EventArgs e) => OnMouseEnter(e);
public Form1()
{
InitializeComponent();
Point p = lblFooter.PointToScreen(Point.Empty);
ImageView.Controls.Add(lblFooter);
lblFooter.Location = ImageView.PointToClient(p);
ImageView_MouseEnter += ImageView_MouseEnter;
ImageView_MouseLeave += ImageView_MouseLeave;
// Not added in the code here, do whatever is needed with this handler
ImageView_Click += ImageView_Click;
lblFooter.MouseEnter += Labels_MouseEnter;
lblFooter.MouseLeave += Labels_MouseLeave;
lblFooter.MouseClick += lblFooter_MouseClick;
lblTitle.MouseEnter += Labels_MouseEnter;
lblTitle.MouseLeave += Labels_MouseLeave;
lblTitle.MouseDown += lblTitle_MouseDown;
lblTitle.MouseUp += lblTitle_MouseUp;
}
private void ImageView_MouseEnter(object sender, EventArgs e) => this.Cursor = Cursors.Hand;
private void ImageView_MouseLeave(object sender, EventArgs e) => this.Cursor = Cursors.Default;
private void Labels_MouseEnter(object sender, EventArgs e)
{
ImageView_MouseEnter(ImageView, e);
// [...]
// Do stuff related to the Labels Enter event
}
private void Labels_MouseLeave(object sender, EventArgs e) {
ImageView_MouseLeave(ImageView, e);
}
private void lblTitle_MouseDown(object sender, MouseEventArgs e) {
// Perform actions when the Mouse button is held down lblTitle
}
private void lblTitle_MouseUp(object sender, MouseEventArgs e) {
// Perform actions when the Mouse button is released
}
private void lblFooter_MouseClick(object sender, MouseEventArgs e) {
// Perform actions on a Mouse Click event on lblFooter
}

Winforms custom cursor stops setting after a time

I have a form that contains a panel. The idea is that when the mouse is hovered over the panel it displays the OpenHand cursor. You can then drag the panel which causes the cursor to change to the Grab cursor. Upon mouse release the Grab cursor should change back to the OpenHand cursor.
Unfortunately, I'm having an issue that if I drag and release my panel (with the mouse within the bounds of the panel), eventually (usually on the second or third go) the Grab cursor will not change back into the OpenHand cursor.
This remains the case even when you move the mouse out of the panel and back in and try dragging and releasing.
Here is my Panel class:
public class MapPanel : Panel
{
private Point MouseDownLocation;
private Cursor OpenHand = new Cursor(Properties.Resources.hand.Handle);
private Cursor Grab = new Cursor(Properties.Resources.punch.Handle);
public MapPanel()
{
MouseDown += new MouseEventHandler(mapPanel_MouseDown);
MouseUp += new MouseEventHandler(mapPanel_MouseUp);
MouseMove += new MouseEventHandler(mapPanel_MouseMove);
}
private void mapPanel_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
Cursor = Grab;
MouseDownLocation = e.Location;
}
}
private void mapPanel_MouseUp(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
Cursor = OpenHand;
}
}
private void mapPanel_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
Left = e.X + Left - MouseDownLocation.X;
Top = e.Y + Top - MouseDownLocation.Y;
}
}
}
Interestingly there are no issues if I don't include the MouseMove handler, however the Cursor = OpenHand; statement inside the MouseUp method does still get called with the MouseMove handler included. It just doesn't take effect.
Hopefully someone can shed some light on this. Any help would be very much appreciated!

Redrawing issues when moving a control

I am trying to move some controls around on a WinForm with the mouse. I am using the code below. To see my issue start a new project in VS add the code below. Set the form BackGroundImage to any image then add any control. Set the control events for MouseUp, MouseDown, and MouseMove. Start debugging and click and move the control. The image in the form starts getting erased. I have tried several different suspend drawing classes and methods I have found on the net but nothing I have found lets me move the controls around without serious flickering or not being able to see the move. Any help would be appreciated.
P.S. If you set the same events to the up, move, and down events of the form, it moves fine with out any flickering.
private bool _mouseDown;
private Point _startPoint;
private void Event_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
_mouseDown = true;
_startPoint = new Point(e.X, e.Y);
}
}
private void Event_MouseUp(object sender, MouseEventArgs e)
{
_mouseDown = false;
}
private void Event_MouseMove(object sender, MouseEventArgs e)
{
if (_mouseDown)
{
Control s = sender as Control;
s.Location = new Point(e.X + s.Left - _startPoint.X, e.Y + s.Top - _startPoint.Y);
}
}

Prevent drag and drop outside of the current control (TreeNodes in a TreeView)

I'm maintaining a Windows app that has multiple forms in the one window (form1, form2, form3). I'm treating the other form2 and form3 as black boxes at the moment. In form1 I have a TreeView, and I'm implementing drag and drop functionality within that TreeView.
How can I prevent a drop outside of the form1 control?
I'm implementing 3 events handlers:
private void treeView_ItemDrag (...)
{
DoDragDrop(e.Item, DragDropEffects.Move);
}
private void treeView_DragEvent (...)
{
e.Effect = DragDropEffects.Move;
}
private void treeView_DragDrop (...)
{
//the node move logic here
}
form2 and form3 have a drag and drop relationship between them, so when I drag a node from form1 into form3 by default it allows the move (bad). I want to be able to prevent this from the form1 control code.
How can I prevent a drop outside of the form1 control? I've looked at the _DragLeave event, but I'm unsure how to control the operation without the DragEventArgs.

