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New Comment on "Documentation"

orkazaz — Fri, 15 Jun 2012 14:17:00 GMT

You can make life more easy for adding custom controls. It's not enough to: "Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs"." Because in the AllSupportedTombstoners method the first thing is a foreach loop that checks if the control type exists in the property: "SupportedTypes". Because we didn't add the new custom type to that list we will get an exception. Even if we did add the 2 enteries like written above: // There will be errors if the unsupported types have been passed in the filter. // Highlight this by raising an error foreach (var type in filteredTypesToSave) { if (!SupportedTypes.Contains(type) && !TombstoneHelperExtensibility.CustomTombstoners.ContainsKey(type)) { throw new ArgumentException(string.Format("TombstoneHelper doesn't know how to handle the type: {0}{1}You could create and register a custom tombstoner for this type or remove it from the list of types to use.", type.ToString(), System.Environment.NewLine)); } } You can fix it in 2 ways: (1) Add the 2 enteries like you said AND add the new type to the SupportedTypes list property hardcoded. OR (2) At the begining of the method "AllSupportedTombstoners" (Before the type checker foreach) call a new static method, AND also add the call for this method to begining of the "AllTombstoneRestorers" method. /// <summary> /// TODO: Register here all the custom tombstoners /// </summary> private static void RegisterAllCustomTombstoners() { TombstoneHelperExtensibility.RegisterCustomTombstoner(typeof(TextBlock), new TextBlockTombstoner()); } this method uses the RegisterCustomTombstoner method inside the class "TombstoneHelperExtensibility". I prefer the second option because you don't have to add the above written 2 enteries hardcoded for every new custome support for a new control. Just add a single line to this new method :-) And besides, this way the CustomTombstoners actually means something.

New Comment on "Documentation"

orkazaz — Fri, 15 Jun 2012 11:47:44 GMT

You can make life more easy for adding custom controls. It's not enough to: "Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs"." Because in the AllSupportedTombstoners method the first thing is a foreach loop that checks if the control type exists in the property: "SupportedTypes". Because we didn't add the new custom type to that list we will get an exception. Even if we did add the 2 enteries like written above: // There will be errors if the unsupported types have been passed in the filter. // Highlight this by raising an error foreach (var type in filteredTypesToSave) { if (!SupportedTypes.Contains(type) && !TombstoneHelperExtensibility.CustomTombstoners.ContainsKey(type)) { throw new ArgumentException(string.Format("TombstoneHelper doesn't know how to handle the type: {0}{1}You could create and register a custom tombstoner for this type or remove it from the list of types to use.", type.ToString(), System.Environment.NewLine)); } } You can fix it in 2 ways: (1) Add the 2 enteries like you said AND add the new type to the SupportedTypes list property hardcoded. OR (2) At the begining of the method "AllSupportedTombstoners" (Before the type checker foreach) call a new static method: /// <summary> /// TODO: Register here all the custom tombstoners /// </summary> private static void RegisterAllCustomTombstoners() { TombstoneHelperExtensibility.RegisterCustomTombstoner(typeof(TextBlock), new TextBlockTombstoner()); } this method uses the RegisterCustomTombstoner method inside the class "TombstoneHelperExtensibility". I prefer the second option because you don't have to add the above written 2 enteries hardcoded. Just add a single line to this new method. And besides, this way the CustomTombstoners actually means something.

Updated Wiki: Home

mrlacey — Tue, 13 Mar 2012 15:05:17 GMT

Tombstoning support just got REALLY simple!

This library adds extension methods to PhoneApplicationPage so you don't have to worry about maintaining the state of a page in your app if it gets tombstoned.

It just takes 2 lines of code!

protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
    this.SaveState(e);  // <- first line
}

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    this.RestoreState();  // <- second line
}

If you add the above to your code then the contents, checked state and scroll positions of TextBoxes, PasswordBoxes, CheckBoxes, RadioButtons, Sliders, ListBoxes and ScrollViewers will be preserved.

If you want to add support for other types this can be done as the code was designed to be easily extensible.

