Authors CurseForge

writing up a button code for someone but i've hit a problem that i dont know how to fix, being a beginner.
here's the code

<Ui xmlns=<Ui xmlns="http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/FrameXML/UI.xsd">
    <Button name="NotepadButton" parent="UIParent" inherits="UIPanelButtonTemplate2" clampedToScreen="true" movable="true" text="BasicNotepad">
        <Size><AbsDimension x="50" y="25"/></Size>
    <Anchors>
        <Anchor point="CENTER">
        <Offset><AbsDimension x="0" y="0"/></Offset>
      </Anchor>
    </Anchors>
    <Scripts>
        <OnLoad>
          self:SetText("BNote");
          self:RegisterForDrag("LeftButton");
        </OnLoad>
      <OnClick>
             BasicNotepad.lua
      </OnClick>
	      <OnDragStart>self:StartMoving()</OnDragStart>
      <OnDragStop>self:StopMovingOrSizing()</OnDragStop>
      <OnEnter>
          GameTooltip:SetOwner(self, "ANCHOR_TOPLEFT");
        GameTooltip:SetText("Click to open BasicNotepad");
        GameTooltip:Show();
      </OnEnter>
      <OnLeave>
          GameTooltip:Hide();
      </OnLeave>
    </Scripts>
    </Button>
</Ui>

and the error

 line 21:
   Cannot find a library instance of "CallbackHandler-1.0".

I assume that i'm missing something in the code, but another addon I made with a very similar code works just fine.
all help is greatly appreciated

Quote from Torhal

You have to make sure CallbackHandler is being loaded from your AddOn's ToC file - before your code is loaded, as well.

i'll have to try that, thanks!

Quote from Felpalidan

i'll have to try that, thanks!

And fix your <OnClick>. You can't execute files like that. If you want to load it via XML, put <Script file="BasicNotepad.lua" /> outside the <Button>.

E.g.:

<UI ...>
    <Script file="BasicNotepad.lua" />
    <Button ...>
    ...
    </Button>
</Ui>

The very first line you posted has an obvious syntax error:

<Ui xmlns=[B][COLOR="Red"]<Ui xmlns=[/COLOR][/B]"http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/FrameXML/UI.xsd">

Also, your xsi:schemaLocation attribute's value is incorrect. It should include a linebreak, a .., and backslashes in the last section. See any XML file in the Blizzard UI for an example of a correct Ui tag for WoW:

<Ui xmlns="http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/
..\FrameXML\UI.xsd">

Also, this is not correct, and will not work, and will cause your entire XML file to fail:

      <OnClick>
             [B][COLOR="Red"]BasicNotepad.lua[/COLOR][/B]
      </OnClick>

If you want to load a Lua file from within an XML file, you must do it outside of any frame declarations, immediately after the Ui opening tag, using the Script tag:

<Ui xmlns="http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/
..\FrameXML\UI.xsd">
	[B][COLOR="#006600"]<Script file="BasicNotepad.lua"/>[/COLOR][/B]

But, as others have pointed out, the error message you posted has nothing to do with the code you posted. The game only displays errors originating from within Lua files.

Finally, you don't even need to use XML. The code you posted would be easier to read if rewritten in pure Lua, and you would get the added bonus of having detailed error messages when you did something wrong.

local button = CreateFrame("Button", "NotepadButton", UIParent, "UIPanelButtonTemplate2")
button:SetSize(50, 25)
button:SetPoint("CENTER")
button:SetText("BNote")

button:SetMovable(true)
button:SetClampedToScreen(true)
button:RegisterForDrag("LeftButton")
button:SetScript("OnDragStart", button.StartMoving)
button:SetScript("OnDragStop", button.StopMovingOrSizing)

button:SetScript("OnClick", function(self, mouseButton)
	-- paste your OnClick function here
end)

button:SetScript("OnEnter", function(self)
	GameTooltip:SetOwner(self, "ANCHOR_TOPLEFT")
	GameTooltip:SetText("Click to open BasicNotepad")
	GameTooltip:Show()
end)

button:SetScript("OnLeave", function(self)
	GameTooltip:Hide()
end)

Quote from Phanx

The very first line you posted has an obvious syntax error:

<Ui xmlns=[B][COLOR="Red"]<Ui xmlns=[/COLOR][/B]"http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/FrameXML/UI.xsd">

I can't believe we all missed that.