There is this little know property in the Cursor object that can restrict the mouse movement only to a certain rectangle.
this as a global variable for Form1
Rectangle _originalClip;
this goes in your Form1_Load event
_originalClip = Cursor.Clip;
this could be in your treeView.ItemDrag, forcing the cursor inside the form1 client area
Cursor.Clip = form1.RectangleToScreen(form1.ClientRectangle);
Now you need to restore the original clip area. A good place will be in the treeView.DragDrop. But to be on the safe side put also in your Form1_Closing event
Cursor.Clip = _originalClip;

You can check if mouse drag action is going outside the allowed area, and if so, cancel the drag action.
There's a nice sample in MSDN that uses the QueryContinueDrag event for that purpose. I think you can use that on the base of your solution.
Link: DragAction Enumeration

I know this is an old topic, but since I've never found a good answer to how to prevent dragging a control outside of a panel, I thought that I'd throw in the solution that I put together. I used some the tips from above and some work of my own.
private void Form1_Load(object sender, EventArgs e)
{
_originalClip = Cursor.Clip;
}
private void pb_MouseMove(object sender, MouseEventArgs e)
{
PictureBox pb = (PictureBox)sender;
if (e.Button == MouseButtons.Left)
{
Size sz = new Size(panel1.RectangleToScreen(panel1.ClientRectangle).Width - (pb.Width), panel1.RectangleToScreen(panel1.ClientRectangle).Height - (pb.Height));
Point loc = new Point(panel1.RectangleToScreen(panel1.ClientRectangle).X + (pb.Width / 2), panel1.RectangleToScreen(panel1.ClientRectangle).Y + (pb.Height / 2));
Rectangle rct = new Rectangle(loc, sz);
Cursor.Clip = rct;
pb.Left += (e.X - x);
pb.Top += (e.Y - y);
}
}
private void pb_MouseUp(object sender, MouseEventArgs e)
{
Cursor.Clip = _originalClip;
}
What this does is uses the Cursor.Clip method along with a Rectangle object with it's size set to be the size of the panel ("panel1" in the code) containing a bunch of Pictureboxes ("pb" in the code). The new rectangle's size is set to the parent panel minus the width and height of the Picturebox and it's location set to the location of panel1 minus half of the Picturebox's width and height. This gives you a rectangle which will constrain the Picturebox from being drug outside the panel.

.NET C# MouseEnter listener on a Control WITH Scrollbar

As long as the mouse is over a specific control, we show some form. When the mouse leaves the control, we hide the control after a small timeout. This is standard hover behavior.
However, when a control (for example a Treeview) has a scrollbar, and the mouse is ON or OVER the scrollbar, the events don't fire ...
If we could get a reference to the scrollbar control, this would solve our problem, as we would add the same listener events to the scrollbar. However, the scrollbar isn't accessible as far as I know ...
How can we solve this problem ?

The scrollbar is in the tree view's non-client area. When the mouse moves there, it starts generating non-client messages like WM_NCMOUSEMOVE and WM_NCMOUSELEAVE. You would have to sub-class the TreeView and override WndProc() to detect these message.
This doesn't really solve your problem though, you'll still have a hard time with edge cases. A low-tech approach with a Timer always works:
private Form frmPopup;
private void treeView1_MouseEnter(object sender, EventArgs e) {
timer1.Enabled = true;
if (frmPopup == null) {
frmPopup = new Form2();
frmPopup.StartPosition = FormStartPosition.Manual;
frmPopup.Location = PointToScreen(new Point(treeView1.Right + 20, treeView1.Top));
frmPopup.FormClosed += (o, ea) => frmPopup = null;
frmPopup.Show();
}
}
private void timer1_Tick(object sender, EventArgs e) {
Rectangle rc = treeView1.RectangleToScreen(new Rectangle(0, 0, treeView1.Width, treeView1.Height));
if (!rc.Contains(Control.MousePosition)) {
timer1.Enabled = false;
if (frmPopup != null) frmPopup.Close();
}
}

I think there are several different ways to do this, but the key is your desire to have a timeout on the action. I think a combination of two techniques might work:
Put the control on a panel, docked to fill, and use the MouseEnter of the panel to turn on your behavior -- this will include the control's scrollbar. You can use the MouseLeave event of the panel as well, but you'll have to check the cursor's position to ensure it hasn't moved into the contained control. This method is mostly reliable, but moving the mouse quickly can confuse it.
If you combine this with a timer that starts when your shown/hidden control is shown and check the cursor position periodically. This will work, but your timeout before hiding the control won't necessarily be consistent (because the timer starts when they enter the control). You could stop/start the timer on mousemoves in the control to alleviate this somewhat.
I put together a project of the different methods I tried here: http://lovethedot.s3.amazonaws.com/100609StackoverflowScrollbarQuestion.zip
By docking the control you want to track in the panel, it essentially wraps it and you'll get MouseEnter at the very edge of the tracked control:
private void panel1_MouseEnter(object sender, EventArgs e)
{
this.Text = "in";
}
private void panel1_MouseLeave(object sender, EventArgs e)
{
if (!new Rectangle(new Point(0, 0), panel1.Size).Contains(panel1.PointToClient(Control.MousePosition)))
this.Text = "out";
}
You're tracking entry into the panel surrounding the control, and exit from that panel provided the cursor isn't inside the tracked control.
To get a better "leave" experience, it's combined with a Timer that checks to see where the cursor is as well:
private void listBox3_MouseEnter(object sender, EventArgs e)
{
button1.Visible = true;
visibleTimer.Stop();
visibleTimer.Start();
}
void visibleTimer_Tick(object sender, EventArgs e)
{
if (!new Rectangle(new Point(0, 0), listBox3.Size).Contains(listBox3.PointToClient(Control.MousePosition)))
{
visibleTimer.Stop();
button1.Visible = false;
}
}