belongs to Maven artifact com.android.support:cardview-v7:28.0.0-alpha1
CardView
public
class
CardView
extends FrameLayout
java.lang.Object | ||||
↳ | android.view.View | |||
↳ | android.view.ViewGroup | |||
↳ | android.widget.FrameLayout | |||
↳ | android.support.v7.widget.CardView |
A FrameLayout with a rounded corner background and shadow.
CardView uses elevation
property on Lollipop for shadows and falls back to a
custom emulated shadow implementation on older platforms.
Due to expensive nature of rounded corner clipping, on platforms before Lollipop, CardView does
not clip its children that intersect with rounded corners. Instead, it adds padding to avoid such
intersection (See setPreventCornerOverlap(boolean)
to change this behavior).
Before Lollipop, CardView adds padding to its content and draws shadows to that area. This
padding amount is equal to maxCardElevation + (1 - cos45) * cornerRadius
on the
sides and maxCardElevation * 1.5 + (1 - cos45) * cornerRadius
on top and bottom.
Since padding is used to offset content for shadows, you cannot set padding on CardView.
Instead, you can use content padding attributes in XML or
setContentPadding(int, int, int, int)
in code to set the padding between the edges of
the CardView and children of CardView.
Note that, if you specify exact dimensions for the CardView, because of the shadows, its content
area will be different between platforms before Lollipop and after Lollipop. By using api version
specific resource values, you can avoid these changes. Alternatively, If you want CardView to add
inner padding on platforms Lollipop and after as well, you can call
setUseCompatPadding(boolean)
and pass true
.
To change CardView's elevation in a backward compatible way, use
setCardElevation(float)
. CardView will use elevation API on Lollipop and before
Lollipop, it will change the shadow size. To avoid moving the View while shadow size is changing,
shadow size is clamped by getMaxCardElevation()
. If you want to change elevation
dynamically, you should call setMaxCardElevation(float)
when CardView is initialized.
Summary
XML attributes | |
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CardView_cardBackgroundColor |
|
CardView_cardCornerRadius |
|
CardView_cardElevation |
|
CardView_cardMaxElevation |
|
CardView_cardPreventCornerOverlap |
|
CardView_cardUseCompatPadding |
|
CardView_contentPadding |
|
CardView_contentPaddingBottom |
|
CardView_contentPaddingLeft |
|
CardView_contentPaddingRight |
|
CardView_contentPaddingTop |
Inherited constants |
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android.view.ViewGroup
|
![]()
android.view.View
|
Inherited fields |
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![]()
android.view.View
|
Public constructors | |
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CardView(Context context)
|
|
CardView(Context context, AttributeSet attrs)
|
|
CardView(Context context, AttributeSet attrs, int defStyleAttr)
|
Public methods | |
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ColorStateList
|
getCardBackgroundColor()
Returns the background color state list of the CardView. |
float
|
getCardElevation()
Returns the backward compatible elevation of the CardView. |
int
|
getContentPaddingBottom()
Returns the inner padding before the Card's bottom edge |
int
|
getContentPaddingLeft()
Returns the inner padding after the Card's left edge |
int
|
getContentPaddingRight()
Returns the inner padding before the Card's right edge |
int
|
getContentPaddingTop()
Returns the inner padding after the Card's top edge |
float
|
getMaxCardElevation()
Returns the backward compatible maximum elevation of the CardView. |
boolean
|
getPreventCornerOverlap()
Returns whether CardView should add extra padding to content to avoid overlaps with rounded corners on pre-Lollipop platforms. |
float
|
getRadius()
Returns the corner radius of the CardView. |
boolean
|
getUseCompatPadding()
Returns whether CardView will add inner padding on platforms Lollipop and after. |
void
|
setCardBackgroundColor(int color)
Updates the background color of the CardView |
void
|
setCardBackgroundColor(ColorStateList color)
Updates the background ColorStateList of the CardView |
void
|
setCardElevation(float elevation)
Updates the backward compatible elevation of the CardView. |
void
|
setContentPadding(int left, int top, int right, int bottom)
Sets the padding between the Card's edges and the children of CardView. |
void
|
setMaxCardElevation(float maxElevation)
Updates the backward compatible maximum elevation of the CardView. |
void
|
setMinimumHeight(int minHeight)
|
void
|
setMinimumWidth(int minWidth)
|
void
|
setPadding(int left, int top, int right, int bottom)
|
void
|
setPaddingRelative(int start, int top, int end, int bottom)
|
void
|
setPreventCornerOverlap(boolean preventCornerOverlap)
On pre-Lollipop platforms, CardView does not clip the bounds of the Card for the rounded corners. |
void
|
setRadius(float radius)
Updates the corner radius of the CardView. |
void
|
setUseCompatPadding(boolean useCompatPadding)
CardView adds additional padding to draw shadows on platforms before Lollipop. |
Protected methods | |
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void
|
onMeasure(int widthMeasureSpec, int heightMeasureSpec)
|
Inherited methods | |
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android.widget.FrameLayout
|