I have a winform window. When I change the size of the screen, the screen immediately increases or decreases.
I would prefer the Resize behavior of the window will be like Split Container, as long as I drag the mouse I see only line that marks what will be the window size, and only in leaving the Resize operation will be made.
I saw several examples that show that by hiding the frame of the window, and then by clicking on the window itself paint frame.
I want that by clicking on the frame of the window(I don't want to hide the frame) and not on the window.
Is there any way to do this? (May override the behavior of the Resize in any way).
I'm pretty sure that you can't find any solution on the Internet. However I've tried a demo for this and it works pretty well.
In winforms and many other UI technologies, you can't render something outside the window itself. To get the effect we want, we have to render some indicative border outside or inside the window depending on how user resizes it. So looks like we're stuck?
BUT there is a kind of technique to do that (I call it layer technique). We need a transparent, non-focused layer to render the indicative border. This layer will have its Size and Location synchronized with the Size and Location (with just a little offset) of the main window. The layer will also be invisible by default and only shows when user resizes and hides when ending resizing.
That's pretty OK with the technique I mentioned. However how to prevent/discard the default resizing when user resizes the window? It's luckily that Win32 supports 2 messages for this to be done easily:
WM_RESIZING : is sent to the window when user starts and keeps resizing. The LParam holds the RECT structure of the current window when resizing. We read this info to render the indicative border correctly. Then we need to modify this RECT to the current Bounds of the window to discard the default resizing effect (the size and location are changed immediately).
WM_EXITSIZEMOVE : is sent to the window when the resizing or moving ends. We need to catch this message to assign the Size and Location of the window based on the Size and Location of the transparent layer and of course hide the layer then.
Now the problem is totally solvable. Here is the demo code I've made. Note that there is a very nasty unsolvable and incomprehensible bug here, it happens when you resize the Top-Left corner, the Size is updated correctly after releasing mouse but the Location is set with an offset. I've debugging but no luck. At some point the Top and Left jumps to unexpected values for no clear reason. However, resizing by all the sides (left, top, right, bottom) and other corners is OK. In fact, resizing by the Top-Left corner is hardly done by user so this solution is acceptable, I think.
//Must add using System.Runtime.InteropServices;
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
//Sizing border initialization
SizingBorderWidth = 3;
SizingBorderStyle = DashStyle.Custom;
SizingBorderColor = Color.Orange;
//layer initialization
layer.Owner = this;//especially this one.
layer.Width = Width + SizingBorderWidth * 2;
layer.Height = Height + SizingBorderWidth * 2;
//Paint the border when sizing
layer.Paint += (s, e) => {
using (Pen p = new Pen(SizingBorderColor) { Width = SizingBorderWidth }) {
if (Use3DSizingBorder) {
ControlPaint.DrawBorder3D(e.Graphics, sizingRect.Left, sizingRect.Top, sizingRect.Width, sizingRect.Height, Border3DStyle.Bump, Border3DSide.All);
}
else {
p.DashStyle = SizingBorderStyle;
p.LineJoin = LineJoin.Round;
if(p.DashStyle == DashStyle.Custom)
p.DashPattern = new float[] { 8f, 1f, 1f, 1f };//length of each dash from right to left
e.Graphics.DrawRectangle(p, sizingRect);
}
}
};
//Bind the Location of the main form and the layer form together
LocationChanged += (s, e) => {
Point p = Location;
p.Offset(-SizingBorderWidth, -SizingBorderWidth);
layer.Location = p;
};
//Set the intial Location of layer
Load += (s, e) =>{
Point p = Location;
p.Offset(-SizingBorderWidth, -SizingBorderWidth);
layer.Location = p;
};
}
//Set this to true to use 3D indicative/preview border
public bool Use3DSizingBorder { get; set; }
//Change the indicative/preview border thickness
public int SizingBorderWidth { get; set; }
