I have two UserControls: Player and Playlist.
Player.cs
namespace Music_Player
{
public partial class Player : UserControl
{
public int currentSongIndex = 0;
public WindowsMediaPlayer player = new WindowsMediaPlayer();
public Player()
{
InitializeComponent();
player.settings.autoStart = false;
}
private void playButton_Click(object sender, EventArgs e)
{
if (playButton.Text == "Play")
{
Play();
}
else
{
Pause();
}
}
public void Play()
{
if (CheckSongs()) { return; }
playButton.Text = "Pause";
player.controls.play();
}
...
Playlist.cs
namespace Music_Player
{
public partial class Playlist : UserControl
{
public Playlist()
{
InitializeComponent();
}
private void playlistTitle_Click(object sender, EventArgs e)
{
player.Play(); // THIS IS WHERE I WANT TO USE THE player INSTANCE OF Player()
}
...
The UserControls are both children of another UC which is in my Form.
How can I use the player which is an instance of Player() inside Playlist?
Suppose you have added a player1 and a playList1 to the form.
To call the method in another UserControl, you can define a property in Form.cs to access the player1 instance.
public Player PlayerInstance
{
get { return player1; }
}
Then you can call Player.Play() in Playlist.cs via the code as followed.
private void playlistTitle_Click(object sender, EventArgs e)
{
Form1 form1 = (Form1)this.FindForm();
form1.PlayerInstance.Play();
}
You probably want to handle events in the form the controls are in, not within the control itself. The form would have a reference to both controls and likely whatever they are controlling. That's where things should be connected.
Related
I have a "MainForm" and a "GraphicsForm". Clicking "New" on the main form, a "GraphicsForm" will be created.
The problem is that when I create multiple "GraphicsForm", and when I want to save the content of one of the "GraphicsForm", I need to clicking "Save" on the "MainForm" and the program will save the content of the active "GraphicsForm" to a file, I don't know how to pass the content of this "GraphicsForm" to "MainForm" for storage.
MainForm.cs
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
private ToolStripMenuItem _winMenuItem = new ToolStripMenuItem();
private GraphicsForm _graphicsForm;
private int _counter = 1;
private void New_Click(objec sender, EventArgs e)
{
_winMenuItem.Name = "Win";
_winMenuItem.Text = "Windows";
int item = MainMenuStrip.Items.IndexOf(_winMenuItem);
if (item == -1)
{
MainMenuStrip.Items.Add(_winMenuItem);
MainMenuStrip.MdiWindowListItem = _winMenuItem;
}
_graphicsForm = new GraphicsForm();
_graphicsForm.Name = string.Concat("Win_", _counter.ToString());
_graphicsForm.Text = _graphicsForm.Name;
_graphicsForm.MdiParent = this;
_graphicsForm.Show();
_graphicsForm.WindowState = FormWindowState.Maximized;
_counter++;
}
private void Save_Click(object sender, EventArgs e)
{
... // Problem here
}
private void Open_Click(object sender, EventArgs e)
{
... // Problem here
}
}
GraphicsForm.cs
public partial class GraphicsForm : Form
{
//StorageDoc is a class to manage all the graphics drawn by the user in the form.
private StorageDoc _storageDoc = new StotageDoc();
public GraphicsForm()
{
InitializeComponent();
}
private Canvas_MouseDown()
{
}
private Canvas_Paint()
{
}
...
Because MainForm is a MDI form, it is easy to use ActiveMdiChild to get the active child form.
class MainForm : Form
{
public void OnSaveButtonClick(object sender, EventArgs e)
{
if(ActiveMdiChild is GraphicsForm g)
Save(g);
}
}
I'm sure this has been answered before but basically, you pass in an instance of the 'data storage' to the new form.
interface ISaveForm
{
void Save();
}
class MainForm
{
private DataStorage _dataStorage;
private ICollection<ISaveForm> _forms = new List<ISaveForm>();
public void OnNew()
{
var subForm = new GraphicsForm(_dataStorage);
subForm.Show();
_forms.Add(subForm);
}
public void OnSave()
{
foreach(var form in _forms)
{
form.Save();
}
}
}
class GraphicsForm : Form,ISaveForm
{
private DataStorage _dataStorage;
public GraphicsForm(DataStorage dataStorage)
{
_dataStorage = dataStorage;
}
public void Save()
{
}
}
I have a problem with displaying UserControl on my Form.
