I have code that lets be drag around a borderless form in winforms that I've been using for several months now, which works extremely well.
But when I first was given the code, they used this.Invalidate(); in the MouseMove event of the Form, and the Form flickered a little and was slow when dragging around. So, I replaced Invalidate() with Update() in the MouseMove event and, to my surprise, the Form can now be dragged very smoothly and has no flickering whatsoever.
Can somebody explain to me why Update makes the code work better than Invalidate, even when Invalidate sounds like it's the right one to be using?
Thanks :)
P.S. Maybe it would help more if I added the code... Adding it now.
Edit - Here's the code:
private void titlebar_MouseDown(object sender, MouseEventArgs e)
{
this.IsMouseDown = true;
this.LastCursorPosition = new Point(e.X, e.Y);
if (this.BackColor == Color.White)
{
this.BackColor = Color.GhostWhite;
tbox.BackColor = Color.GhostWhite;
tbox.ForeColor = Color.Black;
}
else
{
this.BackColor = Color.FromArgb(20, 20, 20);
tbox.BackColor = Color.FromArgb(20, 20, 20);
tbox.ForeColor = Color.White;
}
}
private void titlebar_MouseMove(object sender, MouseEventArgs e)
{
if (this.IsMouseDown == true)
{
//Move the form
this.Location = new Point(this.Left - (this.LastCursorPosition.X - e.X), this.Top - (this.LastCursorPosition.Y - e.Y));
// Update works better than Invalidate();.
Update();
}
}
private void titlebar_MouseUp(object sender, MouseEventArgs e)
{
this.IsMouseDown = false;
this.BackColor = fc;
tbox.BackColor = fc;
}
Invalidate() simply adds a region to the update region of the control. The next time WM_PAINT is received, the area you invalidated plus any other invalidated regions, are marked for painting. When RedrawWindow() is called, that will normally post a WM_PAINT message to the application queue. The system is free to do what it wants with that, usually more pressing business, and paint when it can.
If you call Update(), you get GDI+'s UpdateWindow() which won't mark a region for repainting, but pushes a WM_PAINT directly to WNDPROC(), bypassing the application queue.
If you need an immediate refresh of a control, use Refresh(), which invalidates the region then immediately calls Update().
Invalidate marks the window as needing to be refreshed (at some point). Update does it there and then if I remember correctly
Here is a link to explain the difference better than I'd be able to
Related
I think that must be only a little problem, but I can't get a clear thought on that. Someone an idea?
I have some borders on a canvas (filled with images) and i want to click the border (i do this with the OnMouseLeftButtonDown) where the border gets red (so the user knows for sure which object he had clicked) and then, after 1 or 2 seconds, when the mousebutton is still pushed down, a drag'n'drop should start.
At first I had the borders inside buttons, but the clickevent seems to conflict with the dragevent. So I got rid of the buttons and did everything inside the borders directly, which works well also. But how can I start the drag after the mousebuttondown and stop it when the mousebuttonup happens before the time runs out.
Someone an idea for a clean solution?
private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
_source = sender as Border;
Mouse.Capture(_source);
}
private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
_source = null;
Mouse.Capture(null);
}
and in event OnMouseMove you can modify border margins depends on mouse position but after checking if _source is type of Border.
var position = e.GetPosition(Canvas);
EDIT:
For that time you can add property Stopwatch _watch, and inside OnMouseLeftButtonDown event handler you can do it:
_watch = Stopwatch.StartNew();
in OnMouseLeftButtonUp:
_watch.Stop();
and in OnMouseMove before your code:
while (_watch.ElapsedMilliseconds < 2000 && _watch.IsRunning)
{
Thread.Sleep(100);
}
So i searched a little around on google to find some code to drag buttons with the mouse. I found a lot, even though none of these actually worked for me.
