Placeholder
public
class
Placeholder
extends View
java.lang.Object | ||
↳ | View | |
↳ | android.support.constraint.Placeholder |
Added in 1.1
A Placeholder
provides a virtual object which can position an existing object.
When the id of another view is set on a placeholder (using setContent()
),
the placeholder effectively becomes the content view. If the content view exist on the
screen it is treated as gone from its original location.
The content view is positioned using the layout of the parameters of the Placeholder
(the Placeholder
is simply constrained in the layout like any other view).
Summary
Public constructors | |
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Placeholder(Context context)
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Placeholder(Context context, AttributeSet attrs)
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Placeholder(Context context, AttributeSet attrs, int defStyleAttr)
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Placeholder(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)
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Public methods | |
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View
|
getContent()
Returns the content view |
int
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getEmptyVisibility()
Returns the behaviour of a placeholder when it contains no view. |
void
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setContentId(int id)
Sets the content view id |
void
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setEmptyVisibility(int visibility)
Sets the visibility of placeholder when not containing objects typically gone or invisible. |
Inherited methods | |
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Public constructors
Placeholder
public Placeholder (Context context)
Parameters | |
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context |
Context |
Placeholder
public Placeholder (Context context, AttributeSet attrs)
Parameters | |
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context |
Context |
attrs |
AttributeSet |
Placeholder
public Placeholder (Context context, AttributeSet attrs, int defStyleAttr)
Parameters | |
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context |
Context |
attrs |
AttributeSet |
defStyleAttr |
int |
Placeholder
public Placeholder (Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)
Parameters | |
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context |
Context |
attrs |
AttributeSet |
defStyleAttr |
int |
defStyleRes |
int |
Public methods
getContent
public View getContent ()
Returns the content view
Returns | |
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View |
null if no content is set, otherwise the content view
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getEmptyVisibility
public int getEmptyVisibility ()
Returns the behaviour of a placeholder when it contains no view.
Returns | |
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int |
Either View.VISIBLE, View.INVISIBLE, View.GONE. Default is INVISIBLE |
setContentId
public void setContentId (int id)
Sets the content view id
Parameters | |
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id |
int : the id of the content view we want to place in the Placeholder
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setEmptyVisibility
public void setEmptyVisibility (int visibility)
Sets the visibility of placeholder when not containing objects typically gone or invisible. This can be important as it affects behaviour of surrounding components.
Parameters | |
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visibility |
int : Either View.VISIBLE, View.INVISIBLE, View.GONE
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