Check if a control is on top of another - c#

I've been trying to make a drag and drop game. I have 4 panels and 4 labels. You have to drag the labels on top of the correct panel.
The problem is checking if a label is on top of the panel. The user can frely drag the labels.
private void button1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
button1.Left = e.X + button1.Left - MouseDownLocation.X;
button1.Top = e.Y + button1.Top - MouseDownLocation.Y;
}
}
private void button1_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
MouseDownLocation = e.Location;
}
}
Here is the code i used to move the control. I have to mention that this is a test project, so I used a button instead of a label, but the idea is the same.
Is there any way if I can check whether a control is on top of another or not ?

After each move, simply get the Rectangle from the Bounds property of your button and panel, then use either Intersect() or Contains():
private void button1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
button1.Location = new Point(e.X + button1.Left - MouseDownLocation.X, e.Y + button1.Top - MouseDownLocation.Y);
Rectangle btnRC = button1.Bounds;
Rectangle pnlRC = panel1.Bounds;
// see if the rectangles INTERSECT
if (pnlRC.IntersectsWith(btnRC))
{
panel1.BackColor = Color.Green;
}
else
{
panel1.BackColor = this.BackColor;
}
// see if the panel COMPLETELY CONTAINS the button
if (pnlRC.Contains(btnRC))
{
panel1.BackColor = Color.Green;
}
else
{
panel1.BackColor = this.BackColor;
}
}
}

To check if the mouse is over the control, you can check if the Cursor.Position is in the ClientRectangle of the control, but you first need to call PointToClient method of the control to convert the cursor position relative to the panel's (0,0), for example:
var b = panel1.ClientRectangle.Contains(panel1.PointToClient(Cursor.Position));
The flag can be checked in the same event handler which is used to move the control, for example:
if(b) panel1.BackColor = Color.Red; else panel1.BackColor = Color.Gray;

Related

how make label move inside panel bounds

i tried this code but when i drag and move label inside panel is normal but when i drag to edge bound of panel it disappear i want it to stop on panel bound is there a way for that?
private void lbl29_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
MouseDownLocation = e.Location;
}
panel1.Invalidate();
}
private void lbl29_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
lbl29.Left = e.X + lbl29.Left - MouseDownLocation.X;
lbl29.Top = e.Y + lbl29.Top - MouseDownLocation.Y;
}
}
You can try these:
Controls.SetChildIndex(lbl29, 0); or
Controls.SetChildIndex(panel1, 1); or
lbl29.BringToFront(); or
panel1.SendToBack();
But Controls.SetChildIndex(lbl29, 0); and Controls.SetChildIndex(panel1, 1); are more useful.

Moving control in runtime

I'm with a problem moving a label on a panel. When I move this label, reached the top and left (0.0), the label respects the top and left. To spend half of the screen, the label exceeds the panel as shown in picture.
My codes:
public partial class frmStandard : Form
{
Point startposition;
}
public void MouseDown(object sender, MouseEventArgs e)
{
startposition = e.Location;
}
public void MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
((Label)sender).Left = Math.Max(0, e.X + ((Label)sender).Left - startposition.X);
((Label)sender).Top = Math.Max(0, e.Y + ((Label)sender).Top - startposition.Y);
}
}
I need the label does not exceed the panel size.What should be added in the codes?
You need to check the other Borders.
You will have to use the dimension data of the containing Panel for this.
In the spirit of keeping things dynamic, as your code already is, I use he Label's Parent instead of referring to just the one Panel:
private void MouseMove(object sender, MouseEventArgs e)
{
Label L = (Label)sender;
Rectangle PR = L.Parent.ClientRectangle;
if (e.Button == MouseButtons.Left)
{
L.Left = Math.Min(Math.Max(0, e.X + L.Left - startposition.X), PR.Right - L.Width);
L.Top = Math.Min( Math.Max(0, e.Y + L.Top - startposition.Y), PR.Bottom - L.Height);
}
}
To keep it even more general, one could replace Label with Control and let the user move other Controls around wit the same pieces of code..

Separating mouse down and mouse click events

I have two events wired to a control. A mouse click event plays an audio file. A drag event made up from mouse down, mouse move and mouse up drags the control vertically. By dragging the control vertically the control get assigned a different song.
The problem I have is that when I drag the control the music plays. I do not want this since this is a dragging operation.
Music should play only when control is clicked and note moved.
I think that setting boundaries, e.g. when control moves only 5 pixels play sound otherwise drag control should solve the problem but I tried to create them unsuccessfully.
Can you please guide how to solve this problem preferably with code snippets.
Thank You.
The Drag
int Locked_yLoc; int index;
private void StartDrag(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
sp1.SoundLocation = this.pitch + ".wav";
sp1.Play();
tm1.Interval = 100 * this.noteDuration;
tm1.Start();
isDragging = true;
pitch = e.Y;
this.Location = new Point(this.Location.X, pitch);
}
}
private void StopDrag(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
isDragging = false;
this.Location = new Point(this.Location.X, Locked_yLoc);
pitch = index;
//lbl8.Text = pitch.ToString();
}
}
private void OnDrag(object sender, MouseEventArgs e)
{
if (isDragging)
{
this.Top = this.Top + (e.Y - pitch);
Locked_yLoc = (int)Math.Round((this.Top + (e.Y - pitch)) / 10.0) * 10;
for (int i = 0; i < yLocation.Length; i++)
{
if (Locked_yLoc == yLocation[i])
{
index = CorrPitch[i];
}
}
}
}
The Click
private void MusicNote_MouseClick(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
sp1.SoundLocation = this.pitch + ".wav";
sp1.Play();
tm1.Interval = 100 * this.noteDuration;
tm1.Start();
}
}

