update pathgraphic only - graphics

I use the following code to draw line as following
private void Form1_Paint(object sender, PaintEventArgs e)
{
base.OnPaint(e);
path = new GraphicsPath(new Point[]{ new Point(10, 10),
new Point(100, 100) } ,
new byte[] {(byte)PathPointType.Start,
(byte)PathPointType.Line });
e.Graphics.DrawPath(Pens.Red, path);
}
I need when click a button to change the path and redraw it only so I use
private void button1_Click(object sender, EventArgs e)
{
for (int i = 0; i < path.PointCount; i++)
{
path.PathPoints[i].X += 100;
path.PathPoints[i].Y += 100;
}
Invalidate();
//path.
}
the problem no effect happened, and I don't want to refresh the container I draw on it

First, it will not give you any effect since you always create a new path in OnPaint. As a result you have the same picture. In order to change it you need at least move your path creation to the constructor or another initialization method
Second, PathPoint is an array of PointF, PointF is a structure, therefore it is immutable and you will not get a new point in array by doing so - PathPoints[i].X += 10

Related

C# Win Form - Main thread not responding when using background worker

I have a datagridview which is being populated by a DataTable through DataSource and i am using a backgroundworker for formatting of cells (back color and forecolor of cells) in datagridview.
BackgroundWorker bw = new BackgroundWorker();
private void Frm_Find_Load(object sender, EventArgs e)
{
bw.WorkerSupportsCancellation = true;
bw.DoWork += new DoWorkEventHandler(bw_DoWork);
bw.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bw_RunWorkerCompleted);
}
void bw_DoWork(object sender, DoWorkEventArgs e)
{
CheckForValidValues();
}
public bool CheckForValidValues()
{
dgv.Invoke((MethodInvoker)delegate()
{
for (int i = 0; i < Dt.Rows.Count; i++)
{
if (Dt.Rows[0]["Name"].ToString() == Value)
{
dgv.Rows[i].Cells["Name"].Style.BackColor = Color.FromArgb(255, 192, 192);
}
else
{
dgv.Rows[i].Cells["Name"].Style.BackColor = Color.White;
}
progressBar1.Invoke((MethodInvoker)(() => progressBar1.Value++));
}
});
this.Invoke((MethodInvoker)delegate()
{
BtnShow.Enabled = true;
dgv.Enabled = true;
});
}
private void btnSave_Click(object sender, EventArgs e)
{
if (bw.IsBusy == false)
{
progressBar1.Visible = true;
progressBar1.Value = 0;
BtnShow.Enabled = false;
dgv.Enabled = false;
progressBar1.Maximum = dgv.Rows.Count;
bw.RunWorkerAsync();
}
}
while the whole process goes down the DataGridView remains Enabled=false so that user cant change any values in datagridview.
There is usually 15,000 rows in the datagridview and that many rows to format, this takes time that is why I use a backgroundworker for it and it works perfectly fine BUT when the user tries to press the enabled false datagridview couple of times, the main thread becomes unresponsive and the progressbar freezes.
Can anyone guide me how to deal with it?
You are running the whole code using Invoke. It means you are switching to UI thread and the code is running in UI thread. Since the code is a time-consuming for loop, then it's blocking UI thread.
Instead of using a BackgroundWorker, to format cells, it's better to use CellFormatting event:
private void dgv_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
{
//If this is header cell or new row, do nothing
if (e.RowIndex < 0 || e.ColumnIndex < 0 || e.RowIndex == dgv.NewRowIndex)
return;
//If formatting your desired column, perform validation
if (e.ColumnIndex == dgv.Columns["Name"].Index)
{
// Perform validation and change cell back color here.
}
}
Maybe try to disable the Button when it get clicked until the job done?.
Lets say your Button name is Button1,
when the user click on the Enabled false data grid view, use Button.enabled=false, then when the job is done use Button.enabled=true
hope that helps!

