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Curved bottom navigation bar in xamarin forms

I'm trying to create something like this https://miro.medium.com/max/162/1*yMtMLC3mdjndmVHzPY5Adw.png in xamarin forms tabbed page and I'm copying the code of this https://medium.com/#androidtutorial/draw-custom-shapes-in-curved-bottom-navigation-view-361c9a5507dd into my TabbedPageRenderer. The problem is that I'm not getting any result.
Code.
public partial class TabbedPages : TabbedPage
{
public TabbedPages ()
{
InitializeComponent();
this.Children.Add(new Page()
{
Title = "Home",
Icon = "homepage_icon"
});
this.Children.Add(new Page()
{
Title = "Home",
Icon = "homepage_icon"
});
this.Children.Add(new Page()
{
Title = "Home",
Icon = "homepage_icon"
});
this.Children.Add(new Page()
{
Title = "Home",
Icon = "homepage_icon"
});
}
Renderer.
[assembly: ExportRenderer(typeof(TabbedPages), typeof(BottomNavTabPageRenderer))]
namespace App.Droid.CustomRenderer
{
public class BottomNavTabPageRenderer : TabbedPageRenderer
{
private bool _isShiftModeSet;
private Path mPath;
private Paint mPaint;
private int CURVE_CIRCLE_RADIUS = 90;
// the coordinates of the first curve
private Android.Graphics.Point mFirstCurveStartPoint = new Android.Graphics.Point();
private Android.Graphics.Point mFirstCurveEndPoint = new Android.Graphics.Point();
private Android.Graphics.Point mFirstCurveControlPoint1 = new Android.Graphics.Point();
private Android.Graphics.Point mFirstCurveControlPoint2 = new Android.Graphics.Point();
//the coordinates of the second curve
private Android.Graphics.Point mSecondCurveStartPoint = new Android.Graphics.Point();
private Android.Graphics.Point mSecondCurveEndPoint = new Android.Graphics.Point();
private Android.Graphics.Point mSecondCurveControlPoint1 = new Android.Graphics.Point();
private Android.Graphics.Point mSecondCurveControlPoint2 = new Android.Graphics.Point();
private int mNavigationBarWidth;
private int mNavigationBarHeight;
public BottomNavTabPageRenderer(Context context)
: base(context)
{
init();
}
private void init()
{
mPath = new Path();
mPaint = new Paint();
mPaint.SetStyle(Paint.Style.FillAndStroke);
mPaint.Color = Android.Graphics.Color.White;
SetBackgroundColor(Android.Graphics.Color.Transparent);
}
protected override void OnSizeChanged(int w, int h, int oldw, int oldh)
{
base.OnSizeChanged(w, h, oldw, oldh);
BottomNavigationMenuView bottomNavigationMenuView = FindChildOfType<BottomNavigationMenuView>(ViewGroup);
mNavigationBarWidth = bottomNavigationMenuView.Width; // Width I'm getting is 720
mNavigationBarHeight = bottomNavigationMenuView.Height; // Height I'm getting is 112
// the coordinates (x,y) of the start point before curve
mFirstCurveStartPoint.Set((mNavigationBarWidth / 2) - (CURVE_CIRCLE_RADIUS * 2) - (CURVE_CIRCLE_RADIUS / 3), 0);
// the coordinates (x,y) of the end point after curve
mFirstCurveEndPoint.Set(mNavigationBarWidth / 2, CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4));
// same thing for the second curve
mSecondCurveStartPoint = mFirstCurveEndPoint;
mSecondCurveEndPoint.Set((mNavigationBarWidth / 2) + (CURVE_CIRCLE_RADIUS * 2) + (CURVE_CIRCLE_RADIUS / 3), 0);
// the coordinates (x,y) of the 1st control point on a cubic curve
mFirstCurveControlPoint1.Set(mFirstCurveStartPoint.X + CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4), mFirstCurveStartPoint.Y);
// the coordinates (x,y) of the 2nd control point on a cubic curve
mFirstCurveControlPoint2.Set(mFirstCurveEndPoint.X - (CURVE_CIRCLE_RADIUS * 2) + CURVE_CIRCLE_RADIUS, mFirstCurveEndPoint.Y);
