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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
<init>(@NonNull context: Context)

<init>(@NonNull context: Context, @Nullable attrs: AttributeSet?)

<init>(@NonNull context: Context, @Nullable attrs: AttributeSet?, defStyleAttr: Int)

Public methods
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

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: