I set a background of a picturebox as an image, which is fine.
I try to draw pen lines over the background image, but the lines do not appear on top of the image
This should happen: (I changed the code and not a clue what I changed to get this to happen, but this is without resetting the picturebox)
The picturebox is updated every 2000ms to show the flag signals, but can't for the life of me get the lines to appear.
Here are the bits of code:
lblSelectedChar.Text = inputchar.ToString();
picSemaphore.BackgroundImage = semaphore.Properties.Resources.human;
leftHandDown();
rightHandLow();
The leftHandDown() and rightHandLow() methods draw the lines, but I think they are drawn behind the image. I would like them drawn in front. Any idea how I would do this?
private void leftHandDown()
{
lblLeftHand.Hide();
display.DrawLine(penLeftArm, centXCoord, centYCoord, LHDownXCoord, LHDownYCoord);
lblLeftHand.Top = LHDownYCoord + 74;
lblLeftHand.Left = LHDownXCoord + 13;
lblLeftHand.Show();
lblLeftHand.Update();
}
Also, when the label is moved, it leaves a white space where it last was. Any idea how to stop this happening?
As LarsTech suggested, use the Paint() event of your PictureBox to draw the lines with the supplied Graphics via the e.Graphics value. You'd call picSemaphore.Refresh(); to make the lines update.
Here's a quick example to give you the basic idea:
public partial class Form1 : Form
{
private bool displayLeftArmLine = false;
private bool displayRightArmLine = false;
public Form1()
{
InitializeComponent();
picSemaphore.Paint += new PaintEventHandler(picSemaphore_Paint);
}
void picSemaphore_Paint(object sender, PaintEventArgs e)
{
if (displayLeftArmLine)
{
e.Graphics.DrawLine(penLeftArm, centXCoord, centYCoord, LHDownXCoord, LHDownYCoord);
}
if (displayRightArmLine)
{
e.Graphics.DrawLine(penRightArm, centXCoord, centYCoord, RHDownXCoord, RHDownYCoord);
}
}
private void leftHandDown()
{
lblLeftHand.Hide();
lblLeftHand.Top = LHDownYCoord + 74;
lblLeftHand.Left = LHDownXCoord + 13;
lblLeftHand.Show();
lblLeftHand.Update();
displayLeftArmLine = true;
picSemaphore.Refresh(); // force Paint() event for "picSemaphore" to fire
}
}
Related
I have a program which has 16 grid tiles using picturebox but only uses 5 images, the rest of the tiles are just a black image.
I would like to be able to tell which image the 'user' clicks on.
I have a method called image_Click(object sender, EventArgs e)
I have an if statement inside this method that states:
if (peckedSquare.BackColor == Color.Black)
{
System.Diagnostics.Debug.WriteLine("Pecked a black square");
return;
}
This sends a String that lets me know when a black square has been clicked.
Is there an easy way to perhaps say:
//pseudo code:
if (peckedSquare.ImageName == pigeon1.png)
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
I have googled my query but I have not found any suitable answers.
//EDIT
I have just re-read my code.
I was assigning each picture to a picturebox square using a randomnumber.
I had this random number as a variable, so I can just use that variable to determine which image was clicked.
ie.
if (randomNumber == 1)
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
or better than that
pigeonSelected = randomNumber + 1 //as I am using an array to store the images
System.Diagnostics.Debug.WriteLine("Pecked Pigeon Number {0}", pigeonSelected);
As quick & dirty solution I would use Tag property for that, null for black tiles and file path for the others (and it's always available, even if your image comes from resources), something like this:
if (peckedSquare.Tag == null)
{
Debug.WriteLine("Pecked a black square");
}
else
{
switch (Path.GetFileName(peckedSquare.Tag.ToString()))
{
case "pigeon1.png":
break;
}
}
Of course when you create tiles you have to store file path in Tag:
PictureBox tile = new PictureBox();
tile.Image = Image.FromFile(path); // Or another source, of course
tile.Tag = path;
As alternative you may even use Name property for this, each control is named (primary for designer-code integration) but if you create controls at run-time you can set that value to anything you want (not only valid identifiers). Same usage as above just no need to call ToString().
How to Improve?
Please let me say this solution is not very OOP. Even without a big refactoring we can do little bit better. Note that you can store whatever you want in Tag property. A number, a simple string unrelated to file name or even (maybe better) a class or an enum that represents that image (to delegate action to that object). This is a very raw example:
abstract class Tile {
public abstract void Activate();
}
sealed class EmptyTile : Tile {
public virtual void Activate() {
Debug.WriteLine("Pecked a black square");
}
}
sealed class ImageTile : Tile {
public ImageTile(string content) {
_content = content;
}
public virtual void Activate() {
Debug.WriteLine(_content);
}
private string _content;
}
In this way in your click event handler you can do this:
((Tile)peckedTile.Tag).Activate();
No need to check what's inside or to compare with null. No if and no switch, just don't forget to put proper object (ImageTile or BlackTile) when you create tiles.