The program in the nutshell:
In Form1 I have a button. After clicking this, in the Panel (container) my first UserControl (new.cs) are dynamically loaded.
On that panel I have another button that leads to another UserControl (choice.cs) and I want to display it in the same Panel (container) on my Form1.
The first point works good, but I have a problem with second one. I think I have to correct choice_button_Click function. Is there an easy way to do it?
Here is my code:
Form1.cs:
namespace WindowsFormsApp1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void new_button_Click(object sender, EventArgs e)
{
if (!container.Controls.Contains(#new.Instance))
{
container.Controls.Add(#new.Instance);
#new.Instance.Dock = DockStyle.Fill;
#new.Instance.BringToFront();
}
else
{
#new.Instance.BringToFront();
}
}
public Panel getContainer()
{
return container;
}
}
}
new.cs:
namespace WindowsFormsApp1
{
public partial class #new : UserControl
{
private static #new _instance;
public static #new Instance
{
get
{
if (_instance == null)
_instance = new #new();
return _instance;
}
}
public #new()
{
InitializeComponent();
}
private void choice_button_Click(object sender, EventArgs e)
{
using (Form1 main = new Form1())
{
if (!main.getContainer().Controls.Contains(choice.Instance))
{
main.getContainer().Controls.Add(choice.Instance);
choice.Instance.Dock = DockStyle.Fill;
choice.Instance.BringToFront();
}
else
{
choice.Instance.BringToFront();
}
}
}
}
}
choice.cs:
namespace WindowsFormsApp1
{
public partial class choice : UserControl
{
private static choice _instance;
public static choice Instance
{
get
{
if (_instance == null)
_instance = new choice();
return _instance;
}
}
public choice()
{
InitializeComponent();
}
}
}
Your functional problem is that you aren't placing choice.Instance inside your instance of your Form1. You are creating a new form instead, placing it there, then discarding that form.
However, you also have an issue in your design, where you are violating the principal wherein a UserControl shouldn't be directly accessing and modifying its parent form. You would be better off adding an event to #new, raising that event from the button click, then handling that event in your form instance.
For example:
new.cs:
namespace WindowsFormsApp1
{
public partial class #new : UserControl
{
private static #new _instance;
public static #new Instance
{
get
{
if (_instance == null)
_instance = new #new();
return _instance;
}
}
public event EventHandler StepCompleted;
public #new()
{
InitializeComponent();
}
private void choice_button_Click(object sender, EventArgs e)
{
StepCompleted?.Invoke(this, EventArgs.Empty);
}
}
}
And Form1.cs:
namespace WindowsFormsApp1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void new_button_Click(object sender, EventArgs e)
{
if (!container.Controls.Contains(#new.Instance))
{
container.Controls.Add(#new.Instance);
#new.Instance.Dock = DockStyle.Fill;
#new.Instance.BringToFront();
}
else
{
#new.Instance.BringToFront();
}
}
private void new_StepCompleted(object sender, EventArgs e)
{
if (!container.Controls.Contains(choice.Instance))
{
container.Controls.Add(choice.Instance);
choice.Instance.Dock = DockStyle.Fill;
choice.Instance.BringToFront();
}
else
{
choice.Instance.BringToFront();
}
}
}
}
Now you're obviously going to be working on the same form instance, since it itself is the one handling the event. Also, #new doesn't need to do any awkward lookup to find the proper Form1 instance and modify the form.
I am trying to make a method for change usercontrol when a button is clicked.
UserControl
namespace LogAnalyzer
{
public partial class UserSettings : UserControl
{
private static UserSettings _instance;
public static UserSettings Instance
{
get
{
if (_instance == null)
_instance = new UserSettings();
return _instance;
}
}
public UserSettings()
{
InitializeComponent();
}
private void btnUnpackPath_Click(object sender, EventArgs e)
{
flowLayoutPanel1.Hide();
}
}
}
My form
namespace LogAnalyzer
{
public partial class LogAnalyzerMain : Form
{
public LogAnalyzerMain()
{
InitializeComponent();
}
private void ChangeInstance(Control tab) {
if (!panelDisplay.Controls.Contains(tab))
{
panelDisplay.Controls.Add(tab);
tab.Dock = DockStyle.Fill;
}
tab.BringToFront();
}
private void btnSettings_Click(object sender, EventArgs e)
{
ChangeInstance(UserSettings);
}
}
}
It gives me an error in this line in my form ('UserSettings' is a type, which is not valid in the given context)
ChangeInstance(UserSettings);
You are passing the class itself but the method takes an instance of it, since you have a singleton property you could use that:
ChangeInstance(UserSettings.Instance);
Otherwise you had to store the instance somewhere, for example in the LogAnalyzerMain as field or if it's a control on your form you could use this.Controls.OfType<UserSettings>().First()
Every time I create a new instance of Player I want to do the following code
private void button1_Click(object sender, EventArgs e)
{
Player Player1 = new Player();
}
Player class
{
public Player()
{
Form1.AddControls(someControl)
}
}
I can't seem to do anything to do with form1 e.g. textbox1.text = "Test". I assume this is a scope issue but I can't find an answer on the internet. Does anyone know how I can access + add controls to my form1 through a class?