mSecondCurveControlPoint1.Set(mSecondCurveStartPoint.X + (CURVE_CIRCLE_RADIUS * 2) - CURVE_CIRCLE_RADIUS, mSecondCurveStartPoint.Y);
mSecondCurveControlPoint2.Set(mSecondCurveEndPoint.X - (CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4)), mSecondCurveEndPoint.Y);
mPath.Reset();
mPath.MoveTo(0, 0);
mPath.LineTo(mFirstCurveStartPoint.X, mFirstCurveStartPoint.Y);
mPath.CubicTo(mFirstCurveControlPoint1.X, mFirstCurveControlPoint1.Y,
mFirstCurveControlPoint2.X, mFirstCurveControlPoint2.Y,
mFirstCurveEndPoint.X, mFirstCurveEndPoint.Y);
mPath.CubicTo(mSecondCurveControlPoint1.X, mSecondCurveControlPoint1.Y,
mSecondCurveControlPoint2.X, mSecondCurveControlPoint2.Y,
mSecondCurveEndPoint.X, mSecondCurveEndPoint.Y);
mPath.LineTo(mNavigationBarWidth, 0);
mPath.LineTo(mNavigationBarWidth, mNavigationBarHeight);
mPath.LineTo(0, mNavigationBarHeight);
mPath.Close();
}
protected override void OnDraw(Canvas canvas)
{
base.OnDraw(canvas);
canvas.DrawPath(mPath, mPaint);
}
private T FindChildOfType<T>(ViewGroup viewGroup) where T : Android.Views.View
{
if (viewGroup == null || viewGroup.ChildCount == 0) return null;
for (var i = 0; i < viewGroup.ChildCount; i++)
{
var child = viewGroup.GetChildAt(i);
var typedChild = child as T;
if (typedChild != null) return typedChild;
if (!(child is ViewGroup)) continue;
var result = FindChildOfType<T>(child as ViewGroup);
if (result != null) return result;
}
return null;
}
}}
Any help would be appreciated!

Fft in real time - AsioOut+SampleAggregator

I am currently working on my thesis project, this is an application that writes tablature by ASIO drivers. In short, write what you play. I'm new in all regards Naudio and I'm having poblemas to transform sound into FFT. I am capturing the sound with a device called "GuitarLink" which runs through ASIO4ALL.
So I need to compare frequencies for the chord in real time.
Currently, the program gives me two values, X and Y.
(I am using "SampleAggregator" Class and AsioOut)
MAIN
private SampleAggregator sampleAggregator = new(fftLength);
public MainWindow()
{
InitializeComponent();
dispatcherTimer.Tick += new EventHandler(SoClose);
dispatcherTimer.Interval = new TimeSpan(0, 0, 0, 0, 500);
dispatcherTimer.Start();
}
void SoClose(object sender, EventArgs e)
{
try
{
if (PBass)
{
sampleAggregator.PerformFFT = true;
sampleAggregator.FftCalculated += new EventHandler<FftEventArgs>(FftCalculated);
AsioOut asioOut = new();
BufferedWaveProvider wavprov = new(new WaveFormat(48000, 1));
asioOut.AudioAvailable += new EventHandler<AsioAudioAvailableEventArgs>(asio_DataAvailable);
asioOut.InitRecordAndPlayback(wavprov, 1, 25);
asioOut.Play();
I1E.Text = frecuencia.ToString();
}
}
catch
{
MessageBox.Show("Error de bajo presupuesto", "Obviamente algo anda mal");
}
}
private void FftCalculated(object sender, FftEventArgs e)
{
for (int i = 0; i < e.Result.Length; ++i)
{
A = e.Result[i].X;
B = e.Result[i].Y;
frecuencia = B;
Debug.WriteLine($"FFT: X={e.Result[i].X} Y={e.Result[i].Y}");
}
}
void asio_DataAvailable(object sender, AsioAudioAvailableEventArgs e)
{
byte[] buf = new byte[e.SamplesPerBuffer * 4];
for (int i = 0; i < e.InputBuffers.Length; i++)
{
Marshal.Copy(e.InputBuffers[i], buf, 0, e.SamplesPerBuffer * 4);
Marshal.Copy(buf, 0, e.OutputBuffers[i], e.SamplesPerBuffer * 4);
}
for (int i = 0; i < buf.Length; i = i + 4)
{
float sample = Convert.ToSingle(buf[i] + buf[i + 1] + buf[i + 2] + buf[i + 3]);
sampleAggregator.Add(sample);
}
e.WrittenToOutputBuffers = true;
}
SampleAggregator class
public class SampleAggregator
{
// FFT
public event EventHandler<FftEventArgs> FftCalculated;
public bool PerformFFT { get; set; }
// This Complex is NAudio's own!