//Change the indicative/preview border style
public DashStyle SizingBorderStyle { get; set; }
//Change the indicative/preview border color
public Color SizingBorderColor { get; set; }
//hold the current sizing Rectangle
Rectangle sizingRect;
bool startSizing;
bool suppressSizing;
//This is a Win32 RECT struct (don't use Rectangle)
public struct RECT
{
public int left, top, right, bottom;
}
protected override void WndProc(ref Message m)
{
if (m.Msg == 0x214&&!suppressSizing)//WM_SIZING = 0x214
{
RECT rect = (RECT) m.GetLParam(typeof(RECT));
int w = rect.right - rect.left;
int h = rect.bottom - rect.top;
sizingRect = new Rectangle() {X = SizingBorderWidth/2, Y = SizingBorderWidth/2,
Width = w, Height = h};
layer.Left = rect.left-SizingBorderWidth;
layer.Top = rect.top-SizingBorderWidth;
layer.Width = w+2*SizingBorderWidth;
layer.Height = h+2*SizingBorderWidth;
if (!startSizing)
{
layer.Show();
startSizing = true;
}
layer.Invalidate();
//Keep the current position and size fixed
rect.right = Right;
rect.bottom = Bottom;
rect.top = Top;
rect.left = Left;
//---------------------------
Marshal.StructureToPtr(rect, m.LParam, true);
}
if (m.Msg == 0x232)//WM_EXITSIZEMOVE = 0x232
{
layer.Visible = false;
BeginInvoke((Action)(() => {
suppressSizing = true;
Left = layer.Left + SizingBorderWidth;
Top = layer.Top + SizingBorderWidth;
Width = layer.Width - 2 * SizingBorderWidth;
Height = layer.Height - SizingBorderWidth * 2;
suppressSizing = false;
}));
startSizing = false;
}
base.WndProc(ref m);
}
//Here is the layer I mentioned before.
NoActivationForm layer = new NoActivationForm();
}
public class NoActivationForm : Form {
public NoActivationForm() {
//The following initialization is very important
TransparencyKey = BackColor;
FormBorderStyle = FormBorderStyle.None;
ShowInTaskbar = false;
StartPosition = FormStartPosition.Manual;
//----------------------------------------------
}
protected override bool ShowWithoutActivation {
get { return true; }
}
}
Some screen shots:
EDIT: (This edit was suggested by Hodaya Shalom, the OP (weird :)
I found a solution to the left corner problem :
before the BeginInvoke I save the variables and in the invoke I put the local variable:
int _top = layer.Top + SizingBorderWidth;
int _left = layer.Left + SizingBorderWidth;
int _width = layer.Width - 2 * SizingBorderWidth;
int _height = layer.Height - SizingBorderWidth * 2;
BeginInvoke((Action)(() => {
suppressSizing = true;
Left = _left;
Top = _top;
Width =_width;
Height =_height;
suppressSizing = false;
}));
Related
I have three monitors in the following configuration:
Monitor 1 Monitor 2 Monitor 3
[1280 x 1024] [1200 x 1900] [1280 x 1024]
I use a form to outline a selected monitor (code below), which works great when I initialize or change between Monitors 1 and 3, but results in two rectangles drawn when Monitor 2 is selected :/
I tried to modify the code in many-many different ways, but nothing seems to work. I thought someone might be able to help me understand why two rectangles are being drawn (1280 x 1024 and 1200 x 1900) and how to correct.
Thank you for your time, regards and happy New Year.
P.S. If possible, please keep explanation simple as I am still learning.
public partial class ScreenArea : Form
{
private Pen _pen;
private int screenSelect;
public ScreenArea(int selectScreen = 0)
{
//xInitializeComponent();
TopMost = true;
ShowInTaskbar = true;
FormBorderStyle = FormBorderStyle.None;
BackColor = Color.LightGreen;
TransparencyKey = Color.LightGreen;
_pen = new Pen(Color.Aqua, 5);
Paint += new PaintEventHandler(ScreenArea_Paint);
ScreenSelect = screenSelect;
}
private void ScreenArea_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawRectangle(_pen, 0, 0, Width, Height);
}
public int ScreenSelect
{
get
{
return screenSelect;
}
set
{
Rectangle screenBounds;
try
{
screenBounds = Screen.AllScreens[value].Bounds;
screenSelect = value;
}
catch (Exception)
{
screenBounds = Screen.AllScreens[screenSelect].Bounds;
}
this.Left = screenBounds.X;
this.Top = screenBounds.Y;
this.Width = screenBounds.Width;
this.Height = screenBounds.Height;
}
}
}
I'm trying to set the Height of the form while I'm resizing it, if a condition is met. I have it set to only allow the width of the form to be altered manually using the code provided by in this answer.
