How to clear/avoid FFImageLoading's caching in list item image

Question

I am using FFImageLoading instead of Image in my project for more advanced features like placeholders. In my project, there is a list of images needs to show. So I am using a listview for the same.

<ListView x:Name="membersList" ItemTapped="Handle_ItemTappedMember" HorizontalOptions="FillAndExpand" HasUnevenRows="true" SeparatorVisibility="None" BackgroundColor="#EEEEEE" Grid.Row="0" Grid.Column="0">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <ViewCell>
                        <ViewCell.View>
                            <StackLayout Orientation="Horizontal" Padding="5,5,5,5" HeightRequest="75" Margin="10,5,10,5" BackgroundColor="White" HorizontalOptions="FillAndExpand">
                                <ffimageloading:CachedImage Source="{Binding imageUrl}" x:Name="patImage" WidthRequest="60" HeightRequest="60" Aspect="AspectFill" VerticalOptions="Center">
                                    <ffimageloading:CachedImage.Transformations>
                                        <fftransformations:CircleTransformation />
                                    </ffimageloading:CachedImage.Transformations>
                                </ffimageloading:CachedImage>
                                <StackLayout Spacing="3" Orientation="Vertical" VerticalOptions="Center" HorizontalOptions="FillAndExpand">
                                    <Label FontAttributes="Bold" FontSize="14" TextColor="#212121" Text="{Binding FullName}" />
                                    <Label FontSize="12" TextColor="#212121" Text="{Binding Relation}" />
                                    <Label FontSize="12" TextColor="#212121" Text="{Binding Pat_ID}" />
                                </StackLayout>
                            </StackLayout>
                        </ViewCell.View>
                    </ViewCell>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

My problem is that I don't want to use Caching techniques here since my image from server may be changed without change the URL.

I know how to clear a single image view's cache with FFImageLoading

await CachedImage.InvalidateCache(Image.Source, CacheType.All, true);

But how to achieve this in ListView? I am using Binding property to load images here.

Can't you just set the `CacheDuration` property to 0 or -1 or something? — Gerald Versluis, Jun 15 '17 at 08:18
It seems that image is updated when I am relaunch the app again. — Alex Chengalan, Jun 15 '17 at 08:28
can't you just 'foreach' through your images and invalidate the cache? pop it in a background task so you don't block the main UI. — JoeTomks, Jun 15 '17 at 09:02
@Digitalsa1nt Not working with listview :( tried with url that i am passing to it. — Alex Chengalan, Jun 15 '17 at 10:35

score 6 · Accepted Answer · answered Jun 16 '17 at 04:08

After some time spend on the same, I have cleared my problems. In the end it was very simple. In my listview's binding model class, when setting the imageUrl I just cleared cache at the same time with that url.

private string mImageUrl { get; set; }
public string imageUrl
{
get{
     return mImageUrl;
   };
set{
     mImageUrl = value;
     await CachedImage.InvalidateCache(mImageUrl, CacheType.All, true);
   };
}

This will clear the cached image with that imageUrl as key. Thank you everyone for your supports. Happy coding :)

Adil Saiyad · Answer 2 · 2020-02-21T07:15:04.693

1

await not working without async so I added the async method for clean cache.

private string mImageUrl { get; set; }
public string imageUrl
{
get{
     return mImageUrl;
   };
set{
     mImageUrl = value;
     cleanCache();

   };
}

private async void cleanCache()
{
   await CachedImage.InvalidateCache(ImageURL, CacheType.All, true);
}

edited Feb 21 '20 at 07:15

answered Feb 20 '20 at 06:32

Adil Saiyad

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1

You have provided nothing of what you solving you can't just give the end-user a function with not description please make changes explaining ur answer. – c-sharp-and-swiftui-devni Feb 20 '20 at 14:33

How to clear/avoid FFImageLoading's caching in list item image

2 Answers2