XLS0501 The property 'Content' is set more than once - xamarin.forms

There is nothing wrong with my code as I can see, but this error I have never seen before keeps coming up, and the Entry element (Input Field) doesn't show up in the UI when I run the app. How to get rid of this problem?
<StackLayout>
<Entry
x:Name="InputField"
Text=""
Placeholder="Enter Todo"
TextChanged="HandleTextChanged"
Completed="HandleCompleted"/>
</StackLayout>
<StackLayout x:Name="TodoList">
</StackLayout>

As Jason suggested in the comments, The Content property of the ContentPage can only accept one direct child element. To get around this, you need to use a Layout container, like a StackLayout or a Grid.
Here's the code sample below for your reference:
<ContentPage.Content>
<StackLayout>
<StackLayout>
<Entry
x:Name="InputField"
Text=""
Placeholder="Enter Todo"
TextChanged="HandleTextChanged"
Completed="HandleCompleted"/>
</StackLayout>
<StackLayout x:Name="TodoList">
</StackLayout>
</StackLayout>
</ContentPage.Content>

Related

Xamarin forms, scrollview doesn't scroll into a StackLayout

i have this:
<StackLayout VerticalOptions="FillAndExpand">
<LineEntry />
<ScrollView VerticalOptions="FillAndExpand">
<StackLayout x:Name="stack" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
</StackLayout>
</ScrollView>
</StackLayout>
But it does not scroll, except if you are into the LineEntry, because the keyboard is up. I think it's because the content page has less height than the scrollView, but don't know how to fix this.
I will update some mockups(can't use the real images) for more information, in the first one, does not works, in the second one, it works:
the content page has less height than the scrollView
This should be the first reason , and the send reason is the Content should exists some things , not a empty layot in ScrollView :
The follow code can work , just for reference :
<StackLayout VerticalOptions="FillAndExpand">
<Entry Text="First Entry"/>
<ScrollView HeightRequest="100" BackgroundColor="Beige" VerticalScrollBarVisibility="Always">
<StackLayout x:Name="stack"
HorizontalOptions="FillAndExpand"
HeightRequest="200">
<Entry Placeholder="Second Entry"/>
</StackLayout>
</ScrollView>
</StackLayout>

Can I create some small views including created views to use it in mainPage?

Can I create a view including Entry Progress bar or others to make a view which I can use in other places?
for example I want to create a card view which I can use to list the lists.
I can only write in the list not to write the card in every list.
Yes, you can create a custom view and use it in the MainPage or other Pages, Views you want.
To create a custom view, add a new item --> ContentView,let's call it CardView:
In .cs of CardView:
public partial class CardView : ContentView
{
public CardView()
{
InitializeComponent();
}
}
In xaml of CardView, add your labels,progressbar, entry there:
<?xml version="1.0" encoding="UTF-8"?>
<ContentView xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:d="http://xamarin.com/schemas/2014/forms/design"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Class="App35.CardView">
<ContentView.Content>
<StackLayout>
<Label Text="Hello Xamarin.Forms!" />
<ProgressBar Progress="0.5" />
<Entry Placeholder="I'm entry"/>
</StackLayout>
</ContentView.Content>
</ContentView>
To use it in MainPage, in listView or in the page:
<StackLayout>
<projectName:CardView HorizontalOptions="Center" VerticalOptions="CenterAndExpand" />
<ListView x:Name="listView" RowHeight="70">
<ListView.ItemsSource>
<x:Array Type="{x:Type x:String}">
<x:String>mono</x:String>
<x:String>monodroid</x:String>
</x:Array>
</ListView.ItemsSource>
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<projectName:CardView HorizontalOptions="Center" VerticalOptions="CenterAndExpand" />
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
I upload a sample here and you can check.
Yes you can do that using ContentView, if you want to use it as views
Or you can make ViewCells if you want to use it in ListViews. Its easy and almost every project does that.
You can refer this link :- https://xamarinhelp.com/xamarin-forms-user-control/
Let me know if you have more questions on this. Thanks!

