Slide object using For Loop (C#) - c#

I did quite a bit of searching around and didn't find anything of much help.
Is it possible to "slide" or "move" using C#, an object from one Location to another using a simple For loop?
Thank you

I would suggest you rather use a Timer. There are other options, but this will be the simplist if you want to avoid threading issues etc.
Using a straight for loop will require that you pump the message queue using Application.DoEvents() to ensure that windows has the opportunity to actually render the updated control otherwise the for loop would run to completion without updating the UI and the control will appear to jump from the source location to the target location.
Here is a QAD sample for animating a button in the Y direction when clicked. This code assumes you put a timer control on the form called animationTimer.
private void button1_Click(object sender, EventArgs e)
{
if (!animationTimer.Enabled)
{
animationTimer.Interval = 10;
animationTimer.Start();
}
}
private int _animateDirection = 1;
private void animationTimer_Tick(object sender, EventArgs e)
{
button1.Location = new Point(button1.Location.X, button1.Location.Y + _animateDirection);
if (button1.Location.Y == 0 || button1.Location.Y == 100)
{
animationTimer.Stop();
_animateDirection *= -1; // reverse the direction
}
}

Assuming that the object you're talking about is some kind of Control you could just change the Location property of it.
So something like this:
for(int i = 0; i < 100; i++)
{
ctrl.Location.X += i;
}
Should work I think.

Related

Edit Values of Shapes in List C#

Original Question: Edit properties of Graphics object c#
I've managed to create the object models and converted the entire program to use this structure so many thanks for the template there. My only problem is, I need to use threading to implement the color-changing feature. I have implemented the following code but have no luck:
private void pictureBox6_Click(object sender, EventArgs e)
{
running = !running;
}
public void redgreenMethod()
{
while (true)
{
if (running != true) continue;
if (flag == false)
{
flag = true;
Shape x = shapes[methodCounter - 1];
x.pen = Red;
}
else
{
flag = false;
Shape x = shapes[methodCounter];
x.pen = Green;
}
Thread.Sleep(500);
}
}
Surely the code inside the "if" statement changes the pen for the most recently added shape? I've entered a breakpoint and it shows that the pen does change constantly.. however, I don't see this being implemented on the Canvas?!
Where am I going wrong?!
From my previous comment:
Most likely redgreenMethod() is running in the main UI thread and the
tight loop is preventing the controls from updating themselves. Use a
TIMER instead. Set its Interval property to 500, and handle the Tick()
event. You don't need the while loop then. Instead of running you just
toggle the Enabled state of the Timer.
Here's what that might look like in code:
private void pictureBox6_Click(object sender, EventArgs e)
{
timer1.Enabled = !timer1.Enabled;
}
private void timer1_Tick(object sender, EventArgs e)
{
flag = !flag;
shapes[methodCounter - 1].pen = flag ? Green : Red;
}
You made these comments in an answer to your previous question:
Once a line has been drawn via the graphics: "g.DrawLine", the
properties of this line are then inaccessible. I need to find out how
to actually access these properties so I can use them inside the
Thread method.
In short, you DON'T access the properties of the line that has already been drawn. What you would do is update the color in the Shape (which you're already doing), and then call Invalidate() against the control that needs to be redrawn, such as pictureBox6.Invalidate(). This will force the Paint() event to fire again where everything will then be re-drawn, presumably with the new color that was set in the Shape properties.