The code is optimised for performance but if you don't use all of those types on your page you can get even better performance by just specifying the types of the objects you wish to save the state of:

    this.SaveState(typeof(ScrollViewer));
or 
    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));
or 
    this.SaveState<TextBox, PasswordBox, CheckBox>();

Yes. It's reallly that simple.

You just need to make sure you're given a name to the object you wish to save the state of.

    <TextBox Name="thisHasANameAndSoWillBeSaved" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->

Please note that there are much better ways of using it. See the Documentation page for more details.

All feedback, comments, questions, etc. greatly appreciated.

Updated Wiki: Home

mrlacey — Fri, 13 Jan 2012 11:28:58 GMT

Tombstoning support just got REALLY simple!

This library adds extension methods to PhoneApplicationPage so you don't have to worry about maintaining the state of a page in your app if it gets tombstoned.

It just takes 2 lines of code!

protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
    this.SaveState(e);  // <- first line
}

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    this.RestoreState();  // <- second line
}

    this.SaveState(typeof(ScrollViewer));
or 
    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

Yes. It's reallly that simple.

You just need to make sure you're given a name to the object you wish to save the state of.

    <TextBox Name="thisHasANameAndSoWillBeSaved" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->

Please note that there are much better ways of using it. See the Documentation page for more details.

All feedback, comments, questions, etc. greatly appreciated.

New Comment on "Documentation"

mrlacey — Fri, 30 Sep 2011 17:36:01 GMT

@Pluginbaby - good spot. The base calls are acutally unnecessary as they don't actually do anything. Just a result of my Resharper generated code. The wrong method being called was a result of me not updating everything correctly. :(

Updated Wiki: Documentation

mrlacey — Fri, 30 Sep 2011 17:34:21 GMT

Installation
Usage
Adding support for other types
Gotchas

Installation

Download the library
Add a reference to it in your project

Or use NuGet: http://www.nuget.org/List/Packages/WP7TombstoneHelper

Usage

Simple usage

Include a reference to the namespace:

using TombstoneHelper;

In any pages that have something you may want to preserve during tombstoning, simply call SaveState(e) in the OnNavigatingFrom handler and RestoreState() in the OnNavigatedTo handler.
Note that I'm using OnNavingatingFrom method, rather than OnNavigatedFrom, as it allows us to detect the direction of navigation. This means we don't save state if we know we won't need it again. This can help improve the performance of the app.

    protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e)
    {
        this.SaveState(e); 
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        this.RestoreState();
    }

Ensure that every object you want to be preserved has a Name specified.
The code below is from "TextBoxes.xaml" in the demo project included with the source. It shows three textboxes, the middle of which won't have it's text automatically preserved during tombstoning.

    <TextBlock Text="first (has name)" />
    <TextBox Name="first" />
    <TextBlock Text="second (doesn't have name)" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->
    <TextBlock Text="third (has name)" />
    <TextBox Name="third" />

That's it!

Slightly more advanced usage

If you want to improve performance you can specify only the types of the controls which you want to be preserved when calling SaveState().
eg:

    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

    this.SaveState(typeof(ScrollViewer));

or in a more generic style

    this.SaveState<ScrollViewer>();

    this.SaveState<ListBox, TextBox>();

Not only does this improve performance but it makes it easy to integrate this functionality to save some properties (typically the scroll position of a ListBox or ScrolViewer) where there is already a view model which preserves the data state.

Adding support for other types

Add a new class to the project which implements ICanTombstone.
Add the necessary code to implement the functionality. N.B. The key used for saving the state of the object should be a string comprising the name of the type and the name of the object separated by a '^' character.
Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs".

If you are adding support for additional types then reviewing the exising implementations of ICanTombstone is highly recommended.

Gotchas

You may experience strange behaviour or unwanted side effects in the following situations

If you have an event that is triggered upon setting the property that automatically preserved. e.g. If it's a TextBox and you're handling the TextChanged event—it may have too account for it being triggered additional times.
If you are databinding the property which is has events or actions in response to setting it.
If you are generating the UI in code at runtime.
If you are also doing something with the State object yourself then do it after calling SaveState() as it will clear the contents of the state object to ensure it doen't have anything more than it needs in it.

