I have written a function AddItem that adds an item to a listview. I also have created a function to create dynamic buttons. But once i create a dynamic button i would like it to have the AddItem function work when the button is pressed.
I have no clue how i would solve this because im relatively new to C# and windows forms.
private void AddButton(string Name, string Text, int Posx, int Posy, double Price, string ItemName)
{
// Create a Button object
Button NewButton = new Button();
// Set Button properties
NewButton.Height = 50;
NewButton.Width = 120;
NewButton.BackColor = Color.Gainsboro;
NewButton.ForeColor = Color.Black;
NewButton.Location = new Point(Posx, Posy);
NewButton.Text = Text;
NewButton.Name = Name;
NewButton.Font = new Font("Microsoft Sans Serif", 12);
// Add a Button Click Event handler
NewButton.Click += new EventHandler(NewButton_Click);
//Add to form ontop of panelButtonHamburgers
panelButtonsHamburgers.Controls.Add(NewButton);
}
private void NewButton_Click(object sender, EventArgs e)
{
AddItem(Price, ItemName);
}
As you can see the AddButton function takes a price and itemname, once the button is clicked i would like the additem function to run with this same price and itemname.
Thanks!
As far as I understood, you need a hanlder that uses some specific values for each dynamic button. There are few approaches you can use.
Use Tag property and save values in some format
newBut.Tag = $"{Price},{ItemName}";
and than, in handler
//always check for null
Button button = sender as Button;
string data = button.Tag as string;
//do staff with your data
Create Dictionary and every time you add new button add it as a key to Dictionary and that, in handler get your data (but this is one of the worst way to do it, so try to avoid it);
Use "Command" pattern. Make a special class for executing your operation. It should look like this
class MyCommand
{
public double Price { get; set; }
public string Name { get; set; }
public ListView List { get; set; } //here is the list you want to add item to.
public void Handle (object sender, EventArgs e)
{
//Do your staff here
}
}
It is a little bit tricky but introduces good pattern you can use in future.
You could assign a tuple to the button's Tag.
private void AddButton(string Name, string Text, int Posx, int Posy, double Price, string ItemName)
{
...
NewButton.Tag = (Price, ItemName);
}
Then you can the get that tuple's values from the sender in the event, which actually is the button.
private void NewButton_Click(object sender, EventArgs e)
{
double price = (((double Price, string ItemName))((Button)sender).Tag).Price;
string itemName = (((double Price, string ItemName))((Button)sender).Tag).ItemName;
...
}
Related
I am working on a WinForms application where I want the user to click a button and then change the button's text (add +1 to the counter). I have multiple buttons and having three methods Click MouseDown and MouseUp for each of those would be pretty inefficient.
So I've set up a class, but don't know how to assign it to all the buttons.
public class AddButton : Button
{
public int Count { get; set; }
private void Button_Click(object sender, EventArgs e)
{
AddButton ab = (AddButton)sender;
Count++;
ab.Text = Count + " Added";
}
}
Maybe I could also just link all the button's EventHandlers to one, but I don't know how to start there and where to put the code. Here is the Visual Studio project download link if you need it.
You could try this code:
public class AddButton:Button
{
public int Count { get; set; } = 0;
public AddButton()
{
// After it's painted, set its text to current Counter
this.Paint += (s, e) => this.Text = Count.ToString();
this.Click += (s, e) => this.Text = (++Count).ToString();
}
}
In your project it's enough to change buttons initialization from:
Button button1 = new Button();
to
Button button1 = new AddButton();
// or
AddButton button1 = new AddButton();
I´m using WindowsForm and working with flat design. In the program there are 6 buttons, these buttons are made of a label and a panel. The label controls all the actions that the button can do. when i started writing the program i made one function for each button, now i like to use one function that controls all buttons. I have tried to make that work but I´m stuck and can´t find a way to solve it.
Been looking around at the forum for solutions but i think that i might not know what i´m looking for.
This is what i made so far.
