到目前为止我能想到的最简单的方法

如果你的对话框是由垂直线性布局组成的，只需添加一个“高度填充”虚拟视图，它将占据屏幕的整个高度。

例如:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          android:orientation="vertical"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:weightSum="1">

    <EditText
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:id="@+id/editSearch" />

    <ListView
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:id="@+id/listView"/>


   <!-- this is a dummy view that will make sure the dialog is highest -->
   <View
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:layout_weight="1"/>

</LinearLayout>

注意LinearLayout属性中的android:weightSum="1"和dummy View属性中的android:layout_weight="1"

dialog.getWindow().setLayout(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);

下面是我的自定义对话框宽度的变体:

DisplayMetrics displaymetrics = new DisplayMetrics();
mActivity.getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
int width = (int) (displaymetrics.widthPixels * (ThemeHelper.isPortrait(mContext) ? 0.95 : 0.65));

WindowManager.LayoutParams params = getWindow().getAttributes();
params.width = width;
getWindow().setAttributes(params);

因此，根据设备方向(ThemeHelper.isPortrait(mContext))对话框的宽度将是95%(纵向模式)或65%(横向模式)。这比作者要求的要多一点，但对某些人来说可能有用。

你需要创建一个从Dialog扩展而来的类，并把这段代码放到你的onCreate(Bundle savedInstanceState)方法中。

对于对话框的高度，代码应该类似于此。

public static WindowManager.LayoutParams setDialogLayoutParams(Activity activity, Dialog dialog)
    {
        try 
        {
            Display display = activity.getWindowManager().getDefaultDisplay();
            Point screenSize = new Point();
            display.getSize(screenSize);
            int width = screenSize.x;

            WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();
            layoutParams.copyFrom(dialog.getWindow().getAttributes());
            layoutParams.width = (int) (width - (width * 0.07) ); 
            layoutParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
            return layoutParams;
        } 
        catch (Exception e)
        {
            e.printStackTrace();
            return null;
        }
    }

dialog.getWindow().setLayout(WindowManager.LayoutParams.MATCH_PARENT,WindowManager.LayoutParams.WRAP_CONTENT);

***In Kotlin You can Code like This : -*** 

fun customDialog(activity: Activity?, layout: Int): Dialog {
    val dialog = Dialog(activity!!)
    try {
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE)
        dialog.setCancelable(false)
        dialog.setContentView(layout)
        dialog.window!!.setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
        dialog.window!!.setLayout(ConstraintLayout.LayoutParams.MATCH_PARENT, ConstraintLayout.LayoutParams.WRAP_CONTENT);
        dialog.show()
    } catch (e: Exception) {

    }
    return dialog
}