Xaml 如何更改材质卡片上的不透明度?
在我的HomePage.xaml中,我有材料:MaterialCardXaml 如何更改材质卡片上的不透明度?,xaml,mvvm,xamarin.forms,opacity,Xaml,Mvvm,Xamarin.forms,Opacity,在我的HomePage.xaml中,我有材料:MaterialCard <material:MaterialCard Grid.Column="0" BackgroundColor="{StaticResource CustomizedRedColor}" WidthRequest="70" HeightRequest="70"
<material:MaterialCard Grid.Column="0"
BackgroundColor="{StaticResource CustomizedRedColor}"
WidthRequest="70"
HeightRequest="70"
VerticalOptions="Center"
CornerRadius="4"
Elevation="1"
Padding="5"
x:Name="CreateMQRCard"
Opacity="{Binding Opacity}"
Clicked="MaterialCard_Clicked">
<material:MaterialCard.GestureRecognizers>
<TapGestureRecognizer Command="{Binding CreateMQRCommand}" />
</material:MaterialCard.GestureRecognizers>
<Image Source="create_new_mqr.png"
Aspect="Fill"
HeightRequest="55"
WidthRequest="55"
HorizontalOptions="CenterAndExpand"
VerticalOptions="CenterAndExpand" />
</material:MaterialCard>
然后,在CreateMQR方法中,我试图在导航到另一个页面之前更改不透明度
private async void CreateMQR()
{
Opacity = 0.5;
await Task.Delay(700);
Opacity = 1;
ShowDialog();
await App.Current.MainPage.Navigation.PushAsync(new CreateMQRPage());
HideDialog();
}
导航工作正常,命令调用方法没有问题,不透明度设置为值,但在屏幕上什么也没发生。
不透明度设置为0.5,然后返回到1,我想在单击时创建闪烁效果。与按钮类似,按钮不知道从哪个控件材质卡继承。有一个关于图像的示例,可能对使用有所帮助
XAML:
您可以在单击该函数时使用该函数来实现动画
private async void CreateMQR()
{
Opacity = 0.5;
await Task.Delay(700);
Opacity = 1;
ShowDialog();
await App.Current.MainPage.Navigation.PushAsync(new CreateMQRPage());
HideDialog();
}
<Image x:Name="myimage" Source="icon.png">
<Image.GestureRecognizers>
<TapGestureRecognizer Tapped="TapGestureRecognizer_Tapped"/>
</Image.GestureRecognizers>
</Image>
private void TapGestureRecognizer_Tapped(object sender, EventArgs e)
{
Image image = sender as Image;
image.Opacity = 0;
image.FadeTo(1, 4000);
}