Buttons[] cobra = new Buttons[5];
private class Buttons
{
private bool position;
private string name;
public bool Position
{
get { return position; }
set { position = value; }
}
public string Name
{
get { return name; }
set { name = value; }
}
}
private void SetButtons()
{
cobra[0].Name = "label3";
cobra[0].Position = false;
cobra[1].Name = "label4";
cobra[1].Position = false;
}
private void CheckStatusButtons(object import)
{
for (int i = 0; i < cobra.Length; i++)
{
}
}
private class ToggelFunction
{
private bool hawk;
public bool Hawk
{
get { return hawk; }
set { hawk = value; }
}
}
ToggelFunction tiger = new ToggelFunction();
private void label3_Click(object sender, EventArgs e)
{
if (tiger.Hawk == false)
{
button1.BackColor = Color.PaleGreen;
label3.Text = "ON";
if (myport.IsOpen)
{
send(new byte[] { 16, 128, 32, 16, 1 });
}
tiger.Hawk = true;
return;
}
if (tiger.Hawk == true)
{
button1.BackColor = Color.DarkSeaGreen;
label3.Text = "2";
if (myport.IsOpen)
{
send(new byte[] { 16, 128, 32, 8, 1 });
}
tiger.Hawk = false;
return;
}
}
"label3_Click" this is my function for button 1, all buttons look the same just different variables.
As I found on the forum, you can use object sender to i identify which button that made the click and from there use that in the function to make action.
So all buttons will use this functions, i´m not sure how to compare values in the if statement, if button 1 is click then it should check what values button 1 has.
My idea was to make a class "Buttons" and an array to store all the values of each button, it´s not completed yet. When a button is clicked it checks
with the array what values that button has and compare that in the function depending on what the action is. The first action would be to check if the button is on or off. If it´s off then it enters that if statement and there some actions will happen, change of color and the text, these values also have to be stored in the array i guess.
I have tried to compare the array with object sender, but i get some error saying that you can´t compare bool with object i think.
So i wonder if some one might have a solution or suggestions?
I have made a simple example of what i think you want to do. bare in mind this does not abide by all coding best practises but its not a mess either. You will need to put your safety null checks in.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public class ButtonVariables
{
public int value1 { get; set; }
public int value2 { get; set; }
}
Dictionary<string, ButtonVariables> bv = new Dictionary<string, ButtonVariables>();
private void ProcessClick(object sender, EventArgs e)
{
ButtonVariables vars = GetVariables(sender);
//Do stuff with your variable set here
}
private ButtonVariables GetVariables(object sender)
{
ButtonVariables returnValue = new ButtonVariables();
switch (((Button)sender).Name.ToLower())
{
case "buttona":
return bv["A"];
case "buttonb":
return bv["B"];
case "buttonc":
return bv["C"];
default:
break;
}
return null;
}
private void ButtonA_Click(object sender, EventArgs e)
{
ProcessClick(sender, e);
}
private void ButtonB_Click(object sender, EventArgs e)
{
ProcessClick(sender, e);
}
private void ButtonC_Click(object sender, EventArgs e)
{
ProcessClick(sender, e);
}
}
I've basically added two methods to handle your method. One to identify the button and get its related values from a dictionary that you will have to populate with your Buttons class. and one to carry out the logic.
EDIT
As requested in the comments here's an easy (but not the only way) to point your event listeners towards the same method.