A random picturebox won't move when coded in Timer

I don't know if I still have missing on this but whenever you want to add PictureBox, you just find it on Toolbox and drag it on the UI. But what I did is I coded it by adding PictureBox then what I want is I have to move it to the right. I coded it on a Timer and this is how I do.
private void enemyMove_Tick(object sender, EventArgs e)
{
GameMenu menu = new GameMenu();
if (menu.cmbox_Level.Text.Equals("Easy"))
{
this.Controls.Add(menu.EnemyTank);
menu.EnemyTank.Width = 26;
menu.EnemyTank.Height = 32;
menu.EnemyTank.BackgroundImage = Properties.Resources.Tank_RIGHT_v_2;
menu.EnemyTank.BackgroundImageLayout = ImageLayout.Stretch;
menu.EnemyTank.Left += 2;
}
}
Don't ask me if the Timer is started. Yes it already started, it was coded on the Form. But somehow when I start the program it doesn't move. But then I tried adding PictureBox, this time I tried dragging it to UI then add an Image on it, then coded it by moving to the right. When I start the program it works. But what I want is that whenever I start the button it will just make the random PictureBox move to the right. Idk what's the missing in here.
I made some assumptions. If I my assumptions aren't correct, please update your post for details. Following content is copied from my comment.
A new GameMenu will always create a new EnemyTank.
A EnemyTank's default Left value is fixed;
Your enemyMove_Tick is keep creating GameMenu and EnemyTank.
That is, every tick, a EnemyTank is created and value changed to "default value plus 2" in your code.
To avoid it, you have to keep EnemyTank instance somewhere instead of keep creating it.
Here's a example.
GameMenu m_menu;
void YourConstructor()
{
// InitializeComponent();
// something else in your form constructor
m_menu = new GameMenu();
m_menu.EnemyTank.Width = 26;
m_menu.EnemyTank.Height = 32;
m_menu.EnemyTank.BackgroundImage = Properties.Resources.Tank_RIGHT_v_2;
m_menu.EnemyTank.BackgroundImageLayout = ImageLayout.Stretch;
this.Controls.Add( m_menu.EnemyTank );
}
private void enemyMove_Tick(object sender, EventArgs e)
{
if (menu.cmbox_Level.Text.Equals("Easy"))
{
m_menu.EnemyTank.Left += 2;
}
}

Background worker for search and highlight feature

I have a simple while loop that allows me to find text within a textbox, but when I am searching for a word that appears several times in the textbox, it locks up the interface for a while. I'd like to move it into a background worker, but I don't think this can be done because the interface elements (i.e. textbox3.text) are on the main thread. How can I make a background worker when the main interface elements are involved?
I found decent information on the web, but I am having trouble implementing other solutions I have read into my particular situation.
public void button2_Click(object sender, EventArgs e)
{
//Highlight text when search button is clicked
int index = 0;
while (index < dragDropRichTextBox1.Text.LastIndexOf(textBox3.Text))
{
dragDropRichTextBox1.Find(textBox3.Text, index, dragDropRichTextBox1.TextLength, RichTextBoxFinds.None);
dragDropRichTextBox1.SelectionBackColor = Color.Orange;
index = dragDropRichTextBox1.Text.IndexOf(textBox3.Text, index) + 1;
}
}
Thanks for the help.
I guess what you want to do is create sub thread doing the job not to block the UI thread ( pseudo-code, aka not tested ) :
public void button2_Click(object sender, EventArgs e)
{
// Copy text in a non-thread protected string, to be used within the thread sub-routine.
string searchText = textBox3.Text;
string contentText = dragDropRichTextBox1.Text;
// Create thread routine
ThreadPool.QueueUserWorkItem(o => {
// Iterate through all instances of the string.
int index = 0;
while (index < contentText.LastIndexOf(searchText))
{
dragDropRichTextBox1.Invoke((MethodInvoker) delegate {
// Update control within UI thread
//Highlight text when search button is clicked
dragDropRichTextBox1.Find(searchText, index, contentText.Length, RichTextBoxFinds.None);
dragDropRichTextBox1.SelectionBackColor = Color.Orange;
}
// Go to next instance
index = contentText.IndexOf(searchText, index) + 1;
}
});
}
Again, this is untested, but that would give you the idea.
-- EDIT --
You don't need threading at all, doing all the work between a dragDropRichTextBox1.SuspendLayout() and dragDropRichTextBox1.ResumeLayout() is enough.
private void button1_Click(object sender, EventArgs e)
{
// Copy text in a non-thread protected string, to be used within the thread sub-routine.
string searchText = textBox1.Text;
string contentText = richTextBox1.Text;
// Suspend all UI refresh, so time won't be lost after each Find
richTextBox1.SuspendLayout();
// Iterate through all instances of the string.
int index = 0;
while (index < contentText.LastIndexOf(searchText))
{
//Highlight text when search button is clicked
richTextBox1.Find(searchText, index, contentText.Length, RichTextBoxFinds.None);
richTextBox1.SelectionBackColor = Color.Orange;
// Go to next instance
index = contentText.IndexOf(searchText, index) + 1;
}
// Finally, resume UI layout and at once get all selections.
richTextBox1.ResumeLayout();
}
You just need to use invoke when you're manipulating the UI elements in your background thread
https://msdn.microsoft.com/en-us/library/vstudio/ms171728(v=vs.100).aspx
You can call the Invoke Method on the control.
dragDropRichTextBox1.Invoke((MethodInvoker) delegate {
//Your code goes here for whatever you want to do.
}
);
This should fix your problem.

