I have a Main window with radio-buttons and a button that open the next window. The next window has big user controls which are made up of many identical smaller user controls. Now when a radio-button is selected it sends its name to the small user controls where it is used as the name of the library for each skin. (The skins are only changing the apperances of small user controls.)
Now the problem I have is that the name of the library reaches the small user control only after its been initialized, which is too late as by then the value of the string name is already considered null and no skin is loaded.
This is the code from the small user control:
public string name ="";
public bool SetSkin(string _Banananas)
{
name = _Banananas;
return true;
}
public SW1()
{
InitializeComponent();
Loaded += OnSkinChanged;
DataContext = this;
IsBlinking = false;
}
private void OnSkinChanged(object sender, RoutedEventArgs e)
{
mg.Resources.Clear();
mg.Resources.MergedDictionaries.Clear();
ResourceDictionary skin = Application.LoadComponent(new Uri("/TestingApp;component/Resources/Skins/" + name + ".xaml", UriKind.Relative)) as ResourceDictionary;
mg.Resources.MergedDictionaries.Add(skin);
e.Handled = true;
}
_Banananas is the string I get from the radio-button.
So any ideas?
I'm not totally sure what the mg object is that you are using in your OnSkinChanged method, but I assume, that you use the App object here.
The problem you are facing is that in WPF the loaded event is raised right after the user interface object is initialized and before you can call any methods on the newly created window or user control.
One "dirty" way to solve this problem is to create another constructor that receives the skin value as a parameter, like so:
public SW1(string skin)
{
InitializeComponent();
SetSkin(skin);
Loaded += OnSkinChanged;
DataContext = this;
IsBlinking = false;
}
Of course, you would have to call this constructor (not the default one) on the code section that creates this user control.
However, there are patterns how to use dynamic themes in WPF and your code doesn't seem to follow them. Just google it or have a look at other questions on Stack Overflow, like this one: https://stackoverflow.com/a/11151024/1560623
Related
I've been working on making a project of mine more modular. Something I've wanted to do is have multiple buttons use the same function when they perform a similar action, but with different values. I've been stuck on trying to apply this to the following situation:
"When this button is clicked, have the user select an image, and then have a PictureBox display the selected image". Each button has its own PictureBox. All Controls have been created before runtime.
Hope that makes sense!
My last attempt can be seen in the code below- I have tried assigning the Controls(Button and PictureBox) to variables to be stored together in a class. There's 6 of these classes all included within a single List.
I've also tried to store only the Control Names and then using this.Controls.Find to retrieve the Controls.
I've tried quite a few smaller changes such as passing by reference, making the List static, and things such as that would (somehow)magically do the trick- I've gotten desperate.
public class score_control
{
public Button score_button;
public PictureBox score_picture;
public int picture_index;
}
public List<string> score_boxes_names = new List<string>();
public List<score_control> score_boxes = new List<score_control>();
public void add_score_control(Button button, PictureBox pictureBox)
{
score_control new_score = new score_control();
new_score.score_button = button;
new_score.score_picture = pictureBox;
new_score.picture_index = score_boxes.Count();
score_boxes.Add(new_score);
score_boxes_names.Add(button.Name);
}
public score_control find_score_control(string name)
{
int index = score_boxes_names.IndexOf(name);
return score_boxes[index];
}
public frm_settings()
{
InitializeComponent();
add_score_control(btn_score1_image1, pic_score1_image1);
add_score_control(btn_score1_image2, pic_score1_image2);
add_score_control(btn_score1_image3, pic_score1_image3);
add_score_control(btn_score2_image1, pic_score2_image1);
add_score_control(btn_score2_image2, pic_score2_image2);
add_score_control(btn_score2_image3, pic_score2_image3);
}
private void score_button_Click(object sender, EventArgs e)
{
Button image_button = (Button)sender;
if (ofd_png.ShowDialog() == DialogResult.OK)
{
score_control clicked_control = find_score_control(image_button.Name);
score_image[clicked_control.picture_index] = ofd_png.FileName;
clicked_control.score_picture.Image = Image.FromFile(ofd_png.FileName);
}
}
The problem seems centered around this line:
clicked_control.score_picture.Image = Image.FromFile(ofd_png.FileName);
The program throws a NullReferenceException , but clickedcontrol is being recognized in the Local Watch, as well as score_image being noted to be a PictureBox(as it should be).
