你可以下面的代码设置布局的宽度和高度从java。

final AlertDialog alertDialog  = alertDialogBuilder.create();
final WindowManager.LayoutParams WMLP = alertDialog.getWindow().getAttributes();

WMLP.gravity = Gravity.TOP;
WMLP.y = mActionBarHeight;
WMLP.x = getResources().getDimensionPixelSize(R.dimen.unknown_image_width);

alertDialog.getWindow().setAttributes(WMLP);
alertDialog.show();

在我的例子中，DialogFragment占用了完整的活动大小，就像一个Fragment一样。DialogFragment基于xml布局，而不是AlertDialog。我的错误在于将对话片段作为常规片段添加到FragmentManager中:

fragmentManager?.beginTransaction()?.run {
    replace(R.id.container, MyDialogFragment.newInstance(), MyDialogFragment.TAG)
    addToBackStack(MyDialogFragment.TAG)
}?.commitAllowingStateLoss()

相反，我需要显示对话片段:

val dialogFragment = MyDialogFragment.newInstance()
fragmentManager?.let { dialogFragment.show(it, MyDialogFragment.TAG) }

经过一些编辑(我在布局中有ViewPager2)，对话框片段变得太窄:

我使用了N1hk的解决方案:

override fun onActivityCreated(savedInstanceState: Bundle?) {
    super.onActivityCreated(savedInstanceState)

    dialog?.window?.attributes?.width = ViewGroup.LayoutParams.MATCH_PARENT
    dialog?.window?.attributes?.height = ViewGroup.LayoutParams.MATCH_PARENT
}

现在它已经定义了宽度和高度，而不是完整的活动大小。

我想说onCreateView和onCreateDialog。如果你有一个基于布局的对话片段，你可以使用这两种方法中的任何一种。

If you use onCreateView, then you should use onActivityCreated to set width. If you use onCreateDialog instead of onCreateView, you can set parameters there. onActivityCreated won't be needed. override fun onCreateDialog(savedInstanceState: Bundle?): Dialog { super.onCreateDialog(savedInstanceState) val view = activity?.layoutInflater?.inflate(R.layout.your_layout, null) val dialogBuilder = MaterialAlertDialogBuilder(context!!).apply { // Or AlertDialog.Builder(context!!).apply setView(view) // setCancelable(false) } view.text_view.text = "Some text" val dialog = dialogBuilder.create() // You can access dialog.window here, if needed. return dialog }

我使用AlertDialog创建对话框。所以我在OnShowListener中使用了Rodrigo的答案。

dialog.setOnShowListener(new OnShowListener() {

            @Override
            public void onShow(DialogInterface dialogInterface) {
                Display display = getWindowManager().getDefaultDisplay();
                DisplayMetrics outMetrics = new DisplayMetrics ();
                display.getMetrics(outMetrics);
                dialog.getWindow().setLayout((int)(312 * outMetrics.density), (int)(436 * outMetrics.density));
            }

        });

要获得一个几乎覆盖整个屏幕的Dialog:首先定义一个ScreenParameter类

public class ScreenParameters
{
    public static int Width;
    public static  int Height;

    public ScreenParameters()
    {
        LayoutParams l = new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.MATCH_PARENT);
        Width= l.width;
        Height = l.height;
    }
}

然后你必须在getDialog.getWindow().setLayout()方法之前调用screenparameter

@Override
public void onResume()
{
    super.onResume();
    ScreenParameters s = new ScreenParameters();
    getDialog().getWindow().setLayout(s.Width , s.Height);
}

我把@rmirabella的回答也更新了一下，让它也能处理身高问题:

private fun DialogFragment.setSize(widthPercentage: Int, heightPercentage: Int) {
    val newWidth = widthPercentage.toFloat() / 100
    val newHeight = heightPercentage.toFloat() / 100
    val dm = Resources.getSystem().displayMetrics
    val rect = dm.run { Rect(0, 0, widthPixels, heightPixels) }
    val percentWidth = rect.width() * newWidth
    val percentHeight = rect.height() * newHeight
    dialog?.window?.setLayout(percentWidth.toInt(), percentHeight.toInt())
}

然后在你的DialogFragment中或onStart()之后:

override fun onStart() {
    super.onStart()
    setSize(
        widthPercentage = 100,
        heightPercentage = 80
    )
}

这里是kotlin版本

    override fun onResume() {
        super.onResume()

        val params:ViewGroup.LayoutParams = dialog.window.attributes
        params.width = LinearLayout.LayoutParams.MATCH_PARENT
        params.height = LinearLayout.LayoutParams.MATCH_PARENT
        dialog.window.attributes = params as android.view.WindowManager.LayoutParams
    }