How to make custom dialog with rounded corners in android

Question

Create an XML file in drawable, say dialog_bg.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid
        android:color="@color/white"/>
    <corners
        android:radius="30dp" />
    <padding
        android:left="10dp"
        android:top="10dp"
        android:right="10dp"
        android:bottom="10dp" />
</shape>

set it as the background in your layout XML:

android:background="@drawable/dialog_bg"

Set the background of the dialog's root view to transparent, because Android puts your dialog layout within a root view that hides the corners in your custom layout.

Java:

dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

Kotlin:

dialog.window?.setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))

You need to do the following:

• Create a background with rounded corners for the Dialog's background:

  <?xml version="1.0" encoding="utf-8"?>
  <shape xmlns:android="http://schemas.android.com/apk/res/android"
  android:shape="rectangle" >
  
      <solid android:color="#fff" />
  
      <corners
          android:bottomLeftRadius="8dp"
          android:bottomRightRadius="8dp"
          android:topLeftRadius="8dp"
          android:topRightRadius="8dp" />
  
  </shape>
  

• Now in your Dialog's XML file in the root layout use that background with required margin:

  android:layout_marginLeft="20dip"
  android:layout_marginRight="20dip"
  android:background="@drawable/dialog_background"
  

• finally in the java part you need to do this:

  dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
  dialog.setContentView(layoutResId);
  View v = getWindow().getDecorView();
  v.setBackgroundResource(android.R.color.transparent);
  

This works perfectly for me.

dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

this works for me

With the Androidx library and Material Components Theme you can override the getTheme() method:

import androidx.fragment.app.DialogFragment

class RoundedDialog: DialogFragment() {

    override fun getTheme() = R.style.RoundedCornersDialog

    //....

}

with:

<style name="RoundedCornersDialog" parent="@style/Theme.MaterialComponents.Dialog">
    <item name="dialogCornerRadius">16dp</item>
</style>

Or you can use the MaterialAlertDialogBuilder included in the Material Components Library:

import androidx.fragment.app.DialogFragment
import com.google.android.material.dialog.MaterialAlertDialogBuilder

class RoundedAlertDialog : DialogFragment() {

    //...

    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        return MaterialAlertDialogBuilder(requireActivity(), R.style.MaterialAlertDialog_rounded)
                .setTitle("Test")
                .setMessage("Message")
                .setPositiveButton("OK", null)
                .create()
    }

}

with:

<style name="MaterialAlertDialog_rounded" parent="@style/ThemeOverlay.MaterialComponents.MaterialAlertDialog">
    <item name="shapeAppearanceOverlay">@style/DialogCorners</item>
</style>

<style name="DialogCorners">
    <item name="cornerFamily">rounded</item>
    <item name="cornerSize">16dp</item>
</style>

If you don't need a DialogFragment just use the MaterialAlertDialogBuilder.

dimen.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <integer name="weight">1</integer>

    <dimen name="dialog_top_radius">21dp</dimen>

    <dimen name="textview_dialog_head_min_height">50dp</dimen>
    <dimen name="textview_dialog_drawable_padding">5dp</dimen>

    <dimen name="button_dialog_layout_margin">3dp</dimen>


</resources>

styles.xml

<style name="TextView.Dialog">
        <item name="android:paddingLeft">@dimen/dimen_size</item>
        <item name="android:paddingRight">@dimen/dimen_size</item>
        <item name="android:gravity">center_vertical</item>
        <item name="android:textColor">@color/black</item>
    </style>

    <style name="TextView.Dialog.Head">
        <item name="android:minHeight">@dimen/textview_dialog_head_min_height</item>
        <item name="android:textColor">@color/white</item>
        <item name="android:background">@drawable/dialog_title_style</item>
        <item name="android:drawablePadding">@dimen/textview_dialog_drawable_padding</item>
    </style>

    <style name="TextView.Dialog.Text">
        <item name="android:textAppearance">@style/Font.Medium.16</item>
    </style>

    <style name="Button" parent="Base.Widget.AppCompat.Button">
        <item name="android:layout_height">@dimen/button_min_height</item>
        <item name="android:layout_width">match_parent</item>
        <item name="android:textColor">@color/white</item>
        <item name="android:gravity">center</item>
        <item name="android:textAppearance">@style/Font.Medium.20</item>
    </style>