When I instead held the Control Names in the class, I had broke this line down into multiple lines, but the following line produced a NullReferenceException:
Control[] find_control = this.Controls.Find(clicked_control.score_picture, true);
In this case, clicked_control.score_picture would be a string containing the PictureBox Name. Again, the Local Watch showed that it clicked_control was not null, and neither was score_picture.
Any help figuring out how to properly store a Control within a variable to later be used to modify that Control's properties would be greatly appreciated.
dontpanic was able to help me out with this one. The issue was actually outside of this code - it had to do with the line score_image[clicked_control.picture_index] = ofd_png.FileName;. The way score_image was initialized as an array was incorrect. Fixing that made everything work fine.
This is probably a basic question, but I can't find answers because the terms are generic.
I am building a WinForm aplication. Its purpose is to set up memory in a certain chip. I think the best way to organize the application is to have a user control for each chip type, derived from a generic parent class. Think of the children as "iphone," "android" and "blackberry," derived from a parent class "phone".
VS2017 Designer has a Panel where I want the control to be. On startup, I generate an object of the base class and add it to the panel. When I press a button, the old object is deleted and replaced with a new one. Each class has just one control, a label with distinctive text.
The problem is, after I press the button, I see both texts. The panel's Controls collection has just one element, but I see the text from both objects. I have tried Refresh, Update and Invalidate withe the same results.
What do I have to do to make the old text "go away" so the only thing I see is the latest object?
private ChipMemBase ChipMemControl = new ChipMemBase();
public Form1()
{
InitializeComponent();
//tbFeedback.Text = string.Format(fmtString, 0, 1, 2, 3, 4, 5);
cbChipName.SelectedIndex = 0;
tbVersion.Text = Version;
OriginalWindowColor = tbFeedback.BackColor;
ShowChipMemControl();
PrintToFeedback(Version);
}
private void ShowChipMemControl()
{
var ctl = pnlChipMem.GetChildAtPoint(new Point(5,5));
if (null != ctl)
{
if (ctl != ChipMemControl)
{
pnlChipMem.Controls.Remove(ctl);
ctl.Dispose();
pnlChipMem.Update();
Refresh();
}
}
if (null != ChipMemControl)
{
pnlChipMem.Controls.Add(ChipMemControl);
}
}
private void btnMakeChipMemory_Click(object sender, EventArgs e)
{
ChipMemControl = new ChipMemGen2();
ShowChipMemControl();
}
Screenshots before and after clicking Create
Your ShowChipMemControl gets the control at point 5,5 and checks if it's a ChipMemControl then removes it.
I'm guessing that the reason it's not getting removed is that the control at point 5,5 is not a ChipMemControl.
You can use:
pnlChipMem.Controls.Clear()
to remove all the controls
Or:
ChipMemControl cmc = pnlChipMem.Controls.OfType<ChipMemBase>().FirstOrDefault();
if (cmc != null)
{
pnlChipMem.Controls.Remove(cmc);
cmc.Dispose();
}
To only remove the first instance of ChipMemBase on your pnlChipMem panel.
Got it. The problem was from inheritance, not window behavior. Control lblDefault in the base class, carrying the inconvenient text, was still present in the child class. I had to make it Public in the base class and remove it in the child class constructor:
InitializeComponent();
Controls.Remove(lblDefault);
lblDefault.Dispose();
lblDefault = null;
The clue was this article and project:
dynamically-and-remove-a-user-control
in my application i want to implement an options dialog like you have in VisualStudios if you go to Tools->Options in the menubar. How can i do this? My first idea was to use pages and navigation but maybe there's an easier approach?
It's probably not the easiest way but I wrote this snippet that match your goal and it's a good exercise.
In an empty Windows Forms project add a ListBox (listBox1) and a Panel (panel1). Then create 2 UserControls (UserControl1 and UserControl2), these will be the content that is shown when you click the list.
In your Form1 class we create a ListItem class that will contain your menu options as such:
public partial class Form1 : Form
{
public class ListItem
{
public string Text { get; set; }
public UserControl Value { get; set; }
public ListItem(string text, UserControl value)
{
Text = text;
Value = value;
}
};
...
}
After that you add items to the ListBox right after InitializeComponent() in Form1:
public Form1()
{
InitializeComponent();
listBox1.DisplayMember = "Text";
listBox1.ValueMember = "Value";
listBox1.Items.Add(new ListItem("Item1", new UserControl1()));
listBox1.Items.Add(new ListItem("Item2", new UserControl2()));
}
This will make it so when you use listBox1.SelectedItem it will return an object that you can cast to a ListItem and access the associated UserControl.
