We Keep Coding

Auto expand Property when changed PropertyGrid.PropertyValueChanged not works. (ExpandableObjectConverter classes)

I need to expand a PropertyGrid SelectedItem at design-time when I choose a property value. I try create CollectionEditor descendant which access the property grid. and do following in overridden CreateCollectionForm()
protected override CollectionForm CreateCollectionForm()
{
var collectionForm = base.CreateCollectionForm();
collectionForm.Shown += (s, e) =>
{
var propertyGrid = collectionForm.Controls[0].Controls.OfType<PropertyGrid>().First();
propertyGrid.PropertyValueChanged += (ss, ee) =>
{
if (ee.ChangedItem.Expandable)
ee.ChangedItem.Expanded = true; // NOT WORKING.
};
};
return collectionForm;
}
Another guys asking something similar but not answered yet from long time ago. In my case I need expand selectedItem in winForms designer propertygrid.
Automatically expand some properties in PropertyGrid
I see he try cast context as GridItem. Which in my side crash visual studio.
Anyhelp will be appreciated.

To do that a CollectionEditor descendant is must provided as follows:
public class AdvancedCollectionEditor : System.ComponentModel.Design.CollectionEditor
{
protected internal string formCaption;
protected internal List<Type> excludedTypes = new List<Type>();
protected internal bool allowMultiSelect;
public AdvancedCollectionEditor(Type type) : base(type)
{
allowMultiSelect = true;
}
protected override Type[] CreateNewItemTypes()
{
if (CollectionItemType.IsAbstract)
{
List<Type> validTypes = new List<Type>();
var types = Assembly.GetAssembly(CollectionItemType).GetTypes();
foreach (var type in types)
{
if (!type.IsAbstract && type.IsSubclassOf(CollectionItemType))
{
if (!excludedTypes.Contains(type))
validTypes.Add(type);
}
}
return validTypes.ToArray();
}
return base.CreateNewItemTypes();
}
protected override CollectionForm CreateCollectionForm()
{
var collectionForm = base.CreateCollectionForm();
if (!string.IsNullOrWhiteSpace(formCaption))
collectionForm.Text = formCaption;
collectionForm.Size = new Size(640, 500);
collectionForm.Shown += (s, e) =>
{
var propertyGrid = collectionForm.Controls[0].Controls.OfType<PropertyGrid>().First();
propertyGrid.HelpVisible = true;
propertyGrid.PropertyValueChanged += (ss, ee) =>
{
// Note that ee.ChangedItem will never works
void ExpandChildGridItems(GridItem parent)
{
if (parent.Expandable)
parent.Expanded = true;
if (parent.GridItems.Count > 0)
{
foreach (GridItem child in parent.GridItems)
ExpandChildGridItems(child);
}
}
if (propertyGrid.SelectedGridItem.Expandable)
propertyGrid.SelectedGridItem.Expanded = true;
ExpandChildGridItems(propertyGrid.SelectedGridItem);
};
};
return collectionForm;
}
protected override bool CanSelectMultipleInstances() => allowMultiSelect;
}

