I'm drawing an image in a form. When the image is too wide, I want to increase the width of the form. Here's how I do it in the constructor:
ImageForm(String^ _path, int _w, int _h)
{
InitializeComponent();
if(this->ClientSize.Width <= _w)
{
this->ClientSize.Width = _w+2;
}
}
But it doesn't work. Even if the if-branch gets executed, the width of the form remains unchanged.
Things that you draw are not considers clients since they are not objects, you can notice that if you resize the form manually, they will disappear. this is why we use PictureBox for drawing.
Hope that it's useful.
Related
hoping you could help me out with the sizing if my forms. on my school laptop the form fits nicely to the resolution. however, on my personal laptop, the form does not fit the larger res and for some reason is more zoomed. I have sent pictures too
You get you screen resolution with following code:
Screen.PrimaryScreen.Bounds.Width;
Screen.PrimaryScreen.Bounds.Height;
you could adjust the position from every control in the form_load event with Control.Location or the size with Control.Size depending on the width and height of your screen.
For example
label1.Location.X = Screen.PrimaryScreen.Bounds.Width - 100;
label1.Location.Y = Screen.PrimaryScreen.Bounds.Height - 50;
If you want your control to always be fullscreen, you could also add this.WindowState = FormWindowState.Maximized; in the form_load event. then its easier to adjust the positions of the controls depending on screen size.
I am completely new to this forum, and still a beginner on WPF.
I am working on a project that requires the strokes on an inkcanvas to be animated. One of the animations required is "disappearing". I want to make the selected strokes gradually disappear with the click of a button, but appear at the end of the animation.
Since there is no opacity property for stroke, I tried using the ColorAnimation class along with storyboards. I have failed to make this code work, as I cannot target the strokes either using themselves or using their names, since they don't have any.
Right now I am thinking of implementing this system by gradually changing the color of the strokes to the color of the background, and at the end, resetting it back to its initial value. This is a costly loop, but I have no other ideas.
I would appreciate it if there are any other solutions you might share with me.
Thanks in advance.
Edit: I have not answered the comments, as I was dealing with other parts of the same project.
I have tried using the Alpha values that are stored in the DrawingAttributes, but I cannot change the value as it is not a variable. The same goes with RGB values. I have no idea on how to make the strokes disappear in a loop. I have already implemented most of the project, so I just need something to slowly make them disappear. Below you can find an example where I change the stroke itself to animate it.
private int dropOffset = 1;
private void DropAnimation()
{
m = new Matrix();
m.Translate(0, dropOffset);
animStrokes.Transform(m, false);
YChange += dropOffset;
dropOffset += 2;
}
And in another class, I have
public void AnimateStrokes(Dispatcher canvasDispatch)
{
Stopwatch initial = Stopwatch.StartNew();
while (initial.ElapsedMilliseconds < 2000)
{
foreach (Animation ai in AnimationList)
{
ai.animateSelected();
}
canvasDispatch.Invoke(new Action(() => { }), DispatcherPriority.Render);
Thread.Sleep(50);
}
foreach (Animation a in AnimationList)
{
a.undoAnimation();
}
canvasDispatch.Invoke(new Action(() => { }), DispatcherPriority.Render);
}
I know that it's not healthy to pass dispatcher like this, but it suffices for now.
Thanks again in advance.
InkCanvas1.DefaultDrawingAttributes.Color = Color.FromArgb(100, 0, 255, 255);
Might be a bit late but help for others none the less! The 100 is the alpha value which basically acts like an opacity value!! Mess with that and you will be able to change how transparent your strokes are :)
I have a panel and on that I've a picturebox. There are around 20 labels that I've to show in the panel. I want the background of Label to be transparent ie the image in picturebox is shown and the label displays only the text.
Now since labels do not exhibit true transparency I made the labels child of picturebox
this.lbl1.Parent = pictureBox1;
This has solved my immediate problem but now when the form loads, all the labels take a while to become visible and do so one at a time. I'd appreciate if you guys can give some solution for this.
Thanks in advance
The standard cure for flicker is double-buffering. But that cannot solve this kind of flicker. It is a different kind, caused by having multiple windows overlapping each other. Each label is its own window. When the form needs to paint itself, it draws its background leaving holes for the child windows. Each child window then takes a turn drawing itself. And their child windows draw themselves next. Etcetera.
This becomes noticeable when one control takes a while to draw, no doubt your picture box. Especially when it displays a large image that needs to be resized. The holes for the child windows stay unpainted while the picture box draws. They have a white background, black when you use the form's TransparencyKey or Opacity property. This can contrast badly with the image in your picture box, that effect is perceived by the user as flicker.
One immediate cure is to not use controls so you don't pay for their window. A Label is very convenient but it is a massive waste of system resources to burn up a window just to display a string. You can simply implement the picture box' Paint event and draw the strings with TextRenderer.DrawText(). PictureBox has double-buffering turned on by default so the image as well as the text is drawn completely smoothly, no more flicker. The obvious disadvantage is that you lose the convenience of point-and-click, you have to write code.
There are other fixes possible. One of them is to prevent the picture box from leaving holes for the child windows. It will draw the entire image, the labels pop on top of them. That's still flicker but not nearly as noticeable. Add a new class to your project and paste this code:
using System;
using System.Windows.Forms;
internal class MyPictureBox : PictureBox {
protected override CreateParams CreateParams {
get {
var parms = base.CreateParams;
parms.Style &= ~0x02000000; // Turn off WS_CLIPCHILDREN
return parms;
}
}
}
Compile and drop the new picture box control from the top of the toolbox onto your form.
