Android自定义样式圆角dialog对话框

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginHorizontal="16dp">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="18sp"
        android:textColor="@color/black"
        android:textStyle="bold"
        android:layout_marginTop="14dp"
        android:gravity="center"
        android:layout_gravity="center"
        android:id="@+id/title"/>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="16sp"
        android:textColor="@color/black"
        android:layout_marginTop="16dp"
        android:layout_marginHorizontal="16dp"
        android:gravity="center"
        android:layout_gravity="center"
        android:id="@+id/message"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginHorizontal="20dp"
        android:layout_marginTop="16dp">
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="取消"
            android:textSize="16sp"
            android:textColor="@color/white"
            android:background="@null"
            android:layout_marginRight="14dp"
            android:id="@+id/btn_cancel"/>
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="确定"
            android:textSize="16sp"
            android:textColor="@color/white"
            android:id="@+id/btn_confirm"/>
    </LinearLayout>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="@color/white" />
    <corners android:radius="20dp"/>
</shape>

public void my_dialog(Context context)  {
        View inflateLayout = LayoutInflater.from(context).inflate(R.layout.my_dialog,null);
        TextView unbind_title = (TextView) inflateLayout.findViewById(R.id.title);
        unbind_title.setText("标题");
        TextView unbind_message = (TextView) inflateLayout.findViewById(R.id.message);
        unbind_message.setText("正文");
        AlertDialog builderDialog = new AlertDialog.Builder(context)
                .setView(inflateLayout)
                .setCancelable(false)  //使用户只能通过点击对话框的确定或取消关闭对话框
                .create();

        inflateLayout.findViewById(R.id.btn_confirm).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(context, "你点击了确定", Toast.LENGTH_SHORT).show();
                builderDialog.dismiss();
            }
        });

        inflateLayout.findViewById(R.id.btn_cancel).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(context, "你点击了取消", Toast.LENGTH_SHORT).show();
                builderDialog.dismiss();
            }
        });
        builderDialog.getWindow().setBackgroundDrawableResource(R.drawable.my_dialog_shape); //设置对话框的样式
        WindowManager.LayoutParams params = builderDialog.getWindow().getAttributes();
        params.y = 1000;
        builderDialog.getWindow().setAttributes(params);
        builderDialog.show();
        builderDialog.getWindow().setGravity(Gravity.TOP); //设置对话框展示在距离屏幕顶部1000的位置
    }

Button pops_up = (Button) findViewById(R.id.pops_up);
        pops_up.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                my_dialog(MainActivity.this);
            }
        });