问题
I want to corner only the top of a cardview.
I used below property and it is rounding all the corner.
I want to show an overlap of all cards
card_view:cardCornerRadius="4dp"
here is my layout
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
card_view:cardCornerRadius="4dp"
card_view:cardPreventCornerOverlap="false"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="@+id/re1">
<TextView
android:id="@+id/title"
android:layout_width="match_parent"
android:layout_height="20dp"
android:background="@color/colorAccent"
android:text="contact det"
android:gravity="center_vertical"
android:textColor="@android:color/white"
android:textSize="14dp"/>
<TextView
android:id="@+id/txtName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name"
android:gravity="center_vertical"
android:textSize="10dp"
android:layout_below="@id/title"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"/>
<TextView
android:id="@+id/txtSurname"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Surname"
android:gravity="center_vertical"
android:textSize="10dp"
android:layout_below="@id/txtName"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"
/>
<TextView
android:id="@+id/txtEmail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Email"
android:textSize="10dp"
android:layout_marginTop="10dp"
android:layout_alignParentRight="true"
android:layout_marginRight="150dp"
android:layout_alignBaseline="@id/txtName"/>
<TextView
android:id="@+id/txtAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Address"
android:textSize="10dp"
android:layout_alignLeft="@id/txtEmail"
android:layout_alignBaseline="@id/txtSurname"/>
</RelativeLayout>
</android.support.v7.widget.CardView>
回答1:
We can set the marginBottom of the card view in negative value.Margin should be same value as card radius. For Example,
<FrameLayout
android:id="@+id/rootview"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.CardView
android:id="@+id/card_view"
android:layout_marginBottom="-3dp"
project:cardCornerRadius="3dp"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!--The child view inside the cardview should have extra padding,so that negative margin will not affect the bottom padding of its child.Here normally we have 16dp bottom padding for child + margin bottom of the parent is 3dp=19dp comes.-->
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="19dp"/>
</android.support.v7.widget.CardView>
</FrameLayout>
It works for me.But I am in doubt whether it is the proper way of doing.Any suggestions are welcome.
回答2:
I have been trying the same but none of the solutions provided worked for me.
The only thing that worked was:
1) Make a custom background resource (like a rectangle shape) with rounded corners.
2) set this custom background using the command -
cardView = view.findViewById(R.id.card_view2);
cardView.setBackgroundResource(R.drawable.card_view_bg);
Worked perfectly for me! Hope this helps you.
The XML layout I made with top left and bottom right radius.
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="@color/white" />
<corners android:topLeftRadius="18dp" android:bottomRightRadius="18dp" />
</shape>
In your case, you need to change only topLeftRadius as well as topRightRadius.
回答3:
Tricky thing because you can't make CardView do this. Internally it uses a RoundRectDrawable (package private) which uses roundRect like this:
// rectf, rx, ry, paint
canvas.drawRoundRect(mBoundsF, mRadius, mRadius, paint);
Therefore you need a different solution, for example I found this gist by Ahmed-Abdelmeged where they use canvas clipping per each corner using a path to describe the outline.
So while I'm not the one who made this code, I'll post it here for future travellers.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="RoundedView">
<attr name="topLeftCornerRadius" format="dimension" />
<attr name="topRightCornerRadius" format="dimension" />
<attr name="bottomLeftCornerRadius" format="dimension" />
<attr name="bottomRightCornerRadius" format="dimension" />
</declare-styleable>
</resources>
and
package com.abdelmeged.ahmed.roundedlayout;
/**
* Created by ahmed on 9/17/2017.
*/
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Path;
import android.graphics.RectF;
import android.graphics.Region;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.View;
import android.widget.FrameLayout;
/**
* Custom wrapper view to get round corner round view
*/
public class RoundedView extends FrameLayout {
/**
* The corners than can be changed
*/
private float topLeftCornerRadius;
private float topRightCornerRadius;
private float bottomLeftCornerRadius;
private float bottomRightCornerRadius;
public RoundedView(@NonNull Context context) {
super(context);
init(context, null, 0);
}
public RoundedView(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
init(context, attrs, 0);
}
public RoundedView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context, attrs, defStyleAttr);
}
private void init(Context context, AttributeSet attrs, int defStyle) {
TypedArray typedArray = context.obtainStyledAttributes(attrs,
R.styleable.RoundedView, 0, 0);
//get the default value form the attrs
topLeftCornerRadius = typedArray.getDimension(R.styleable.