Use PictureBox.Load(string) method to load images from file. Then the file path will be stored in the
PictureBox.ImageLocation property:
A call to the Load method will overwrite the ImageLocation property, setting ImageLocation to the URL value specified in the method call.
So you can write for example:
if (peckedSquare.ImageLocation.EndsWith("pigeon1.png"))
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
I think you could do something like the following:
private List<PictureBox> pictures = null;
string[] ImageNames = new string[]
{
"images\\test_1.jpg",
"images\\test_2.jpg"
};
private void Form1_Load(object sender, EventArgs e)
{
pictures = new List<PictureBox>();
for (var idx = 0; idx < ImageNames.Length; idx++)
{
pictures.Add(new PictureBox());
pictures[idx].Image = new Bitmap(ImageNames[idx]);
pictures[idx].Click += OnClick;
// you'll want to set the offset and everything so it shows at the right place
Controls.Add(pictures[idx]);
}
}
private void OnClick(object sender, EventArgs eventArgs)
{
// you'll definitely want error handling here
var ImageName = ImageNames[pictures.IndexOf((PictureBox) sender)];
}
You can see that in the click method you will be able to get the image name, which is what you are looking for I believe.
As others have said, you can also use the "Tag" property assuming you weren't already using this for some other purpose. The nice thing about tag is you can probably also edit it through the form designer which allows you to lay things out a little more nicely than the automatic layout I used above. Good luck!
You can do something like this using the Tag property like #Adriano suggested:
public Form1()
{
InitializeComponent();
pictureBox1.Click += pictureBox_Click;
pictureBox2.Click += pictureBox_Click;
pictureBox3.Click += pictureBox_Click;
// ...
pictureBox1.Tag = "picture1.png";
pictureBox2.Tag = "picture2.png";
pictureBox3.Tag = "picture3.png";
}
void pictureBox_Click(object sender, EventArgs e)
{
PictureBox pb = sender as PictureBox;
if (pb.BackColor != Color.Black)
Debug.WriteLine(pb.Tag.ToString());
else
Debug.WriteLine("Black image");
}
I am trying to print automatically a series of Windows-Forms. I don't need to show them. The code examples I found on the internet work only when I display the Form with show()! I need to initialize the form with data and send it to the printer Here is the code I am using:
public partial class Form2_withoutShow : Form{
PrintDocument PrintDoc;
Bitmap memImage;
public Form2_withoutShow (Data data)
{
InitializeComponent();
/*
Initialize Data (texboxes, charts ect.) here
*/
this.PrintDoc = new PrintDocument();
this.PrintDoc.PrintPage += PrintDoc_PrintPage;
this.PrintDoc.DefaultPageSettings.Landscape = true;
}
public void Print()
{
this.PrintDoc.Print();
}
void PrintDoc_PrintPage(object sender, PrintPageEventArgs e)
{
int x = SystemInformation.WorkingArea.X;
int y = SystemInformation.WorkingArea.Y;
int width = this.Width;
int height = this.Height;
Rectangle bounds = new Rectangle(x, y, width, height);
Bitmap img = new Bitmap(width, height);
this.DrawToBitmap(img, bounds);
Point p = new Point(10, 10);
e.Graphics.DrawImage(img, p);
}
private void Form2_withoutShow_Load(object sender, EventArgs e)
{
// remove TITLEBar
this.ControlBox = false;
this.Text = String.Empty;
}
}
I call the Print() method from another class in for-loop and pass the Data to be initialized through the constructor.
The MSDN example captures the part on the screen where the forms should be displayed. This doesn't work for me. The approach I am using now yields only the print of the empty Window if I don't call show(). How do I get the data into the form without having to call the show() method? Approaches like mimize the windows when displaying it, also don't work because that is also the print result: a minimized window.
Before showing the form, the form and its controls are not in Created state. To force the form and its controls to be created it's enough to call internal CreateControl(bool fIgnoreVisible) method of your form:
var f = new Form1();
var createControl = f.GetType().GetMethod("CreateControl",
BindingFlags.Instance | BindingFlags.NonPublic);
createControl.Invoke(f, new object[] { true });
var bm = new Bitmap(f.Width, f.Height);
f.DrawToBitmap(bm, new Rectangle(0, 0, bm.Width, bm.Height));
bm.Save(#"d:\bm.bmp");
Also remove codes which you have in your form Load event handler, and put them in constructor of your form.