Yet another possible workaround is to make the form and all of its children double-buffered. This doesn't speed up the painting at all but all of the windows get rendered into a memory buffer, the result is blitted to the screen. You'll notice a delay but the window suddenly pops on the screen. This is called compositing. Winforms doesn't support this directly since it can have side-effects but it is easy to enable. Paste this code into your form class:
protected override CreateParams CreateParams {
get {
CreateParams cp = base.CreateParams;
cp.ExStyle |= 0x02000000; // Turn on WS_EX_COMPOSITED
return cp;
}
}
Supported by XP and later. Watch out for painting artifacts.
or you can ditch the labels and draw the text yourself:
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
TextRenderer.DrawText(e.Graphics, "Label1", SystemFonts.DefaultFont,
new Point(10, 10), Color.Black, Color.Empty);
}
The label does not support transparency, you must create your own unique custom control, you can see these code examples.
http://www.codeproject.com/KB/dotnet/transparent_controls_net.aspx http://www.codeproject.com/KB/vb/uLabelX.aspx
Bye
I have a borderless form (FormBorderStyle = None) with the height of 23 pixels (set in the designer)
When .NET draws my form at runtime - it draws it 38 pixels high (it adds the height of a title-bar for some reason).
MessageBox.Show(this.Height.ToString()); //this shows 38!! why?
To work it around I have to set "Height = 23;" in the Form_Load event.
private void MyForm_Load(object sender, EventArgs e)
{
this.Height = 23; //workaround. wtf??
}
You can try this yourself in Visual Studio 2010 (Winforms App, target Framework - 2.0).
Wtf?
Yeah, it is a bug, of sorts. Note how in the designer you set the size of the form with the Width and Height properties. Those properties include the size of the borders and the title bar. That's a problem however, your form may run on a machine where the user has increased, say, the title bar font size. That then would reduce the size of the window's client area. Or in other words, the form's ClientSize property would change on that machine. Leaving less room for the controls and messing up the design of your form pretty badly.
There's code inside the Form class that runs after the Handle is created, right before the Load event runs. It recalculates the Size of the form, using the same ClientSize you had on your machine. Now everything is good, the Height of the form won't match the one you set in the designer but the form otherwise looks the same and the layout of the controls is identical.
That same code also ensures that the window doesn't get too small. And that's where it falls over, it doesn't pay enough attention to the FormBorderStyle property. Clipping the height to the title bar size plus the client area height, as you found out. It also prevents the form getting too narrow, trying to make sure that the icon and min/max/close buttons are always visible. Even if you don't have any.
The workaround is to change the ClientSize after this code runs, the OnLoad override or Load event handler is the right place for that. Beware that if you hard-code the form size like this then you should also set the AutoScaleMode property to None. Make sure that this doesn't cause trouble on a machine that has a different DPI setting.
You all know the "You've got new answers!" notification bar on SO. I'd like the same thing in a Form, preferably just as smooth. Is there a simple way? Or do I have to completely create this myself?
My searches did not yield any good results, only lots of progress bars and popups in the system notification area, but that's not what I'm looking for.
The messages I want to display belong to a Form, not to the whole application
You could simply animate a panel dropping down from the top of the client area of the form.
Increasing the y coordinate of the panel in a timed loop. The panel would start invisible and slowly become visible. (The panel would start at -panel.height and work its way down to 0.)
Create two panels in your form, a notification panel docked to top, and below that a content panel anchored to top. In your Form.Load, set the height of the notification panel to zero. Don't set the height to zero in Design View, you won't be able to click on the notification panel to edit it.
Then when you get a notification, draw the contents in the notification panel and create a System.Windows.Form.Timer that increases the height of the notification panel by a few pixels every few dozen milliseconds or so. Stop when the panel is of the desired height. Do the same with a negative height to hide the panel.
This does not require repainting or recalculating sizes or positions of anything, does not overdraw anything, and looks slick. I have done this and it works.
If you want it constrained to a particular form, it should be easy enough to put a Panel on the form with its Dock set to DockStyle.Top, then place a label for the description and a button that hides it.
It's not difficult to do with a panel or a UserControl, but the fiddly part is making the contents of the form slide down as the bar slides down. To simplify that I would use a SplitContainer. The top splitpanel contains the notification bar and the splitter distance is initially 0. Slide the bar into view by incrementing the SplitterDistance property. Doing it this way means you don't have to worry about making the other contents of the form slide down (which is a hassle because it prevents you from using docking).
The only downside to using SplitContainer I can think of is that the animation of the bar will be slightly different: the text won't scroll down with the bar, it will be revealed in place as the bar slides down. If this bothers you, you can fix it by having the text (or your panel/custom control) slide down as you increase the splitter distance (only a couple more lines of code).
Showing the bar:
for (int i = 0; i <= 33; i++)
{
splitContainer1.SplitterDistance = i;
Thread.Sleep(5);
Refresh();
}
Hiding the bar:
for (int i = 33; i >= 0; i--)
{
splitContainer1.SplitterDistance = i;
Thread.Sleep(5);
Refresh();
}
Of course, if you don't mind the notification bar simply covering the top part of your form, then you can just do the whole thing very easily with a panel. :)
I was looking for the same thing just now and found this on code project
I have not used it yet, So I have no idea how solid it is.