To make use of this behaviour, go to designmode and double-click the ListBox, this'll add code for the SelectedIndexChanged event. We use this event to display the UserControl in the Panel panel1. This will clear any old Panel content and add a selected UserControl:
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
panel1.Controls.Clear();
UserControl control = (listBox1.SelectedItem as ListItem).Value;
if(control != null)
{
panel1.Controls.Add(control);
control.Dock = DockStyle.Fill;
}
}
I suggest you try adding a button or something to differentiate the UserControls and play around. Have fun! :)
You should create a new Window and show that as opposed to create a page and navigate to it. Then you would call .show() on the new window for it to show.
Then you would change the look of the new window to however you want, the same as editing pages.
If you build your options into a full object model that matches the structure of the options window, then the best way is to use whatever navigation-aware UI binding that your MVVM toolkit uses. The options window would start off as a new root level window to which you would bind the root of your options data model.
So, in short think of the options dialog as a mini-application that uses the same structure as your main MVVM application, but with a different data model root.
If you plan to allow the user to cancel the changes to the options, then you would want your options data model to be clonable so that you can populate the options window with the clone and then swap out the real options with the new data if the user presses OK on the options window. If they select cancel you can just throw the cloned object away and destroy the window.
I create a user control and add a textbox to it. In my windows form I add the user control i created and add a textbox and a button. How to copy the text I input from the textbox of Form to textbox of Usercontrol and vice versa. Something like
usercontrol.textBox1.text = textBox1.text
You could add to your User Control code a public property that delegates into the TextBox's Text property:
public string MyTxtBoxValue { get { return this.txtBox.Text; } }
And you could also have a setter to that, of course, if needed.
What you don't want to do, however, is exposing the whole TextBox by making it public. That is flawed.
From Form to Usercontrol
Form Code
public string ID
{
get { return textBox1.Text; }
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
userControl11.ID = ID;
}
Usercontrol Code
public string ID
{
set { textBox1.Text = value; }
}
There are multiple ways to access your user control text box data. One way to accomplish this would be to expose the text box on the user control at a scope that can be accessed via the form it's loaded on. Another way would be raising an event on the button click of the user control and subscribing to it on the parent form.
Although some stuff are inherited when creating a custom user control, for the most part you have to define your own properties. (like text value, etc..)
I would take a look at this:
http://msdn.microsoft.com/en-us/library/6hws6h2t.aspx
good luck!
I have a windows form application with a ComboBox on it and I have some strings in the box. I need to know how when I select one of the strings and press my create button, how can i make that name show up on another windows form application in the panel I created.
Here is the code for adding a customer
public partial class AddOrderForm : Form
{
private SalesForm parent;
public AddOrderForm(SalesForm s)
{
InitializeComponent();
parent = s;
Customer[] allCusts = parent.data.getAllCustomers();
for (int i = 0; i < allCusts.Length; i++)
{
Text = allCusts[i].getName();
newCustomerDropDown.Items.Add(Text);
newCustomerDropDown.Text = Text;
newCustomerDropDown.SelectedIndex = 0;
}
now when i click the create order button I want the information above to be labeled on my other windows form application.
private void newOrderButton_Click(object sender, EventArgs e)
{
//get the info from the text boxes
int Index = newCustomerDropDown.SelectedIndex;
Customer newCustomer = parent.data.getCustomerAtIndex(Index);
//make a new order that holds that info
Order brandSpankingNewOrder = new Order(newCustomer);
//add the order to the data manager
parent.data.addOrder(brandSpankingNewOrder);
//tell daddy to reload his orders
parent.loadOrders();
//close myself
this.Dispose();
}
The context is not very clear to me, but if I got it right, you open an instance of AddOrderForm from an instance of SalesForm, and when you click newOrderButton you want to update something on SalesForm with data from AddOrderForm.
If this is the case, there are many ways to obtain it, but maybe the one that requires the fewer changes to your code is this one (even if I don't like it too much).
Make the controls you need to modify in SalesForm public or at least internal (look at the Modifiers property in the Design section of the properties for the controls). This will allow you to write something like this (supposing customerTxt is a TextBox in SalesForm):
parent.customerTxt.Text = newCustomerDropDown.SelectedItem.Text;