wyDay blog

In todays tip Im going to cover showing drag & drop icons. Specifically keeping the icon overlay shown when you drag files from Windows Explorer to your .NET application. Heres a close-up of a user dragging files from a folder into wyBuild.

If we had used the normal .NET Framework interfaces for dragging files to wyBuild as soon as the cursor passes into the window the icons would disappear.

But, as you can see in the screenshot, the icons stay when dragging over our window. We can also set the drag & drop text to the current folder the user is dragging over.

How to add this to your app

This is one control I cant take credit for. Adam Root from Microsoft wrote up a nice control on his blog in a post Shell Style Drag and Drop in .NET - Part 3. The control works for both Windows Form and Windows Presentation Foundation (WPF) applications.

He wrote a 3 part series, and its interesting if you want to dig into the nitty-gritty Windows API.

How we use Drag & Drop in wyBuild

We use the Windows Form control in wyBuild, but we have to use a little trickery to get it work right. Because Adam wrote the Drag & Drop control using a .NET Framework 3.5 language feature, and wyBuild is built using .NET Framework 2.0, we have to use this little trick from Daniel Moth.

Just add this snippet of code to your project and youll be all set to go.

//HACK: this is to support a .NET language 3.5 feature in .NET 2.0
//see, http://www.danielmoth.com/Blog/2007/05/using-extension-methods-in-fx-20.html
namespace System.Runtime.CompilerServices
{
    public class ExtensionAttribute : Attribute { }
}

7 Days of Windows 7

Join me tomorrow when I talk about Using shield icons, UAC, and process elevation. See the full list of articles in the series.

This will be another easy tip because all the work is already done and wrapped up in a nice little control. Its open source and handles all of the details, get it here.

Progress bars in Windows 7 are nearly identical to what they were in Windows Vista. Theyre green, animated and have 3 states: Normal, Error, and Paused:

Using Windows API

To get both the 3-state progress bar (regular, error, and paused) along with the taskbar progress bar we need to use some Windows API. The easier of the two to implement is changing the state of the progress bar. This works on Windows Vista and Windows 7:

[DllImport("user32.dll", CharSet = CharSet.Auto)]
internal static extern int SendMessage(IntPtr hWnd, int wMsg, int wParam, int lParam);


SetPaused()
{
    // 0x410 = PBM_SETSTATE
    // 0x0003 = PBST_PAUSE
    SendMessage(progressBar.Handle, 0x410, 0x0003, 0);
}


SetError()
{
    // 0x0002 = PBST_ERROR
    SendMessage(progressBar.Handle, 0x410, 0x0002, 0);
}


SetNormal()
{
    // 0x0001 = PBST_NORMAL
    SendMessage(progressBar.Handle, 0x410, 0x0001, 0);
}

Then theres the matter of the taskbar progress bar in Windows 7. You can download the Windows7ProgressBar source code (zip file) to see how I did it, but the gist of it is you need to implement the ITakbarList3 Interface, and then use the SetProgressState to set the state (Normal, Error, Paused, or Marquee) and SetProgressValue to set the value.

7 Days of Windows 7

Join me Monday when I talk about Drag & Drop icons. See the full list of articles in the series.

Those of you who follow this blog regularly already know the tip Im sharing today. Its about the control I created a couple of years ago: VistaMenu.

Normally I would just show a menu from Windows 7 and say this is how you do it. Take the menu above, for example. Its the context menu when you right click the desktop in Windows 7. Its subtle and usable. Its less about being visually appealing than it is about being usable.

I find Windows Vista and Windows 7 menus to be aesthetically pleasing. However, not everyone would agree.

Aesthetics ask 1000 people, get 1000 opinions

How do you judge art? Its damn near impossible to get 100% consensus. Luckily programs arent art they have utility first and style second.

Or, put more simply, if the style detracts from usability it is bad style.

Here are a couple of examples of bad menus. The following menus are tacky for the simple reason that the styling adds no extras usability. The excessive gradients and bad backgrounds distracts from the purpose of the menus:

Difference between MenuStrip and MainMenu

If youve been programming with Windows Forms for any length of time, its very likely you already use MenuStrips and ContextMenuStrips. They are entirely custom-draw menus created by Microsoft and included in .NET Framework 2.0+.

However, the theme of the MenuStrip and ContextMenuStrip controls don't automatically adjust to match the Windows 7 theme. But, as you can see below, the MainMenu and ContextMenu controls do match the Windows 7 theme.

You can add MainMenu & ContextMenu to Visual Studio by right clicking the toolbox, clicking Choose Items and checking the MainMenu and ContextMenu check boxes.

Why you should always use MainMenu

If all the discussion of aesthetics was lost on you, then you should always use MainMenu for two simple reasons:

1. Your program will look like it fits in with all the other programs on your users computers
2. Microsoft does the hard work for you. That is, with each new version of Windows Microsoft subtly tweaks the menu to be more usable.

The MenuStrip and ContextMenuStrip controls are written entirely in C# and will forever look as tacky as they do now. The MainMenu and ContextMenu, however, are simple wrappers around the Windows API. This means that whenever Microsoft updates the menu API in Windows you will get all the usability improvements without lifting a finger.

Look at the screenshot below and you can see how Microsoft even changed the menu API between Windows Vista and Windows 7. The borders are sharper, the colors are tweaked, and the gradient is toned down.

Adding icons to MainMenu and ContextMenus

Microsoft was good enough to add simple API for adding icons to menus. I wrote a .NET wrapper for this API a couple of years ago, VistaMenu. Enough chit-chat, heres how you use VistaMenu. Its open source and works with Windows 98 Windows 7.

7 Days of Windows 7

Join me tomorrow when I talk about Windows 7 progress bars. See the full list of articles in the series.