Android - Turn switch "On" on ListView item click

I have a custom listview in my C# Android app, each row contains a textview, ImageView and a switch. When a Listview item is clicked, I want to turn the row's item switch on.
MainActivity:
List<TableList> list = = new List<TableList>();
list.Add(new TableList("Germany"));
list.Add(new TableList("France"));
list.Add(new TableList("Finland"));
listView.ItemClick += delegate (object sender, AdapterView.ItemClickEventArgs e)
{
string selected = t.Name;
if (selected == "France")
{
// Turn the proper switch for France row ON
}
};
ListAdapter and ListClass for the Listview:
public class ListAdapter : BaseAdapter<TableList>
{
List<TableList> items;
Activity context;
public ListAdapter(Activity context, List<TableList> items)
: base()
{
this.context = context;
this.items = items;
}
public override long GetItemId(int position)
{
return position;
}
public override TableList this[int position]
{
get { return items[position]; }
}
public override int Count
{
get { return items.Count; }
}
public override View GetView(int position, View convertView, ViewGroup parent)
{
var item = items[position];
View view = convertView;
if (view == null) // no view to re-use, create new
view = context.LayoutInflater.Inflate(Resource.Layout.CoinList, null);
view.FindViewById<TextView>(Resource.Id.CoinName).Text = item.Name;
view.FindViewById<ImageView>(Resource.Id.imageView1).SetImageResource(Resource.Drawable.n);
If item is clicked set it on
{
view.FindViewById<Switch>(Resource.Id.switch).SetOn
}
else
{
view.FindViewById<Switch>(Resource.Id.switch).SetOf
}
return view;
}
}
public class TableList
{
public string Name;
public TableList(string Name)
{
this.Name = Name;
}
}
I don't know where I should set the Switch ON (in the listView.ItemClick event or in the ListAdapter) and I don't know how to set it to ON. Please help me to do so.

Here is my demo.
You can choose one to achieve your goal. I will show you how to do this by ItemClick event:
When a Listview item is clicked, I want to turn the row's item switch on.
Because, Switch will grab the focus from ViewGroup. So, I remove the focus from Switch in the MyAdapter:
holder.ms.Focusable = false;//ms is Switch
Now, this is my ItemClick event( turn switch on while click the item):
private void MListView_ItemClick(object sender, AdapterView.ItemClickEventArgs e)
{
var ll = e.View as LinearLayout;
var sw = ll.GetChildAt(1) as Switch;
if (sw.Checked)
{
sw.Checked = false;
adapter.changeState((int)sw.Tag,false);
}
else
{
sw.Checked = true;
adapter.changeState((int)sw.Tag, true);
}
}
As we all know, ListView has reuse problem, so, I add a bool property to control the Switch's state:
public class MyData:Java.Lang.Object {
public MyData(string p,bool b) {
this.position = p;
this.isCheck = b;
}
public string position { get; set; }
public bool isCheck { get; set; }
}
Below is changeState method:
internal void changeState(int position, bool v)
{
mitems[position].isCheck = v;
this.NotifyDataSetChanged();
}
And this is CheckedChange event:
private void Ms_CheckedChange(object sender, CompoundButton.CheckedChangeEventArgs e)
{
var sm = sender as Switch;
Log.Error("Ms_CheckedChange", (int)sm.Tag+"");
if (e.IsChecked&&!mitems[(int)sm.Tag].isCheck)
{
mitems[(int)sm.Tag].isCheck = true;
this.NotifyDataSetChanged();
}
else if(!e.IsChecked&& mitems[(int)sm.Tag].isCheck)
{
mitems[(int)sm.Tag].isCheck = false;
this.NotifyDataSetChanged();
}
}

