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The file types that are displayed in Open File Dialog (PNG, BMP, All Files, etc.) are defined by Filter
Then you could use FilterIndex
property to set the wanted file type as default in the open dialog ("All Files"
in your case).
The AddImageInEditor() method from our online documentation demonstrates how you could achieve the needed behavior: link
You can encapsulate this code in a custom command and change the OpenCommand property of RadImageEditorUI to use your command.
I hope this helps. Do not hesitate to get back to us if you have additional questions.
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