If one of these scenarios does cause a problem then get in touch as there may be a workaround.

New Comment on "Documentation"

Pluginbaby — Fri, 30 Sep 2011 02:47:30 GMT

Awesome project! There is a mistake in the sample of this page: Replace: protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e) { this.SaveState(e); base.OnNavigatedFrom(); } With: protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e) { this.SaveState(e); base.OnNavigatingFrom(); }

Updated Wiki: Home

mrlacey — Mon, 19 Sep 2011 20:03:56 GMT

Tombstoning support just got REALLY simple!

This library adds extension methods to PhoneApplicationPage so you don't have to worry about maintaining the state of a page in your app if it gets tombstoned.

It just takes 2 lines of code!

    protected override void OnNavigatingFrom(System.Windows.Navigation.NavigationEventArgs e)
    {
        this.SaveState(e);  // <- first line
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        this.RestoreState();  // <- second line
    }

    this.SaveState(typeof(ScrollViewer));
or 
    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

Yes. It's reallly that simple.

You just need to make sure you're given a name to the object you wish to save the state of.

    <TextBox Name="thisHasANameAndSoWillBeSaved" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->

Please note that there are much better ways of using it. See the Documentation page for more details.

All feedback, comments, questions, etc. greatly appreciated.

Updated Wiki: Documentation

mrlacey — Fri, 29 Jul 2011 21:05:49 GMT

Installation
Usage
Adding support for other types
Gotchas

Installation

Download the library
Add a reference to it in your project

Or use NuGet: http://www.nuget.org/List/Packages/WP7TombstoneHelper

Usage

Simple usage

Include a reference to the namespace:

using TombstoneHelper;

    protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e)
    {
        this.SaveState(e); 

        base.OnNavigatedFrom();
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        this.RestoreState();

        base.OnNavigatedTo(e);
    }

    <TextBlock Text="first (has name)" />
    <TextBox Name="first" />
    <TextBlock Text="second (doesn't have name)" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->
    <TextBlock Text="third (has name)" />
    <TextBox Name="third" />

That's it!

Slightly more advanced usage

If you want to improve performance you can specify only the types of the controls which you want to be preserved when calling SaveState().
eg:

    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

    this.SaveState(typeof(ScrollViewer));

or in a more generic style

    this.SaveState<ScrollViewer>();

    this.SaveState<ListBox, TextBox>();

Adding support for other types

Add a new class to the project which implements ICanTombstone.
Add the necessary code to implement the functionality. N.B. The key used for saving the state of the object should be a string comprising the name of the type and the name of the object separated by a '^' character.
Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs".

If you are adding support for additional types then reviewing the exising implementations of ICanTombstone is highly recommended.

Gotchas

You may experience strange behaviour or unwanted side effects in the following situations

If you have an event that is triggered upon setting the property that automatically preserved. e.g. If it's a TextBox and you're handling the TextChanged event—it may have too account for it being triggered additional times.
If you are databinding the property which is has events or actions in response to setting it.
If you are generating the UI in code at runtime.
If you are also doing something with the State object yourself then do it after calling SaveState() as it will clear the contents of the state object to ensure it doen't have anything more than it needs in it.

If one of these scenarios does cause a problem then get in touch as there may be a workaround.

Updated Wiki: Documentation

mrlacey — Fri, 29 Jul 2011 20:37:03 GMT

Installation
Usage
Adding support for other types
Gotchas

Installation

Download the library
Add a reference to it in your project

Or use NuGet: http://www.nuget.org/List/Packages/WP7TombstoneHelper

Usage

Simple usage

Include a reference to the namespace:

using TombstoneHelper;

    protected override void OnNavigatingFrom(System.Windows.Navigation.NavigatingCancelEventArgs e)
    {
        this.SaveState(e); 

        base.OnNavigatedFrom();
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        this.RestoreState();

        base.OnNavigatedTo(e);
    }

    <TextBlock Text="first (has name)" />
    <TextBox Name="first" />
    <TextBlock Text="second (doesn't have name)" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->
    <TextBlock Text="third (has name)" />
    <TextBox Name="third" />

That's it!