Wrong results when trying to get sizes of a pane with css-formattings

I came across a strange behaviour of JavaFX when i tried to obtain the bordersizes (bounds) of a pane that has some css-effects//formattings applied to it. In my application i have to lookup the exact sizes of different objects in order to connect them with lines (imagine some sort of UML-diagramm editor, the start and endpoints of the lines are the border coordinates of the objects).
Now to my problem: whenever i try to get the bordersizes of an object in the same method where this object is put on the scene graph, the result does not include any css attributes like padding, bordersize, strokes and so on. The exact result gets returned if the object already exists on the scene graph before i lookup the size. It seems to be that JavaFX has to wait for one rendering pass (16,7ms) to actually update the real bounds and sizes on an object. Is there any way to get the size of an object (especially those which extend Pane) in the same method as it is created? I don't really like the workaround with waiting for 16,7ms, because it creates some unwanted behaviour in my application.
The following code shows the problem. The size when creating the pane containing the rectangle does not equal the size when pressing the "show size" button.
public class SzenarioView extends GridPane
{
private Group paintingLayer;
public SzenarioView()
{
super();
paintingLayer = new Group();
paintingLayer.getStylesheets().add(TestStarter.class.getResource("ReprBox.css").toString());
Rectangle r1 = new Rectangle(0, 0, 1000, 1000);
r1.setFill(Color.AZURE);
paintingLayer.getChildren().add(r1);
Button b1 = new Button("Show Size");
b1.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
for(Node n : paintingLayer.getChildren())
{
System.out.println("Border...");
System.out.println(getNodeBorderCoords(n, BorderTypes.RIGHT)[0]);
System.out.println(getNodeBorderCoords(n, BorderTypes.RIGHT)[1]);
System.out.println("End Border");
}
}
});
Button b2 = new Button("Add CCSBTN");
b2.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
BorderPane bp = new BorderPane();
bp.getStylesheets().add(TestStarter.class.getResource("ReprBox.css").toString());
Rectangle rcss = new Rectangle(50, 50);
bp.setTop(rcss);
bp.getStyleClass().add("my-box");
setObjectOnScreen(bp, 100, 100);
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[0]);
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[1]);
}
});
this.add(b1, 0, 0);
this.add(b2, 1, 0);
this.add(paintingLayer, 1, 1);
this.setMaxHeight(500);
this.setMaxWidth(700);
this.setHgap(10);
this.setVgap(10);
this.setPadding(new Insets(10, 10, 10, 10));
}
public void setObjectOnScreen(Node obj, double toX, double toY)
{
obj.setLayoutX(toX);
obj.setLayoutY(toY);
paintingLayer.getChildren().add(obj);
}
public double[] getNodeBorderCoords(Node n, BorderTypes type)
{
double x = 0;
double y = 0;
double bx = n.getBoundsInLocal().getWidth();
double by = n.getBoundsInLocal().getHeight();
switch (type)
{
case LEFT:
x = n.getLayoutX();
y = n.getLayoutY() + by / 2;
break;
case RIGHT:
x = n.getLayoutX() + bx ;
y = n.getLayoutY() + by / 2;
break;
case TOP:
x = n.getLayoutX() + bx / 2;
y = n.getLayoutY();
break;
case BOTTOM:
x = n.getLayoutX() + bx / 2;
y = n.getLayoutY() + by;
break;
}
double[] ret =
{ x, y, };
return ret;
}
}
The CSS-File
#CHARSET "ISO-8859-1";
.my-box {
-fx-border-color: rgb(255, 0, 0);
-fx-border-radius: 2;
-fx-padding: 1 1 1 1;
-fx-border-width: 5 5 5 5;
}
By the way, it doesn't matter if use getBoundsInLocal() or getBoundsInParent() .
UPDATE
Here are two workarounds that can be used:
Thread t = new Thread(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(17);
} catch (InterruptedException e) {
e.printStackTrace();
}
Platform.runLater(new Runnable() {
#Override
public void run() {
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[0]);
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[1]);
}
});
}
});
t.start();
But delaying the call might cause some strange behaviour like i stated in my post. But i found another "solution" recently.
bp.snapshot(new SnapshotParameters(), new WritableImage(5, 5));
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[0]);
System.out.println(getNodeBorderCoords(bp, BorderTypes.RIGHT)[1]);
The snapshot() method applies all css effects (and all other layout work) on the node. After that, the returned values of the borders are correct.
There are 2 approaches:
You can use binding instead of static size call. It gives benefits of additional support for update after resize but adds a bit of listeners handling burden on FX enging.
Wrapping size reading logic into Platform.runLater() will put it later into event queue and should address premature size access issue.