private Complex[] fftBuffer;
private FftEventArgs fftArgs;
private int fftPos;
private int fftLength;
private int m;
public SampleAggregator(int fftLength)
{
if (!IsPowerOfTwo(fftLength))
throw new ArgumentException("FFT Length must be a power of two");
this.m = (int)Math.Log(fftLength, 2.0);
this.fftLength = fftLength;
this.fftBuffer = new Complex[fftLength];
this.fftArgs = new FftEventArgs(fftBuffer);
}
public void Add(float value)
{
if (PerformFFT && FftCalculated != null)
{
fftBuffer[fftPos].X = (float)(value * FastFourierTransform.HammingWindow(fftPos, fftLength));
fftBuffer[fftPos].Y = 0; // This is always zero with audio.
fftPos++;
if (fftPos >= fftLength)
{
fftPos = 0;
FastFourierTransform.FFT(true, m, fftBuffer);
FftCalculated(this, fftArgs);
}
}
}
static bool IsPowerOfTwo(int x) => (x & (x - 1)) == 0;
}
public class FftEventArgs : EventArgs
{
public Complex[] Result { get; private set; }
public string resultado = "";
[DebuggerStepThrough]
public FftEventArgs(Complex[] result) => Result = result;
void FftCalculated(object sender, FftEventArgs e)
{
}
}
Well the problem is that when I play a note, the values that are delivered are not affected.

Most Efficient way to do a swipe animation in Xamarin.forms - Android

I had to implement a way to navigate between different element that are stacked in xamarin.forms. In the code below, you can see that we already manage the ability to distinguish every single one of the child of the container. At the moment, what I have written works but I need some help figuring out if it’s the good way or if there is a better way or even, if I can improve what I’ve done.
Currently, when you swipe from left to right or whatever move, I just use a SimpleOnGestureListener.
Here are some samples of what we are currently achieving:
I declared my custom elements such as the container & the children and then I created the customRenderer for each of them in an android library (only working on android at the moment).
“MyContent” is simply a modified frame with a specific Draw method and an event for each move available (up, down, left, right).
