Customized open file dialog
File open dialog is a part of windows subsystem and comes with commdlg32.dll package. In normal senarios we pass the file path buffer and it returns the path which is selected by the user. However there are additional facilities can be given with this dialog. Additional GUI controls can be added using a resource template. A hook procedure can be added to handle the events from these custom controls.
Customization of file open dialog is helpful for applications like Photo editors, audio editors etc. Here are some common usage of custom dialogs.
- An audio application can add a play sound file for preview before opening
- Photo or graphics editor applications can add a thumnail preview of the file
- User can display metadata information like author, revision etc
Here is the demo and we have mainly these steps to make a custom open file dialog.
- Add a dialg bar child resource in the project
- Add necessary button, text, ActiveX or other GUI controls
- Give ID for each controls
- Add OFN_ENABLETEMPLATE and OFN_ENABLEHOOK for OPENFILENAME.Flags
- Add lpTemplateName = MAKEINTRESOURCE(<DIALOGBAR resource ID>)
- Add hook procedure and implement all the notify events needed
- Update the lpfnHook = hook procedure address
Here is the C++ source file followed by the resource script.
///////////////////////////////////////////////////////////////////////////// // // Dialog // IDD_DIALOGBAR DIALOGEX 0, 0, 269, 26 STYLE WS_CHILD FONT 8, "MS Sans Serif" BEGIN LTEXT "Customized File open",IDC_STATIC_HINT,7,7,222,12,0, WS_EX_STATICEDGE PUSHBUTTON "Play",IDC_PLAYPREVIEW,231,7,31,12 END
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