How to display data received from serial port in a textbox without the text disappearing in Visual Studio C#?

So, I'm trying to develop a simple application in visual C# which gets data from serial port and displays it in a textbox (to monitor temperature). I'm acquiring and displaying the data successfully, using the DataReceived event to update a global string variable and a timer to update the text field on my text box, as shown:
private void port_DataReceived_1(object sender, SerialDataReceivedEventArgs e)
{
try
{
globalVar.updateTemp = port.ReadLine(); //This is my global string
}
catch (IOException)
{
}
catch (InvalidOperationException)
{
}
catch (TimeoutException)
{
}
}
private void timer1_Tick(object sender, EventArgs e)
{
tempDisplayBox.Text = globalVar.updateTemp; //This is my textbox updating
}
The only issue I have is that the value shown in the textbox keeps flashing, making it hard to read. My timer is set to trigger every 10 ms (which should be fast enough, right?). Is there any way to make it more stable? I realize this may be a newb question, but to be fair I am a newb :) Any help is appreciated! Thanks!
Do you really need it updating every 10ms? What about every 500 ms or if not that then 100ms. 100ms will require your update method run 10 times less and therefore update 10 times less. The flickering you are expiriencing is due to the refresh speed. You could create custom method which will only update the temp only when target Label or textBox value is different than source port. But that will only sort the flickering when temp is steady, when temp will start vary it will bring back the flickering. Good luck ;-)
UPDATE
Hi I tried to reproduce the conditions and could not make my textbox nor Label flash. The way I tested it was by assigning int ntick = 0; and then increment the ++ntick; inside of the timer_tick method. The results didn't make any of the controls flash and were updated even every milisecond at some point. I also tried string.Format to put some load on the method. Is your app responsive?
The trick is to use double buffering. This way the operating system will redraw the Control off-screen, and only show the control when it is fully redrawn.
I have had the same problem, and solved it by extending the TextBox control like this:
public FastLogBox()
{
InitializeComponent();
_logBoxText = new StringBuilder(150000);
timer1.Interval = 20;
timer1.Tick += timer1_Tick;
timer1.Start();
SetStyle(ControlStyles.DoubleBuffer, true);
}
void timer1_Tick(object sender, EventArgs e)
{
if (_timeToClear)
{
_logBoxText.Clear();
_timeToClear = false;
}
if (_logQueue.Count <= 0) return;
while (!_logQueue.IsEmpty)
{
string element;
if (!_logQueue.TryDequeue(out element)) continue;
{
_logBoxText.Insert(0, element + "\r\n");
}
}
if (_logBoxText.Length > 150000)
{
_logBoxText.Remove(150000, _logBoxText.Length - 150001);
}
Text = _logBoxText.ToString();
}
public new void Clear()
{
_timeToClear = true;
while (!_logQueue.IsEmpty)
{
string element;
_logQueue.TryDequeue(out element);
}
}
public void AddToQueue(string message)
{
_logQueue.Enqueue(message);
}
}
I also use a timer and a concurrentQueue to avoid using Invoke to update the control from another thread. I also use a StringBuilder to prepare the string before putting it into the TextBox. StringBuilder is faster when building larger strings.
You can use ReadExisting() to read the whole data at a time.
You need to handle DataReceived Event of SerialPort
serialPort1.ReadExisting();
Sample:
private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
String myData=serialPort1.ReadExisting();
}
Example Code: Here i would like to show you the code to Read Data(RFID Tag Code which is basically of length 12)
String macid = "";
private void DoWork()
{
Invoke(
new SetTextDeleg(machineExe ),
new object[] { macid });
macid = "";
}
private void serialPort1_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
{
string str1;
macid += serialPort1.ReadExisting();
if (macid.Length == 12)
{
macid = macid.Substring(0, 10);
Thread t = new Thread(new ThreadStart(DoWork));
t.Start();
}
}
public void machineExe(string text)
{
TextBox1.Text=text;
}
Thank you so much for the answers! I found a way to work around this issue:
Instead of replacing the contents of my textbox by rewriting the TextBox.Text property - which, as HenningNT implied, refreshes the control and causes the flickering - I'm now using the TextBox.AppendText method. Though, as I want to display only one line of data at a time, I use the textbox in multiline mode and the Environment.NewLine to jump to a new line before appending the text. As for the method of updating, I've gone back to using the timer because with the invoke method was crashing my application when I close the form, for some reason. Also, enabling double buffering didn't do me much good, although I guess I was doing it wrong... It still flickers a bit, but it's much better now :) I know this is not really a perfect solution (much more of a workaround), so I'll keep looking for it. If I find it, I'll be sure to update it here ;) My code:
private void timer1_Tick(object sender, EventArgs e) //Timer to update textbox
{
if (tempDisplayBox.Text != globalVar.updateTemp) //Only update if temperature is different
{
try
{
tempDisplayBox.AppendText(Environment.NewLine);
tempDisplayBox.AppendText(globalVar.updateTemp);
}
catch (NullReferenceException)
{
}
}
}

