C#, Root, UI, Windows Phone

A Custom (Async) MessageBox for WPF and Windows Phone

The System.Windows.MessageBox provided by .NET is limited to a very small set of MessageBoxButtons (Yes/No/OK/Cancel) which do not allow for custom Button texts. The System.Windows.Forms.MessageBox also blocks the UI thread, which can be an annoying disadvantage as well. The MessageBox on Windows Phone has the same disadvantages. Custom buttons in a MessageBoxe simplify the decision for the user, because they can describe the results of the action: However you need to do this with a custom control, so for WPF as well as Windows Phone I designed a simple method for asynchronously showing a MessageBox with custom buttons. (The WPF implementation based on this control by Evan Wondrasek) So let’s bring some sample code.In WPF you can use multiple custom buttons: And on Windows Phone you’re limited to 2 buttons: To use CustomMessageBox, you need to get TCD.Controls from NuGet: And on Windows Phone 7.x you also need async support,…

C#, UI, Windows Phone, WinRT

TCD.Device

Just another TCD namespace: TCD.Device. Its purpose is to contain additional namespaces that use features like Camera, GPS, Accelerometer, Compass.. Everything that has an effect on the App permissions the user sees on the Windows Phone or Windows 8 application. (Like ‘This app has access to your location, compass..’) TCD.Device.Camera CodeScannerPopup is another async control, specific to the Windows Phone platform, that can be used to scan for QR codes. (In theory other 2D-codes as well.) Usage: add the TCD.Device.Camera NuGet package add using directives for TCD.Device.Camera and TCD.Device.Camera.Barcodes in the calling method (eg. a Button.Click event) hide/show ApplicationBar, attach/remove BackKeyPress event Code sample: private async void Button_Click(object sender, RoutedEventArgs e) { CodeScannerPopup scp = new CodeScannerPopup(Microsoft.Phone.Shell.SystemTray.IsVisible, Format.ALL_1D); //important: hide ApplicationBar and handle BackKeyPress ApplicationBar.IsVisible = false; this.BackKeyPress += scp.HandleBackKeyPress; //now let’s go ScanResult r = await scp.ShowAsync(“BARCODE SCANNER”, “scan”); if (r != null) output.Text = string.Format(“{0}n{1}”, r.Text, r.Format.ToString()); //clean…

C#, WinRT

Save objects to the ‘LocalFolder’

IMPORTANT: You find the newest versions of TCD.Serialization on NuGet – it works with Windows Phone as well. This post will Show you how to serialize and save objects with XML to your apps LocalFolder/RoamingFolder. Metro style apps in Windows 8 have their own folders where they can store their data. These folders can be accessed by: StorageFolder localFolder = ApplicationData.Current.LocalFolder; StorageFolder roamingFolder = ApplicationData.Current.RoamingFolder; The difference between these two folders is that Windows 8 will synchronise the RoamingFolder between different machines. This can be useful if you want to improve the user experience, for example by synchronising drafts of a blog post between a users tablet and PC. It’s very important, that the data you want to save is serializable. When designing the data structure and classes for your data, you got to make sure, that each class has a parameterless constructor. Properties can be marked with a set…

C#, Software, Windows Phone

Performing long-running, timed operations on the UI thread

Recently I had to play timed sounds (morse code) in a WP7 applications. Sounds are required to be played on the UI thread, but as I had to time them, my UI thread got frozen. The reason was, that I used Thread.Sleep() to time the sound, which of course blocked the UI thread. Today I figured out a way to do this long-running operation (many seconds..) without blocking the UI thread. You may know the Visual Studio Async CTP – it’s required to do the trick. Let’s suppose we already have a method InvokeEvent() that plays the sound, changes a color or something like that. Currently we execute this method in a pattern like this, causing the UI thread to be blocked: void StartOperation()//invoke the event in a pattern { for (int i=0; i<20; i++)//20 times { InvokeEvent();//play the sound, blink with the display or something like that Thread.Sleep(500);//this will…

C#, Software, WinRT

Running a synchronous method in an asynchronous context

In WinRT a significant portion of all native methods are asynchronous. Using an asynchronous method is very easy an can help you to speed up you application. The requirement to use an async method is that the calling method has an async modifier. It’s easy to use async methods from a native API, but it can be useful as well to run synchronous operations off the UI thread. This should be done to prevent the UI thread from beeing blocked by time-consuming or resource-intensive operations like calculating ϖ or the answer to the ultimate question for the life, the universe and everything. To show you how to run things like this asynchronously we take the following synchronous method: private void synchonousMethod() { do { i++; } while (i < Int32.MaxValue / 2); } This method obviously lacks the async and await keywords and it’s usual implementation would be something like…