 <style name="Button.Dialog">
        <item name="android:layout_weight">@integer/weight</item>
        <item name="android:layout_margin">@dimen/button_dialog_layout_margin</item>
    </style>

    <style name="Button.Dialog.Middle">
        <item name="android:background">@drawable/button_primary_selector</item>
    </style>

dialog_title_style.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <gradient
        android:angle="270"
        android:endColor="@color/primaryDark"
        android:startColor="@color/primaryDark" />

    <corners
        android:topLeftRadius="@dimen/dialog_top_radius"
        android:topRightRadius="@dimen/dialog_top_radius" />

</shape>

dialog_background.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="@color/backgroundDialog" />
    <corners
        android:topLeftRadius="@dimen/dialog_top_radius"
        android:topRightRadius="@dimen/dialog_top_radius" />
    <padding />
</shape>

dialog_one_button.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/dailog_background"
    android:orientation="vertical">

    <TextView
        android:id="@+id/dialogOneButtonTitle"
        style="@style/TextView.Dialog.Head"
        android:text="Process Completed" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginRight="16dp"
        android:orientation="vertical">

        <TextView
            android:id="@+id/dialogOneButtonText"
            style="@style/TextView.Dialog.Text"
            android:text="Return the main menu" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <Button
                android:id="@+id/dialogOneButtonOkButton"
                style="@style/Button.Dialog.Middle"
                android:text="Ok" />

        </LinearLayout>

    </LinearLayout>

</LinearLayout>

OneButtonDialog.java

package com.example.sametoztoprak.concept.dialogs;

import android.app.Dialog;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.TextView;

import com.example.sametoztoprak.concept.R;
import com.example.sametoztoprak.concept.models.DialogFields;

/**
 * Created by sametoztoprak on 26/09/2017.
 */

public class OneButtonDialog extends Dialog implements View.OnClickListener {

    private static OneButtonDialog oneButtonDialog;
    private static DialogFields dialogFields;

    private Button dialogOneButtonOkButton;
    private TextView dialogOneButtonText;
    private TextView dialogOneButtonTitle;

    public OneButtonDialog(AppCompatActivity activity) {
        super(activity);
    }

    public static OneButtonDialog getInstance(AppCompatActivity activity, DialogFields dialogFields) {
        OneButtonDialog.dialogFields = dialogFields;
        return oneButtonDialog = (oneButtonDialog == null) ? new OneButtonDialog(activity) : oneButtonDialog;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.dialog_one_button);
        getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

        dialogOneButtonTitle = (TextView) findViewById(R.id.dialogOneButtonTitle);
        dialogOneButtonText = (TextView) findViewById(R.id.dialogOneButtonText);
        dialogOneButtonOkButton = (Button) findViewById(R.id.dialogOneButtonOkButton);

        dialogOneButtonOkButton.setOnClickListener(this);
    }

    @Override
    protected void onStart() {
        super.onStart();
        dialogOneButtonTitle.setText(dialogFields.getTitle());
        dialogOneButtonText.setText(dialogFields.getText());
        dialogOneButtonOkButton.setText(dialogFields.getOneButton());
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.dialogOneButtonOkButton:

                break;
            default:
                break;
        }
        dismiss();
    }
}

If you use Material Components:

CustomDialog.kt

class CustomDialog: DialogFragment() {

    override fun getTheme() = R.style.RoundedCornersDialog

}

styles.xml

<style name="RoundedCornersDialog" parent="Theme.MaterialComponents.Dialog">
    <item name="dialogCornerRadius">dimen</item>
</style>

Setting

dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

will prevent dialog to cast a shadow.

Solution is to use

dialog.getWindow().setBackgroundDrawableResource(R.drawable.dialog_rounded_background);

where is R.drawable.dialog_rounded_background

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
    <item>
        <shape android:shape="rectangle" android:padding="10dp">
            <solid
                android:color="@color/dialog_bg_color"/>
            <corners
                android:radius="30dp" />
        </shape>
    </item>

</layer-list>