Better algorithm to fade a winform

While searching for code to fade a winform, I came across this page on the MSDN forum.
for (double i = 0; i < 1; i+=0.01)
{
this.Opacity = i;
Application.DoEvents();
System.Threading.Thread.Sleep(0);
}
The for loop has a non-integer increment and, from a previous question I asked, that's not a good programming technique (due to inexact representation of most decimals).
I came up with this alternative.
for (double i = 0; i < 100; ++i)
{
this.Opacity = i/100;
Application.DoEvents();
System.Threading.Thread.Sleep(0);
}
Which of these is more efficient?
If there's a better algorithm for fading a form, I'll be very glad if it is included.
Thanks.
Forget timers (pun intended).
With Visual Studio 4.5 or higher, you can just await a task that is delayed. An advantage of this method is that it's asynchronous, unlike a thread Sleep or DoEvents loop, which blocks the application during the fade (and the other aforementioned DoEvents problems).
private async void FadeIn(Form o, int interval = 80)
{
//Object is not fully invisible. Fade it in
while (o.Opacity < 1.0)
{
await Task.Delay(interval);
o.Opacity += 0.05;
}
o.Opacity = 1; //make fully visible
}
private async void FadeOut(Form o, int interval = 80)
{
//Object is fully visible. Fade it out
while (o.Opacity > 0.0)
{
await Task.Delay(interval);
o.Opacity -= 0.05;
}
o.Opacity = 0; //make fully invisible
}
Usage:
private void button1_Click(object sender, EventArgs e)
{
FadeOut(this, 100);
}
You should check if the object is disposed before you apply any transparency to it. I used a form as the object, but you can pass any object that supports transparency as long as it's cast properly.
So, first off, application.DoEvents should be avoided unless you really know what you're doing and are sure that this is both an appropriate use of it, and that you are using it correctly. I'm fairly certain that neither is the case here.
Next, how are you controlling the speed of the fading? You're basically just letting the computer fade as quickly as it can and relying on the the inherent overhead of the operations (and background processes) to make it take longer. That's really not very good design. You're better off specifying how long the fade should take from the start so that it will be consistent between machines. You can use a Timer to execute code at the appropriate set intervals and ensure that the UI thread is not blocked for the duration of the fade (without using DoEvents).
Just modify the duration below to change how long the fade takes, and modify the steps to determine how "choppy" it is. I have it set to 100 because that's effectively what your code was doing before. In reality, you probably don't need that many and you can just lower to just before it starts getting choppy. (The lower the steps the better it will perform.)
Additionally, you shouldn't be so worried about performance for something like this. The fade is something that is going to need to be measured on the scale of about a second or not much less (for a human to be able to perceive it) and for any computer these days it can do so, so much more than this in a second it's not even funny. This will consume virtually no CPU in terms of computation over the course of a second, so trying to optimize it is most certainly micro-optimizing.
private void button1_Click(object sender, EventArgs e)
{
int duration = 1000;//in milliseconds
int steps = 100;
Timer timer = new Timer();
timer.Interval = duration / steps;
int currentStep = 0;
timer.Tick += (arg1, arg2) =>
{
Opacity = ((double)currentStep) / steps;
currentStep++;
if (currentStep >= steps)
{
timer.Stop();
timer.Dispose();
}
};
timer.Start();
}
I wrote a class specifically for fading forms in and out. It even supports ShowDialog and DialogResults.
I've expanded on it as I've needed new features, and am open to suggestions. You can take a look here:
https://gist.github.com/nathan-fiscaletti/3c0514862fe88b5664b10444e1098778
Example Usage
private void Form1_Shown(object sender, EventArgs e)
{
Fader.FadeIn(this, Fader.FadeSpeed.Slower);
}
for (double i = 0; i < 1; i+=0.01)
{
this.Opacity = i;
Application.DoEvents();
System.Threading.Thread.Sleep(0);
}
is more efficient as the number of floating point divisions are more machine-expensive than compared to floating point additions(which do not affect vm-flags). That said, you could reduce the number of iterations by 1/2(that is change step to i+=0.02). 1% opacity reduction is NOT noticeable by the human brain and will be less expensive too, speeding it up almost 100% more.
EDIT:
for(int i = 0; i < 50; i++){
this.Opacity = i * 0.02;
Application.DoEvents();
System.Threading.Thread.Sleep(0);
}
I applied the approach of Victor Stoddard to a splashScreen. I used it in the Form_Load event to fadeIn and FormClosing event to fadeOut.
NOTE: I had to set the form's opacity to 0 before call the fadeIn method.
Here you can see the order of events rised by a winform (lifecycle):
https://msdn.microsoft.com/en-us/library/86faxx0d(v=vs.110).aspx
private void Splash_Load(object sender, EventArgs e)
{
this.Opacity = 0.0;
FadeIn(this, 70);
}
private void Splash_FormClosing(object sender, FormClosingEventArgs e)
{
FadeOut(this, 30);
}
private async void FadeIn(Form o, int interval = 80)
{
//Object is not fully invisible. Fade it in
while (o.Opacity < 1.0)
{
await Task.Delay(interval);
o.Opacity += 0.05;
}
o.Opacity = 1; //make fully visible
}
private async void FadeOut(Form o, int interval = 80)
{
//Object is fully visible. Fade it out
while (o.Opacity > 0.0)
{
await Task.Delay(interval);
o.Opacity -= 0.05;
}
o.Opacity = 0; //make fully invisible
}
In the past, I've used AnimateWindow to fade in/out a generated form that blanks over my entire application in SystemColor.WindowColor.
This neat little trick gives the effect of hiding/swapping/showing screens in a wizard like interface. I've not done this sort of thing for a while, but I used P/Invoke in VB and ran the API in a thread of its own.
I know your question is in C#, but it's roughly the same. Here's some lovely VB I've dug out and haven't looked at since 2006! Obviously it would be easy to adapt this to fade your own form in and out.
<DllImport("user32.dll")> _
Public Shared Function AnimateWindow(ByVal hwnd As IntPtr, ByVal dwTime As Integer, ByVal dwFlags As AnimateStyles) As Boolean
End Function
Public Enum AnimateStyles As Integer
Slide = 262144
Activate = 131072
Blend = 524288
Hide = 65536
Center = 16
HOR_Positive = 1
HOR_Negative = 2
VER_Positive = 4
VER_Negative = 8
End Enum
Private m_CoverUp As Form
Private Sub StartFade()
m_CoverUp = New Form()
With m_CoverUp
.Location = Me.PointToScreen(Me.pnlMain.Location)
.Size = Me.pnlMain.Size
.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None
.BackColor = Drawing.SystemColors.Control
.Visible = False
.ShowInTaskbar = False
.StartPosition = System.Windows.Forms.FormStartPosition.Manual
End With
AnimateWindow(m_CoverUp.Handle, 100, AnimateStyles.Blend) 'Blocks
Invoke(New MethodInvoker(AddressOf ShowPage))
End Sub
Private Sub EndFade()
AnimateWindow(m_CoverUp.Handle, 100, AnimateStyles.Blend Or AnimateStyles.Hide)
m_CoverUp.Close()
m_CoverUp = Nothing
End Sub
Victor Stoddard is close, but I found that the fade was more pleasing if it started the opacity increase fast and slowed as it approached full opacity of 1. Here's a slight modification to his code:
using System.Threading.Tasks;
using System.Windows.Forms;
public partial class EaseInForm : Form
{
public EaseInForm()
{
InitializeComponent();
this.Opacity = 0;
}
private async void Form_Load(object sender, EventArgs e)
{
while (this.Opacity < 1.0)
{
var percent = (int)(this.Opacity * 100);
await Task.Delay(percent);
this.Opacity += 0.04;
}
}
}

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