Note
There are also other workarounds for the problem:
For example you can show the form in a location outside of boundary of the screen and then hide it again. Set the Location to (-32000, -32000) and set StartPosition to be Manual then Show and Hide the form before drawing to bitmap.
Or as another example, you can show the form with Opacity set to 0 and then Show and Hide the form before drawing to bitmap.
OK so I am new to C# and I am confused about how events work. currently I have a panel in which I am drawing rectangles. the event is called when the panel is initialized but I want to call it after I do something in my data Grid. I simply want to know how to tell the object to update.
Do I not use an event in this situation? If so do I just create a new graphics instance and start?
Here is my code:
private void panel6_Paint(object sender, PaintEventArgs e)
{
if(dataGridView1.RowCount != 0 )
{
Pen lightRed = new Pen(Brushes.LightSalmon);
lightRed.Width = 1.0F;
lightRed.LineJoin = System.Drawing.Drawing2D.LineJoin.Miter;
int counter = 0;
foreach (var pair in currentPosition)
{
if(dataGridView1[0, counter].Style.BackColor == Color.Red)
{
e.Graphics.DrawRectangle(lightRed, new Rectangle(0, currentPosition.Count / panel6.Height * counter, 66, currentPosition.Count / panel6.Height * counter));
}
}
lightRed.Dispose();
}
}
Whenever you want to force a redraw, call:
Invalidate();
...or
Refresh();
Invalidate() is preferred...Refresh() attempts to be more immediate.
So, for your panel:
panel6.Invalidate();
You would call this at any point where you want to signal to the control that it should repaint itself. That will result in your Paint event firing.
I have a program which has 16 grid tiles using picturebox but only uses 5 images, the rest of the tiles are just a black image.
I would like to be able to tell which image the 'user' clicks on.
I have a method called image_Click(object sender, EventArgs e)
I have an if statement inside this method that states:
if (peckedSquare.BackColor == Color.Black)
{
System.Diagnostics.Debug.WriteLine("Pecked a black square");
return;
}
This sends a String that lets me know when a black square has been clicked.
Is there an easy way to perhaps say:
//pseudo code:
if (peckedSquare.ImageName == pigeon1.png)
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
I have googled my query but I have not found any suitable answers.
//EDIT
I have just re-read my code.
I was assigning each picture to a picturebox square using a randomnumber.
I had this random number as a variable, so I can just use that variable to determine which image was clicked.
ie.
if (randomNumber == 1)
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
or better than that
pigeonSelected = randomNumber + 1 //as I am using an array to store the images
System.Diagnostics.Debug.WriteLine("Pecked Pigeon Number {0}", pigeonSelected);
As quick & dirty solution I would use Tag property for that, null for black tiles and file path for the others (and it's always available, even if your image comes from resources), something like this:
if (peckedSquare.Tag == null)
{
Debug.WriteLine("Pecked a black square");
}
else
{
switch (Path.GetFileName(peckedSquare.Tag.ToString()))
{
case "pigeon1.png":
break;
}
}
Of course when you create tiles you have to store file path in Tag:
PictureBox tile = new PictureBox();
tile.Image = Image.FromFile(path); // Or another source, of course
tile.Tag = path;
As alternative you may even use Name property for this, each control is named (primary for designer-code integration) but if you create controls at run-time you can set that value to anything you want (not only valid identifiers). Same usage as above just no need to call ToString().
How to Improve?
Please let me say this solution is not very OOP. Even without a big refactoring we can do little bit better. Note that you can store whatever you want in Tag property. A number, a simple string unrelated to file name or even (maybe better) a class or an enum that represents that image (to delegate action to that object). This is a very raw example:
abstract class Tile {
public abstract void Activate();
}
sealed class EmptyTile : Tile {
public virtual void Activate() {
Debug.WriteLine("Pecked a black square");
}
}
sealed class ImageTile : Tile {
public ImageTile(string content) {
_content = content;
}
public virtual void Activate() {
Debug.WriteLine(_content);
}
private string _content;
}
In this way in your click event handler you can do this:
((Tile)peckedTile.Tag).Activate();
No need to check what's inside or to compare with null. No if and no switch, just don't forget to put proper object (ImageTile or BlackTile) when you create tiles.
Use PictureBox.Load(string) method to load images from file. Then the file path will be stored in the
PictureBox.ImageLocation property:
A call to the Load method will overwrite the ImageLocation property, setting ImageLocation to the URL value specified in the method call.
