Roku Developer Program

[Biggytv]

Another questions about Canvas updates.

I setup the canvas and do a url call to json data. I would like to then call the json every 10 seconds to update the layer text.

This question also applies to updating the associate ScreenSaver info.

Here is the Setup of the canvas

Function SetupFramedCanvas()
    m.canvas.AllowUpdates(true)
    m.canvas.Clear()
    m.canvas.SetLayer(0, [
        { 'Background:
            Url: m.background
            CompositionMode: "Source"
        },
        
    ])
    m.paint()
End Function

Here is my original call:

Function PaintFramedCanvas()
    jsonRequest = CreateObject("roUrlTransfer")
    jsonRequest.SetURL("http://URLTOJSON")
    guide = ParseJson(jsonRequest.GetToString())
    print "Album art: "+guide.album_art.src
    print guide

    list = []
    mode = CreateObject("roDeviceInfo").GetDisplayMode()
'    print "m.streamPlaying: "+m.streamPlaying
    print m.progress
    if m.progress < 95
        list.Push({
            Color: "#000000"
            TargetRect: { x: 75, y: 475, w: 200, h: 100 }
        })
        list.Push({
            Text: "Loading..." + m.progress.tostr() + "%"
            TargetRect: { x: 75, y: 475, w: 200, h: 100 }
        })
    else  'Audio is currently playing
        if m.paused
            list.Push({
             Color: "#ffffff"
            TargetRect: { x: 75, y: 475, w: 200, h: 100 }
            CompositionMode: "Source"
            })
            if mode = "720p"
                list.Push({
                    url: "pkg:/images/pause_icon_small.png"
            TargetRect: { x: 75, y: 475, w: 100, h: 50 }
                })
            else
                list.Push({
                    url: "pkg:/images/pause_icon_small.png"
            TargetRect: { x: 75, y: 475, w: 100, h: 50 }
                })
            end if
        else if m.overlay
            list.Push({
                Color: "#ffffff"
            TargetRect: { x: 75, y: 475, w: 200, h: 100 }
                CompositionMode: "Source"
            })
        else  'not paused
            list.Push({
                Color: "#ffffff"
            TargetRect: { x: 75, y: 475, w: 200, h: 100 }
                CompositionMode: "Source"
            })
        end if
 
       if guide.album_art.src = ""
       imageUrl = ""
       imageRect = ""
       else
       imageUrl = "http://URLTOSTREAMARTWORK?u="+guide.album_art.src+""
       imageRect = { x: 55, y: 256, w: 180, h: 180 }
       end if
'****MetaData
        if mode = "720p"
           list.Push({
                url: imageUrl
                TargetRect: imageRect
            })
            list.Push({
                Text: "Title: "+guide.title
                TargetRect: { x: 350, y: 225, w: 430, h: 90 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Album: "+guide.album
                TargetRect: { x: 350, y: 325, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Artist: "+guide.artist
                TargetRect: { x: 350, y: 425, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
           
        else
            list.Push({
                Text: "Nu"
                TargetRect: { x: 443, y: 132, w: 50, h: 55 }
                TextAttrs: { font: "s", halign: "right", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.title
                TargetRect: { x: 499, y: 132, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.artist
                TargetRect: { x: 443, y: 193, w: 50, h: 55 }
                TextAttrs: { font: "s", halign: "right", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.album
                TargetRect: { x: 499, y: 193, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })

        end if
    end if
    m.canvas.SetLayer(1, list)
    
End Function

Here is the Function to update the Canvas Layer Text

Function UpdateCanvas()

    print "Updating 60 seconds"
    list = []
    mode = CreateObject("roDeviceInfo").GetDisplayMode()

    jsonRequest = CreateObject("roUrlTransfer")
    jsonRequest.SetURL("http://URLTOJSON")
    guide = ParseJson(jsonRequest.GetToString())
    print "Album art: "+guide.album_art.src
    print guide
    print "Update Canvas Request"

       if guide.album_art.src = ""
       imageUrl = ""
       imageRect = ""
       else
       imageUrl = "http://URLTOARTWORK?u="+guide.album_art.src+""
       imageRect = { x: 55, y: 256, w: 180, h: 180 }
       end if
'****MetaData
        if mode = "720p"
           list.Push({
                url: imageUrl
                TargetRect: imageRect
            })
            list.Push({
                Text: "Title: "+guide.title
                TargetRect: { x: 350, y: 225, w: 430, h: 90 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Album: "+guide.album
                TargetRect: { x: 350, y: 325, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Artist: "+guide.artist
                TargetRect: { x: 350, y: 425, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
           
        else
                     list.Push({
                Text: guide.title
                TargetRect: { x: 499, y: 132, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.artist
                TargetRect: { x: 443, y: 193, w: 50, h: 55 }
                TextAttrs: { font: "s", halign: "right", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.album
                TargetRect: { x: 499, y: 193, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })

        end if
    m.canvas.SetLayer(1, list)