Code of the container
using System;
using Xamarin.Forms;
namespace Elements
{
public class MyContainer : Layout<MyContent>
{
public MyContainer ()
{
}
protected override void LayoutChildren (double x, double y, double width, double height)
{
for (int i = 0; i < Children.Count ; i++) {
MyContent child = Children[i];
// skip invisible children
if(!child.IsVisible)
continue;
int soffset = Children.Count - i;
int eoffset = soffset - 1;
Rectangle startBoundingRegion = new Rectangle (12 * soffset + Padding.Left, 14 * soffset + Padding.Top, width - 24 * soffset, height - 8 * soffset);
Rectangle endBoundingRegion = new Rectangle (12 * eoffset + Padding.Left, 14 * eoffset + Padding.Top, width - 24 * eoffset, height - 8 * eoffset);
child.OriginalBounds = endBoundingRegion;
LayoutChildIntoBoundingRegion (child,startBoundingRegion);
child.LayoutTo(endBoundingRegion,100,Easing.Linear);
}
}
protected override SizeRequest OnSizeRequest (double widthConstraint, double heightConstraint)
{
var height = 0;
var minHeight = 0;
var width = 0;
var minWidth = 0;
for (int i = 0; i < Children.Count; i++) {
MyContent child = Children[i];
// skip invisible children
if(!child.IsVisible)
continue;
var childSizeRequest = child.GetSizeRequest (double.PositiveInfinity, height);
height = (int)Math.Max (height, childSizeRequest.Minimum.Height);
minHeight = (int)Math.Max (minHeight, childSizeRequest.Minimum.Height);
width += (int)childSizeRequest.Request.Width;
minWidth += (int)childSizeRequest.Minimum.Width;
}
return new SizeRequest (new Size (width, height), new Size (minWidth, minHeight));
}
}
}
Code of its renderer
{using ...}
[assembly: ExportRenderer (typeof(MyContainer), typeof(MyContainerRenderer))]
namespace MyApp
{
public class MyContainerRenderer : ViewRenderer<Layout<MyContent>,Android.Views.View>
{
private readonly MyContentGestureListener listener;
private readonly GestureDetector detector;
private bool isAnimating;
private MyContent currentMyContent;
public MyContainerRenderer ()
{
listener = new MyContentGestureListener();
detector = new GestureDetector(listener);
}
protected override void OnElementChanged (ElementChangedEventArgs<Layout<MyContent>> e)
{
base.OnElementChanged(e);
if (e.NewElement == null)
{
this.Touch -= HandleTouch;
listener.OnSwipeLeft -= HandleOnSwipeLeft;
listener.OnSwipeRight -= HandleOnSwipeRight;
listener.OnSwipeTop -= HandleOnSwipeTop;
listener.OnSwipeDown -= HandleOnSwipeDown;
listener.OnPanVertical -= HandleOnPanVertical;
listener.OnPanHorizontal -= HandleOnPanHorizontal;
}
if (e.OldElement == null)
{
this.Touch += HandleTouch;
listener.OnSwipeLeft += HandleOnSwipeLeft;
listener.OnSwipeRight += HandleOnSwipeRight;
listener.OnSwipeTop += HandleOnSwipeTop;
listener.OnSwipeDown += HandleOnSwipeDown;
listener.OnPanVertical += HandleOnPanVertical;
listener.OnPanHorizontal += HandleOnPanHorizontal;
}
}
void HandleTouch(object sender, TouchEventArgs e)
{
currentMyContent = ((MyContainer)this.Element).Children.Last();
if (!isAnimating) {
if (e.Event.Action == MotionEventActions.Down) {
currentMyContent.ScaleTo (1.01, 100, Easing.Linear);
} else if ( e.Event.Action == MotionEventActions.Up){
if (!isAnimating) {
isAnimating = true;
currentMyContent.ScaleTo (1, 100, Easing.Linear);
currentMyContent.LayoutTo (currentMyContent.OriginalBounds, 100, Easing.CubicIn);
isAnimating = false;
listener.ResetFlags ();
}
}
detector.OnTouchEvent (e.Event);
}
}
void HandleOnPanVertical(object sender, EventArgs distanceY)
{
Rectangle dest = new Rectangle (currentMyContent.Bounds.X,currentMyContent.Bounds.Y - ((EventArgs<float>)distanceY).Value,currentMyContent.Bounds.Width,currentMyContent.Bounds.Height);
currentMyContent.Layout(dest);
}
void HandleOnPanHorizontal(object sender, EventArgs distanceX)
{
Rectangle dest = new Rectangle (currentMyContent.Bounds.X - ((EventArgs<float>)distanceX).Value,currentMyContent.Bounds.Y,currentMyContent.Bounds.Width,currentMyContent.Bounds.Height);
