How to solve this case: multiline text box overlap the controls above it
I had made an input panel using the code below. But I found that when the content of textbox is longger that it's height, the textbox overlaped the button above it, thus user cannot click the button unless the textbox lost focus.

    <StackPanel Name="InputRoot" Background="#FF212021" Height="242" Width="640" Canvas.Left="0" Canvas.Top="-242">
            <StackPanel Orientation="Horizontal">
                <TextBlock Name="PromtText" Margin="15,20,0,0">Type command here.</TextBlock>
                <Button Name="AcceptCommand" Margin="310,0,0,0" Click="AcceptCommand_Click" >Accept</Button>
            </StackPanel>
            <TextBox Name="input" AcceptsReturn="True" TextWrapping="Wrap" Height="166" HorizontalAlignment="Stretch" />
</StackPanel>


  [1]: http://i.stack.imgur.com/u6KVS.jpg
How to solve this case: multiline text box overlap the controls above it
===

I had made an input panel using the code below. But I found that when the content of textbox is longger that it's height, the textbox overlaped the button above it, thus user cannot click the button unless the textbox lost focus.

    <StackPanel Name="InputRoot" Background="#FF212021" Height="242" Width="640" Canvas.Left="0" Canvas.Top="-242">
            <StackPanel Orientation="Horizontal">
                <TextBlock Name="PromtText" Margin="15,20,0,0">Type command here.</TextBlock>
                <Button Name="AcceptCommand" Margin="310,0,0,0" Click="AcceptCommand_Click" >Accept</Button>
            </StackPanel>
            <TextBox Name="input" AcceptsReturn="True" TextWrapping="Wrap" Height="166" HorizontalAlignment="Stretch" />
</StackPanel>


  [1]: http://i.stack.imgur.com/u6KVS.jpg