Initially you need to set up with one button and double click it or do some other way to create the forms Button_Click() Event Method. At this point an event listener delegate has been added to your Form.Designer.cs File. Open that file and you will see something like this:
//
// ButtonA
//
this.ButtonA.Location = new System.Drawing.Point(12, 12);
this.ButtonA.Name = "ButtonA";
this.ButtonA.Size = new System.Drawing.Size(75, 23);
this.ButtonA.TabIndex = 0;
this.ButtonA.Text = "button1";
this.ButtonA.UseVisualStyleBackColor = true;
this.ButtonA.Click += new System.EventHandler(this.ButtonA_Click);
What you need to do is create your other buttons and add this code in for them with a change to the last line new System.EventHandler(this.ButtonA_Click); This line basically states which method to call when the ButtonA.Click event is invoked. At this point you can add what ever method you want (as long as you name is nicely for good convention). So your example would be this :
//
// ButtonA
//
this.ButtonA.Location = new System.Drawing.Point(12, 12);
this.ButtonA.Name = "ButtonA";
this.ButtonA.Size = new System.Drawing.Size(75, 23);
this.ButtonA.TabIndex = 0;
this.ButtonA.Text = "button1";
this.ButtonA.UseVisualStyleBackColor = true;
this.ButtonA.Click += new System.EventHandler(this.ProcessClick);
//
// ButtonB
//
this.ButtonB.Location = new System.Drawing.Point(12, 12);
this.ButtonB.Name = "ButtonB";
this.ButtonB.Size = new System.Drawing.Size(75, 23);
this.ButtonB.TabIndex = 0;
this.ButtonB.Text = "B";
this.ButtonB.UseVisualStyleBackColor = true;
this.ButtonB.Click += new System.EventHandler(this.ProcessClick);
//
// ButtonC
//
this.ButtonC.Location = new System.Drawing.Point(12, 12);
this.ButtonC.Name = "ButtonC";
this.ButtonC.Size = new System.Drawing.Size(75, 23);
this.ButtonC.TabIndex = 0;
this.ButtonC.Text = "C";
this.ButtonC.UseVisualStyleBackColor = true;
this.ButtonC.Click += new System.EventHandler(this.ProcessClick);
Remember you need to physically create the buttons on the form itself.
Lets say you have three labels and a panel for each label. You can add the event handler to all of them and whenever that event fires the event handler will use that label as the sender. To keep the panel associated with the label, you could add the panel to the label's tag property. Then, in the event handler you can then get the panel from the label.
label1.Click += label_Click;
label2.Click += label_Click;
label3.Click += label_Click;
label1.Tag = panel1;
label2.Tag = panel2;
label3.Tag = panel3;
In the event handler, just cast sender to Label and there you have your label object to do whatever you want with and like I said, the panel is in the Tag property. I did a little refactoring to your code to make it cleaner looking.
private void label_Click(object sender, EventArgs e)
{
// this is what itsme86 was suggesting in the comments
var label = (Label)sender;
var panel = (Panel)label.Tag;
label.BackColor = tiger.Hawk ? Color.DarkSeaGreen : Color.PaleGreen;
label.Text = tiger.Hawk ? "2" : "ON";
if (myport.IsOpen)
send(new byte[] { 16, 128, 32, 8, 1 });
tiger.Hawk = !tiger.Hawk;
}
Let me know if you have any questions about this.
So I was trying to send custom arguments to an event, but it never worked, I tried so many different methods, but I never got it to work,
So basically!
public void CreateEmojiList()
{
CreateAllEmojis();
int btnCount = 0;
foreach(Emoji emoji in emojiList)
{
Button btnEmoji = new Button();
btnEmoji.Size = new Size(40, 36);
btnEmoji.FlatStyle = FlatStyle.Flat;
btnEmoji.FlatAppearance.MouseDownBackColor = Color.Cyan;
btnEmoji.Cursor = Cursors.Hand;
btnEmoji.Font = new Font("Bahnschrift", 6.75f);
btnEmoji.Text = emoji.EmojiText;
btnEmoji.Top = (panel_main.Controls.OfType<Button>().Count<Button>() / 4) * (1 + btnEmoji.Height) + 6;
btnEmoji.Left = (btnEmoji.Width + 1) * btnCount + 6;
panel_main.Controls.Add(btnEmoji);
btnEmoji.Click += //What do I do here?
; btnCount++;
if (btnCount == 4)
btnCount = 0;
}
}
protected virtual void OnEmojiClick(EmojiClickEventArgs e)
{
if (this.EmojiClick != null)
EmojiClick(e);
}
this is the class I want to use to pass my arguments:
public class EmojiClickEventArgs : EventArgs
{
private string emojiText;
private string emojiName;
public EmojiClickEventArgs(string EmojiText, string EmojiName)
{
this.EmojiText = EmojiText;
this.EmojiName = EmojiName;
}
public string EmojiText { get { return emojiText; } set { emojiText = value; } }
public string EmojiName { get { return emojiName; } set { emojiName = value; } }
}
I want to get those two values from
emoji.EmojiText and emoji.EmojiName
You can take advantage of closures to "package up" the additional event data for each button's event handler. Just make sure not to close over the loop variable.