currentMyContent.Layout (dest);
}
async void animateNext (MyContent mContent, Rectangle dest)
{
isAnimating = true;
await mContent.LayoutTo (dest, 150, Easing.Linear);
((MyContainer)this.Element).Children.Remove (mContent);
((MyContainer)this.Element).Children.Insert (0, mContent);
isAnimating = false;
}
void HandleOnSwipeLeft(object sender, EventArgs e)
{
currentMyContent.OnSwipeLeft();
Rectangle dest = new Rectangle (currentMyContent.Bounds.X,currentMyContent.Bounds.Y,currentMyContent.Bounds.Width,currentMyContent.Bounds.Height);
dest.Left -= Width;
animateNext (currentMyContent, dest);
}
void HandleOnSwipeRight(object sender, EventArgs e)
{
currentMyContent.OnSwipeRight();
Rectangle dest = new Rectangle (currentMyContent.Bounds.X,currentMyContent.Bounds.Y,currentMyContent.Bounds.Width,currentMyContent.Bounds.Height);
dest.Left += Width;
animateNext (currentMyContent, dest);
}
void HandleOnSwipeTop(object sender, EventArgs e)
{
Rectangle dest = new Rectangle (currentMyContent.Bounds.X, currentMyContent.Bounds.Y, currentMyContent.Bounds.Width, currentMyContent.Bounds.Height);
dest.Top -= Height;
animateNext (currentMyContent, dest);
}
void HandleOnSwipeDown(object sender, EventArgs e)
{
Rectangle dest = new Rectangle (currentMyContent.Bounds.X,currentMyContent.Bounds.Y,currentMyContent.Bounds.Width,currentMyContent.Bounds.Height);
dest.Top += Height;
animateNext (currentMyContent, dest);
}
}
class MyContentGestureListener : GestureDetector.SimpleOnGestureListener
{
private static int SWIPE_THRESHOLD = 50;
private static int SWIPE_VELOCITY_THRESHOLD = 20;
private bool isPanningV;
private bool isPanningH;
public event EventHandler OnSwipeDown;
public event EventHandler OnSwipeTop;
public event EventHandler OnSwipeLeft;
public event EventHandler OnSwipeRight;
public event EventHandler OnPanHorizontal;
public event EventHandler OnPanVertical;
public override bool OnScroll(MotionEvent ev1, MotionEvent ev2,float distanceX,float distanceY)
{
if (Math.Abs (distanceX) > Math.Abs (distanceY) && OnPanHorizontal != null && !isPanningV) {
isPanningH = true;
OnPanHorizontal (this,new EventArgs<float> (distanceX));
} else if (OnPanVertical != null && !isPanningH) {
isPanningV = true;
OnPanVertical (this, new EventArgs<float> (distanceY));
}
return base.OnScroll (ev1, ev2, distanceX, distanceY);
}
public override bool OnFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
{
float diffY = e2.GetY() - e1.GetY();
float diffX = e2.GetX() - e1.GetX();
if (Math.Abs(diffX) > Math.Abs(diffY) && Math.Abs(diffX) > SWIPE_THRESHOLD && Math.Abs(velocityX) > SWIPE_VELOCITY_THRESHOLD)
{
if (diffX > 0 && OnSwipeRight != null)
{
OnSwipeRight (this, null);
isPanningH = false;
}
else if (OnSwipeLeft != null) {
OnSwipeLeft (this, null);
isPanningH = false;
}
}
else if (Math.Abs(diffY) > SWIPE_THRESHOLD && Math.Abs(velocityY) > SWIPE_VELOCITY_THRESHOLD)
{
if (diffY > 0 && OnSwipeDown != null)
{
OnSwipeDown (this, null);
isPanningV = false;
}
else if (OnSwipeTop != null) {
OnSwipeTop (this, null);
isPanningV = false;
}
}
return base.OnFling (e1, e2, velocityX, velocityY);
}
public void ResetFlags(){
isPanningH = false;
isPanningV = false;
}
}
public class EventArgs<T> : EventArgs
{
public EventArgs(T value)
{
Value = value;
}
public T Value { get; private set; }
}
}

Graphical Timer control not working correctly

This is a custom control I have made, a graphical timer, however, it is not working correctly. As the time left decreases a pie is filled to represent the amount of time left decreasing, but it is decreasing with unexpected angles (which are output to the listbox for debugging purposes). How do I get it to work correctly? Also I'm very new to making Custom Controls (this is my first) so any pointers on good coding guidelines, what not to do, etc, would be very helpful.