How to update a ListBox if an element was changed c#

Hi,
I'm struggling a bit using the ListBox.DataSource and the INotifyPropertyChanged Interface. I checked several posts about this issue already but I cannot figure out, how to update the view of a ListBox if an element of the bound BindingList is changed.
I basically want to change the color of an IndexItem after the content has been parsed.
Here the relevant calls in my form:
btn_indexAddItem.Click += new EventHandler(btn_indexAddItem_Click);
lst_index.DataSource = Indexer.Items;
lst_index.DisplayMember = "Url";
lst_index.DrawItem += new DrawItemEventHandler(lst_index_DrawItem);
private void btn_indexAddItem_Click(object sender, EventArgs e)
{
Indexer.AddSingleURL(txt_indexAddItem.Text);
}
private void lst_index_DrawItem(object sender, DrawItemEventArgs e)
{
IndexItem item = lst_index.Items[e.Index] as IndexItem;
if (item != null)
{
e.DrawBackground();
SolidBrush brush = new SolidBrush((item.hasContent) ? SystemColors.WindowText : SystemColors.ControlDark);
e.Graphics.DrawString(item.Url, lst_index.Font, brush, 0, e.Index * lst_index.ItemHeight);
e.DrawFocusRectangle();
}
}
Indexer.cs:
class Indexer
{
public BindingList<IndexItem> Items { get; }
private object SyncItems = new object();
public Indexer()
{
Items = new BindingList<IndexItem>();
}
public void AddSingleURL(string url)
{
IndexItem item = new IndexItem(url);
if (!Items.Contains(item))
{
lock (SyncItems)
{
Items.Add(item);
}
new Thread(new ThreadStart(() =>
{
// time consuming parsing
Thread.Sleep(5000);
string content = item.Url;
lock (SyncItems)
{
Items[Items.IndexOf(item)].Content = content;
}
}
)).Start();
}
}
}
IndexItem.cs
class IndexItem : IEquatable<IndexItem>, INotifyPropertyChanged
{
public int Key { get; }
public string Url { get; }
public bool hasContent { get { return (_content != null); } }
private string _content;
public string Content {
get
{
return (hasContent) ? _content : "empty";
}
set
{
_content = value;
ContentChanged();
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void ContentChanged()
{
if (this.PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs("Content"));
}
}
public IndexItem(string url)
{
this.Key = url.GetHashCode();
this.Url = url;
}
public override bool Equals(object obj)
{
return Equals(obj as IndexItem);
}
public override int GetHashCode()
{
return Key;
}
public bool Equals(IndexItem other)
{
if (other == null) return false;
return (this.Key.Equals(other.Key)) ||
((hasContent || other.hasContent) && (this._content.Equals(other._content)));
}
public override string ToString()
{
return Url;
}
}
Any ideas what went wrong and how to fix it? I'll appreciate any hint...

It seems to me that the control should redraw when it raises the ListChanged event for that item. This will force it to do so:
lst_index.DrawItem += new DrawItemEventHandler(lst_index_DrawItem);
Indexer.Items.ListChanged += Items_ListChanged;
private void Items_ListChanged(object sender, ListChangedEventArgs e)
{
lst_index.Invalidate(); // Force the control to redraw when any elements change
}
So why doesn't it do that already? Well, it seems that the listbox only calls DrawItem if both DisplayMember changed, and if the INotifyPropertyChanged event was raised from the UI thread. So this also works:
lock (SyncItems)
{
// Hacky way to do an Invoke
Application.OpenForms[0].Invoke((Action)(() =>
{
Items[Items.IndexOf(item)].Url += " "; // Force listbox to call DrawItem by changing the DisplayMember
Items[Items.IndexOf(item)].Content = content;
}));
}
Note that calling PropertyChanged on the Url is not sufficient. The value must actually change. This tells me that the listbox is caching those values. :-(
(Tested with VS2015 REL)

Implement jQuery Tag-it functionality in C# Win Form

I would like to implement a functionality similar to jQuery TagIt into C# windows forms.
Here is the link for jQuery - http://aehlke.github.com/tag-it/
I am thinking of creating a user control for this functionality.
Any help on how to go about this?

You're in luck, as there's already a container control called a FlowLayoutPanel that will get you 90% of the way there as a flowing tag host.
FlowLayoutPanel Class # MSDN
This control is available from the Toolbox in Visual Studio, so a good starting point would be to make a custom control based upon a FlowLayoutPanel, and another custom control to represent a tag based upon a Label or Checkbox, and update the drawing and behavior (in the case of a Label) to respond to clicks and to display the [x] to dismiss the tag.
Label Class # MSDN
CheckBox Class # MSDN
After making these two controls, you will need to do additional work to make your FlowLayoutPanel-derived control add/remove Label-based controls representing the state of the tags present.
Update: One thing I missed, a TextBox or other input field would need to be added in place to support adding new tags.
TextBox # MSDN

