请参阅以下代码：

Dialog dialog = new Dialog(MainActivity.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.dialog);
TextView textView = (TextView) dialog.findViewById(R.id.textView);
textView.setText("Custom Text Example");
dialog.show();
 
WindowManager.LayoutParams layoutParams = dialog.getWindow().getAttributes();
layoutParams.dimAmount = .7f;
dialog.getWindow().setAttributes(layoutParams);

自定义对话框的布局xml文件如下：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/progressDialogCustom"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/dialog_black"
    android:orientation="horizontal"
    android:padding="10dp" >
 
    <ProgressBar
        android:id="@+id/progressBar1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
 
    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:gravity="center_vertical"
        android:textColor="@android:color/white"
        android:text="Updating Profile . . ." />
 
</LinearLayout>

@ drawable / dialog_black文件如下：

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle" >
 
    <solid android:color="@android:color/background_dark" />
 
    <corners
        android:bottomLeftRadius="7dp"
        android:bottomRightRadius="7dp"
        android:topLeftRadius="7dp"
        android:topRightRadius="7dp" />
 
    <stroke
        android:width="1px"
        android:color="@android:color/darker_gray" />
 
    <padding
        android:bottom="5dp"
        android:left="5dp"
        android:right="5dp"
        android:top="5dp" />
 
</shape>