Problems closing tabs

Question

I've a WPF app organized with tabs. I added a small button to each tabitem header that allow the user to close the tab.

When the user click on the small button, I remove the tabItem from the tabControl.

tabControl.Items.Remove(tabItem);

As result of this the tabItem dissapears, and that is fine, but here comes the problem:

The TabItem is not visible(good), but it still exists(bad). If I put a timer inside, the timer execucutes his Tick, and more important, if I've a datagrid with 200.000 records and I close the Tab, The garbage collector don't release the memory as I expected.

I asked google about the problem and I've implemented some of the advices described. It didn't work.

Can anyone help me? Thanks

Answer 1

Place a user control in your tab, and in the Usercontrol code, handle its own "Unloaded" event.

In there you should be able to clean-up. (unless your timer is preventing the control from unloading, but last time I tried something similar it worked).

And yes, WPF is very dangerous for all those things, if you are not careful you can bleed controls pretty fast...

Answer 2

This is what I've been using, and as far as I can tell it removes the tabitem from memory. The problem with leaving a timer inside of the tabitem, is that the GC won't collect and dispose of it because it detects that the timer is still in use.

The Code:

namespace Reports.Controls
{
    /// <summary>
    /// Interaction logic for Test.xaml
    /// </summary>
    public partial class ReportTab : TabItem
    {
        public delegate void CloseEvents(ReportTab TabIndex);
        public event CloseEvents Closing;

        public ReportTab(string Title)
        {
            InitializeComponent();
            tbTitle.Text = Title;
        }

        private void Image_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            Closing(this);
        }
    }
}

The xaml:

<TabItem x:Class="Reports.Controls.ReportTab"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    >
    <TabItem.Header>
        <StackPanel Orientation="Horizontal">
            <TextBlock Text="Main" Name="tbTitle" Margin="0,0,8,0"/>
            <Image Height="13" 
                   Source="pack://application:,,/Images/Icons/close.png"
                   MouseLeftButtonUp="Image_MouseLeftButtonUp"/>
        </StackPanel>
    </TabItem.Header>
    <Grid>
         //Tabitem stuff
    </Grid>
</TabItem>

Here's the page with the Tabcontrol to add a tab:

void AddTab(string Title)
{
    Controls.ReportTab rt = new Controls.ReportTab(Title);
    rt.Closing += new Controls.ReportTab.CloseEvents(rt_Closing);
    tabControl.SelectedIndex = tabControl.Items.Add(rt);
}

/// <summary>
/// Moves the Tab Control back to the Main tab
/// after a tab is removed
/// </summary>
/// <param name="TabIndex"></param>
void rt_Closing(Controls.ReportTab TabIndex)
{
    tabControl.Items.Remove(TabIndex);
    //This resets the tabcontrol back to it's first tabindex
    tabControl.SelectedIndex = 0;

}