One JTextField stores and updates text, the other doesn't

So, I made a class that takes arrays and calculates a value from them. I then decided (unknowingly) to incorporate it into a GUI interface. All went well until I noticed this strange error; one of the jtextfields (prarie) would not store text while the other (yard) does.
I looked around and found my problem similiar to mine on this site;
Updating text in a JTextField
But he had one that doesn't work at all, where I have one that works and one that doesn't.
The Code is here (it's a bit long, but most of it is GUI), so hold your breath!:
import java.awt.GridLayout;
import javax.swing.Box;
import javax.swing.JCheckBox;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Window {
/**
* #param args
*/
private static int numb;
private static double micro, centi;
private static JTextField[] yard,prarie;
private static double[] charges,distances;
public static void main(String[] args)
{
//create a small dialog window to take in number of charged objects
JPanel startup = new JPanel();
JTextField many = new JTextField(5);
startup.add(many);
int result = JOptionPane.showConfirmDialog(null,startup , "Please Enter How Many Charged Objects are Being Evaluated", JOptionPane.OK_CANCEL_OPTION);
many.requestFocusInWindow();
//once ok is clicked, then the number input will be stored under 'numb'
//then proceed to inputFields
if (result == JOptionPane.OK_OPTION)
{
numb = Integer.parseInt(many.getText());
inputFields();
}
}
//this window opens the various JTextFields for input
public static void inputFields()
{
//top JTextFields
yard = new JTextField[numb];
JPanel chargePanel = new JPanel();
for(int x=0;x<numb;x++)
{
yard[x] =new JTextField(5);
chargePanel.add(new JLabel("Charge "+ Integer.toString(x+1)+":"));
chargePanel.add(yard[x]);
chargePanel.add(Box.createVerticalStrut(15)); // a spacer
}
//bottom JTextFields
prarie = new JTextField[numb-1];
JPanel meterPanel = new JPanel();
for(int x=0;x<numb-1;x++)
{
prarie[x]=new JTextField(5);
meterPanel.add(new JLabel("Meters "+ Integer.toString(x+1)+":"));
meterPanel.add(new JTextField(5));
meterPanel.add(Box.createVerticalStrut(15)); // a spacer
}
//JCheckBoxes
JCheckBox isMicro = new JCheckBox("Charges are in terms of microCoulombs");
JCheckBox isCm = new JCheckBox("Distances are in terms of centiMeters");
JPanel chechBox = new JPanel();
chechBox.add(isMicro);
chechBox.add(Box.createVerticalStrut(20));
chechBox.add(isCm);
//Paste them all together into one window
GridLayout gufi = new GridLayout(3,1);
JPanel host = new JPanel(gufi);
host.add(chargePanel);
host.add(meterPanel);
host.add(chechBox);
int result1 = JOptionPane.showConfirmDialog(null, host, "Please Enter Charge and Distance Values", JOptionPane.OK_CANCEL_OPTION);
//if ok is clicked, then go to 'printArr()' to print the JTextFields
//then go to assign the values from the JTextFields to private double arrays 'yard' and 'prarie'
if (result1 == JOptionPane.OK_OPTION)
{
micro = (isMicro.isSelected())? Math.pow(10, -6): 1;
centi = (isCm.isSelected())? .01: 1;
printArr();
assign();
}
}
//a makeshift method to print the value from the JTextFields
//to fix the problem of why prarie wouldn't store numbers
public static void printArr()
{
System.out.println("Charges are:");
for(int x=0;x<numb;x++)
System.out.print(yard[x].getText() + " ");
System.out.println("Distances are:");
for(int x=0;x<numb-1;x++)
System.out.print(prarie[x].getText() + " ");
}
//assigns values from JTextFields to the private double arrays 'yard' and 'prarie'
public static void assign()
{
try {
charges = new double[numb];
for(int x=0;x<numb;x++)
charges[x]=micro*Double.parseDouble(yard[x].getText().trim());
distances = new double[numb-1];
for(int x=0;x<numb-1;x++)
distances[x]=centi*Double.parseDouble(prarie[x].getText().trim());
} catch (NumberFormatException e) {
e.printStackTrace();
//inputFields();
}
calculate();
}
public static void calculate()
{
JPanel sample = new JPanel();
JTextField whichOne = new JTextField(5);
sample.add(whichOne);
int result = JOptionPane.showConfirmDialog(null,sample , "Please Enter Which Charged Object thy Wishs For", JOptionPane.OK_CANCEL_OPTION);
whichOne.requestFocusInWindow();
if (result == JOptionPane.OK_OPTION)
{
int target = Integer.parseInt(whichOne.getText());
}
}
}
Anyone who runs the code and takes the time to enter dummy values will see that 'yard' stores values while 'prarie' does not. Why is this?
*I'm pretty sure I'm overlooking obvious (as always).
Change:
meterPanel.add(new JTextField(5));
to:
meterPanel.add(prarie[x]);
in the for loop for the prarie textfields

