In my xamarin forms application, I want to store all colors and fonts information that can be accessed through out the application. One of the most obvious ways is adding them as ResourceDictionary in app.xaml.
App.xaml
<ResourceDictionary>
<Color x:Key="Primary">#78909c</Color>
<Color x:Key="PrimaryDark">#4b636e</Color>
<Style TargetType="NavigationPage">
<Setter Property="BarTextColor" Value="{StaticResource NavigationText}" />
</ResourceDictionary>
I have seen these kind of implementations in sample applications but I was wondering for enterprise level applications are they any efficient or better ways to do it?
If so, can anyone advice a better approach and some example or source with the reason behind it?
MODERATORS
I know this question is more about asking a better approach and has no right and wrong answers but I want to find an efficient way or enterprise level implementation for this. So please don't mark it to close.
It really depends on context and what you need to achieve.
One reason why you may not want to have colors and fonts in your main app.xaml file is readability and maintainability. This is quite subjective however.
A second reason why you may want to split out your colors and fonts is if you need to conditionally apply them or they belong to a Xamarin.Forms theme.
Finally note that if you do require multiple resource dictionaries, you may need to look at the Merged Dictionaries feature, which is available from Xamarin.Forms 2.5 onwards (I previously had to roll my own!). This blog post by the author of the official implementation also has more information.
Related
How can I customize the appearence of xamarin.forms components?
I want each button to have the same image, for instance. Or for all systems to share the same login screen with the same background image.
I know I can do that by adding one specific screen to each platform project. But I want to be able to customize the component itself. Example: All buttons will have the same background image no matter which platform is running.
I've read these:
http://developer.xamarin.com/guides/cross-platform/xamarin-forms/custom-renderer/
http://developer.xamarin.com/guides/cross-platform/xamarin-forms/working-with/styles/
http://code.tutsplus.com/tutorials/getting-started-with-xamarinforms-customizing-user-interface--cms-22144
The most promising one seems to be the last one. Is a custom renderer the only way to accomplish this? Can't I just add an image at the shared project and it automagicaly works for all platforms?
Thanks.
It's not absolutely clear, what exactly you want to reach... but I try to answer you.
If you use a shared project (based on template "Blank App (Xamarin.Forms shared)", you can use the same page / page-definition in all of your platforms.
You can add - e.g. a login-form in the shared-folder and then call it from code (e.g. from another page in the shared folder).
If you want to create your own controls, you can create "user-controls" and use it everywhere you want (what I recommend to every user).
You do this, by create a own class (e.g. with an Entry and a Label), implement the events and then instantiate it where you want to use it. E.G.
var OeFirma = new EntryErfassung(cDefaultText: "Firma", iMaximalLaenge: 45);
where OeFirma is the name of the object-instance on the page (to access it), EntryErfassung is my own class (that contains a description-label, an Entry an error-label and more) and cDefaultText is a parameter, that overtakes and set the default-text to the Entry and iMaximalaenge is a further parameter that is overtaken whereby my class then take care, that not more then 45 Characters are accepted for this Entry).
I have e.g. created a class with a description-label, a delete-button, an Entry and a error-label ad use it on all data-entry-forms.
If you want to change the look-and-feel of a specific control for a specific platform, you can create a "custom-render" (I have done this e.g. to change the font-size to the edit specific for iOS, as the font-sinze cannot be set in the XF-Entry control).
Hope this answers your question...
To do this, you can just specific a style in the App class, (you will need to change the app class to be made up of 2 partials: App.xaml & App.xaml.cs, and then create a ResourceDictionary to hold your customisations.
<Style TargetType="Button">
<Setter Property="Image" Value="MyImage.png"/>
</Style>
Hope that helps.
Cheers,
Tristan
I am reading a design presentation to try and learn some more about android UI. On slide 17, it explains to inherit styles.
https://docs.google.com/file/d/0Bz3qX4EBhUvwZWlHekI3Y0wxSUk/view?sle=true
The developer then says to "Use the framework" and access styles to style your UI. For example, he uses
<style name="MyTheme" parent="android:Theme.Holo.light" />
for sdk versions 11+ in the styles.xml folder. And in the manifest he then sets the theme to "MyTheme". After, he says to reference styles from the current theme, such as
<TextView
style="?android:ListSeparatorTextViewStyle"
...
... />
However, this gives an error that says missing styles. So I researched this and instead found a different way of implementing this as
#android:style/Widget.Holo.Light.TextView.ListSeparator
which gave me an error saying the resource is not public.
So my question is, how can I organize my style.xml, manifest, and layouts to implement android styles like the ones above? What do I need to check to be able to access these styles? Where can I learn about proper organization of these folders and style inheritance? I have tried reading documentation on the android website, but cannot find much help anywhere else. Any advice on where to find other sources on sample code on proper ways to design UI are welcome as well. Thanks for any help.