using System;
using System.Drawing;
using System.Windows.Forms;
namespace TestCustomControl
{
class GraphicalTimer : Control
{
public Color Timer { get; set; }
public Color TimerEmpty { get; set; }
public Color BorderColor { get; set; }
private Timer t;
public int MaxTime { get; set; }
private int timeElapsed = 0;
public GraphicalTimer()
{
DoubleBuffered = true;
SetStyle(ControlStyles.SupportsTransparentBackColor, true);
BackColor = Color.Transparent;
t = new Timer();
t.Interval = 1000;
t.Tick += t_Tick;
}
public void Start()
{
t.Start();
}
public void Stop()
{
t.Stop();
}
public void Reset()
{
timeElapsed = 0;
Invalidate();
}
void t_Tick(object sender, EventArgs e)
{
timeElapsed += 1;
if (timeElapsed == MaxTime)
{
t.Dispose();
}
Invalidate();
}
private float getAngleFromTime()
{
if (timeElapsed == 0)
{
return 0;
}
else
{
MainWindow.lb.Items.Add((360 / (MaxTime / timeElapsed)).ToString());
return (360 / (MaxTime / timeElapsed));
}
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Graphics g = e.Graphics;
Rectangle rc = ClientRectangle;
g.FillEllipse(new SolidBrush(Timer), rc);
g.FillPie(new SolidBrush(TimerEmpty), rc, -90, getAngleFromTime());
g.DrawEllipse(new Pen(BorderColor, 4), rc);
Font font = new Font("Arial", (float)rc.Height * 0.4f, FontStyle.Bold, GraphicsUnit.Pixel);
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
g.DrawString((MaxTime - timeElapsed).ToString("D2"), font, new SolidBrush(Color.Black), new RectangleF((rc.Width - rc.Width / 2) / 2, (rc.Height - rc.Height / 2) / 2, rc.Width * 0.7f, rc.Height * 0.7f));
}
}
class MainWindow : Form
{
GraphicalTimer gt;
Button startButton;
Button stopButton;
Button resetButton;
public static ListBox lb;
public MainWindow()
{
this.Text = "Test Application";
gt = new GraphicalTimer();
gt.MaxTime = 20;
gt.BorderColor = Color.BurlyWood;
gt.Timer = Color.Aqua;
gt.TimerEmpty = Color.White;
gt.Top = 10;
gt.Left = 10;
gt.Width = 50;
gt.Height = 50;
this.Controls.Add(gt);
startButton = new Button();
startButton.Top = 70;
startButton.Left = 30;
startButton.AutoSize = true;
startButton.Text = "Start Timer";
startButton.Click += startButton_Click;
this.Controls.Add(startButton);
stopButton = new Button();
stopButton.Top = 70;
stopButton.Left = startButton.Right + 10;
stopButton.AutoSize = true;
stopButton.Text = "Stop Timer";
stopButton.Click += stopButton_Click;
this.Controls.Add(stopButton);
resetButton = new Button();
resetButton.Top = 70;
resetButton.Left = stopButton.Right + 10;
resetButton.AutoSize = true;
resetButton.Text = "Reset Timer";
resetButton.Click += resetButton_Click;
this.Controls.Add(resetButton);
lb = new ListBox();
lb.Top = resetButton.Bottom + 10;
lb.Left = 10;
lb.Width = this.ClientSize.Width - 20;
lb.Height = this.ClientSize.Height - lb.Top - 10;
this.Controls.Add(lb);
}
void resetButton_Click(object sender, EventArgs e)
{
gt.Reset();
}
void stopButton_Click(object sender, EventArgs e)
{
gt.Stop();
}
void startButton_Click(object sender, EventArgs e)
{
gt.Start();
}
}
class StartClass
{
static void Main()
{
MainWindow form = new MainWindow();
Application.EnableVisualStyles();
Application.Run(form);
}
}
}

You are using integers to calculate the angle, and in a way that can cause quite some jitters.