So you can write for example:
if (peckedSquare.ImageLocation.EndsWith("pigeon1.png"))
{
System.Diagnostics.Debug.WriteLine("Pecked Pigeon number 1");
}
I think you could do something like the following:
private List<PictureBox> pictures = null;
string[] ImageNames = new string[]
{
"images\\test_1.jpg",
"images\\test_2.jpg"
};
private void Form1_Load(object sender, EventArgs e)
{
pictures = new List<PictureBox>();
for (var idx = 0; idx < ImageNames.Length; idx++)
{
pictures.Add(new PictureBox());
pictures[idx].Image = new Bitmap(ImageNames[idx]);
pictures[idx].Click += OnClick;
// you'll want to set the offset and everything so it shows at the right place
Controls.Add(pictures[idx]);
}
}
private void OnClick(object sender, EventArgs eventArgs)
{
// you'll definitely want error handling here
var ImageName = ImageNames[pictures.IndexOf((PictureBox) sender)];
}
You can see that in the click method you will be able to get the image name, which is what you are looking for I believe.
As others have said, you can also use the "Tag" property assuming you weren't already using this for some other purpose. The nice thing about tag is you can probably also edit it through the form designer which allows you to lay things out a little more nicely than the automatic layout I used above. Good luck!
You can do something like this using the Tag property like #Adriano suggested:
public Form1()
{
InitializeComponent();
pictureBox1.Click += pictureBox_Click;
pictureBox2.Click += pictureBox_Click;
pictureBox3.Click += pictureBox_Click;
// ...
pictureBox1.Tag = "picture1.png";
pictureBox2.Tag = "picture2.png";
pictureBox3.Tag = "picture3.png";
}
void pictureBox_Click(object sender, EventArgs e)
{
PictureBox pb = sender as PictureBox;
if (pb.BackColor != Color.Black)
Debug.WriteLine(pb.Tag.ToString());
else
Debug.WriteLine("Black image");
}
I want to change form size depending on Screen and it's resolution.
What I want is a correct event to track these screen changes as well as screen resolution changes at runtime.
In other words,
If user is using two screens and move application to another screen, that should be tracked and change size accordingly, i.e. reduce size if new screen's resolution is low or increase size if resolution is larger.
Also track screen resolution change on the same screen, and make changes to size accordingly.
I know how to change Form size, get current screen and it's resolution, just need these events to keep track of these changes.
Going over this answer I've decided to improve it and add further information to form a more complete solution.
The Challenge
Tracking which screen a Form is currently being rendered on. This can change if a user drags the form to another monitor or unplugs a monitor. The resolution can change if a user manually drags a window to a different display or changes the resolution directly.
Firstly, tracking form location. We need to hook into a Move event for the form context, fortunately the .Net framework provides such an event, and it is named Control.Move Event.
Secondly, we will need to hook into a screen resolution changed event, we can do this with the SystemEvents.DisplaySettingsChanged event.
And putting it together, I got this:
struct Resolution
{
public int Width;
public int Height;
}
int previous = -1;
int current = -1;
private bool CheckScreenChanged()
{
bool changed = false;
current = GetScreenIndex();
if (current != -1 && previous != -1 && current != previous) // form changed screen.
{
changed = true;
}
previous = current;
return changed;
}
private int GetScreenIndex()
{
return Array.IndexOf(Screen.AllScreens, Screen.FromControl(this));
}
private Resolution GetCurrentResolution()
{
Screen screen = Screen.FromControl(this);
Resolution res = new Resolution();
res.Width = screen.Bounds.Width;
res.Height = screen.Bounds.Height;
return res;
}
private void SetResolutionLabel()
{
Resolution res = GetCurrentResolution();
label2.Text = String.Format("Width: {0}, Height: {1}", res.Width, res.Height);
}
private void ScreenChanged()
{
label1.Text = "Screen " + current.ToString();
}
private void Form_Moved(object sender, System.EventArgs e)
{
bool changed = CheckScreenChanged();
if (changed == true)
{
ScreenChanged();
SetResolutionLabel();
}
}
public void SystemEvents_DisplaySettingsChanged(object sender, EventArgs e)
{
SetResolutionLabel();
}
public void Initialize()
{
this.Move += Form_Moved;
SystemEvents.DisplaySettingsChanged += new
EventHandler(SystemEvents_DisplaySettingsChanged);
previous = GetScreenIndex();
current = GetScreenIndex();
ScreenChanged();
SetResolutionLabel();
}
The code above is tested on a simple form with two labels called label1 and label2, which are updated when the screen the form is on changes or the resolution changes.
An image of this in action on my primary screen/display
And on my secondary screen/display when the form has been dragged to it: