CardView
open class CardView : FrameLayout
kotlin.Any | ||||
↳ | android.view.View | |||
↳ | android.view.ViewGroup | |||
↳ | android.widget.FrameLayout | |||
↳ | androidx.cardview.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. androidx.cardview.R.attr#cardBackgroundColor
androidx.cardview.R.attr#cardCornerRadius
androidx.cardview.R.attr#cardElevation
androidx.cardview.R.attr#cardMaxElevation
androidx.cardview.R.attr#cardUseCompatPadding
androidx.cardview.R.attr#cardPreventCornerOverlap
androidx.cardview.R.attr#contentPadding
androidx.cardview.R.attr#contentPaddingLeft
androidx.cardview.R.attr#contentPaddingTop
androidx.cardview.R.attr#contentPaddingRight
androidx.cardview.R.attr#contentPaddingBottom
Summary
Public constructors | |
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<init>(@NonNull context: Context, @Nullable attrs: AttributeSet?) |
|
<init>(@NonNull context: Context, @Nullable attrs: AttributeSet?, defStyleAttr: Int) |
Public methods | |
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open ColorStateList |
Returns the background color state list of the CardView. |
open Float |
Returns the backward compatible elevation of the CardView. |
open Int |
Returns the inner padding before the Card's bottom edge |
open Int |
Returns the inner padding after the Card's left edge |
open Int |
Returns the inner padding before the Card's right edge |
open Int |
Returns the inner padding after the Card's top edge |
open Float |
Returns the backward compatible maximum elevation of the CardView. |
open Boolean |
Returns whether CardView should add extra padding to content to avoid overlaps with rounded corners on pre-Lollipop platforms. |
open Float |
Returns the corner radius of the CardView. |
open Boolean |
Returns whether CardView will add inner padding on platforms Lollipop and after. |
open Unit |
setCardBackgroundColor(@ColorInt color: Int) Updates the background color of the CardView |
open Unit |
setCardBackgroundColor(@Nullable color: ColorStateList?) Updates the background ColorStateList of the CardView |
open Unit |
setCardElevation(elevation: Float) Updates the backward compatible elevation of the CardView. |
open Unit |
setContentPadding(@Px left: Int, @Px top: Int, @Px right: Int, @Px bottom: Int) Sets the padding between the Card's edges and the children of CardView. |
open Unit |
setMaxCardElevation(maxElevation: Float) Updates the backward compatible maximum elevation of the CardView. |
open Unit |
setMinimumHeight(minHeight: Int) |
open Unit |
setMinimumWidth(minWidth: Int) |
open Unit |
setPadding(left: Int, top: Int, right: Int, bottom: Int) |
open Unit |
setPaddingRelative(start: Int, top: Int, end: Int, bottom: Int) |
open Unit |
setPreventCornerOverlap(preventCornerOverlap: Boolean) On pre-Lollipop platforms, CardView does not clip the bounds of the Card for the rounded corners. |
open Unit |