360 / (MaxTime / timeElapsed) will first evaluate temp = MaxTime / timeElapsed in integer arithmetics, and then 360 / temp also using integer division.
Try using floating point numbers for the calculation and then converting the final result into an integer value if you need it that way. Even writing 360 * timeElapsed / MaxTime might reduce the artifacts as you then first multiply 360 * timeElapsed which is accurate (unless timeElapsed is very large).

The method of calculating AngleForTime is wrong. Just replace your method with below code and it should do your job.
;)
private float getAngleFromTime()
{
if (timeElapsed == 0)
{
return 0;
}
else
{
MainWindow.lb.Items.Add((360*timeElapsed) / MaxTime ).ToString();
return (360*timeElapsed) / MaxTime ;
}
}

How to update progressbars individually (simultaneous downloads)

I´m currently trying to add parallel downloads to my application but I don´t know how to handle the DownloadProgressChangedEvent to display the progress in multiple progressbars.
I´m using a datagridview with predefined rows for each file the user is able to download and each row has a cell with a progressbar in it.
The problem now is, that I don´t know how to update each progressbar individually, because right now, all selected progressbars are showing the same percentage and they´re just jumping between the progress of download1 & download2.
Here´s the code im using:
To start the downloads:
private void download_button_Click(object sender, EventArgs e)
{
start = DateTime.Now;
download_button.Enabled = false;
Rows = dataGridView1.Rows.Count;
Checked = 0;
CheckedCount = 0;
//count the selected rows
for (i = 0; i < Rows; i++)
{
Checked = Convert.ToInt32(dataGridView1.Rows[i].Cells["checkboxcol"].FormattedValue);
CheckedCount += Checked;
richTextBox3.Text = CheckedCount.ToString();
}
for (int z = 1; z < CheckedCount; z++)
{
_MultipleWebClients = new WebClient();
_MultipleWebClients.DownloadFileCompleted += new AsyncCompletedEventHandler(_DownloadFileCompleted);
_MultipleWebClients.DownloadProgressChanged += new System.Net.DownloadProgressChangedEventHandler(_DownloadProgressChanged);
_MultipleWebClients.DownloadFileAsync(new Uri(_downloadUrlList[z].ToString()), #"F:\test" + z + ".mp4");
}
}
(I´m also unable to download more than two files simultaneously - the third download won´t start until the first two are finished)
DownloadProgressChangedEvent:
private void _DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
for (int c = 0; c < CheckedCount; c++)
{
dataGridView1.Rows[_downloadRowNrList[c]].Cells[3].Value = e.ProgressPercentage;
}
float size = ((e.TotalBytesToReceive / 1024) / 1024);
label1.Text = size.ToString();
double dn = (double)e.BytesReceived / 1024.0 / (DateTime.Now - start).TotalSeconds;
label2.Text = (dn.ToString("n") + " KB/s) " + e.ProgressPercentage);
}
The problem probably is, that all progressbars are using the same DownloadProgressChangedEvent, but I´m not sure how to create multiple of these events without knowing the needed number...
So i hope that someone is able to help me with this,
thanks in advance!

What you want to do is use the other DownloadFileAsync method:
http://msdn.microsoft.com/en-us/library/ms144197.aspx
The third parameter is a userToken which gets passed as part of the DownloadProgressChangedEventArgs (it's in the UserState property).
So, when you make the DownloadFileAsync call, pass in a unique token (an integer, or something else) that you can then associate with the progressBar that needs updating.