RoundedView_topLeftCornerRadius, 0);
topRightCornerRadius = typedArray.getDimension(R.styleable.
RoundedView_topRightCornerRadius, 0);
bottomLeftCornerRadius = typedArray.getDimension(R.styleable.
RoundedView_bottomLeftCornerRadius, 0);
bottomRightCornerRadius = typedArray.getDimension(R.styleable.
RoundedView_bottomRightCornerRadius, 0);
typedArray.recycle();
setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
@Override
protected void dispatchDraw(Canvas canvas) {
int count = canvas.save();
final Path path = new Path();
float[] cornerDimensions = {
topLeftCornerRadius, topLeftCornerRadius,
topRightCornerRadius, topRightCornerRadius,
bottomRightCornerRadius, bottomRightCornerRadius,
bottomLeftCornerRadius, bottomLeftCornerRadius};
path.addRoundRect(new RectF(0, 0, canvas.getWidth(), canvas.getHeight())
, cornerDimensions, Path.Direction.CW);
canvas.clipPath(path);
super.dispatchDraw(canvas);
canvas.restoreToCount(count);
}
public void setTopLeftCornerRadius(float topLeftCornerRadius) {
this.topLeftCornerRadius = topLeftCornerRadius;
invalidate();
}
public void setTopRightCornerRadius(float topRightCornerRadius) {
this.topRightCornerRadius = topRightCornerRadius;
invalidate();
}
public void setBottomLeftCornerRadius(float bottomLeftCornerRadius) {
this.bottomLeftCornerRadius = bottomLeftCornerRadius;
invalidate();
}
public void setBottomRightCornerRadius(float bottomRightCornerRadius) {
this.bottomRightCornerRadius = bottomRightCornerRadius;
invalidate();
}
}
This will let you clip the edge of images and views before they get rendered, therefore it does exactly what you want.
回答4:
As per the question, I am assuming that you want to apply corner radius property to only top of the card. You can obtain this effect by using two CardView. Place one CardView inside another CardView and remove outer CardView corner radius property. Also apply a transparent background to your outer CardView Your inner CardView will have a cornerRadius value of 4dp. Then apply a marginTop to your inner CardView, so that its bottom part becomes hidden by the outer CardView. This way, the bottom corner radius of your inner CardView will be hidden.
You will have to put your xml content in your Inner CardView. Outer CardView serves only the purpose of hiding the bottom rounded corners of the inner CardView.
Your xml layout will look like this:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view_outer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
card_view:cardBackgroundColor="@android:color/transparent"
card_view:cardCornerRadius="0dp"
card_view:cardElevation="4dp" >
<android.support.v7.widget.CardView
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="3dp"
card_view:cardElevation="0dp"
card_view:cardCornerRadius="4dp"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="@+id/re1">
<TextView
android:id="@+id/title"
android:layout_width="match_parent"
android:layout_height="20dp"
android:background="@color/colorAccent"
android:text="contact det"
android:gravity="center_vertical"
android:textColor="@android:color/white"
android:textSize="14dp"/>
<TextView
android:id="@+id/txtName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name"
android:gravity="center_vertical"
android:textSize="10dp"
android:layout_below="@id/title"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"/>
<TextView
android:id="@+id/txtSurname"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Surname"
android:gravity="center_vertical"
android:textSize="10dp"
android:layout_below="@id/txtName"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"
/>
<TextView
android:id="@+id/txtEmail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Email"
android:textSize="10dp"
android:layout_marginTop="10dp"
android:layout_alignParentRight="true"
android:layout_marginRight="150dp"
android:layout_alignBaseline="@id/txtName"/>
<TextView
android:id="@+id/txtAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Address"
android:textSize="10dp"
android:layout_alignLeft="@id/txtEmail"
android:layout_alignBaseline="@id/txtSurname"/>
</RelativeLayout>
</android.support.v7.widget.CardView>
</android.support.v7.widget.CardView>
I have taken reference from this SO question: Question. I hope it solves your problem.
来源：https://stackoverflow.com/questions/34454182/round-only-top-corner-of-cardview