I have a FlowLayoutPanel displaying a collection of PictureBox controls, each with a fixed Height of 50 pixels. Initially, the form's Height is 38 (Size.Height - ClientSize.Height) + 50 + 6 (Margin.Top + Margin.Bottom of an image) = 94.
If the controls overflow, by default the FlowLayoutPanel pushes them down onto a new line. What I want to do is resize the form when this happens, or when the form width is manually changed which might cause the controls to jump to the next line.
The following code works, and is called whenever a new control is added to the FlowLayoutPanel (itemPanel):
private void ResizeForm()
{
if (itemPanel.Controls.Count < 1) return;
var lastElement = itemPanel.Controls[itemPanel.Controls.Count - 1];
// The Form is the correct size, no need to resize it:
if (lastElement.Bottom + lastElement.Margin.Bottom == itemPanel.Height) return;
Height = 38 + lastElement.Bottom + lastElement.Margin.Bottom;
}
However, when called within my SizeChange event, this method causes the Form to "flash" between the initial Height and the new Height:
private void MainForm_SizeChanged(object sender, EventArgs e)
{
ResizeForm();
}
I'm guessing the reason is because setting Height will fire the SizeChange event again, but I don't know how to resolve this issue. When I print out the values of lastElement.Bottom + lastElement.Margin.Bottom and itemPanel.Height after setting the Height, they are identical, but the code is still somehow reaching that point.
In a nutshell, I want only the form Width to be manually altered, but the Height of the form to change when items are added or the Width is changed, so that all controls inside the FlowLayoutPanel can be viewed.
However, when called within my SizeChange event, this method causes
the Form to "flash" between the initial Height and the new Height
Basically any of the stock "resize" events for your Form will occur too late for you to change the size without it being noticeable.
You'll want to trap the WM_SIZING message:
Sent to a window that the user is resizing. By processing this
message, an application can monitor the size and position of the drag
rectangle and, if needed, change its size or position.
This will allow you to change the size of the Form before it has actually been updated on the screen.
It would look something like this:
public partial class Form1 : Form
{
private struct RECT
{
public int Left;
public int Top;
public int Right;
public int Bottom;
}
enum HitTest
{
Caption = 2,
Transparent = -1,
Nowhere = 0,
Client = 1,
Left = 10,
Right = 11,
Top = 12,
TopLeft = 13,
TopRight = 14,
Bottom = 15,
BottomLeft = 16,
BottomRight = 17,
Border = 18
}
private const int WM_SIZING = 0x214;
private const int WM_NCHITTEST = 0x84;
public Form1()
{
InitializeComponent();
}
protected override void WndProc(ref Message m)
{
base.WndProc(ref m);
switch (m.Msg)
{
case WM_NCHITTEST:
var result = (HitTest)m.Result.ToInt32();
if (result == HitTest.Top || result == HitTest.Bottom)
m.Result = new IntPtr((int)HitTest.Caption);
if (result == HitTest.TopLeft || result == HitTest.BottomLeft)
m.Result = new IntPtr((int)HitTest.Left);
if (result == HitTest.TopRight || result == HitTest.BottomRight)
m.Result = new IntPtr((int)HitTest.Right);
break;
case WM_SIZING:
// Retrieve the "proposed" size of the Form in "rc":
RECT rc = (RECT)Marshal.PtrToStructure(m.LParam, typeof(RECT));
// ... do something with "rc" ...