//(Snip)
//in download_button_Click, pass the row you are updating to the event.
for (int z = 1; z < CheckedCount; z++)
{
_MultipleWebClients = new WebClient();
_MultipleWebClients.DownloadFileCompleted += new AsyncCompletedEventHandler(_DownloadFileCompleted);
_MultipleWebClients.DownloadProgressChanged += new System.Net.DownloadProgressChangedEventHandler(_DownloadProgressChanged);
_MultipleWebClients.DownloadFileAsync(new Uri(_downloadUrlList[z].ToString()), #"F:\test" + z + ".mp4", dataGridView1.Rows[z]);
}
}
private void _DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
var rowToUpdate = (DataGridViewRow)e.UserState;
RowToUpdate["ProgressBar"].Value = e.ProgressPercentage;
RowToUpdate["TextProgress"].Value = e.ProgressPercentage;
RowToUpdate["BytesToRecive"].Value = ((e.TotalBytesToReceive / 1024) / 1024).ToString();
double dn = (double)e.BytesReceived / 1024.0 / (DateTime.Now - start).TotalSeconds;
RowToUpdate["Speed"].Value = (dn.ToString("n") + " KB/s) " + e.ProgressPercentage);
}

Sounds like you need a progress bar for multi-parted progress:
public partial class ProgressBarEx : ProgressBar
{
private readonly Dictionary<Guid, double> _partsProgress =
new Dictionary<Guid, double>();
private readonly Dictionary<Guid, double> _partsSizes =
new Dictionary<Guid, double>();
private double _value;
private double _maximum;
public ProgressBarEx()
{
this.InitializeComponent();
}
public int Parts
{
get { return this._partsSizes.Count; }
}
public new int Minimum { get; private set; }
public new double Maximum
{
get { return this._maximum; }
private set
{
this._maximum = value;
base.Maximum = (int)value;
}
}
public new double Value
{
get { return this._value; }
private set
{
this._value = value;
base.Value = (int)value;
}
}
[Obsolete("Not useable in ProgressBarEx.")]
public new int Step
{
get { return 0; }
}
public Guid AddPart(double size)
{
if (size <= 0)
{
throw new ArgumentException("size");
}
var partId = Guid.NewGuid();
this.Maximum += size;
this._partsSizes.Add(partId, size);
this._partsProgress.Add(partId, 0);
return partId;
}
public bool RemovePart(Guid partId)
{
double size;
if (!this._partsSizes.TryGetValue(partId, out size))
{
return false;
}
this.Maximum -= size;
this._partsSizes.Remove(partId);
this.Value -= this._partsProgress[partId];
this._partsProgress.Remove(partId);
return true;
}
public bool ContainsPart(Guid partId)
{
return this._partsSizes.ContainsKey(partId);
}
public double GetProgress(Guid partId)
{
return this._partsProgress[partId];
}
public void SetProgress(Guid partId, double progress)
{
if (progress < 0 || this._partsSizes[partId] < progress)
{
throw new ArgumentOutOfRangeException("progress");
}
this.Value += progress - this._partsProgress[partId];
this._partsProgress[partId] = progress;
}
public void AddProgress(Guid partId, double progress)
{
this.SetProgress(partId, progress + this._partsProgress[partId]);
}
[Obsolete("Not useable in ProgressBarEx.")]
public new void PerformStep()
{
}
}
Example usage:
public Form1()
{
InitializeComponent();
var pbe = new ProgressBarEx {Location = new Point(100, 100)};
this.Controls.Add(pbe);
for (var i = 0; i < 4; i++)
{
var size = i * 10 + 30;
var partId = pbe.AddPart(size);
var pb = new ProgressBar
{
Maximum = size,
Location = new Point(100, i * 30 + 130)
};
this.Controls.Add(pb);
var timer = new Timer {Interval = 1000 + i * 100};
timer.Tick += (sender, args) =>
{
pb.Value += 5;
pbe.AddProgress(partId, 5);
if (pb.Value == pb.Maximum)
{
timer.Stop();
}
};
timer.Start();
}
}