I am building this view currently:
This is a snapshot of the ios render, the code simply is:
<StackLayout>
<Image Source="img_logo"/>
</StackLayout>
But Android is not quite the same:
I tried everything, giving it verticaloptions, horizontaloptions, changing the aspect to everything, the image is never displayed as it is in ios. It is either clipped, or loses its original aspect ratio. I dont know what else to try here and why I have to do anything in the first place. Please tell me the atributes I need to use...
This code is expected to be rendered differently in some cases.
It is very important what is the target screen density of the image in your platform project. If it is different then obviously it will be rendered at a different size with the code above.
If you want to achieve the same look set the Width or Height property or both. Assuming that the container allows those values (that it is big enough) it will look exactly the same then.
If you want to adjust adjust the size of the image according to the space ratio of different views on the page, you can use Grid to achieve this.
You can set the width to Star or a special value.
For more about this, you can check rows-and-columns.
You can refer to the following code:
<ContentPage.Content>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="200" />
</Grid.RowDefinitions>
<!-- Logo -->
<Image Grid.Row="0"
Source="test.png"
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"
/>
<!-- Sign In Button -->
<StackLayout Grid.Row="1" Padding="10,0,10,0" VerticalOptions="Center">
<Button VerticalOptions="Center" Text="Sign In " />
</StackLayout>
</Grid>
</ContentPage.Content>
Related
In my Xamarin Forms app I have a simple ListView, bound to a collection. Each collection item consists of two strings that I display in Labels. The strings may not fit on one line, in which case they should wrap and take multiple lines.
I cut down the code to the bare minimum to post here:
<ScrollView Orientation="Vertical">
<ListView x:Name="lv" ItemsSource="{Binding MessageItems}" HasUnevenRows="True" Margin="10,10,30,10">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Frame VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" HasShadow="True" BorderColor="#0A2966" Margin="10,10,10,10">
<StackLayout Orientation="Vertical" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand">
<Label x:Name="ShortText" LineBreakMode="NoWrap" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
Short Text
</Label>
<Label x:Name="LongText" LineBreakMode="WordWrap" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" Text="{Binding MessageText}">
This is a long message. It is so long it is going to wrap to the next line. It goes on and on and on to demonstrate word wrapping.
</Label>
</StackLayout>
</Frame>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ScrollView>
This all works as expected in UWP:
But in WPF, it just displays each label on one line, cutting off the text if it does not fit:
I have specified LineBreakMode="WordWrap" in XAML, even though it's the default value, but the text still does not wrap.
There appears to be multiple discussions of labels not wrapping in Xamarin forums, for example this one https://forums.xamarin.com/discussion/79278/word-wrap-on-label-doesnt-appear-to-be-working, but they didn't provide and answer for me.
There is a bug on Github that seems to describe exactly my issue (https://github.com/xamarin/Xamarin.Forms/issues/3558), but it was marked resolved and the fix has been merged a while back. I assume it would already be incorporated in the latest release of Xamarin Forms, but I am not sure how to check.
I am using Xamarin Forms 4.8.0.1534 (the latest version), and I also tried several different 4.8.x and 4.7.x builds without success.
The culprit here is the <Frame> element. I determined this by simplifying your sample code, removing one part or another. Placing <StackLayout> directly inside <ViewCell> (without the intervening <Frame>) fixes the layout and makes Label text wrap as it's supposed to.
Of course, if you do this, you also lose the nice visual border around your labels. Not to worry. We can draw another border and give it the right size and position, so that it looks like it wraps your content. The trick here is to use a Grid and place both the <Frame> and the <StackLayout> into Grid row 0 column 0.
After the above two changes we end up with this:
<ScrollView Orientation="Vertical">
<ListView x:Name="lv" ItemsSource="{Binding MessageItems}" HasUnevenRows="True" Margin="10,10,30,10">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" Margin="10,10,10,10">
<Frame VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" HasShadow="True" BorderColor="#0A2966"/>
<StackLayout Orientation="Vertical" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" Margin="20">
<Label x:Name="ShortText" LineBreakMode="NoWrap" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
Short Text
</Label>
<Label x:Name="LongText" LineBreakMode="WordWrap" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" Text="{Binding MessageText}">
This is a long message. It is so long it is going to wrap to the next line. It goes on and on and on.
</Label>
</StackLayout>
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ScrollView>
Now Labels wrap as expected in both WPF and UWP and the border still shows.
XF WPF is still in BETA ... there are many others issues concerning Labels like spans fontsize ....
Regarding your issue, I guess it is the ListView control. Its development has stopped and Microsoft actively recommends CollectionView or BindableLayout.
I have the need for a scrollview on top of a background image. I found a number of recommendations to use a , making the image the first element. What I end up with is:
<ContentPage>
<ContentPage.Content>
<RelativeLayout Padding="0">
<Image Aspect="AspectFill" Source="Background" />
<ScrollView>
<!-- Various components -->
</ScrollView>
</RelativeLayout>
</ContentPage.Content>
</ContentPage>
Using the above, I get a screen that looks correct, but the ScrollView doesn't scroll.
Am I missing something? Or does anyone have an alternative to the layout above? The background needs to be fixed and not scroll with the other elements on "top" of it.
It turns out there is a way to do this such that the two main requirements (fixed background, scrollable elements) are met.
Instead of using RelativeLayout, use a Grid. The following layout works as needed...