Thank you for your time.
It's not entirely clear what you're trying to do. It sounds like you want to add controls from the Player class into the form that you're calling from like this:
public class Form1 : Form
{
public void SomeMethod()
{
Player player1 = new Player(this);
}
}
public class Player()
{
public Player(Form form)
{
Textbox tb = new Textbox();
form.Controls.Add(tb);
}
}
Currently have a mainForm.cs which calls a class panel.cs
panel.cs holds multiple pictureboxes with events such as _click, _mousedown, _mouseup
I wish to call a function in mainForm.cs from panel.cs
do i need to use a callback / delegate. Is there another way to access this function
I have tried
Main main = new Main();
main.functioninMain does not work
any help or direction would be appreciated.
for example
panel.cs
private void pb_button1_Click(object sender, EventArgs e)
{
this.BeginInvoke(new Action(main.functioninMain));
}
You should not instantiate another object of MainForm, which creates a duplicate and all the objects withing the new MainForm will not have the values of your actual MainForm.
Approach 1
You can try creating a static instance of you MainForm like below
public partial class MainForm : Form
{
public static MainForm Instance = null;
public MainForm()
{
InitializeComponent();
Instance = this;
}
public SomeMethod()
{
}
}
Now if you have your panel class, then you can easily access public methods and variables of MainClass
class Panel : Form
{
public Panel()
{
MainForm.Instance.SomeMethod();
}
}
Edit: Pass Handle as parameter to the form (From Ben Voigt's suggestion)
Approach 2:
As Ben suggested, it is also important to have a safer code, so much cleaner approach will be passing handle of the control as parameter and then to access them.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
TestClass test = new TestClass();
test.ModifyText(textBox1);
}
}
public class TestClass
{
public void ModifyText(TextBox textBox)
{
textBox.Text = "New text";
}
}
If we can use delegate & events something like this
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Panel formPanel = new Panel();
formPanel.OnPanelClick += new Panel.OnPanelButtonClick(formPanel_OnPanelClick);
formPanel.Show();
}
void formPanel_OnPanelClick(string a)
{
MessageBox.Show(a);
}
}
public partial class Panel : Form
{
public delegate void OnPanelButtonClick(string a);
public event OnPanelButtonClick OnPanelClick = null;
public Panel()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
if (OnPanelClick != null)
{
OnPanelClick("from Panel.cs");
}
}
}
You should avoid circular dependencies at all costs (class A depends on class B, and class B depends on Class A).
There are so many ways to do this, but perhaps one of the easier ways is to use an interface. mainForm.cs implements it like this:
public class mainForm : IMainForm {
// This method is defined in the interface, so mainForm
// must implement it.
public string GetStringFromMainForm() {
return "Hello from MainForm";
}
public void CreatePanel() {
// pass in a reference to myself so panel knows how to
// talk to me.
var panel = new Panel(this);
}
}
And IMainForm (the interface) could look like this:
public interface IMainForm {
string GetStringFromMainForm();
}
Then your panel class can talk to the Main form without having to reference mainForm.cs explicitly:
public class Panel {
// use a private variable to keep track of main form
private IMainForm _mainForm;
// Constructor: pass in a class that implements IMainForm. It isn't
// a type of MainForm, so there's no dependency on the concrete class.
public Panel(IMainForm mainForm) {
_mainForm = mainForm;
}
public void TalkToMainForm() {
var resultFromMainForm = _mainForm.GetStringFromMainForm();
Console.WriteLine(resultFromMainForm);
}
}