B4A Library AS Gallery - show images from folders (image- and video-thumbnails)

I want to share my class to create a image preview list like in the gallery app.
This class is based on xCustomListView and PreoptimizedCLV.
The class is creating a cached thumbnail of a image if needed, to avoid performance issues on scrolling.
The cache folder is created here: File.MakeDir(File.DirInternal , "cache")

You can set the tile count, per default it is 4.
I have tested the class with .mp4,.jpg and .png files.

    Dim rp As RuntimePermissions
    rp.CheckAndRequest(rp.PERMISSION_READ_EXTERNAL_STORAGE)
    Wait For Activity_PermissionResult (Permission As String, Result As Boolean)

    Dim tmp_lst As List : tmp_lst.Initialize2(Array As String(File.DirRootExternal & "/Snapchat",File.DirRootExternal & "/Fast InstaSaver"))

    ASGallery1.WildCards = "*.jpg,*.png,*.jpeg,*.bmp"',*.mp4"
    ASGallery1.GetContent(tmp_lst)

ASGallery
Author: Alexander Stolte
Version: 1.03

• ASGallery
  • Events:
    • PreviewClick (path As String, isImage As Boolean)
  • Functions:
    • Class_Globals As String
    • CreateFileAndTime (Name As String, Time As Long, dir As String) As FileAndTime
    • CreateMyImageData (IndexOfFirstImage As Int, lst_image_filename As List) As MyImageData
    • DesignerCreateView (Base As Object, Lbl As Label, Props As Map) As String
      Base type must be Object
    • GetContent (lst_dirs As List)
    • Initialize (Callback As Object, EventName As String) As String
    • IsInitialized As Boolean
      Tests whether the object has been initialized.
    • setWildCards (wildcards As String) As String
    • xclv_main_VisibleRangeChanged (FirstIndex As Int, LastIndex As Int) As String
  • Properties:
    • WildCards
• FileAndTime
  • Fields:
    • dir As String
    • IsInitialized As Boolean
      Tests whether the object has been initialized.
    • Name As String
    • Time As Long
  • Functions:
    • Initialize
      Initializes the fields to their default value.
• MyImageData
  • Fields:
    • IndexOfFirstImage As Int
    • IsInitialized As Boolean
      Tests whether the object has been initialized.
    • lst_image_filename As List
  • Functions:
    • Initialize
      Initializes the fields to their default value.

Changelog

• 1.00
  • Release
• 1.01
  • add get xCustomListView
  • add get mbase
  • add bug fixes
• 1.02
  • add BitmapAsync - only for image files
• 1.03
  • automatically rotates the preview image when it is horizontal
  • new dependency JpegUtils

Have Fun

 

[Alexander Stolte]

If you know how to make the class more performant while he caches the images, tell me. thanks.

 

[scsjc]

Please post a image sample thanks

 

[cambopad]

Cool lib! Will it face Out of memory issue when loading hundreds of photos?

 

[Alexander Stolte]

I've never had any problems and I've displayed my entire gallery with it and that's over 4 thousand pictures. The lib. Makes a thumbnail of the pictures and caches that, so the pictures that are called are very small in size

 

[Alexander Stolte]

Update
The performance for unchached images is much better now

• 1.01
  • add get xCustomListView
  • add get mbase
  • add bug fixes
• 1.02
  • add BitmapAsync - only for image files

[B4X] BitmapsAsync

Don't use this. Better implementation in SimpleMediaManager: https://www.b4x.com/android/forum/threads/b4x-simplemediamanager-smm-framework-for-images-videos-and-more.134716/#content A cross platform library that allows loading images using background threads. It can be useful with keeping the...

www.b4x.com

 

[Alexander Stolte]

Update

• 1.03
  • automatically rotates the preview image when it is horizontal
  • new dependency JpegUtils

 

[bil]

how to change count the tile?

 

[Alexander Stolte]

how to change count the tile?

In the designer.

 

[miladfakhrizade]

how to change asgallery background color?

 

[Alexander Stolte]

how to change asgallery background color?

Try

    ASGallery1.Base.Color = xui.Color_Red
    'or
    ASGallery1.xCustomListView.AsView.Color = xui.Color_Red

But please don't expect further support, this is more an example project to work on yourself.