Slightly more advanced usage

If you want to improve performance you can specify only the types of the controls which you want to be preserved when calling SaveState().
eg:

    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

    this.SaveState(typeof(ScrollViewer));

Adding support for other types

Add a new class to the project which implements ICanTombstone.
Add the necessary code to implement the functionality. N.B. The key used for saving the state of the object should be a string comprising the name of the type and the name of the object separated by a '^' character.
Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs".

If you are adding support for additional types then reviewing the exising implementations of ICanTombstone is highly recommended.

Gotchas

You may experience strange behaviour or unwanted side effects in the following situations

If you have an event that is triggered upon setting the property that automatically preserved. e.g. If it's a TextBox and you're handling the TextChanged event—it may have too account for it being triggered additional times.
If you are databinding the property which is has events or actions in response to setting it.
If you are generating the UI in code at runtime.
If you are also doing something with the State object yourself then do it after calling SaveState() as it will clear the contents of the state object to ensure it doen't have anything more than it needs in it.

If one of these scenarios does cause a problem then get in touch as there may be a workaround.

Updated Wiki: Home

mrlacey — Fri, 29 Jul 2011 20:29:44 GMT

Tombstoning support just got REALLY simple!

This library adds extension methods to PhoneApplicationPage so you don't have to worry about maintaining the state of a page in your app if it gets tombstoned.

It just takes 2 lines of code!

    protected override void OnNavigatedFrom(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedFrom(e);

        this.SaveState();  // <- first line
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedTo(e);

        this.RestoreState();  // <- second line
    }

    this.SaveState(typeof(ScrollViewer));
or 
    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

Yes. It's reallly that simple.

You just need to make sure you're given a name to the object you wish to save the state of.

    <TextBox Name="thisHasANameAndSoWillBeSaved" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->

Please note that there are much better ways of using it. See the Documentation page for more details.

All feedback, comments, questions, etc. greatly appreciated.

Updated Wiki: Roadmap

mrlacey — Mon, 16 May 2011 20:27:39 GMT

The following are ideas for adding to future versions of this library. No promises that any of these will make it in but just a record of what I'm thinking about.
If you've got a particular desire to see any of these with increased priority or if there's anythign you think should be added then please let me know.

better handling for custom handlers (having to specify them on restore as well as save is far from ideal)
support for maps control?
support for mediaelement
add support for callbacks on restore which are set at save
example handlers for all controls in the toolkit

Updated Wiki: Documentation

mrlacey — Thu, 14 Apr 2011 11:30:14 GMT

Installation
Usage
Adding support for other types
Gotchas

Installation

Download the library
Add a reference to it in your project

Or use NuGet: http://www.nuget.org/List/Packages/WP7TombstoneHelper

Usage

Simple usage

Include a reference to the namespace:

using TombstoneHelper;

In any pages that have something you may want to preserve during tombstoning, simply call SaveState() in the OnNavigatedFrom handler and RestoreState() in the OnNavigatedTo handler.

    protected override void OnNavigatedFrom(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedFrom(e);

        this.SaveState(); 
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedTo(e);

        this.RestoreState();
    }

    <TextBlock Text="first (has name)" />
    <TextBox Name="first" />
    <TextBlock Text="second (doesn't have name)" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->
    <TextBlock Text="third (has name)" />
    <TextBox Name="third" />

That's it!

Slightly more advanced usage

If you want to improve performance you can specify only the types of the controls which you want to be preserved when calling SaveState().
eg:

    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

    this.SaveState(typeof(ScrollViewer));

Adding support for other types

Add a new class to the project which implements ICanTombstone.
Add the necessary code to implement the functionality. N.B. The key used for saving the state of the object should be a string comprising the name of the type and the name of the object separated by a '^' character.
Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs".

If you are adding support for additional types then reviewing the exising implementations of ICanTombstone is highly recommended.