End Function

Here is my Event Loop

Function EventLoop()
timer=createobject("rotimespan")
timer.mark()

    while true
        msg = wait(0, m.port)
        if msg <> invalid
            'If this is a startup progress status message, record progress
            'and update the UI accordingly:
            if msg.isStatusMessage() and msg.GetMessage() = "startup progress"
                m.paused = false
                progress% = msg.GetIndex() / 10
                if m.progress <> progress%
                    m.progress = progress%
                    m.paint()
                    print m.progress
                end if
             

             else if timer.totalseconds() > 3 
                   'result=UpdateCanvas()
                   'print result
                UpdateCanvas()
              
              


            'Playback progress (in seconds):

            'If the <UP> key is pressed, jump out of this context:
            else if msg.isRemoteKeyPressed()
                index = msg.GetIndex()
                print "Remote button pressed: " + index.tostr()
                if index = 4 '<left>
                    return -1

                else if index = 13  '<PAUSE/PLAY>
                    if m.paused m.player.Resume() else m.player.Pause()
                end if

            else if msg.isPaused()
                m.paused = true
                m.paint()

            else if msg.isResumed()
                m.paused = false
                m.paint()
            end if
            'Output events for debug

            print msg.GetType(); ","; msg.GetIndex(); ": "; msg.GetMessage()
            if msg.GetInfo() <> invalid print msg.GetInfo();
            end if



    end while
End Function

Any direction for correcting my code is appreciated.

[RokuMarkn]

Well, the wait(0) should have a nonzero timeout, so that your code has a chance to check the timer even if no events arrive. Also, the check for the timer should not be inside the "msg <> invalid" block, since the message WILL be invalid when the wait returns due to a timeout.

--Mark

[Biggytv]

Thanks Mark.

My update call is being made on the timer without issue. The error message when I try to update the Layer refers to m.canvas.SetLayer(1, list) in the UpdateCanvas().

The error message is: Interface not a member of BrightScript Component

So I am not clear why the error when my initial PaintedFrameCanvas() worked fine.

[Biggytv]

So my timespan is working in my eventloop and I am getting the new calls to json on a timed basis I can see the new information in debug, but I can't seem to figure out how to push the updates to the Canvas Layer with the new Json information.

What am I missing regarding updating the Canvas Layer? :x :?:

Here is my code:

Function UpdateCanvas()

    jsonRequest = CreateObject("roUrlTransfer")
    jsonRequest.SetURL("http://ltr.streamon.fm/card")
    guide = ParseJson(jsonRequest.GetToString())
    print "Album art: "+guide.album_art.src
    print guide
    
    m.canvas.Clear()
    m.canvas.SetLayer(0, [
        { 'Background:
            Url: m.background
            CompositionMode: "Source"
        },
        
    ])
    m.paint()
        
    list = []
    mode = CreateObject("roDeviceInfo").GetDisplayMode()
    
    
       if guide.album_art.src = ""
       imageUrl = ""
       imageRect = ""
       else
       imageUrl = "http://www.streamon.fm/player/getAlbumArt.php?u="+guide.album_art.src+""
       imageRect = { x: 55, y: 256, w: 180, h: 180 }
       end if
'****MetaData

        if mode = "720p"
           list.Push({
                url: imageUrl
                TargetRect: imageRect
            })
            list.Push({
                Text: "Title: "+guide.title
                TargetRect: { x: 350, y: 225, w: 430, h: 90 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Album: "+guide.album
                TargetRect: { x: 350, y: 325, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: "Artist: "+guide.artist
                TargetRect: { x: 350, y: 425, w: 430, h: 80 }
                TextAttrs: { font: "small", halign: "left", valign: "center", color: m.textcolor }
            })
           
        else
            list.Push({
                Text: guide.title
                TargetRect: { x: 499, y: 132, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.artist
                TargetRect: { x: 443, y: 193, w: 50, h: 55 }
                TextAttrs: { font: "s", halign: "right", valign: "center", color: m.textcolor }
            })
            list.Push({
                Text: guide.album
                TargetRect: { x: 499, y: 193, w: 193, h: 55 }
                TextAttrs: { font: "s", halign: "left", valign: "center", color: m.textcolor }
            })

        end if

    m.canvas.SetLayer(1, list)

End Function

[Biggytv]

I moved the refresh to the EventLoop and it is work now.

Thanks!