My suggestion is that you replace each of the Textbox's with a DockPanel . Each of them has Image as the leftmost element, and Textbox as the rightmost. Then set the images to "User" and "Block" respectively. Then set the Textbox and Images background to transparent. Then you can set whatever style you want on the DockPanel .
EDIT 1 - Copy paste from a working example
Code:
<DockPanel> <Button BorderThickness="0" DockPanel.Dock="Left" HorizontalAlignment="Right" Height="28" Width="23"> <DynamicResource ResourceKey="SearchBar"/> </Button> 'This is a button, because I have a custom Style which I am using which makes all the borders go away. And also because I use it to clear the field. <TextBox Text="Search..." FontSize="16" HorizontalAlignment="Stretch" Background="Transparent"/> </DockPanel>
Picture

Without setting the DockPanel.Dock property in the second element, I tell it to stretch along the rest of the DockPanel . Any other questions, please let me know. If you copy the insert above, it may not look like that, because of me, cutting out unnecessary parts.
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