Gotchas

You may experience strange behaviour or unwanted side effects in the following situations

If you have an event that is triggered upon setting the property that automatically preserved. e.g. If it's a TextBox and you're handling the TextChanged event—it may have too account for it being triggered additional times.
If you are databinding the property which is has events or actions in response to setting it.
If you are generating the UI in code at runtime.
If you are also doing something with the State object yourself then do it after calling SaveState() as it will clear the contents of the state object to ensure it doen't have anything more than it needs in it.

If one of these scenarios does cause a problem then get in touch as there may be a workaround.

Updated Wiki: Documentation

mrlacey — Sat, 26 Mar 2011 11:11:31 GMT

Installation
Usage
Adding support for other types
Gotchas

Installation

Download the library
Add a reference to it in your project

Or use NuGet: http://www.nuget.org/List/Packages/WP7TombstoneHelper

Usage

Simple usage

Include a reference to the namespace:

using TombstoneHelper;

In any pages that have something you may want to preserve during tombstoning, simply call SaveState() in the OnNavigatedFrom handler and RestoreState() in the OnNavigatedTo handler.

    protected override void OnNavigatedFrom(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedFrom(e);

        this.SaveState(); 
    }

    protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
    {
        base.OnNavigatedTo(e);

        this.RestoreState();
    }

    <TextBlock Text="first (has name)" />
    <TextBox Name="first" />
    <TextBlock Text="second (doesn't have name)" />
    <TextBox /><!--This TextBox does not have a name so it's contents won't be automatically saved and restored -->
    <TextBlock Text="third (has name)" />
    <TextBox Name="third" />

That's it!

Slightly more advanced usage

If you want to improve performance you can specify only the types of the controls which you want to be preserved when calling SaveState().
eg:

    this.SaveState(typeof(TextBox), typeof(PasswordBox), typeof(CheckBox));

    this.SaveState(typeof(ScrollViewer));

Adding support for other types

Add a new class to the project which implements ICanTombstone.
Add the necessary code to implement the functionality. N.B. The key used for saving the state of the object should be a string comprising the name of the type and the name of the object separated by a '^' character.
Add appropriate entries to AllTombstoneRestorers() and AllSupportedTombstoners() in "PhoneApplicationPageExtensions.cs".

If you are adding support for additional types then reviewing the exising implementations of ICanTombstone is highly recommended.

Gotchas

You may experience strange behaviour or unwanted side effects in the following situations

If you have an event that is triggered upon setting the property that automatically preserved. e.g. If it's a TextBox and you're handling the TextChanged event—it may have too account for it being triggered additional times.
If you are databinding the property which is has events or actions in response to setting it.
If you are generating the UI in code at runtime.

If one of these scenarios does cause a problem then get in touch as there may be a workaround.

tombstonehelper Wiki Rss Feed

New Comment on "Documentation"

New Comment on "Documentation"

Updated Wiki: Home

Tombstoning support just got REALLY simple!

Yes. It's reallly that simple.

Updated Wiki: Home

Tombstoning support just got REALLY simple!

Yes. It's reallly that simple.

New Comment on "Documentation"

Updated Wiki: Documentation

Contents

Installation

Usage

Simple usage

Slightly more advanced usage

Adding support for other types

Gotchas

New Comment on "Documentation"

Updated Wiki: Home

Tombstoning support just got REALLY simple!

Yes. It's reallly that simple.

Updated Wiki: Documentation

Contents

Installation

Usage

Simple usage

Slightly more advanced usage

Adding support for other types

Gotchas

Updated Wiki: Documentation

Contents

Installation

Usage

Simple usage

Slightly more advanced usage

Adding support for other types

Gotchas

Updated Wiki: Home

Tombstoning support just got REALLY simple!

Yes. It's reallly that simple.

Updated Wiki: Roadmap

Updated Wiki: Documentation

Contents

Installation

Usage

Simple usage

Slightly more advanced usage

Adding support for other types

Gotchas

Updated Wiki: Documentation

Contents

Installation

Usage

Simple usage

Slightly more advanced usage

Adding support for other types

Gotchas