I'm new to WP7 programming but have XP with other platforms, I am just running through all the basics so I can get to know the language but I have hit a roadblock I've entered a source for my background image:
<Grid x:Name="LayoutRoot">
<Grid.Background>
<ImageBrush ImageSource="C:/users/hypernova/pictures/Background1.jpg">
</ImageBrush>
</Grid.Background>
</Grid>
And the image shows up as a background in the design tab that is next to the XAML but when I debug and the emulator starts its just a black screen no background image, what have I missed? I have tried other ways of setting a background like:
<Grid x:Name="LayoutRoot">
<Canvas>
<Canvas.Background>
<ImageBrush ImageSource="C:/users/hypernova/pictures/Background1.jpg">
</ImageBrush>
</Canvas.Background>
</Canvas>
</Grid>
but the same thing happens I've tried a few other ways also but again nothing, I'm sure I've missed something I should have caught.
The path
C:/users/hypernova/pictures/Background1.jpg
exists on your dev machine, not on any Windows Phone 7+ device.
Remember, users will be downloading your app from the store, then running it on their phones. How would they possibly access your hard drive and get that image?
Unfortunately, since the design surface allows you to do this, it can of course be confusing to a new developer.
What you should do is add your image to your project as a Resource, then reference the resource via a pack URI (don't click on that link unless you want to scare yourself silly).
To add it as a resource, simply add the image to the root of your WP7 project, right click on it, select Properties, and then change the build action to Resource (not Embedded Resource, mind you).
Next, you have to construct a pack URI for this resource. This is ... not easy. You can use the tools in Visual Studio to do this, by editing the properties of your ImageBrush in the designer. This is the simplest, and recommended, route. All you have to do is edit the ImageSource of your ImageBrush in the Properties tool window, and select the image from the list of available images in the solution.
The other way is to manually construct the pack URI. For example, you could take the following
/[project assembly name];component/Background1.jpg
replace [project assembly name] with the name of your assembly (no extensions), and use it as your ImageSource value. You can find the correct project assembly name by looking at the Assembly Name under the Application section of the project properties.
<ImageBrush ImageSource="/MyWp7Application;component/Background1.jpg"/>
Note, depending on how your project folder structure is constructed, this URI may be different. Constructing the correct URI outside of the tools provided is a task deserving of another question.
I have been trying to use some custom fonts within my WP7 app.
I followed the example as per http://www.jeffblankenburg.com/2010/10/24/31-days-of-windows-phone-day-24-embedding-fonts/ but in my project it simply will not pick up the custom font.
I have downloaded the sample project in this example and this one does work okay.
So, I have now used the same font used in there, and included in my project. I have ensured that the properties on the file are identical (Build Action = 'Content' and Copy To Output Directory = "Always")
I have used in my XAML in exactly the same way i.e.
FontFamily="Fonts/DigitalDream.ttf#Digital Dream" FontSize="24"
But to no avail. The custom font is just ignored. Is there something that I am missing, or a setting .. anything that would allow this to work in one project, but not another?
I have discovered that it will work if my XAML page is defined at the root level, i.e. immediately under the project, but in my case I have it in a 'Views' folder.
My understanding was that
FontFamily="/Fonts/DigitalDream.ttf#Digital Dream" FontSize="24"
should start at the root folder of the project?
thanks
Custom fonts can be a little tricky. I spent several hours once trying to embed an .otf font only to find that it just didn't seem to be doable.
You're on the right track, though. A .ttf font should be embedable. It's hard to get the right combination of paths and filenames to make the font work, though.
The easiest way I've found to handle some of these more difficult "magic string" type of situations in XAML is to let Expression Blend do the heavy lifting.
Here's a blog post about using Blend to embed fonts. The nice thing about using Blend is that it gives you some visual indications that things are set up correctly--i.e. you can see the font you want in the font selection menu. This is what finally clued me in on the .otf issue. I couldn't see the font in Blend.
And here's an example of a custom font that I've used in one of my apps:
<TextBlock Name="MyTextblock"
FontFamily="/MyAppName;component/fonts/Fonts.zip#Segoe UI Mono">
That's FontFamily URI is a pain to get right. I'm pretty sure that's your problem.
I was actually having the same problem. I followed everything to the dot and still I wasn't able to embed one particular font. So I created a new project and tried embedding the font there. Still no luck. I then tried embedding some other font. And lo and behold, as soon as I typed the FontFamily attribute, I could see that it had embedded. This was particularly odd since I didn't have to change any properties of the font.
I opened the project in Blend and clicked on the font property box to the right. It took a few seconds and then it embedded the font I was having problems with in the first place.
We are currently migrating our app from VB6 to Net. As the Net forms will be in the minority we want them to blend in as good as possible with the VB6 forms. I thought that forcibly applying the Classic theme would accomplish this. This should be easy but I can't find how to do it. The examples provided target the Aero theme or Net3 which seems to have differently named referenced assemblies.
There are two ways to accomplish this:
Reference the classic.xaml file that is embedded in the Framework:
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/PresentationFramework.Classic;component/themes/classic.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
`
Download the extracted classic.xaml file from here
This file holds a reference to the PresentationUI.dll which does not seem to be part of Net 4 framework. There is just one quixotic Control using this reference, so when you remove the reference and the control you are set to go!
More info here