public void CreateEmojiList()
{
CreateAllEmojis();
int btnCount = 0;
foreach(Emoji emoji in emojiList)
{
Button btnEmoji = new Button();
btnEmoji.Size = new Size(40, 36);
btnEmoji.FlatStyle = FlatStyle.Flat;
btnEmoji.FlatAppearance.MouseDownBackColor = Color.Cyan;
btnEmoji.Cursor = Cursors.Hand;
btnEmoji.Font = new Font("Bahnschrift", 6.75f);
btnEmoji.Text = emoji.EmojiText;
btnEmoji.Top = (panel_main.Controls.OfType<Button>().Count<Button>() / 4) * (1 + btnEmoji.Height) + 6;
btnEmoji.Left = (btnEmoji.Width + 1) * btnCount + 6;
panel_main.Controls.Add(btnEmoji);
var emojiCopy = emoji; //don't close on the loop variable!
btnEmoji.Click += (sender,args) => OnEmojiClick(emojiCopy);
btnCount++;
if (btnCount == 4)
btnCount = 0;
}
}
protected virtual void OnEmojiClick(Emoji emoji)
{
//do something
}
One way is to inherit from Button and create a class called EmojiButton. You then declare a delegate that matches the signature of the your event handler. After that, declare an event using the delegate in the EmojiButton class, add property like EmojiText and EmojiName to the button subclass as well. Finally you need to link the button click event with your custom event. Whenever the button is clicked, raise your event and pass your arguments i.e. this.EmojiText, this.EmojiName.
Another way is to assign your Emoji objects to the Tag property. You can then write the event handler with the normal EventHandler signature (object sender, EventArgs e), and look at what the sender's Tag is. You then cast the Tag to an Emoji and access its properties.
The fastest solution that comes to my mind and that doesn't imply the definition of custom UserControl classes, the subclassing of Button and other similar practices is:
btnEmoji.Click += (sender, e) =>
{
Button b = (Button)sender;
// let's suppose that the button name corresponds to the emoji name
String emojiName = b.Name;
// let's suppose that the button tag contains the emoji text
String emojiText = (String)b.Tag;
Emoji_Clicked(sender, e, (new EmojiClickEventArgs(emojiText, emojiName)));
};
private void Emoji_Clicked(Object sender, EventArgs e, EmojiClickEventArgs ee)
{
// Your code...
}
First and foremost thing you need to define delegate ,then create an instance.
class Emojis
{
// public delegate void EmojiClickEventHandler(object sender,EventArgs args);
//public event EmojiEventHandler EmojiClicked;
//you can use above two lines or replace them instead below code.
public event EventHandler<EmojiClickEventArgs> EmojiClicked;
public void CreateEmojiList()
{
CreateAllEmojis();
int btnCount = 0;
//rest of the code
panel_main.Controls.Add(btnEmoji);
btnEmoji.Click += OnEmojiClick(btnEmoji);
btnCount++;
}
protected virtual void OnEmojiClick(Button emoji)
{
//Here null check to handle if no subscribers for the event
if(EmojiClicked!=null)
{
//there is no name property define for emoji but only text hence passing only text.
EmojiClicked(this ,new EmojiClickEventArgs(emoji.Text,emoji.Text){ });
}
}
private void Emoji_Clicked(Object sender, EmojiClickEventArgs args)
{
Button mybutton = sender as Button;
Console.WriteLine("emoji text "+ args.Text);
}
}
So the rest of the code is working fine but when it gets to the part where you have to select from predetermined values from the drop down menu, it doesn't display my options but instead allows the user to choose their own.
namespace A2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
comboBox1.Items.Add("15%");
comboBox1.Items.Add("18%");
comboBox1.Items.Add("20%");
}
private void button1_Click(object sender, EventArgs e)
{
double amount, tax, tip, total, final;
amount = double.Parse(textBox1.Text);
tax = amount * 0.1;
labelTax.Text = tax.ToString();
total = amount + tax;
labelTotal.Text = total.ToString();
tip = amount * double.Parse(comboBox1.Text);
labelTip.Text = tip.ToString();
final = amount + tip + tax;
labelFinal.Text = final.ToString();
}
}
}
The SelectedIndexChanged event is fired when the user changes a selection in the combo box. With your code above, any time they choose a new item, you're adding 3 more.
