B4J Question Why are this imageview's borders flickering while moving ? Simple code.

TelKel81

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B4X: Copy
Sub AppStart (Form1 As Form, Args() As String)
    Form1.Show

    Dim ivSize As Int = 300
   
    Dim iv As ImageView
    iv.Initialize("")
    Form1.RootPane.AddNode(iv, 0, 0, ivSize, ivSize)
   
    Dim bc As BitmapCreator
    bc.Initialize(ivSize, ivSize)
    bc.DrawRect(bc.TargetRect, xui.Color_Red, False, 1)
    bc.SetBitmapToImageView(bc.Bitmap, iv)

    iv.SetLayoutAnimated(10000, 250, 250, ivSize, ivSize)
End Sub
 
I am not sure what you mean by 'moving'.

iv.SetLayoutAnimated(10000, 250, 250, ivSize, ivSize)

Your animation is set for 10 seconds. Is that what you really want?
 
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While the view is being moved by SetLayoutAnimated, the red borders are flickering. What I really want is no flickering :)
 
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That won't fix my issue when I'll start moving the view.

You get no flickering with the same code ?
 
Last edited:
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On my screen it is not exactly flickering. The animation seems to use fairly large steps, which makes a bit jerky.
It definitely isn't smooth.
 
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I tried a simpler view, with a similar effect, but not as severe.
B4X: Copy
    Dim pnlSize As Int = 300
    Dim pnl As B4XView = xui.CreatePanel("")
    pnl.SetColorAndBorder(xui.Color_Transparent, 1, xui.Color_Red, 0)
    Root.AddView(pnl, 0, 0, pnlSize, pnlSize)
    pnl.SetLayoutAnimated(10000, 250, 250, pnlSize, pnlSize)
 
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Jerky might be a better word to describe the issue. I'm french canadian so... :)

Here's a link to a clip of my problem (using my/your code).
 
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That's not good. I have created many draggable objects and I have never had a problem like this.
That's probably because I handle all the redrawing/refreshing myself. Clearly the image object requires more time to refresh.
Also, the BitmapCreator functions may be slower than the Canvas drawing or native View rendering.

Other community members may know what causes this. If anyone knows more about this please respond.
 
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