public class ComentarDialog extends DialogFragment{
private EditText comentario;

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {

    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

    LayoutInflater inflater = LayoutInflater.from(getActivity());
    View v = inflater.inflate(R.layout.dialog_comentar, null);
    comentario = (EditText)v.findViewById(R.id.etxt_comentar_dialog);

    builder.setTitle("Comentar")
           .setView(v)
           .setPositiveButton("OK", null)
           .setNegativeButton("CANCELAR", new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog, int id) {

               }
           });

    return builder.create();
}

@Override
public void onStart() {
    super.onStart();

    //Obtenemos el AlertDialog
    AlertDialog dialog = (AlertDialog)getDialog();

    dialog.setCanceledOnTouchOutside(false);
    dialog.setCancelable(false);//Al presionar atras no desaparece

    //Implementamos el listener del boton OK para mostrar el toast
    dialog.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if(TextUtils.isEmpty(comentario.getText())){
               Toast.makeText(getActivity(), "Ingrese un comentario", Toast.LENGTH_SHORT).show();
               return;
            }
            else{
                ((AlertDialog)getDialog()).dismiss();
            }
        }
    });

    //Personalizamos
    Resources res = getResources();

    //Buttons
    Button positive_button = dialog.getButton(DialogInterface.BUTTON_POSITIVE);
    positive_button.setBackground(res.getDrawable(R.drawable.btn_selector_dialog));

    Button negative_button =  dialog.getButton(DialogInterface.BUTTON_NEGATIVE);
    negative_button.setBackground(res.getDrawable(R.drawable.btn_selector_dialog));

    int color = Color.parseColor("#304f5a");

    //Title
    int titleId = res.getIdentifier("alertTitle", "id", "android");
    View title = dialog.findViewById(titleId);
    if (title != null) {
        ((TextView) title).setTextColor(color);
    }

    //Title divider
    int titleDividerId = res.getIdentifier("titleDivider", "id", "android");
    View titleDivider = dialog.findViewById(titleDividerId);
    if (titleDivider != null) {
        titleDivider.setBackgroundColor(res.getColor(R.color.list_menu_divider));
    }
}
}

这段代码对你有用，因为我有一个类似的问题，这对我有用。：）

1-重写片段对话框类中的Onstart（）方法。

@Override
public void onStart() {
    super.onStart();
    final AlertDialog D = (AlertDialog) getDialog();
    if (D != null) {
        Button positive = (Button) D.getButton(Dialog.BUTTON_POSITIVE);
        positive.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                if (edittext.equals("")) {
   Toast.makeText(getActivity(), "EditText empty",Toast.LENGTH_SHORT).show();
                } else {
                D.dismiss(); //dissmiss dialog
                }
            }
        });
    }
}

为DialogFragment使用自定义布局，并在内容下添加LinearLayout，该布局可以设置为无边框，以匹配Google Material Design。然后找到新创建的按钮并覆盖其OnClickListener。

例子：

public class AddTopicFragment extends DialogFragment {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
        // Get the layout inflater
        LayoutInflater inflater = getActivity().getLayoutInflater();
        final View dialogView = inflater.inflate(R.layout.dialog_add_topic, null);

        Button saveTopicDialogButton = (Button) dialogView.findViewById(R.id.saveTopicDialogButton);
        Button cancelSaveTopicDialogButton = (Button) dialogView.findViewById(R.id.cancelSaveTopicDialogButton);

        final AppCompatEditText addTopicNameET = (AppCompatEditText) dialogView.findViewById(R.id.addTopicNameET);
        final AppCompatEditText addTopicCreatedByET = (AppCompatEditText) dialogView.findViewById(R.id.addTopicCreatedByET);

        saveTopicDialogButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // validate inputs
                if(addTopicNameET.getText().toString().trim().isEmpty()){
                    addTopicNameET.setError("Topic name can't be empty");
                    addTopicNameET.requestFocus();
                }else if(addTopicCreatedByET.getText().toString().trim().isEmpty()){
                    addTopicCreatedByET.setError("Topic created by can't be empty");
                    addTopicCreatedByET.requestFocus();
                }else {
                    // save topic to database
                    Topic topic = new Topic();
                    topic.name = addTopicNameET.getText().toString().trim();
                    topic.createdBy = addTopicCreatedByET.getText().toString().trim();
                    topic.createdDate = new Date().getTime();
                    topic.save();
                    AddTopicFragment.this.dismiss();
                }
            }
        });

        cancelSaveTopicDialogButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AddTopicFragment.this.dismiss();
            }
        });

