I've got a bunch of databound switches on one of my forms:
<Label Grid.Column="0" Grid.Row="0" Text="option 1" VerticalOptions="Center" FontSize="Large" HorizontalOptions="Start"/>
<Switch Grid.Column="1" Grid.Row="0" IsToggled="{Binding Options.One, Mode=TwoWay}" HorizontalOptions="End"/>
<Label Grid.Column="0" Grid.Row="1" Text="option 2" VerticalOptions="Center" FontSize="Large" HorizontalOptions="Start"/>
<Switch Grid.Column="1" Grid.Row="1" IsToggled="{Binding Options.Two, Mode=TwoWay}" HorizontalOptions="End"/>
<Label Grid.Column="0" Grid.Row="2" Text="option 3" VerticalOptions="Center" FontSize="Large" HorizontalOptions="Start"/>
<Switch Grid.Column="1" Grid.Row="2" IsToggled="{Binding Options.Three, Mode=TwoWay}" HorizontalOptions="End"/>
<Label Grid.Column="0" Grid.Row="3" Text="option 4" VerticalOptions="Center" FontSize="Large" HorizontalOptions="Start"/>
<Switch Grid.Column="1" Grid.Row="3" IsToggled="{Binding Options.Four, Mode=TwoWay}" HorizontalOptions="End"/>
<Label Grid.Column="0" Grid.Row="4" Text="option 5" VerticalOptions="Center" FontSize="Large" HorizontalOptions="Start"/>
<Switch Grid.Column="1" Grid.Row="4" IsToggled="{Binding Options.Five, Mode=TwoWay}"/>
Functionally, this is working as expected. However, I'm seeing a bit of an oddity with the UI...
If the binding source provides "true" at the point the page is displayed, the switch control looks as I'd expect - nice and bright, no matter how many times I toggle it.
However, if the binding source provides "false", and you then toggle the switch to "on", then it looks faded - almost as if it's disabled, even though its fully usable.
As I say, the functionality behind this works - my bound properties are getting updated correctly - it's just the visual appearance that's bugging me :)
In this picture, all the bound properties for odd-numbered options was set to "true", whereas the bound properties for the even-numbered ones were set "false".
I've then toggled each option off and on a few times:
This was a bug introduced in XF 4.2.0. To resolve it, you'll need to downgrade to something lower than 4.2.0 or upgrade to Xamarin.Forms 4.4.0.991210-pre2 (4.4.0 Pre Release 2) or higher where the bug was fixed.
If possible, my recommendation would be to upgrade to XF 4.4.0 stable.
Related
I'm trying to achieve dynamic row height in CollectionView control, so that when ever I have more text for a particular property it will extend the height of the frame automatically.
I have tried with ListView as well using HasUnEvenRow property "true" but with that also it's not working.