So i'm asking you! :-)
The code i'm trying to get working in my form:
bool isDragged = false;
Point ptOffset;
private void button1_MouseDown( object sender, MouseEventArgs e )
{
if ( e.Button == MouseButtons.Left )
{
isDragged = true;
Point ptStartPosition = button1.PointToScreen(new Point(e.X, e.Y));
ptOffset = new Point();
ptOffset.X = button1.Location.X - ptStartPosition.X;
ptOffset.Y = button1.Location.Y - ptStartPosition.Y;
}
else
{
isDragged = false;
}
}
private void button1_MouseMove( object sender, MouseEventArgs e )
{
if ( isDragged )
{
Point newPoint = button1.PointToScreen(new Point(e.X, e.Y));
newPoint.Offset(ptOffset);
button1.Location = newPoint;
}
}
private void button1_MouseUp( object sender, MouseEventArgs e )
{
isDragged = false;
}
I of course changed the pictureBox1 to button1.
But i just can't get this to work.
Anyone who might know why?
Oh, and i want to use this at all my buttons, so what should i replace button1 with to make it work at all of the buttons?
-Btw, i use Visual studio Express.
Thank you in advance!
even though i'm really just copy pasting when it comes to windows
forms
The code you posted won't actually do anything by itself!
To work, the MouseDown() and MouseMove() events of the control have to be wired up to those methods:
Select the control on the form (pictureBox1).
In the Properties Pane (bottom right by default), click the
"Lightning Bolt" icon to get a list of the events for that control.
Find the MouseDown entry and change the dropdown to the right of
it to pictureBox1_MouseDown.
Find the MouseMove entry and change the dropdown to the right of
it to pictureBox1_MouseMove.
Now run it and drag the pictureBox1 around.
EDIT: Here is how to make the code work for multiple controls, as outlined in my comment below.
bool isDragged = false;
Point ptOffset;
private void button1_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
isDragged = true;
Button btn = (Button)sender;
ptOffset = new Point(btn.Location.X - Cursor.Position.X, btn.Location.Y - Cursor.Position.Y);
}
else
{
isDragged = false;
}
}
private void button1_MouseMove(object sender, MouseEventArgs e)
{
if (isDragged)
{
Point newPoint = Cursor.Position;
newPoint.Offset(ptOffset);
Button btn = (Button)sender;
btn.Location = newPoint;
}
}
private void button1_MouseUp(object sender, MouseEventArgs e)
{
isDragged = false;
}
Ok, the good news: hopefully we'll have a CSI desktop layout once you're done.
The not so good news: I think you're trying to do the wrong thing.
I'm assuming you're using WinForms, but the idea should be the same for WPF.
When you run your program, the layout is set (either dynamically, for example it changes when you resize the window, or statically, for example when you set it with absolute X,Y position).
What you want to do is kind of: I want to get the benefits of them creating all the boiler plate code, but then, I want to dynamically change it at run time ...
I think you need to rethink your approach, and take this one step at a time (after all, it took Microsoft years to get the GUI to where it's at at the moment ... It'll take some time to get the cool futuristic GUI's out).
Take baby steps, but keep in mind the big picture:
Start with having a Canvas defined.
Then you can place a button on it.
Then fool around with moving that button on the canvas. (The code you have in your question should work for an object on a canvas).
From there, keep taking steps that will get you closer to your destination ...
I registered Hotkey: Ctrl + Space. Hotkey message is sent to:
private void Hotkey_press()
{
... // I want to show tooltip "Hello" at current mouse location.
}
Is there any way to show this tooltip even the mouse doesnt point to any control and it is outside my Window.Form1?
Edit: That ToolTip can show even the form lost focus or hide
You want something like
ToolTip tt = new ToolTip();
IWin32Window win = this;
tt.Show("String", win, mousePosition);
Where the MousePosition can be obtained from the MouseEventArgs via
private SomeMouseEventHandler(object sender, MouseEventArgs e)
{
System.Drawing.Point mousePosition = e.Location;
...
}
or using
System.Drawing.Point mousePosition = Cursor.Position;
also, you may want to set a longer duration for which the ToolTip is displayed, well just use the overloads available for the Show method, tt.Show("String", win, mousePosition, 5000); will display the tool tip for 5 seconds.
I hope this helps.
