FormItem

所有超级接口:

FormBaseComponentIdProvider

所有已知子接口:

Cancel, DateChooser, FileElement, FormItemContainer, FormLink, FormMultipartItem, FormToggle, InlineElement, InlineIntegerElement, InlineTextElement, IntegerElement, MultipleSelectionElement, Reset, RichTextElement, SelectionElement, SingleSelection, SpacerElement, StaticTextElement, Submit, TextBoxListElement, TextElement

所有已知实现类:

AbstractTextElement, DateElement, FileElementImpl, FlexiTableElementImpl, FormCancel, FormItemImpl, FormLayoutContainer, FormLinkImpl, FormReset, FormSubmit, FormToggleImpl, IntegerElementImpl, JSDateChooser, MultipleSelectionElementImpl, MultiSelectionTree, RichTextElementImpl, SingleSelectionImpl, SpacerElementImpl, StaticTextElementImpl, TextAreaElementImpl, TextBoxListElementImpl, TextElementImpl
```
public interface FormItem
extends FormBaseComponentIdProvider
```
Summary:
setting panels content is optional and params can always be null
- setXyzKey(String i18nKey, String[] params)
- setErrorComponent(FormItem quickFixWizard)
accessing different panels within velocity of a form item:
- $r.render("formElementName_LABEL")
- $r.render("formElementName_ERROR")
- $r.render("formElementName_EXAMPLE")
find out about form item attributes by querying it from the velocity page with:
- $f.isMandatory("formElementName")
- $f.hasError("formElementName")
- $f.hasExample("formElementName")
- $f.hasLabel("formElementName")
whereas $f. is the FormDecorator instance in the velocity.

Description:
Each implemented form item consists of 4 panels appearing as div's in the html rendered page. They belong together in a logical way, but are layoutable, e.g. placeable anywhere within a velocity page. The following figure illustrates the logical composition.
- the Element panel
  The form element panel holds for example one or more checkboxes, a dropdownbox, an input field, ... any other html form element, a link!, a custom element!
- the Label panel
  textlabel for the element
- the Error panel
  Either a textlabel as error text or another form element. This form element can then start a subworkflow explaining the error or for fixing the error.
- the Example panel
  example text, explaing an input format or how to proceed with the shown element.
The following figure shows a concrete example of a yes-no switch, the form element is labeled "Depending on date". The screenshot is taken in debug mode mini which is available in development mode only. SingleSelectionImpl is the FormItem implemenation in this case.

The java code to create the above yes-no-switch looks as follows. Please note the anonymous class creation style, with a initializer block. This helps grouping the code:
- 519: dateSwitch is the name of the element in the velocity container
- 521/522: form.easy.dateSwitch is the i18n key for labeling, and the label is made visible.
- 523/524: sets the i18n keys for yes and no, and selects no as default
- 528: add an onclick listener, so you get informed if yes or no is clicked
- 529: final step of adding the form element to form (layout), it is then available in the velocity page layouting the form under the name dateSwitch
The form item goes to a velocity page under defined name, e.g. dateSwitch, and the corresponding logical panels are accessed with the following convention:
- form element name_LABEL
- form element name_ERROR
- form element name_EXAMPLE
It is very common that a layout needs information about whether a form item has an error, example, label or is mandatory. This information is available through a org.olat.presentation.framework.components.form.flexible.FormDecorator which can be accessed for example as $f.hasError("dateSwitch").
The FormItem is aggregated within FormItemContainer and both together form the composite pattern.
They play together with the Component and Container
Initial Date: 24.11.2006
作者:

patrickb

字段概要

字段
限定符和类型字段和说明

static java.lang.String ERRORC

static java.lang.String EXAMPLEC

static java.lang.String LABELC
- 从接口继承的字段 org.olat.presentation.framework.core.components.form.flexible.FormBaseComponentIdProvider
  DISPPREFIX

字段
限定符和类型	字段和说明
`static java.lang.String`	`ERRORC`
`static java.lang.String`	`EXAMPLEC`
`static java.lang.String`	`LABELC`