// this is your code (slightly modified):
if (itemPanel.Controls.Count > 0)
{
var lastElement = itemPanel.Controls[itemPanel.Controls.Count - 1];
if (lastElement.Bottom + lastElement.Margin.Bottom != itemPanel.Height)
{
int Height = 38 + lastElement.Bottom + lastElement.Margin.Bottom;
rc.Bottom = rc.Top + Height; // <--- use "Height" to update the "rc" struct
}
}
// Put the updated "rc" back into message structure:
Marshal.StructureToPtr(rc, m.LParam, true);
break;
}
}
}
Give this a try:
private void ResizeForm()
{
this.SuspendLayout(); // Suspends the layout logic until ResumeLayout() is called (below)
if (itemPanel.Controls.Count < 1) return;
var lastElement = itemPanel.Controls[itemPanel.Controls.Count - 1];
// The Form is the correct size, no need to resize it:
if (lastElement.Bottom + lastElement.Margin.Bottom == itemPanel.Height) return;
Height = 38 + lastElement.Bottom + lastElement.Margin.Bottom;
this.ResumeLayout(); // ADD THIS AS WELL
}
I have a winform that starts out with a sizable border around it. On the form is a button which, when pressed, changes the form to border style none.
The problem is that then the inner part of the form moves up and to the left slightly. I want to make it that, no matter what border is used, the "inner" part of the form will always stay in the same spot (note: but I do still want the form to be moved around when it has a movable border selected)
Thanks.
The Borderless form moves up and slightly left because thats the location that the form currently has,you need to count for the border.To achieve the result you are after you need to reassign the location property and to do that you need to account for the client size and the whole size(with border),the code i think is simple and it will be self-explanatory i believe:
private void button1_Click(object sender, EventArgs e)
{
var X = (this.Size.Width - this.ClientRectangle.Width) / 2;
var Y = (this.Size.Height - this.ClientRectangle.Height) - X;
Point p = new Point(Location.X + X, Location.Y + Y);
this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
this.Location = p;
}
Another option is to set the padding on the parent that contains the panel with the border. E.g.
public class Form10 : Form {
Button btn = new Button { Text = "Button", Location = new Point(100, 100) };
Panel border = new Panel { Dock = DockStyle.Fill, BorderStyle = BorderStyle.Fixed3D };
public Form10() {
Controls.Add(border);
border.Controls.Add(btn);
btn.Click += delegate {
if (border.BorderStyle == BorderStyle.Fixed3D) {
border.BorderStyle = BorderStyle.None;
border.Parent.Padding = new Padding(2);
}
else {
border.BorderStyle = BorderStyle.Fixed3D;
border.Parent.Padding = new Padding(0);
}
};
}
}
I'm using this code:
private void notifyIcon1_MouseDoubleClick(object sender, MouseEventArgs e)
{
this.Show();
this.WindowState = FormWindowState.Normal;
//this.Location = new Point(form1_location_on_x, form1_location_on_y);
//this.StartPosition = FormStartPosition.CenterScreen;
Either the line
this.Location = new Point(form1_location_on_x, form1_location_on_y);
or the line
this.StartPosition = FormStartPosition.CenterScreen;
are working when I'm on my original screen resolution 1920x1080, but once I'm changing the resolution to 1024x768, the Form is on the right bottom corner not hidden I see it all but it's not in the center.
form1_location_on_x and on_y are:
form1_location_on_x = this.Location.X;
form1_location_on_y = this.Location.Y;
The question is what should I do to make it work on any other resolution like 1024x768 or any others? I tried many changes but nothing worked so far.
Size screenSize = Screen.PrimaryScreen.WorkingArea.Size;
Location = new Point(screenSize.Width / 2 - Width / 2, screenSize.Height / 2 - Height / 2);
Make sure that you set StartPosition = FormStartPosition.Manual;
Tested and working with 1920x1080 and 1024 x 768
You could calculate the top and left position of your form using this formula:
int formWidth = yourForm.Width;
int formHeight = yourForm.Height;
int screenH = (Screen.PrimaryScreen.WorkingArea.Top +
Screen.PrimaryScreen.WorkingArea.Height) / 2;
int screenW = (Screen.PrimaryScreen.WorkingArea.Left +
Screen.PrimaryScreen.WorkingArea.Width) / 2;
int top = screenH - formWidth / 2;
int left = screenW - formHeight / 2;
yourForm.Location = new Point(top, left);
Of course, these days, you have the problem of dual monitors.