public class TagLayoutPanel : FlowLayoutPanel
{
//local variables/controls
private TextBox _entryBox;
private Dictionary<string,string> _currentTags;
//events
public delegate void TagsUpdatedHandler(TagEventArgs e);
public event TagsUpdatedHandler TagsUpdated;
//constructor(s)
public TagLayoutPanel()
{
Init();
}
public List<string> GetCurrentTags()
{
var lst = new List<string>();
if (_currentTags != null)
lst = _currentTags.Keys.ToList();
return lst;
}
private void Init()
{
_currentTags = new Dictionary<string, string>();
//Entry box
this.Padding = new Padding(3);
this.BackColor = Color.White;
_entryBox = new TextBox();
_entryBox.BackColor = Color.White;
_entryBox.BorderStyle = System.Windows.Forms.BorderStyle.None;
_entryBox.KeyUp += _entryBox_KeyUp;
this.Controls.Add(_entryBox);
}
private void _entryBox_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
var tag = _entryBox.Text;
if (!string.IsNullOrEmpty(tag))
{
this.AddTag(tag);
_entryBox.Text = String.Empty;
}
}
}
protected override void OnGotFocus(EventArgs e)
{
//Set focus to the textentry box.
base.OnGotFocus(e);
this._entryBox.Focus();
}
public void AddTag(string tag)
{
bool added = false;
if (!_currentTags.ContainsKey(tag))
{
_currentTags.Add(tag, tag);
added = true;
}
if(added)
{
Redraw();
Notify();
}
}
private void Notify()
{
if(TagsUpdated != null)
TagsUpdated(new TagEventArgs(GetCurrentTags().ToArray()));
}
public void Redraw()
{
this.Controls.Clear();
foreach (var tag in _currentTags.Keys)
{
DrawTag(tag);
}
AddEntry();
}
private void AddEntry()
{
this.Controls.Add(_entryBox);
_entryBox.Focus();
}
public void DrawTag(string tag)
{
var lbl = new Label();
lbl.MouseMove += lbl_MouseMove;
lbl.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
lbl.BackColor = Color.LightGray;
lbl.Name = "lbl_" + tag.Replace(" ", "");
lbl.ImageAlign = ContentAlignment.TopRight;
lbl.Text = tag;
lbl.Tag = tag;
lbl.Image = Resources.close_x; //Replace with your own image.
lbl.Click += lbl_Click;
this.Controls.Add(lbl);
}
private void lbl_Click(object sender, EventArgs e)
{
var lbl = (Label)sender;
bool removed = false;
foreach(var item in this.Controls)
{
if(item is Label)
{
if(((Label)item).Tag.ToString() == lbl.Tag.ToString())
{
_currentTags.Remove(lbl.Tag.ToString());
removed = true;
break;
}
}
}
if(removed)
{
Redraw();
Notify();
}
}
private void lbl_MouseMove(object sender, MouseEventArgs e)
{
var lbl = (Label)sender;
var startImgX = lbl.Width - 20;
var endImgY = lbl.Height - 15;
if (e.X >= startImgX && e.Y <= endImgY)
System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Hand;
else
System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Arrow;
}
}
public class TagEventArgs : EventArgs
{
public string[] Tags { get; private set; }
public TagEventArgs(string[] tags)
{
Tags = tags;
}
}