MouseMove doesn't get the right coordinate points

I have a label I am trying to drag. I click on the label, and on the MouseMove() event I am trying to relocate the position of the label.
public void MyLabel_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
((Label)sender).Location = Cursor.Position;
// I have also tried e.Location but none of these moves the label to
// where the the cursor is, always around it, sometimes completely off
}
}
You usually need to store the offset location of the initial mouse down point in the control, or else the control will move on you in a jittering fashion. Then you just do the math:
Point labelOffset = Point.Empty;
void MyLabel_MouseDown(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
labelOffset = e.Location;
}
}
void MyLabel_MouseMove(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
Label l = sender as Label;
l.Location = new Point(l.Left + e.X - labelOffset.X,
l.Top + e.Y - labelOffset.Y);
}
}

DataGridView Drag/Drop - limit to side 'bar' rather than cells

I have a DataGridView, where I allow users to Drag/Drop rows to reorder them. This works fine, but it seems to be very sensitive - just clicking and moving the mouse slightly when clicking a cell starts the drag/drop operation.
So what I want to do is only allow dragging and dropping from the 'side bar' of the DataGridView - i.e. the 'column' to the left of the red line in the below image:
Is this possible? Here is my code:
[code]
private Rectangle dragBoxFromMouseDown;
private int rowIndexFromMouseDown;
private int rowIndexOfItemUnderMouseToDrop;
private void grdCons_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
{
if (dragBoxFromMouseDown != Rectangle.Empty && !dragBoxFromMouseDown.Contains(e.X, e.Y))
{
DragDropEffects dropEffect = grdCons.DoDragDrop(grdCons.Rows[rowIndexFromMouseDown], DragDropEffects.Move);
}
}
}
private void grdCons_MouseDown(object sender, MouseEventArgs e)
{
rowIndexFromMouseDown = grdCons.HitTest(e.X, e.Y).RowIndex;
if (rowIndexFromMouseDown != -1)
{
Size dragSize = SystemInformation.DragSize;
dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2), e.Y - (dragSize.Height / 2)), dragSize);
}
else
{
dragBoxFromMouseDown = Rectangle.Empty;
}
}
private void grdCons_DragOver(object sender, DragEventArgs e)
{
e.Effect = DragDropEffects.Move;
}
private void grdCons_DragDrop(object sender, DragEventArgs e)
{
Point clientPoint = grdCons.PointToClient(new Point(e.X, e.Y));
rowIndexOfItemUnderMouseToDrop = grdCons.HitTest(clientPoint.X, clientPoint.Y).RowIndex;
if (e.Effect == DragDropEffects.Move)
{
DataGridViewRow rowToMove = e.Data.GetData(typeof(DataGridViewRow)) as DataGridViewRow;
grdCons.Rows.RemoveAt(rowIndexFromMouseDown);
grdCons.Rows.Insert(rowIndexOfItemUnderMouseToDrop, rowToMove);
}
}
[/code]
I managed to get Drag-and-Drop using only row headers working by checking the DataGridViewHitTestType in the MouseDown event handler like so:
private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
{
// Get the index of the item the mouse is below.
rowIndexFromMouseDown = dataGridView1.HitTest(e.X, e.Y).RowIndex;
// Here we also check that the HitTest happened on a RowHeader
if (rowIndexFromMouseDown != -1 && (dataGridView1.HitTest(e.X, e.Y).Type == DataGridViewHitTestType.RowHeader))
{
// Remember the point where the mouse down occurred.
// The DragSize indicates the size that the mouse can move
// before a drag event should be started.
Size dragSize = SystemInformation.DragSize;
// Create a rectangle using the DragSize, with the mouse position being
// at the center of the rectangle.
dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2),
e.Y - (dragSize.Height / 2)),
dragSize);
}
else
// Reset the rectangle if the mouse is not over an item in the ListBox.
dragBoxFromMouseDown = Rectangle.Empty;
}
I'm guessing that you got your code from the DataGridView FAQ since the code you have is almost identical to the example there?
If you didn't then I'd recommend having a look at the FAQ - it is filled with lots of good advice and examples.

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