IlvLabelLayoutLabelProperty (Perforce JViews 10.0 API)

java.lang.Object
- ilog.views.IlvNamedProperty
- - ilog.views.graphlayout.labellayout.IlvLabelLayoutLabelProperty

All Implemented Interfaces:

IlvPersistentObject, Serializable

Direct Known Subclasses:

IlvAnnealingLabelLayoutLabelProperty
```
public class IlvLabelLayoutLabelProperty
extends IlvNamedProperty
```
The class IlvLabelLayoutLabelProperty allows you to store the settings of an instance of IlvLabelLayout for an individual label as a named property in the label. This is used by IlvDefaultLabelingModel.saveParametersToNamedProperties(IlvLabelLayout, boolean) which is an auxiliary to be used before IlvManager.write(IlvOutputStream) if you want to store layout parameter settings in .ivl files.
If you create your own subclass of IlvLabelLayout and want to save the layout parameters of your subclass for individual labels in .ivl files, you need to create a subclass of this class. The subclass must provide a constructor with your IlvLabelLayout subclass and the label as input, and transfer the layout parameters of the label from the input layout to the property. It must also override the transfer method to transfer the layout parameters from the property back to the layout instance.
Further information about subclassing can be found in the documentation of IlvNamedProperty.
As an example, assume that your subclass MyLayout of IlvLabelLayout has a string parameter for each label that can be accessed by getMyParameter and set by setMyParameter. You can create a named property that can store this parameter in the following way:
```
 public class MyLayoutLabelProperty extends IlvLabelLayoutLabelProperty
 { 
  String myParameter;
 
  public MyLayoutLabelProperty(
    String name, MyLayout layout, IlvGraphic label, boolean withDefaults)
  {
    super(name, layout, label, withDefaults);
    this.myParameter = layout.getMyParameter(label);
  }

  public MyLayoutLabelProperty(MyLayoutLabelProperty source)
  {
    super(source);
    this.myParameter = source.myParameter;
  }
 
  public MyLayoutLabelProperty(IlvInputStream stream)
    throws IOException, IlvReadFileException
  {
    super(stream);
    try {
      this.myParameter = stream.readString("myParameter");
    } catch (IlvFieldNotFoundException e) {
      this.myParameter = myParameterDefaultValue;
    }
  } 

  public IlvNamedProperty copy()
  {
    return new MyLayoutLabelProperty(this);
  }

  public void write(IlvOutputStream stream) throws IOException
  {
    super.write(stream);
    stream.write("myParameter", this.myParameter);
  }

  public void transfer(IlvLabelLayout layout, IlvGraphic label)
  {
    super.transfer(layout, label);
    ((MyLayout)layout).setMyParameter(label, this.myParameter);
  }

  public boolean isPersistent()
  {
    // this will catch the case that omitDefaults is false
    if (super.isPersistent())
      return true;

    // in case omitDefaults is true:
    if (this.myParameter != myParameterDefaultValue)
      return true;
    return false;
  }
 }
 
```
Note that MyLayout must override IlvLabelLayout.createLayoutLabelProperty(String, IlvGraphic, boolean) to return an instance of your new class MyLayoutLabelProperty.
Since:

JViews 5.0

See Also:

IlvDefaultLabelingModel.saveParametersToNamedProperties(IlvLabelLayout, boolean), IlvDefaultLabelingModel.loadParametersFromNamedProperties(IlvLabelLayout), IlvDefaultLabelingModel.removeParametersFromNamedProperties(), Serialized Form

Constructor Summary

Constructors
Constructor and Description
`IlvLabelLayoutLabelProperty(IlvInputStream stream)` Creates a new `IlvLabelLayoutLabelProperty` from an `IlvInputStream`.
`IlvLabelLayoutLabelProperty(IlvLabelLayoutLabelProperty source)` Creates a new `IlvLabelLayoutLabelProperty` by copying an existing one.
`IlvLabelLayoutLabelProperty(String name, IlvLabelLayout layout, IlvGraphic label, boolean withDefaults)` Creates a new `IlvLabelLayoutLabelProperty` that stores layout parameter settings of the `layout` for the `label`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`IlvNamedProperty`	`copy()` Copies the named property.
`void`	`dispose(IlvDefaultLabelingModel model)` Disposes of the property and releases any resources that it is using.
`protected IlvLabelLayout`	`getLayout()` Returns the layout instance that created this property.
`boolean`	`isPersistent()` Returns `true` if the property must be saved to an `.ivl` file.
`protected boolean`	`isWritten(IlvGraphic label)` Returns `true` if the writing of the input label was completed.
`protected boolean`	`omitDefaults()` Returns `true` if the layout property is not persistent when all stored parameter values are default values.
`void`	`transfer(IlvLabelLayout layout, IlvGraphic label)` Transfers the layout parameter settings stored in this named property back to the input layout for the input label.
`void`	`write(IlvOutputStream stream)` Writes the property to the output stream.

