Again, thank you so much for the help! The head merge feature is perfect for this situation i described and my next line of though is right inline with how you describe bind points!
Thanks again! -- Martin On Mon, Mar 8, 2010 at 12:47 PM, Ross Mellgren <[email protected]> wrote: > For your particular example, you can use head merge as Naftoli suggests. > Head merge is a behavior of Lift templates where any <head> tags will be > merged together for the final output, so you put your meta > name="description" in each of the specific places, any general head stuff > you want in your surrounding template and they will magically get folded > together at render time. > > For other cases, you have a couple tools at your disposal: > - RequestVars -- variables that are local to a particular page request. > You can use these inside snippets to capture and recover values during > template processing. > - Bind points. In a surrounding template you can use tags like <lift:bind > name="foobar" /> and then define what to put there in the surrounded > template using <lift:bind-at name="foobar">the content</lift:bind-at> > > And there are more. Hopefully head merging will work for you in this case. > > -Ross > > On Mar 7, 2010, at 8:25 PM, Martin Dale Lyness wrote: > > Thank you Ross, for the very informative response! > > Now, I consider SEO to be closer to a designer task than a developer task > so keeping the power in the design documents would be my best idea. Is there > anyway to allow individual pages to define blocks that are read into the > snippets and then injected into the template? > > Here is the scenario i'm thinking of: > 1. A single uniform website template: default.html > 2. Several HTML files: index.html, product_list.html, product_overview.html > 3. Each of these HTML files containing <lift:xxx> tags referencing > snippets. > > What i would want is for index.html, product_list.html, and > product_overview.html to all use default.html and various Snippet classes. > Now for SEO i would want the meta tags in the header of default.html to be > customized to index.html, product_list.html, and product_overview.html; > furthermore, product_list and product_overview are dynamic pages so they > would need further customization based on what the snippets are returning. > > Essentially, i would want tags something like: > <lift:meta_desc>This site is totally awesome, better than all our > competitors</lift:meta_desc> in index.html > <lift:meta_desc>Look at all these products in > %%category_name%%</lift:meta_desc> in product_list.html > <lift:meta_desc>%product_name% - %product_description%</lift:meta_desc> > in product_overview.html > > The conceptual road block for me is coming from the controller first > pattern used in frameworks like Rails. In lift snippets are not really the > same conceptually. If i use the second proposed method > (i.e. <lift:HelloWorld.hello> wrapping the entire template) i would have a > battle between snippets used by each page. For example, perhaps i have a > product overview snippet that sets the meta one way and a login snippet that > sets it another way (intended for when show standalone in a login.html). > > The first solution with using a <lift:HelloWorld.funcName /> to inject a > snippet at a meta location fits better because it would allow me to create a > generic function that would attempt to create the keyword and description > data based on whatever global information is made available to snippets by > lift (i.e. Request Parameters?). My only problem with using this option is > it puts all of the text on the developer side forcing the dev team to update > descriptions and keywords where really the designers should be doing this. > > Does anyone have a suggestion on how to put the power in the hands of the > designers in this type of situation? > > -- Martin > > On Sun, Mar 7, 2010 at 6:17 PM, Ross Mellgren <[email protected]> wrote: > >> To be parsed by the bind, it must be enclosed by >> <lift:HelloWorld.hello>...</lift:HelloWorld.hello> >> >> There is relatively little magic -- Lift goes through your template >> looking for lift: prefixed tags. For those tags, it will look up a snippet >> class by using the part before the period (HelloWorld, in the above example) >> and then look for a method on that snippet class mentioned after the period >> (hello in the example). If there is no period, the method is assumed to be >> called "render". >> >> Once that method is found, the method is called with the contents of the >> lift: tag, and the result of the method call is spliced into the XML to >> replace the lift: tag. >> >> bind is a function that does something kind of similar to overall template >> processing, except you supply some prefix other than lift: (b: in the >> example) and a limited set of things after the colon that are valid (time >> and meta_desc in the example) >> >> So, you might want something like this instead: >> >> <meta name="description"><lift:HelloWorld.meta_desc /></meta> >> >> class HelloWorld { >> .... >> def meta_desc(ns: NodeSeq): NodeSeq = Text("test desc") >> .... >> } >> >> Which will result in this XHTML: >> >> <meta name="description">test desc</meta> >> >> Or, if you want to keep it in the hello method, you'd then have to move >> the <lift:HelloWorld.hello> to the outside of the template: >> >> <lift:HelloWorld.hello> >> ... >> <head> >> <meta name="description"><b:meta:desc /></meta> >> </head> >> ... >> <b:time /> >> </lift:HelloWorld.hello> >> >> Hope that helps, >> -Ross >> >> >> On Mar 7, 2010, at 4:38 AM, Martin wrote: >> >> > How would one go about having dynamic description and keyword meta >> > tags in a template? Here is what i've tried: >> > >> > default.html >> > <meta name="description"><b:meta_desc /></meta> >> > >> > HelloWorld.scala >> > Helpers.bind("b", in, "time" -> date.map(d => Text(d.toString)), >> > "meta_desc" -> "test desc") >> > >> > I'm using a basic archetype build of 2.0-M3 and it produces an error: >> > >> > This page contains the following errors: >> > >> > error on line 6 at column 28: Namespace prefix b on meta_desc is not >> > defined >> > Below is a rendering of the page up to the first error. >> > >> > >> > It appears to me that the template is not parsed by the Helpers.bind, >> > is this correct? >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups "Lift" group. >> > To post to this group, send email to [email protected]. >> > To unsubscribe from this group, send email to >> [email protected]<liftweb%[email protected]> >> . >> > For more options, visit this group at >> http://groups.google.com/group/liftweb?hl=en. >> > >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Lift" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]<liftweb%[email protected]> >> . >> For more options, visit this group at >> http://groups.google.com/group/liftweb?hl=en. >> >> > > -- > You received this message because you are subscribed to the Google Groups > "Lift" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/liftweb?hl=en. > > > -- > You received this message because you are subscribed to the Google Groups > "Lift" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<liftweb%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/liftweb?hl=en. > -- You received this message because you are subscribed to the Google Groups "Lift" group. 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