screen widget 框架页面生成原理初探

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screen widget 本质是基于freemarker 的。目前screen类型的view基本都是MacroScreenViewHandler.java 负责处理的。

MacroScreenViewHandler.java render 方法中首先通过配置文件加载了三个类库。如下

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ScreenStringRenderer screenStringRenderer =newMacroScreenRenderer(UtilProperties.getPropertyValue("widget", getName() +".name"), UtilProperties.getPropertyValue("widget", getName() +".screenrenderer")); 
FormStringRenderer formStringRenderer =newMacroFormRenderer(UtilProperties.getPropertyValue("widget", getName() +".formrenderer"), request, response); 
TreeStringRenderer treeStringRenderer =newMacroTreeRenderer(UtilProperties.getPropertyValue("widget", getName() +".treerenderer"), writer); 

正式render 页面前后，利用freemarker 编译了两个宏指令

screenStringRenderer.renderScreenBegin(writer, screens.getContext());            screens.render(page);            screenStringRenderer.renderScreenEnd(writer, screens.getContext());

public void renderScreenBegin(Appendable writer, Map<String, Object> context) throws IOException {         executeMacro(writer, "renderScreenBegin", null);     }       public void renderScreenEnd(Appendable writer, Map<String, Object> context) throws IOException {         executeMacro(writer, "renderScreenEnd", null);     }

宏指令定义为

<#macro renderScreenBegin>  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">  </#macro>    <#macro renderScreenEnd>  </#macro>

screen widget 大概处理过程。获取screnn 第一个section ，解析处理action（预处理所需数据）condition，根据condition结果决定处理子widget是widget还是fail-widget 。子widget的处理过程和上层widget类似。如此深入。具体的没有嵌套的screen widget 可以使用上述freemarker 类库来编译成html。

screen widget 本质是基于freemarker 的。目前screen类型的view基本都是MacroScreenViewHandler.java 负责处理的。

MacroScreenViewHandler.java render 方法中首先通过配置文件加载了三个类库。如下

?
ScreenStringRenderer screenStringRenderer =newMacroScreenRenderer(UtilProperties.getPropertyValue("widget", getName() +".name"), UtilProperties.getPropertyValue("widget", getName() +".screenrenderer")); 
FormStringRenderer formStringRenderer =newMacroFormRenderer(UtilProperties.getPropertyValue("widget", getName() +".formrenderer"), request, response); 
TreeStringRenderer treeStringRenderer =newMacroTreeRenderer(UtilProperties.getPropertyValue("widget", getName() +".treerenderer"), writer); 

正式render 页面前后，利用freemarker 编译了两个宏指令

screenStringRenderer.renderScreenBegin(writer, screens.getContext());            screens.render(page);            screenStringRenderer.renderScreenEnd(writer, screens.getContext());

public void renderScreenBegin(Appendable writer, Map<String, Object> context) throws IOException {         executeMacro(writer, "renderScreenBegin", null);     }       public void renderScreenEnd(Appendable writer, Map<String, Object> context) throws IOException {         executeMacro(writer, "renderScreenEnd", null);     }

宏指令定义为

<#macro renderScreenBegin>  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">  </#macro>    <#macro renderScreenEnd>  </#macro>

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