Methods inherited from class ilog.views.IlvNamedProperty
getName

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - IlvLabelLayoutLabelProperty
```
public IlvLabelLayoutLabelProperty(String name,
                                   IlvLabelLayout layout,
                                   IlvGraphic label,
                                   boolean withDefaults)
```
    Creates a new IlvLabelLayoutLabelProperty that stores layout parameter settings of the layout for the label.
    
    Parameters:
    
    name - The name of the property.
    
    layout - The layout instance to be stored.
    
    label - The label whose layout parameters are to be stored.
    
    withDefaults - If true, the layout property is always persistent. If false, it is persistent only if nondefault parameter settings exist (that is, if the the property is saved to an .ivl file, the default parameter settings are not saved).
  - IlvLabelLayoutLabelProperty
```
public IlvLabelLayoutLabelProperty(IlvLabelLayoutLabelProperty source)
```
    Creates a new IlvLabelLayoutLabelProperty by copying an existing one.
    
    Parameters:
    
    source - The origin of the copy.
  - IlvLabelLayoutLabelProperty
```
public IlvLabelLayoutLabelProperty(IlvInputStream stream)
                            throws IOException,
                                   IlvReadFileException
```
    Creates a new IlvLabelLayoutLabelProperty from an IlvInputStream.
    
    Parameters:
    
    stream - The input stream from which the property must be read.
    
    Throws:
    
    IlvReadFileException - if an error occurs while reading.
    
    IOException
- Method Detail
  - getLayout
```
protected IlvLabelLayout getLayout()
```
    Returns the layout instance that created this property. If the property was created by reading from IlvInputStream, it returns null.
  - omitDefaults
```
protected boolean omitDefaults()
```
    Returns true if the layout property is not persistent when all stored parameter values are default values. Returns false if the layout property is persistent independent of default values. If the property was created by reading from IlvInputStream, it returns false.
  - copy
```
public IlvNamedProperty copy()
```
    Copies the named property.
    
    Specified by:
    
    copy in class IlvNamedProperty
  - isPersistent
```
public boolean isPersistent()
```
    Returns true if the property must be saved to an .ivl file.
    
    Specified by:
    
    isPersistent in class IlvNamedProperty
  - isWritten
```
protected boolean isWritten(IlvGraphic label)
```
    Returns true if the writing of the input label was completed.
    If customers need to subclass this class, this auxiliary can be used inside the implementation of the write method only. For instance, it can be used if information must be written depending on whether another label has already been written.
    
    Parameters:
    
    label - A label of the same manager.
    
    Returns:
    
    true if the label has been written before this property.
    
    See Also:
    
    write(IlvOutputStream)
  - write
```
public void write(IlvOutputStream stream)
           throws IOException
```
    Writes the property to the output stream.
    
    Specified by:
    
    write in interface IlvPersistentObject
    
    Overrides:
    
    write in class IlvNamedProperty
    
    Parameters:
    
    stream - The output stream.
    
    Throws:
    
    IOException - standard IO error.
  - transfer
```
public void transfer(IlvLabelLayout layout,
                     IlvGraphic label)
```
    Transfers the layout parameter settings stored in this named property back to the input layout for the input label.
    
    Parameters:
    
    layout - The layout instance whose parameters are to be recovered from this named property.
    
    label - The label whose layout parameters are to be recovered from this named property.
  - dispose
```
public void dispose(IlvDefaultLabelingModel model)
```
    Disposes of the property and releases any resources that it is using. This is called if the property was loaded and removed from the manager.
    
    Parameters:
    
    model - The labeling model.
    
    See Also:
    
    IlvDefaultLabelingModel.loadParametersFromNamedProperties(IlvLabelLayout), IlvDefaultLabelingModel.removeParametersFromNamedProperties()

Class IlvLabelLayoutLabelProperty

Constructor Summary

Method Summary

Methods inherited from class ilog.views.IlvNamedProperty

Methods inherited from class java.lang.Object

Constructor Detail

IlvLabelLayoutLabelProperty

IlvLabelLayoutLabelProperty

IlvLabelLayoutLabelProperty

Method Detail

getLayout

omitDefaults

copy

isPersistent

isWritten

write

transfer

dispose