Here is my code:
<StackLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<Grid RowDefinitions="*,60" BackgroundColor="{StaticResource PageBackgroundColor}" Padding="0" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<CollectionView Grid.Row="0" HorizontalOptions="Fill" VerticalOptions="Fill"
ItemsSource="{Binding Inspections}"
VerticalScrollBarVisibility="Always"
ItemsLayout="VerticalList" ItemSizingStrategy="MeasureAllItems">
<CollectionView.ItemTemplate>
<DataTemplate>
<Frame Padding="15" HasShadow="False">
<Grid HorizontalOptions="Fill"
VerticalOptions="Fill"
BackgroundColor="White"
RowSpacing="25"
RowDefinitions="Auto,Auto,Auto"
ColumnDefinitions="*,Auto">
<StackLayout
Orientation="Horizontal"
Grid.Row="0"
Grid.Column="0">
<Label Text="{Binding Path=BusinessName}"
Style="{StaticResource LabelTitleStyle}" />
<Grid Padding="15,0,0,0">
<baseChip:Chip
HorizontalOptions="Fill" VerticalOptions="Fill"
Style="{StaticResource ChipContainer}"
HasShadow="False"
BackgroundColor="{Binding Path=ChipBackgroundColor}">
</baseChip:Chip>
<Label
Text="{Binding Path=ChipText}"
Style="{StaticResource ChipLabel}"
HorizontalOptions="CenterAndExpand"
VerticalOptions="CenterAndExpand"
TextColor="{Binding Path=ChipTextColor}"/>
</Grid>
</StackLayout>
<Image
Grid.Row="0"
Grid.Column="1"
HorizontalOptions="End"
VerticalOptions="Center"
Aspect="AspectFit">
<Image.Source>
<FontImageSource Glyph="{x:Static helper:MaterialFontHelper.FilePdfBox}"
Color="{StaticResource DarkGray}"
Size="20"
FontFamily="MaterialDesignIcons"/>
</Image.Source>
</Image>
<Grid Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
RowDefinitions="Auto, Auto"
ColumnDefinitions="*, *">
<Label
Grid.Row="0"
Grid.Column="0"
Text="Inspection Type"
Style="{StaticResource LabelKeyStyle}" />
<Label
Grid.Row="1"
Grid.Column="0"
Text="ksd kahdkahd kahd kahd aojsoiud aasjlj sdlkja dlkja da asdadas alsajdlaksjdlajd alsjdalkjd alksjd sa"
Style="{StaticResource LabelValueStyle}" />
<Label
Grid.Row="0"
Grid.Column="1"
Text="Primary Inspector"
Style="{StaticResource LabelKeyStyle}" />
<Label
Grid.Row="1"
Grid.Column="1"
Style="{StaticResource LabelValueStyle}" >
<Label.FormattedText>
<FormattedString>
<Span Text="{Binding Path=InspectorFirstName}"/>
<Span Text=" "/>
<Span Text="{Binding Path=InspectorLastName}"/>
</FormattedString>
</Label.FormattedText>
</Label>
</Grid>
<Grid Grid.Row="2"
Grid.Column="0"
Grid.ColumnSpan="2"
RowDefinitions="*, *"
ColumnDefinitions="*, *">
<Label
Grid.Row="0"
Grid.Column="0"
Text="Scheduled Date"
Style="{StaticResource LabelKeyStyle}" />
<Label
Grid.Row="1"
Grid.Column="0"
Text="{Binding Path=ScheduledStartDate, Converter={StaticResource dateFormatter},ConverterParameter='long'}"
Style="{StaticResource LabelValueStyle}" />
<Label
Grid.Row="0"
Grid.Column="1"
Text="Completed Date"
Style="{StaticResource LabelKeyStyle}" />
<Label
Grid.Row="1"
Grid.Column="1"
Text="{Binding Path=CompletionDate, Converter={StaticResource dateFormatter},ConverterParameter='long'}"
Style="{StaticResource LabelValueStyle}" />
</Grid>
</Grid>
</Frame>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
<StackLayout
Grid.Row="1"
VerticalOptions="End"
HorizontalOptions="FillAndExpand"
BackgroundColor="{StaticResource White}">
<controlTemplate:BeginInspectionContentView></controlTemplate:BeginInspectionContentView>
</StackLayout>
</Grid>
</StackLayout>
Output & expected output image attached here:
How to achieve dynamic height for this UI? Any help or suggestions are welcome.
There are three solutions to this problem:
You can change CollectionView to FlexLayout with BindableLayout.ItemsSource and BindableLayout.ItemTemplate. Then you don't need to set Height for item or FlexLayout because all are dynamic.
You can set a value to collectionView.HeightRequest using MVVM. When item increase, the height will increase as well. For more details about this solution, you may refer to the link.
You can use CollectionView.Behaviors to calculate the Height of every item to increase the height of ContentView. For more details about this solution, you may refer to the link.
You have Grid. With StackLayout. With Grid. With Small Grids inside it.
I will put aside for now, that this is extremely bad for rendering. (It is serious problem however...)