Data binding not updating

I created a simple example with data binding (unfortunately we have a similar case in our system). I created a funky combo box:
public class FunkyComboBox : ComboBox
{
private object currentValue = null;
public FunkyComboBox()
{
if (LicenseManager.UsageMode == LicenseUsageMode.Runtime)
this.Items.Add("Other...");
}
protected override void OnSelectedIndexChanged(EventArgs e)
{
if (!this.Text.StartsWith("Other") && currentValue != this.SelectedItem)
{
currentValue = this.SelectedItem;
BindingManagerBase bindingManager = DataManager;
base.OnSelectedIndexChanged(e);
}
}
protected override void OnSelectionChangeCommitted(EventArgs e)
{
string itemAsStr = this.SelectedItem != null ? SelectedItem.ToString() : "";
if (itemAsStr.StartsWith("Other"))
{
string newItem = "item" + this.Items.Count;
if (!Items.Contains(newItem))
{
Items.Add(newItem);
}
SelectedItem = newItem;
}
else
{
OnSelectedIndexChanged(e); //forces a selectedIndexChanged event to be thrown
base.OnSelectionChangeCommitted(e);
}
}
}
Which adds new items when you click Other (in our system it opens a form where you can query the database, etc). Then I have a simple data object:
public class MyClass
{
private string value;
public string MyData
{
get{ return value;}
set{ this.value = value;}
}
}
And a test form with two controls bound to this object (some designer code removed):
public partial class Form1 : Form
{
MyClass myObj = new MyClass();
public Form1()
{
InitializeComponent();
myObj.MyData = "Nothing";
myClassBindingSource.DataSource = myObj;
}
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.textBox1 = new System.Windows.Forms.TextBox();
this.myClassBindingSource = new System.Windows.Forms.BindingSource(this.components);
this.funkyComboBox1 = new DataBindingTests.FunkyComboBox();
((System.ComponentModel.ISupportInitialize)(this.myClassBindingSource)).BeginInit();
this.SuspendLayout();
//
// textBox1
//
this.textBox1.DataBindings.Add(new System.Windows.Forms.Binding("Text", this.myClassBindingSource, "MyData", true, System.Windows.Forms.DataSourceUpdateMode.OnPropertyChanged));
//
// myClassBindingSource
//
this.myClassBindingSource.DataSource = typeof(DataBindingTests.MyClass);
//
// funkyComboBox1
//
this.funkyComboBox1.DataBindings.Add(new System.Windows.Forms.Binding("SelectedItem", this.myClassBindingSource, "MyData", true, System.Windows.Forms.DataSourceUpdateMode.OnPropertyChanged));
this.funkyComboBox1.DataBindings.Add(new System.Windows.Forms.Binding("SelectedValue", this.myClassBindingSource, "MyData", true, System.Windows.Forms.DataSourceUpdateMode.OnPropertyChanged));
//
// Form1
//
this.Controls.Add(this.textBox1);
this.Controls.Add(this.funkyComboBox1);
((System.ComponentModel.ISupportInitialize)(this.myClassBindingSource)).EndInit();
this.ResumeLayout(false);
this.PerformLayout();
}
private FunkyComboBox funkyComboBox1;
private System.Windows.Forms.BindingSource myClassBindingSource;
private System.Windows.Forms.TextBox textBox1;
}
If you run this code and start playing with the combo box, you will notice that the edit box changes only if you click on it. After every change a null value is set to my object and the text box is cleared. How can I make it set the correct value after every change?

I'm not really sure why the ComboBox data binding behaves this way, but I have found a workaround. It seems as though the databinding doesn't work correctly if you don't use a datasource for your ComboBox's values.
I made a few minor changes to FunkyComboBox, and it now works as expected.
public class FunkyComboBox : ComboBox
{
private object currentValue = null;
private List<string> innerItems = new List<string>();
public FunkyComboBox()
{
if (LicenseManager.UsageMode == LicenseUsageMode.Runtime)
innerItems.Add("Other...");
this.DataSource = innerItems;
}
protected override void OnSelectedIndexChanged(EventArgs e)
{
if (!this.Text.StartsWith("Other") && currentValue != this.SelectedItem)
{
currentValue = this.SelectedItem;
BindingManagerBase bindingManager = DataManager;
base.OnSelectedIndexChanged(e);
}
}
protected override void OnSelectionChangeCommitted(EventArgs e)
{
string itemAsStr = this.SelectedItem != null ? SelectedItem.ToString() : "";
if (itemAsStr.StartsWith("Other"))
{
string newItem = "item" + this.Items.Count;
if(!innerItems.Contains(newItem))
{
innerItems.Add(newItem);
this.RefreshItems();
} SelectedItem = newItem;
}
else
{
OnSelectedIndexChanged(e);
//forces a selectedIndexChanged event to be thrown
base.OnSelectionChangeCommitted(e);
}
}
}

It seems to be a bug with the base ComboBox as well. It is not possible to get this binding source craziness to work correctly.