However, as it stands now, the combo box is empty when the form loads, so this event will never fire (there are no choices to select). And then, as you mention, the user can type something in themselves.
To fix this, you might want to move that code into the Form_Load event instead. This way, the combo box will have the items added from the start. You also might want to set the DropDownStyle to DropDownList, which will prevent the user from being able to type in the combo box. And then you can set the SelectedIndex to 0 so the first item is selected:
private void Form1_Load(object sender, EventArgs e)
{
comboBox1.Items.Add("15%");
comboBox1.Items.Add("18%");
comboBox1.Items.Add("20%");
comboBox1.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox1.SelectedIndex = 0;
}
Another problem you will run into is having the percent sign as part of the comboBox item text. double.Parse() will not know what to do with this. In order to resolve this, you can use the string.Replace() method to replace the percent character with an empty string before parsing as a double.
Additionally, you will want to divide this whole number by 100 so it's treated as a percentage:
tip = amount * (double.Parse(comboBox1.Text.Replace("%", "")) / 100);
Another approach to use data-binding and have strong typed values.
Use decimal as type for money related calculations
public class Tax
{
public decimal Value { get; }
public string Text { get => Value.ToString("0.## '%'"); }
public Tax(decimal value)
{
Value = value;
}
}
private void Form1_Load(object sender, EventArgs e)
{
var taxes = new[]
{
new Tax(15),
new Tax(18),
new Tax(20),
}
comboBox1.ValueMember = "Value";
comboBox1.DisplayMember = "Text";
comboBox1.DataSource = taxes;
comboBox1.DropDownStyle = ComboBoxStyle.DropDownList;
comboBox1.SelectedValue = 15;
}
Then in button click you can access selected value
var selectedTax = (decimal)combobox.SelectedValue;
or you can get whole selected object
var selectedTax = (Tax)combobox.SelectedItem;
I am creating a 2d array of buttons using code and I want to add a button_click() method.
Besides the 2 usual arguments (object sender, EventArgs e) I want to get as an input 2 more variables, To identify which button was clicked, and do something else as a result.
I am currently doing this
arr[i,j].Click+= new EventHandler(button_click);
public void button_click(object sender, EventArgs e)
Is there another way of adding events that will allow me to do what I want?
And on a seperate note. Is there an easy way of creating cubes with a certain color without using buttons?
To identify which button was clicked, and do something else as a result.
You could use sender parameter to identify the button which was clicked.
If you do not want to introduce a custom button type which would have properties for i and j, you could use Tag property to store the indices.
Create a class which inherits from button class. And add 2 properties to it. Then access those properties in your form . Following example is one way to solve your problem.
public class ButtonCtrl : Button
{
public ButtonCtrl(int _arg1, int _arg2)
{
Arg1 = _arg1;
Arg2 = _arg2;
}
public int Arg1 { get; set; }
public int Arg2 { get; set; }
}
//create buttons in form c'tor
public Form1()
{
InitializeComponent();
ButtonCtrl button1 = new ButtonCtrl(1,2);
button1.Text = "dynamic 1";
button1.Click += new EventHandler(button_click);
button1.Top = 10;
this.Controls.Add(button1);
ButtonCtrl button2 = new ButtonCtrl(3, 4);
button2.Text = "dynamic 2";
button2.Click += new EventHandler(button_click);
button2.Top = 30;
this.Controls.Add(button2);
}
And the event handler
public void button_click(object sender,EventArgs e)
{
if(sender is ButtonCtrl)
{
ButtonCtrl btnCtrl= sender as ButtonCtrl;
label1.Text = btnCtrl.Arg1.ToString() + " " + btnCtrl.Arg2.ToString();
}
}