XAF Application Development Tutorial (vii) Appearance control module

Many times, we need to show different effects according to different conditions, in traditional software development, we will directly use the name of the control. Backcolor,enable,visible, and other attributes are controlled.

If a business object is used in multiple places, either we will go to a place where a change is made, or the code will be centralized to do a method of control.

In Xaf, a method of controlling global effectiveness is implemented.

Let's take a look at the façade module:

Several effects are shown: 1, the entire line of red background. 2, blue font plus strikethrough. 3 edit-time control is disabled. 4. Cell color change.

In the detailed interface, the same takes effect, above two pictures, one is web, one WinForm.

Below we show how to make the same effect:

[Defaultclassoptions]//[ImageName ("Bo_contact")]//[Defaultproperty ("Displaymembernameforlookupeditorsofthistype")]//[Defaultlistviewoptions (Masterdetailmode.listviewonly, False, Newitemrowposition.none)]//[Persistent ("Databasetablename")]//specify more UI options using a declarative approach (https://documentation.devexpress.com/eXpressAppFramework/CustomDocument112701.aspx).[Appearance ("Red Disabled","ViewItem", BackColor ="Red", Targetitems ="*", Criteria ="Disabled")] [Appearance ("Blue not approved","ViewItem", BackColor ="Blue", Targetitems ="*", Criteria ="! Audited")]     Public classclient: baseobject {

Write two appearance attribute on the customer class.

First look at the effect:

A very simple two statement has the effect, click into the Detailed view, it is also effective.

Let's go to Xafml and look at the appearance rules:

It looks much easier to understand than the code below, but the XAF developers are accustomed to writing rules in code, which is faster, or switching to XAFML, writing code, and setting up Xafml is annoying enough.

So our choice is the legendary code first congestion model.

Here's a look at the functionality of each of the properties:

Appearanceitemtype: Items to control

	Value	description
	Action	To control is the button
	Layoutitem	The name of the layout item used in the detailed interface
	ViewItem	Can be simply understood as the name of the property, in the detailed view in addition to the property will generate corresponding ViewItem, but also can be manually set up such as static text, static image class ViewItem, of course those are also within the control range.

Context:

Optional Values	appearance Rule ' s Activity Scope	Example
Built-in three types of DetailView ListView any.	Detailed view, List view, or all views.	Any
The specified view ID	Only takes effect on the specified view.	Myclass_listview; Myclass_detailview
Any; view name	All views, except for the view names listed after any	any; Myclass_listview; Myclass_lookuplistview
"DetailView" or "ListView" followed by the view name.	All list views, and the specified view	DetailView; Myclass_listview

Criteria: Effective When the specified conditions are met, such as age >20

Method: The rule will not take effect until the specified method returns a true value, such as:

usingDevExpress.ExpressApp.ConditionalAppearance;//... Public classProduct:baseobject { PublicProduct (Session session):Base(session) {} Public decimalPrice {//...    }     Publicproductstatus Status {//...} [Appearance ("Rulemethod", Appearanceitemtype ="ViewItem", Targetitems ="*", Context ="ListView", BackColor="Green", FontColor ="Black")]     Public BOOLRulemethod () {if(Price <Ten&& Status = =productstatus.active) {return true; }        Else {            return false; }    }}

Priority: If more than one rule is applied to the same element, it will be determined by that priority which will take effect and the higher the value the greater the precedence.

Targetitems:

Example	Description
"Targetelementid" target element ID	For example, fill in the name of the property, Layoutitem name
"TARGETELEMENTID1; TargetElementId2 "	IDs of multiple elements, separated by semicolons
"*"	All elements
"*; TARGETELEMENTID1; TargetElementId2 "	All elements, except for the specified element following the * number

BackColor: Background color

Enable: If the specified Viewitem,layoutitem is an allegation that the item is available. If it is a button, it refers to whether it can be clicked.

FontColor: Font Color

FontStyle: Font styles, such as bold, strikethrough, and so on.

Visibility: Is visible.

The following table shows the environments in effect:

Personalization	List Cells	List Edit mode	Detailed View	Detailed View static text	Layout Items	Layout group, TAB	Button
Font Color
Font Style
Back Color
Enabled/disabled
Visible/invisible

For example, in the list, visible control, a list has a lot of rows so there must be no way to do some of the contents of the line is hidden, some of the contents of the line is visible.

Appearance's function is described here.

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XAF Application Development Tutorial (vii) Appearance control module