None of the expected output justify this organization.
If you need for element to occupy 2 columns, you can use columns span 2.
Before anything else, please combine all 4 grids in a single grid.
After you are done with that, limit your VisualElements height, or, even better, limit the content you are putting in them. (Because cut content looks bad. You should be using something like "show more" link, that opens popup or whatever).
If you have any questions, please ask.
Edit: Let me clarify:
You have the same Grid code. Most important part - columns are * , * , and rows are auto height. And every 2 rows, you create another GRID, that is copy of the first GRID.
This is extremely counterproductive.
Also, just because you can do something, and it is "working in xamarin", it doesn't mean that you should do it.
First, put everything in the same grid, instead of nesting it and copying grids, then you can start working on CLIP/Height limit/etc.
(Recommending you to test it on IOS, because once you get it running fine there, it is much easier to fine-tune it for other platforms, than the other way around.)
I have a Xamarin Carousel view with the PeakAreaInsets set pretty high so that I can see multiple items in the list at once. However I notice that the current item when set to snap, aligns it self more with the top of the page when I would like it to snap to the center of the page. How can I accomplish this?
Here is a snippet of the code in question:
<ContentPage.Content>
<CarouselView ItemsSource="{Binding Days}"
CurrentItem="{Binding SelectedDay}"
VerticalOptions="Center"
HorizontalOptions="Center"
PeekAreaInsets="300"
x:Name="DayCarousel">
<CarouselView.ItemsLayout>
<LinearItemsLayout SnapPointsAlignment="Center"
SnapPointsType="Mandatory"
Orientation="Vertical"/>
</CarouselView.ItemsLayout>
<CarouselView.ItemTemplate>
<DataTemplate>
<StackLayout Spacing="0"
Orientation="Vertical"
HorizontalOptions="Center"
VerticalOptions="Center"
Margin="30,10">
<Label Text="{Binding FormattedDate}"
HorizontalOptions="Center"
VerticalOptions="Center"
Style="{StaticResource LabelStyle}"/>
<Label Text="{Binding TitleText}"
HorizontalOptions="Center"
VerticalOptions="Center"
Style="{StaticResource LabelHeader1Style}"/>
<StackLayout.GestureRecognizers>
<TapGestureRecognizer Command="{Binding BindingContext.SelectDay, Source={x:Reference this}}"
CommandParameter="{Binding .}"/>
</StackLayout.GestureRecognizers>
</StackLayout>
</DataTemplate>
</CarouselView.ItemTemplate>
</CarouselView>
</ContentPage.Content>
Here is about what it looks like now (just a mock up):
And here is what I would like it to look like:
I ended up playing around with it for a bit. I'm not sure how its going to look on other phone formats and sizes since I haven't tested that yet. But eventually I found a happy medium after tweaking the PeakAreaInsets, and adjusting the SnapPointsAlignment. Currently I have it set to PeakAreaInsets = 350 and SnapPointsAlignment="Start"
I am working on xamarin. form application, where I need to add a image side to the
back button in the navigation bar.
I have tried
1. <NavigationPage.TitleView><image/></NavigationPage.TitleView> -here the view is away from the back button. the space between back button and image is more.
2. created a custom navigation as following.
<Grid BackgroundColor="{Binding ActionbarColor}">
<StackLayout Orientation="Horizontal" Spacing="0" HeightRequest="60" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<Image Source="back.png" HeightRequest="20" WidthRequest="20" HorizontalOptions="Start" VerticalOptions="CenterAndExpand">
<Image.GestureRecognizers>
<TapGestureRecognizer Command="{Binding MoveBackCommand}"></TapGestureRecognizer>
</Image.GestureRecognizers>
</Image>
<Imge Source="defaultUser.png">
<Label />
<Label x:Name="TitleLabel" VerticalTextAlignment="Center" VerticalOptions="CenterAndExpand" TextColor="White" FontAttributes="Bold" FontSize="Medium" HorizontalOptions="FillAndExpand"/>
</StackLayout>
</Grid>
with 2nd, the view is blinking while navigating to the back view.