方法概要

方法
限定符和类型	方法和说明
`void`	`addActionListener(Controller listener, int events)`
`void`	`clearError()` error is resolved, e.g. hasError() should return false and the error component gets invisible (and resetted)
`void`	`doDispatchFormRequest(UserRequest ureq)` called if this component is dispatched, e.g. was clicked (double clicked, ...)
`void`	`evalFormRequest(UserRequest ureq)` called if just the form values must be remembered for the next render process.
`int`	`getAction()`
`java.util.List<java.lang.String>`	`getActionListenersFor(int event)`
`Component`	`getComponent()` The elements panel to be rendered by the GUI Framework.
`Component`	`getErrorC()` a complex "error" message, or a helper wizard to fix the error may be This method is used by a form infrastructure provider.
`java.lang.String`	`getErrorText()` This method is used by a form infrastructure provider.
`Component`	`getExampleC()` translated example text, wrapped in component This method is used by a form infrastructure provider.
`java.lang.String`	`getExampleText()` This method is used by a form infrastructure provider.
`Component`	`getLabelC()` label panel of the form item, `null` if no label provided/rendered This method is used by a form infrastructure provider.
`java.lang.String`	`getLabelText()` label panel of the form item, `null` if no label provided/rendered This method is used by a form infrastructure provider.
`java.lang.String`	`getName()` The form item's name within an manageing form container.
`Form`	`getRootForm()` a form item always has a root container where it belongs to.
`Translator`	`getTranslator()`
`java.lang.Object`	`getUserObject()`
`boolean`	`hasError()`
`boolean`	`hasExample()`
`boolean`	`hasFocus()` true if this element tries to get focus.
`boolean`	`hasLabel()`
`boolean`	`isEnabled()` true if item is marked as editable.
`boolean`	`isMandatory()` true if the form item should contain a (valid) value.
`boolean`	`isVisible()` true if form item was marked visible.
`void`	`reset()` reset the data in the field to a initial/predefined value.
`void`	`setEnabled(boolean isEnabled)` item is enabled/disabled, e.g. editable/read only in contrast to setVisible this does NOT DISABLE label, example, error!
`void`	`setErrorComponent(FormItem errorFormItem, FormLayouter container)` a complex "error" message, or a helper wizard to fix the error.
`void`	`setErrorKey(java.lang.String errorKey, java.lang.String... params)` Sets the i18n key for this form item's error message and displays the error message if showErro(true) is set.
`void`	`setExampleKey(java.lang.String exampleKey, java.lang.String[] params)` key for example with params to fill
`void`	`setFocus(boolean hasFocus)` true if the element should (try to) get focus, false is default
`void`	`setLabel(java.lang.String labelkey, java.lang.String[] params)` Key to be translated with the form translator and placed in the label panel.
`FormItem`	`setLabelComponent(FormItem labelComponent, FormItemContainer formLayout)` see setErrorComponent for comments
`void`	`setMandatory(boolean isMandatory)` Shows a mandatory icon next to this form item.
`void`	`setRootForm(Form rootForm)`
`void`	`setTranslator(Translator translator)`
`void`	`setUserObject(java.lang.Object userObject)`
`void`	`setVisible(boolean isVisible)` item, label, example, error get not visible
`void`	`showError(boolean show)`
`void`	`showExample(boolean show)`
`void`	`showLabel(boolean show)`
`void`	`validate(java.util.List<ValidationStatus> validationResults)` validate the data in the field, create error messages or update any component.

从接口继承的方法 org.olat.presentation.framework.core.components.form.flexible.FormBaseComponentIdProvider
getFormDispatchId

- 字段详细资料
  - ERRORC
```
static final java.lang.String ERRORC
```
    另请参阅:
    常量字段值
  - EXAMPLEC
```
static final java.lang.String EXAMPLEC
```
    另请参阅:
    常量字段值
  - LABELC
```
static final java.lang.String LABELC
```
    另请参阅:
    常量字段值
- 方法详细资料
  - evalFormRequest
```
void evalFormRequest(UserRequest ureq)
```
    called if just the form values must be remembered for the next render process. Do not validate data and create error messages.
    This method must be implemented by a specialised form item provider.
    
    参数:
    ureq -
    dispatchIDs -
    nextPos -
  - validate
```
void validate(java.util.List<ValidationStatus> validationResults)
```
    validate the data in the field, create error messages or update any component.
    This method must be implemented by a specialised form item provider.
  - reset
```
void reset()
```
    reset the data in the field to a initial/predefined value. This method is called if in a form a reset request is issued. It is the counterpart to the validate call which
  - setFocus
```
void setFocus(boolean hasFocus)
```
    true if the element should (try to) get focus, false is default
    
    参数:
    hasFocus -
  - hasFocus
```
boolean hasFocus()
```
    true if this element tries to get focus.
    
    返回:
  - doDispatchFormRequest
```
void doDispatchFormRequest(UserRequest ureq)
```
    called if this component is dispatched, e.g. was clicked (double clicked, ...)
    Please note, that the caller is not the GUI Framework but the form items manageing class. A default and exemplary implemention is Form.
    This method must be implemented by a specialised form item provider.
    
    参数:
    ureq -
    dispatchIDs -
    nextPos -
  - getName
```
java.lang.String getName()
```
    The form item's name within an manageing form container. This has nothing to do with a name displayed on the screen to the user.
    The default implementation FormItemImpl uses the name to make the element available in the velocity container.
    This method is used by a form infrastructure provider.
    
    返回:
  - getComponent
```
Component getComponent()
```
    The elements panel to be rendered by the GUI Framework.
    
    返回:
  - getRootForm
```
Form getRootForm()
```
    a form item always has a root container where it belongs to. The root container is responsible for the opening and closing HTML FORM tag.
    This method must be implemented by a specialised form item provider.
    
    返回:
  - getLabelC
```
Component getLabelC()
```
    label panel of the form item, null if no label provided/rendered
    This method is used by a form infrastructure provider.
    
    返回:
  - getLabelText
```
java.lang.String getLabelText()
```
    label panel of the form item, null if no label provided/rendered
    This method is used by a form infrastructure provider.
    