Tooltip tip = new ToolTip();
tip.ShowAlways = true;
tip.Show("My tooltip",this,Cursor.Position.X,Cursor.Position.Y);
http://msdn.microsoft.com/en-us/library/system.windows.forms.tooltip.aspx
http://msdn.microsoft.com/en-us/library/system.windows.forms.tooltip.showalways.aspx
http://msdn.microsoft.com/en-us/library/system.windows.forms.cursor.aspx
As this answer suggests, there is no managed way to accomplish this. If you want to show a tool tip control when your program is not in focus then the "right" way to do it is to PInvoke Win32 and use CreateWindowEx. The answer linked above given by gideon shows some pointers on how to do it, but nonetheless it is very complicated.
If you don't mind using thrid party libraries, AutoIt provides a way to create tool tips easily without having to deal with Win32 yourself.
Here is a very simple example demonstrating use:
//make sure AutoItX3.dll is referenced in your project
using AutoItX3Lib;
private AutoItX3 myAutoIt = new AutoItX3();
private async void ShowToolTipAtMouse(string message)
{
//default position is bottom right of mouse pointer,
//but you can set the x and y positions yourself
myAutoIt.ToolTip(message);
//call the function again with an empty argument to close
await Task.Delay(1000);
myAutoIt.ToolTip(String.Empty);
}
This will work as long as your program is running; doesn't matter if it is in/out of focus or even hidden. Downside is you don't get the regular fade out animation (it just vanishes). Also, if you need multiple tool tips at once you need to have multiple AutoItX3 objects.
You need Show/Hide it in the mouse events, also converting mouse location from Screen coordinate to your control coordinate. the little problem is if you put tooltip exactly on mous pointer location toolTip will catch mouseEnter event and unintended mouseLeave event on your control will be triggered so my solution was adding a little offset to final location.
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
Point p = pictureBox3.PointToClient(Cursor.Position);
p.X += 5;
p.Y += 5;
toolTip1.Show("My tooltip" ,
pictureBox1, p);
}
private void pictureBox1_MouseLeave(object sender, EventArgs e)
{
toolTip1.ShowAlways = false;
Text = ("Leave");
}
private void pictureBox1_MouseEnter(object sender, EventArgs e)
{
toolTip1.ShowAlways = true;
Text=("Enter");
}
It is a shame Winforms does not have a position property for tooltips.
The easiest thing I found is to add your own mouse-over and mouse-leave handlers and then use the Show() function to set the location (x and y), in pixels, relative to the upper left corner of the second argument of the Show() function.
The second argument can be any control, but probably makes most sense to use the control containing the tooltip itself (this), the parent the control, or a child control inside the control.
You can use a Point instead of two arguments (x and y) for the position, but remember Show() will take the point's x coordinate and y coordinate and add them to the x and y coordinates of the upper left corner of the control you chose as the second argument.
private void UserControl1_MouseHover(object sender, EventArgs e)
{
toolTip1.Show("this text is so new", this, 10, 10);
}
private void UserControl1_MouseLeave(object sender, EventArgs e)
{
toolTip1.Hide(this);
}
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;
}
}
My form doesn't have a title bar, so I am implementing the code to drag
the entire form around the screen. I am using the below code to do it, which works fine.
I have two panels in my form, PanelA and PanelB. During the startup I show
PanelA where the dragging works perfectly. Later when the user clicks
the button in PanelA, I need to make PanelA invisible and show PanelB
However, the dragging does not work when PanelB is shown. What's the
problem here?
private void SerialPortScanner_MouseUp(object sender, MouseEventArgs e)
{
this.drag = false;
}
private void SerialPortScanner_MouseDown(object sender, MouseEventArgs e)
{
this.drag = true;
this.start_point = new Point(e.X, e.Y);
}
private void SerialPortScanner_MouseMove(object sender, MouseEventArgs e)
{
if (this.drag)
{
Point p1 = new Point(e.X, e.Y);
Point p2 = this.PointToScreen(p1);
Point p3 = new Point(p2.X - this.start_point.X,
p2.Y - this.start_point.Y);
this.Location = p3;
}
}
Edit: I've realized that you're not asking about drag and drop, but rather about moving your form around the screen. (Thanks to #Veer.) I've edited your question to help clarify this. Drag and drop is a completely different thing, since it is dragging information from one control to another.
The same principle of my answer still applies though, since mouse events are also handled at the Control level - you might need to handle the mouse events from PanelB as well.