Apart of these two are there any ways to display the image in the navigation bar side the back button
Use Grid to Change
<Grid VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand" ColumnSpacing="0">
<Grid.RowDefinitions>
<RowDefinition Height="50"/>
</Grid.RowDefinitions>
<BoxView BackgroundColor="Aqua" Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="5"/>
<Button Image="BackIcon" Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="1" Command="GoBack"/>
<Image Source="Logo" Aspect="AspectFit" BackgroundColor="Transparent" Grid.Column="2" Grid.Row="0" Grid.ColumnSpan="1"/>
</Grid>
It not works follow this - if it works let me know
I am not sure whether this is my problem or a problem with Xamarin.
On an iPad my application can load the page which contain a list of data in ListView.
The View Cell inside the ListView can be slightly complex. It contains a profile image, some smaller icons using, which are using FFImageLoading.
On iPad, when I tap a cell of the first page to go into the next page, which contains a list of data, it loads very smoothly.
On Android, when I tap on a cell to go into the next page, the detection of the tap is slow and the loading time of the ListView also very slow.
Is there anyway enhance the performance? I thought it was the data I loaded from SQLite. However, after I comment out the ItemsSource on ListView, the loading time is fine.
This is the datatemplate I've used for displaying the cell.
<ViewCell>
<ViewCell.View>
<StackLayout Spacing="0" Padding="0" VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand">
<StackLayout Orientation="Horizontal" Spacing="10" Padding="0" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<StackLayout Orientation="Horizontal" HorizontalOptions="StartAndExpand">
<controls:CircleImage
Style="{StaticResource profileImageStyle}"
Margin="10, 10, 10, 10"
Source="{Binding Source}"
BorderColor="White"
BorderThickness="2"
VerticalOptions="Center"
HorizontalOptions="Center">
<controls:CircleImage.GestureRecognizers>
<TapGestureRecognizer Tapped="OnChildDetailTapped" />
</controls:CircleImage.GestureRecognizers>
</controls:CircleImage>
<StackLayout VerticalOptions="Fill" Spacing="1" Padding="0,20,0,10" HorizontalOptions="StartAndExpand">
<StackLayout.GestureRecognizers>
<TapGestureRecognizer Tapped="OnChildDetailTapped" />
</StackLayout.GestureRecognizers>
<StackLayout
Orientation="Vertical"
VerticalOptions="Center"
HorizontalOptions="StartAndExpand">
<Label x:Name="childName" Text="{Binding DisplayName}" Style="{StaticResource normalFont}"> </Label>
<local:ChildInfoIconsView
Child="{Binding .}"
VerticalOptions="Fill">
</local:ChildInfoIconsView>
<Label
x:Name="childNotes"
Style="{StaticResource footnoteFont}"
Text="{Binding ChildNotes, StringFormat={x:Static local:AppResources.formatNotes}}"
IsVisible="{Binding HasChildNotes}">
</Label>
<Label
x:Name="noPickupReason"
Style="{StaticResource footnoteFont}"
Text="{Binding NoPickupReason, StringFormat={x:Static local:AppResources.formatNoPickupReason}}"
IsVisible="{Binding HasNoPickupReason}">
</Label>
<Label
x:Name="absentReason"
Style="{StaticResource footnoteFont}"
Text="{Binding AbsentReason, StringFormat={x:Static local:AppResources.formatAbsentReason}}"
IsVisible="{Binding HasAbsentReason}">
</Label>
</StackLayout>
</StackLayout>
</StackLayout>
<StackLayout Orientation="Horizontal" VerticalOptions="FillAndExpand" HorizontalOptions="End">