<ContentPage>
<ContentPage.Content>
<!-- Use a Grid, rather than a RelativeLayout -->
<Grid Padding="0">
<Image Aspect="AspectFill" Source="Background" />
<ScrollView>
<!-- Various components -->
</ScrollView>
</Grid>
</ContentPage.Content>
</ContentPage>
I have text block and a button . They are attached in a grid in consecutive colums. There CharacterEllipsis not worked in text block. Code is given below. Please give an idea on how to do this.
The TextTrimming trigger condition is that the length of the current Text exceeds the size of the TextBlock. From that, for TextTrimming to take effect, you can do this in the following two ways:
Set the Width of the TextBlock:
<TextBlock TextTrimming="CharacterEllipsis" Width="100" Text="{x:Bind Name}" .../>
If the width of the TextBlock parent container is fixed and does not need to change with the content size, you can explicitly set TextBlock.Width.
Change container type to Grid:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="1*" />
</Grid.ColumnDefinitions>
<!--First column element-->
<TextBlock TextTrimming="CharacterEllipsis" Grid.Column="1" Text="{x:Bind Name}" .../>
</Grid>
Grid and StackPanel are different. Although its width is also related to content, you can limit the width of a column of the Grid to not exceed the parent container by setting <ColumnDefinition Width="1*" />, which also achieves the purpose of setting the width in disguise.
This method is more flexible and suitable for situations where the width of the container is uncertain.
Best regards.
I have an app that uses the new Shell in Xamarin.Forms. I added the following code to one of my pages in an attempt to use the TitleView area to display my app header image centered. (FYI - I have tried Center for both of the alignment options and it made no difference.)
<Shell.TitleView>
<Image Source="UCIApp.png"
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand" />
</Shell.TitleView>
What I get after doing this is the image in the title bar but centered in the space the excludes the hamburger button on the left as shown below:
What I would prefer is it centered regardless of the space the hamburger menu takes up looking something like this:
Any suggestions?
ALSO - Putting the image in the TitleView is causing it to be shrunk down. Is there any way to avoid that?
Yes, design fail and there is no option customization. I prefer Grid for like this problems. You can use column or row with percentage.
Default place.
<Shell.TitleView>
<Grid>
<ffimageloadingsvg:SvgCachedImage
Source="https://stackoverflow.design/assets/img/logos/so/logo-stackoverflow.svg"
Margin="10"/>
</Grid>
</Shell.TitleView>
In this example 4/5 unit first column and 1/5 unit second column (* sign presents percentage or divide).
<Shell.TitleView>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="4*"/>
<ColumnDefinition Width="1*"/>
</Grid.ColumnDefinitions>
<BoxView BackgroundColor="Yellow"/>
<BoxView Grid.Column="1" BackgroundColor="LightGoldenrodYellow"/>
</Grid>
</Shell.TitleView>
Then add image text or control to prefered layout (image control default column is 0).
<Shell.TitleView>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="4*"/>
<ColumnDefinition Width="1*"/>
</Grid.ColumnDefinitions>
<ffimageloadingsvg:SvgCachedImage
Source="https://stackoverflow.design/assets/img/logos/so/logo-stackoverflow.svg"
Margin="10"/>
</Grid>
</Shell.TitleView>
Edit: Add min height to grid or image control for prevent resize content. Also ffimageloadingsvg is third party package for loading svg files.
I think that's the designed problem about Shell Title View ,you can submit it as a
feature request in GitHub here .
What I would prefer is it centered regardless of the space the hamburger menu takes up looking something like this: ... Any suggestions?
The title view already been placed center in Title View . However , it looks like not center in the whole Navigation Bar . Have a look at follow code and effect .
<Shell.TitleView>
<StackLayout HorizontalOptions="CenterAndExpand"
VerticalOptions="CenterAndExpand"
BackgroundColor="Accent">
<Image Source="xamarin_logo.png"
HorizontalOptions="Center"
VerticalOptions="Center" />
</StackLayout>
</Shell.TitleView>
The effect :
You can see that the content of Title View , And the icon already been center in Title View .Because of existing meun icon , the weight of Title View is not equal with Navigation Bar .
Putting the image in the TitleView is causing it to be shrunk down
Refer to above effect , you can see that The size of the icon is adapted to the Title View display, and you can see the size of the Title View, so your icon is unlikely to exceed the display range of the Title View.
I am trying to resize an ActivityIndicator (in Xamarin.Forms), but the Scale property does not work and the HeightRequest just crops the ActivityIndicator.
<StackLayout>
<ActivityIndicator HorizontalOptions="Center" VerticalOptions="StartAndExpand" HeightRequest="20" IsRunning="True" />
</StackLayout>
This is the result.
Any suggestions on what I might be doing wrong?
It seems sizing itself is not supported on the ActivityIndicator. In this case, scaling is your friend.
The cutting-off you see happening is because the ActivityIndicator is inside a StackLayout. Because of how a StackLayout works, it will only take up the space it needs. Since scaling doesn't necessarily make your ActivityIndicator bigger, you have two options:
Replace your StackLayout with a Grid
Give your ActivityIndicator a WidthRequest and HeightRequest that is big enough to keep your scaled ActivityIndicator
Note: Talking about iOS here. Width and height seem to work on Android
Remove HeightRequest="20", it blocks your scale property.
Code should look like this
<ActivityIndicator HorizontalOptions="Center" VerticalOptions="StartAndExpand" Scale="2" IsRunning="True" />
Now, you can scale to whatever size you want.