Xamarin Forms 4.1: ScrollView scroll is covering header view in android device 9.0

In Xamarin Forms 4.1, When scroll, scrollview content is covering/overflow the headerview and scrollview content is not shown completely.
Tried with IsClippedToBounds to true.
Created scrollviewrenderer, OnDraw() -> set clip to bound property. But didn't worked.
Example: Here is the XAML design
<Stacklayout>
<HeaderView/>
<ScrollView IsClippedToBounds="true">
<Stacklayout>
<label text="1"/>
........
........
<label text="100"/>
</Stacklayout>
</ScrollView>
</Stacklayout>
I make a custom control as the headerview in your description. And test on Xamarin.forms 4.1, works well.
MyCustomConrol:
<StackLayout Orientation="Horizontal" BackgroundColor="Aqua">
<Label x:Name="Title_label" Text="Title" TextColor="Black" FontSize="25" HorizontalOptions="StartAndExpand" Margin="8,0,4,0"/>
<Button x:Name="btnHello" Text="Hello" HorizontalOptions="EndAndExpand" Margin="4,0,8,0"/>
</StackLayout>
MainPage.xaml
<StackLayout>
<local:MyCustomControl></local:MyCustomControl>
<!--<HeaderView/>-->
<ScrollView IsClippedToBounds="true">
<StackLayout>
<Label Text="1"/>
<Label Text="2"/>
<Label Text="3"/>
……………
…………………
</StackLayout>
</ScrollView>
Result:
You could download from ScrollView/XamarinDemo folder of GitHub for reference.
https://github.com/WendyZang/Test.git
If you want your header to be always visible then rather than placinf your content in Header, it will be better to place your header content first then below that place your listview. Thus, your header remains intact and listview scrolls.

Picker with custom Items [Xaml]

I am trying to figure out a way how to create a picker with custom items in XAML. I am not sure if it is possible to achieve this task only using xaml. The picker would have to contain items that consist of a label and a switch. The code below illustrates the end goal:
<Picker Title="Picker title here">
<Picker.ItemsSource>
<StackLayout Orientation="Horizontal">
<Label Text="Hello Xamarin.Forms!" />
<Switch />
</StackLayout>
<StackLayout Orientation="Horizontal">
<Label Text="Hello Xamarin.Forms2!" />
<Switch />
</StackLayout>
</Picker.ItemsSource>
</Picker>
It's not possible. I think you can create a Popup with a ListView, where you have a ViewCell with all controls you need

xamarin.Forms DataGrid with editor

I'm trying to embed an editor in a Xamarin.Forms.DataGrid cell using following code (inspired from this sample)
<ContentPage.Content>
<StackLayout>
<dg:DataGrid ItemsSource="{Binding Items}" SelectionEnabled="True" SelectedItem="{Binding SelectedItem}"
RowHeight="70" HeaderHeight="50" PullToRefreshCommand="{Binding RefreshCommand}" IsRefreshing="{Binding IsRefreshing}">
<dg:DataGrid.Columns>
<dg:DataGridColumn Title="Col. 1" PropertyName="Prop. 1" Width="0.7*">
<dg:DataGridColumn.CellTemplate>
<DataTemplate>
<Entry Text="{Binding}" />
</DataTemplate>
</dg:DataGridColumn.CellTemplate>
</dg:DataGridColumn>
</dg:DataGrid.Columns>
</dg:DataGrid>
</StackLayout>
</ContentPage.Content>
Now that works ok, but the edited text is aligned top-left of the cell. So I go trying to use one of the following alignment parameters:
HorizontalOptions="Center" VerticalOptions="Center"
<!-- or >
HorizontalOptions="CenterAndExpand" VerticalOptions="CenterAndExpand"
But in both cases, I end up with text centered within the cell, but now, the editor doesn't expand (it seems as if I had padding)... And the result with either Centeror CenterAndExpand is actually the same:
Could anyone help me get the desired result ?
EDIT: updated with full grid's definition
BONUS question: how to get rid of the editor's border?
You can try this:
<Entry Text="{Binding}" HorizontalTextAlignment="Center" />
Bonus answer: To get rid of border you need custom renderers.

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