    返回:
  - setLabel
```
void setLabel(java.lang.String labelkey,
            java.lang.String[] params)
```
    Key to be translated with the form translator and placed in the label panel.
    
    参数:
    labelkey - i18n key
    params - i18n key parameters
  - setLabelComponent
```
FormItem setLabelComponent(FormItem labelComponent,
                         FormItemContainer formLayout)
```
    see setErrorComponent for comments
    
    参数:
    labelComponent -
    layout -
  - isMandatory
```
boolean isMandatory()
```
    true if the form item should contain a (valid) value.
    
    返回:
  - setMandatory
```
void setMandatory(boolean isMandatory)
```
    Shows a mandatory icon next to this form item. This is only a GUI cue, it does not activate any validators. It is in the developer's responsibility to validate the form.
    
    参数:
    isMandatory - Whether this form item should have a mandatory icon.
  - setErrorKey
```
void setErrorKey(java.lang.String errorKey,
               java.lang.String... params)
```
    Sets the i18n key for this form item's error message and displays the error message if showErro(true) is set.
    
    参数:
    errorKey - i18n key for the error message.
    params - Additional error message contents.
  - setErrorComponent
```
void setErrorComponent(FormItem errorFormItem,
                     FormLayouter container)
```
    a complex "error" message, or a helper wizard to fix the error.
    It must be a form item itself, that starting the fixing workflow let the surrounding form evaluate (intermediate save values).
    Typically a FormLink is used here to start a workflow in a modal dialog.
    Use showError(true) for the visibility of the error.
    
    参数:
    errorFormItem -
    container - the container containing the form item which has the error
  - getErrorC
```
Component getErrorC()
```
    a complex "error" message, or a helper wizard to fix the error may be
    This method is used by a form infrastructure provider. null
  - getErrorText
```
java.lang.String getErrorText()
```
    This method is used by a form infrastructure provider.
    
    返回:
  - getExampleC
```
Component getExampleC()
```
    translated example text, wrapped in component
    This method is used by a form infrastructure provider.
    
    返回:
  - getExampleText
```
java.lang.String getExampleText()
```
    This method is used by a form infrastructure provider.
    
    返回:
  - setExampleKey
```
void setExampleKey(java.lang.String exampleKey,
                 java.lang.String[] params)
```
    key for example with params to fill
    
    参数:
    exampleKey - , null to clear example
    params - , may be null
  - setTranslator
```
void setTranslator(Translator translator)
```
    参数:
    translator -
  - getTranslator
```
Translator getTranslator()
```
    返回:
  - setVisible
```
void setVisible(boolean isVisible)
```
    item, label, example, error get not visible
    
    参数:
    isVisible -
  - isVisible
```
boolean isVisible()
```
    true if form item was marked visible.
  - setEnabled
```
void setEnabled(boolean isEnabled)
```
    item is enabled/disabled, e.g. editable/read only in contrast to setVisible this does NOT DISABLE label, example, error!
    
    参数:
    isEnabled -
  - isEnabled
```
boolean isEnabled()
```
    true if item is marked as editable.
    
    返回:
  - hasError
```
boolean hasError()
```
    返回:
  - hasLabel
```
boolean hasLabel()
```
    返回:
  - hasExample
```
boolean hasExample()
```
    返回:
  - setRootForm
```
void setRootForm(Form rootForm)
```
    参数:
    rootForm -
  - showLabel
```
void showLabel(boolean show)
```
    参数:
    show -
  - showError
```
void showError(boolean show)
```
    参数:
    show -
  - clearError
```
void clearError()
```
    error is resolved, e.g. hasError() should return false and the error component gets invisible (and resetted)
  - showExample
```
void showExample(boolean show)
```
    参数:
    show -
  - addActionListener
```
void addActionListener(Controller listener,
                     int events)
```
    参数:
    listener -
    events -
  - getActionListenersFor
```
java.util.List<java.lang.String> getActionListenersFor(int event)
```
    参数:
    event -
    
    返回:
  - getAction
```
int getAction()
```
    返回:
  - setUserObject
```
void setUserObject(java.lang.Object userObject)
```
    参数:
    userObject -
  - getUserObject
```
java.lang.Object getUserObject()
```
    返回:

接口 FormItem

Summary:

Description:

字段概要

从接口继承的字段 org.olat.presentation.framework.core.components.form.flexible.FormBaseComponentIdProvider

方法概要

从接口继承的方法 org.olat.presentation.framework.core.components.form.flexible.FormBaseComponentIdProvider

字段详细资料

ERRORC

EXAMPLEC

LABELC

方法详细资料

evalFormRequest

validate

reset

setFocus

hasFocus

doDispatchFormRequest

getName

getComponent

getRootForm

getLabelC

getLabelText

setLabel

setLabelComponent

isMandatory

setMandatory

setErrorKey

setErrorComponent

getErrorC

getErrorText

getExampleC

getExampleText

setExampleKey

setTranslator

getTranslator

setVisible

isVisible

setEnabled

isEnabled

hasError

hasLabel

hasExample

setRootForm

showLabel

showError

clearError

showExample

addActionListener

getActionListenersFor

getAction

setUserObject

getUserObject