        // Inflate and set the layout for the dialog
        // Pass null as the parent view because its going in the dialog layout
        builder.setView(dialogView)
               .setMessage(getString(R.string.add_topic_message));

        return builder.create();
    }

}

dialog_add_topic.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:padding="@dimen/activity_horizontal_margin"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.design.widget.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:errorEnabled="true">

        <android.support.v7.widget.AppCompatEditText
            android:id="@+id/addTopicNameET"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Topic Name"
            android:inputType="textPersonName"
            android:maxLines="1" />

    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:errorEnabled="true">

        <android.support.v7.widget.AppCompatEditText
            android:id="@+id/addTopicCreatedByET"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Created By"
            android:inputType="textPersonName"
            android:maxLines="1" />

    </android.support.design.widget.TextInputLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <Button
            android:text="@string/cancel"
            android:layout_weight="1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/cancelSaveTopicDialogButton"
            style="@style/Widget.AppCompat.Button.ButtonBar.AlertDialog" />

        <Button
            android:text="@string/save"
            android:layout_weight="1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/saveTopicDialogButton"
            style="@style/Widget.AppCompat.Button.ButtonBar.AlertDialog" />

    </LinearLayout>


</LinearLayout>

这是最终结果。

科特林

val dialogView = LayoutInflater.from(requireContext()).inflate(R.layout.dialog_userinput, null)
        val dialogBuilder = MaterialAlertDialogBuilder(requireContext(), R.style.AlertDialogTheme)
   
        dialogBuilder.setView(dialogView)
        dialogBuilder.setCancelable(false)
        dialogBuilder.setPositiveButton("send",null)
        dialogBuilder.setNegativeButton("cancel") { dialog,_ ->
        dialog.dismiss()
        }


        val alertDialog = dialogBuilder.create()
        alertDialog.show()

        val positiveButton = alertDialog.getButton(AlertDialog.BUTTON_POSITIVE)
        positiveButton.setOnClickListener {
            val myInputText = dialogView.etxt_userinput.text.toString().trim()
            if(myInputText.isNotEmpty()){
             //Do something
            }else{
                //Prompt error
                dialogView.etxt_userinput.error = "Please fill this"
            }
        }

我们只需使用dialogBuilder创建一个AlertDialog，然后根据需要设置肯定按钮

超简单的Kotlin方法

 with(AlertDialog.Builder(this)) {
        setTitle("Title")
        setView(R.layout.dialog_name)
        setPositiveButton("Ok", null)
        setNegativeButton("Cancel") { _, _ -> }
        create().apply {
            setOnShowListener {
                getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener {
                    //Validate and dismiss
                    dismiss()
                }
            }
        }
    }.show()

如果您正在使用DialogFragment，这是处理Dialog的推荐方法。

AlertDialog的setButton（）方法（我认为AlertDialogBuilder的setPositiveButton（（）和setNegativeButton（）也是如此）所发生的事情是，您使用它设置的按钮（例如AlertDialog.button_POSITIVE）在按下时实际上会触发两个不同的OnClickListener对象。

第一个是DialogInterface.OnClickListener，它是setButton（）、setPositiveButton（（）和setNegativeButton（）的参数。

另一个是View.OnClickListener，它将被设置为在按下任何按钮时自动关闭AlertDialog，并且由AlertDialog自身设置。

您可以做的是使用带有null的setButton（）作为DialogInterface.OnClickListener来创建按钮，然后在View.OnClick Listener中调用自定义操作方法。例如，

@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
    AlertDialog alertDialog = new AlertDialog(getActivity());
    // set more items...
    alertDialog.setButton(AlertDialog.BUTTON_POSITIVE, "OK", null);

    return alertDialog;
}

然后，您可以在DialogFragment的onResume（）方法中重写默认AlertDialog的按钮View.OnClickListener（否则将关闭对话框）：

@Override
public void onResume()
{
    super.onResume();
    AlertDialog alertDialog = (AlertDialog) getDialog();
    Button okButton = alertDialog.getButton(AlertDialog.BUTTON_POSITIVE);
    okButton.setOnClickListener(new View.OnClickListener() { 
        @Override
        public void onClick(View v)
        {
            performOkButtonAction();
        }
    });
}

private void performOkButtonAction() {
    // Do your stuff here
}

您需要在onResume（）方法中设置此值，因为getButton（）将返回null，直到显示对话框！

这将导致您的自定义操作方法只被调用一次，默认情况下对话框不会被关闭。