Change Session/ViewState on buttonclick

me again,
I have a current page containing a usercontrol which lists buildings.
Here is a screenshot: http://i40.tinypic.com/2eusoyt.png
Now, my mentor asked me to build a button which allows the user the make the page show the properties in 2 columns.
How did I try this?
I tried putting the following in my Page_load:
if (ViewState["numberOfColumns"] != null)
{
numberOfColumns= Int32.Parse(ViewState["numberOfColumns"].ToString());
}
else
{
ViewState["numberOfColumns"] = 1;
numberOfColumns= 1;
}
Then behind the button view I put this code:
protected void btnView_Click(object sender, EventArgs e)
{
switch(numberOfColumns)
{
case 1:
numberOfColumns= 2;
ViewState["numberOfColumns"] = numberOfColumns;
break;
case 2:
numberOfColumns= 1;
ViewState["numberOfColumns"] = numberOfColumns;
break;
}
}
But as I guessed this method needs one postback to set the sessionvariable, and another one to execute the pageload with the latest value.
I know there should be "a proper way" of doing this, but I can't find it.
Any direct you guys could point me would be greatly appreciated.
Thanks in advance, Christophe
Okay,
This is how I did it.
The method building the output of the user control was called directly after the snippet above. It's called "GetProperties()".
So the problem was/is that according to the page cycle, .net first executes the Page_Load, and as last the control events.
So what I did was put the call to getProperties() for the first time (when IsPostback = false) in an if. So when you visit the page once, it will load the method, and after that no longer.
So, then I put the methodcall in my button, because when you click the button IsPostback = true.
This worked. Snippets below:
protected void Page_Load(object sender, EventArgs e)
{
//some generic stuff
if (!IsPostBack)
{
ViewState["kolommen"] = 1;
AantalKolommen = 1;
GetProperties(_tkth, _categorie, _verkochtverhuurd);
}
}
And behind the button I did the following:
protected void btnView_Click(object sender, EventArgs e)
{
switch (Int32.Parse(ViewState["kolommen"].ToString()))
{
case 1:
AantalKolommen = 2;
ViewState["kolommen"] = 2;
break;
case 2:
AantalKolommen = 1;
ViewState["kolommen"] = 1;
break;
}
GetProperties(_tkth, _categorie, _verkochtverhuurd);
}
This works like a charm. Altho, I'd still like to know if this

How to make void other thread visit until the code block finished for windows phone animation

I am making a top notification animation, but I don't know how to make the animation synchronous until the animation finishes. Here is the code I have:
public Storyboard prepareShowStory(int count, NotificationControl notifyControl)
{
notifyControl.textBlock1.Text = "Got" + count.ToString() + "Message";
notifyControl.RenderTransform = new CompositeTransform();
Storyboard story = new Storyboard();
//From here until the annimation finish and remove LayoutRoot.Resources.Clear();
LayoutRoot.Resources.Add("unique_id", story);
story.Completed += (object sender, EventArgs e) =>
{
story.Stop();
story.Children.Clear();
App.ViewModel.myAction -= CompletedRefresh;
LayoutRoot.Resources.Clear();
//To here.
};
story.Begin();
DoubleAnimation animation;
animation = new DoubleAnimation();
animation.AutoReverse = true;
animation.From = -64;
animation.To = 60;
animation.Duration = new Duration(TimeSpan.FromMilliseconds(1600));
animation.EasingFunction = _EasingFunction;
Storyboard.SetTargetName(animation, notifyControl.Name);
Storyboard.SetTargetProperty(animation, new PropertyPath("(UIElement.RenderTransform).(CompositeTransform.TranslateY)"));
story.Children.Add(animation);
return story;
}
You could check the ResourceDictionary before adding to it.
if(!LayoutRoot.Resources.Contains("unique_id"))
LayoutRoot.Resources.Add("unique_id", story);

Resources