<StackLayout.Padding>
<OnIdiom x:TypeArguments="Thickness">
<OnIdiom.Phone>5, 20, 10, 20</OnIdiom.Phone>
<OnIdiom.Tablet>10, 30, 30, 30</OnIdiom.Tablet>
</OnIdiom>
</StackLayout.Padding>
<Image
Style="{StaticResource listviewButtonStyle}"
IsVisible="{Binding EnabledSigning, Source={x:Reference page}}"
Source="ic_action_yes.png"
VerticalOptions="FillAndExpand"
HorizontalOptions="End">
<Image.GestureRecognizers>
<TapGestureRecognizer Tapped="OnAttend" />
</Image.GestureRecognizers>
<Image.Margin>
<OnIdiom x:TypeArguments="Thickness">
<OnIdiom.Phone>0, 0, 5, 0</OnIdiom.Phone>
<OnIdiom.Tablet>5, 5, 20, 5</OnIdiom.Tablet>
</OnIdiom>
</Image.Margin>
</Image>
<Image
Style="{StaticResource listviewButtonStyle}"
IsVisible="{Binding EnabledSigning, Source={x:Reference page}}"
Source="ic_action_no.png"
VerticalOptions="FillAndExpand"
HorizontalOptions="End">
<Image.GestureRecognizers>
<TapGestureRecognizer Tapped="OnAbsent" />
</Image.GestureRecognizers>
<Image.Margin>
<OnIdiom x:TypeArguments="Thickness">
<OnIdiom.Phone>5, 0, 0, 0</OnIdiom.Phone>
<OnIdiom.Tablet>20, 5, 5, 5</OnIdiom.Tablet>
</OnIdiom>
</Image.Margin>
</Image>
</StackLayout>
</StackLayout>
</StackLayout>
</ViewCell.View>
</ViewCell>
Try setting a listview caching strategy to improve performance.
See here for more details
Be aware though that you may need to jump through some hoops to use RecycleElement with FFImageLoading. The issue is described here
Also, please post your data template so we can see if it can be simplified.
Use RecyclerView
https://blog.xamarin.com/recyclerview-highly-optimized-collections-for-android-apps/
OR
Use FFImageLoading
https://github.com/luberda-molinet/FFImageLoading
to optimize and for smoother scroll
I'm having a cell view with nested StackLayouts, there's one label that will be wrapped if the text is long, which is the desired behaviour. However, the wrap breaks the LayoutOptions set to (basically) all parent views resulting in a gray gap on the right hand side.
<StackLayout Orientation="Horizontal" BackgroundColor="Gray" Margin="0,30,0,0">
<BoxView
HorizontalOptions="Start"
BackgroundColor="#EEBB00"
WidthRequest="100"
/>
<StackLayout
BackgroundColor="#CC4400"
HorizontalOptions="FillAndExpand"
>
<BoxView
BackgroundColor="Green"
HeightRequest="10"
HorizontalOptions="FillAndExpand"
/>
<Label
FontSize="16"
HorizontalOptions="FillAndExpand"
Text="Name that is toolongandwillbewrapped"
/>
<StackLayout
Orientation="Horizontal"
HorizontalOptions="FillAndExpand"
BackgroundColor="Blue"
>
<Label
FontSize="13"
Text="Left"
TextColor="White"
HorizontalOptions="StartAndExpand"
VerticalTextAlignment="End"
/>
<Label
FontSize="13"
Text="Right"
TextColor="White"
HorizontalOptions="EndAndExpand"
VerticalTextAlignment="End"
/>
</StackLayout>
</StackLayout>
</StackLayout>
The resulting views are:
So I can tell why this is happening, but well, of course I don't like it. The expected behaviour is for the right-hand-side stacklayout to expand all the way to the right. I've tried various ways to circumvent this and would not be here if I had succeeded. Does anybody have an idea?
Unfortunately, it's a bug in Xamarin.Forms (probably, iOS-only).
Bugzilla #28650
Bugzilla #31128
Bugzilla #33841
The workaround in that case is using Grid instead of StackLayout : http://forums.xamarin.com/discussion/comment/152969/#Comment_152969