I don't know if you want your form to appear always on the primary screen or you want the form appear in the current screen (the one where the form is currently displayed). In this second case you need to find where your form is displayed
private void CenterForm(Form yuorForm)
{
foreach(var s in Screen.AllScreens)
{
if(s.WorkingArea.Contains(yourForm.Location))
{
int screenH = s.WorkingArea.Height / 2;
int screenW = s.WorkingArea.Width / 2;
int top = (screenH + s.WorkingArea.Top) - formWidth / 2;
int left = (screenW + s.WorkingArea.Left) - formHeight / 2;
yourForm.Location = new Point(top, left);
break;
}
}
}
EDIT: Thanks to #alex I will complete the answer with the information on SystemEvents class
If you want to be notified by the system when the user suddenly change the resolution of your screen you could subscribe to the event SystemEvents.DisplaySettingsChanged (using Microsoft.Win32; needed)
SystemEvents.DisplaySettingsChanged += new EventHandler(SystemEvents_DisplaySettingsChanged);
and then handle the reposition of your form in the event
// This method is called when the display settings change.
void SystemEvents_DisplaySettingsChanged(object sender, EventArgs e)
{
RecenterForm(yourForm);
}
try using one of these after the resize:
this.CenterToScreen();
or
this.CenterToParent();
You can use StartPosition property of Form objects. It determines the position of a form. Set it's value to CenterScreen if you want your form to open in the center of the screen
I'm making instrument to select part of image. I have PictrureBox, and simple way to make it :
void StartPanel(object sender, MouseEventArgs args)
{
xStart = args.X;
yStart = args.Y;
panelStarted = true;
pan.Location = new Point(xStart, yStart);
}
void FinishPanel(object sender, MouseEventArgs args)
{
xFinish = args.X;
yFinish = args.Y;
panelStarted = false;
}
void UpdatePanel(object sender, MouseEventArgs args)
{
if (panelStarted)
{
int x = args.X;
int y = args.Y;
int newxstart = xStart;
int newystart = yStart;
int neww = 0;
int newh = 0;
if (x >= xStart)
neww = x - xStart;
else
{
neww = xStart - x;
newxstart = x;
}
if (y >= yStart)
newh = y - yStart;
else
{
newh = yStart - y;
newystart = y;
}
pan.Size = new Size(neww, newh);
pan.Location = new Point(newxstart, newystart);
}
}
When I move mouse right and down, it is absolutely ok. But when I move it left or up I can see blinks at my area. So I have understood, that it is because when I move mouse left or up, my panel is redrawed, because Panel.Location is changed, and when I move mouse right and down, location is not changed, only size is changed, so it is not redrawed, just some pixels are added to panel. What is standart solution for this?
It's not easy trying to see what you are trying to do, but I guess you are using a panel as a draggable control to drag over the picturebox surface capturing the portion of image below (like a lens) - yes?
If so, then this is not the best way to do it. It is better to just draw a rectangle on the picturebox surface and "drag" that around - this is simple with just using the mouse events to sets the top left corner and use the onpaint to draw the unfilled rectangle over the image. Capturing the image when you are ready is simple too using whatever event you wish, then copy the image giving the same positions to the new bitmap.
Putting one control over another often causes flickers - even with double buffering. It also takes far more code.
Since you are describing a drawing issue when resizing the panel, probably the easiest fix is to replace the panel you are using with one that is double buffered and will invalidate on resize a event:
public class BufferedPanel : Panel {
public BufferedPanel() {
this.DoubleBuffered = true;
this.ResizeRedraw = true;
}
}