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()

可以添加builder.show（）；在返回之前的验证消息之后；

这样地

    public void login()
{
    final AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setView(R.layout.login_layout);
    builder.setTitle("Login");



    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int id)
        {
            dialog.cancel();
        }
    });// put the negative button before the positive button, so it will appear

    builder.setPositiveButton("Ok", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int id)
        {
            Dialog d = (Dialog) dialog;
            final EditText etUserName = (EditText) d.findViewById(R.id.etLoginName);
            final EditText etPassword = (EditText) d.findViewById(R.id.etLoginPassword);
            String userName = etUserName.getText().toString().trim();
            String password = etPassword.getText().toString().trim();

            if (userName.isEmpty() || password.isEmpty())
            {

                Toast.makeText(getApplicationContext(),
                        "Please Fill all fields", Toast.LENGTH_SHORT).show();
                builder.show();// here after validation message before retrun
                               //  it will reopen the dialog
                              // till the user enter the right condition
                return;
            }

            user = Manager.get(getApplicationContext()).getUserByName(userName);

            if (user == null)
            {
                Toast.makeText(getApplicationContext(),
                        "Error ethier username or password are wrong", Toast.LENGTH_SHORT).show();
                builder.show();
                return;
            }
            if (password.equals(user.getPassword()))
            {
                etPassword.setText("");
                etUserName.setText("");
                setLogged(1);
                setLoggedId(user.getUserId());
                Toast.makeText(getApplicationContext(),
                        "Successfully logged in", Toast.LENGTH_SHORT).show();
               dialog.dismiss();// if every thing is ok then dismiss the dialog
            }
            else
            {
                Toast.makeText(getApplicationContext(),
                        "Error ethier username or password are wrong", Toast.LENGTH_SHORT).show();
                builder.show();
                return;
            }

        }
    });

    builder.show();

}

以下是针对所有类型对话框的一些解决方案，包括AlertDialog.Builder的解决方案，该解决方案可以在所有API级别上工作（低于API 8，而这里的另一个答案则不适用）。有使用AlertDialog.Builder、DialogFragment和DialogPreference的AlertDialog解决方案。

下面的代码示例显示了如何覆盖默认的公共按钮处理程序，并防止这些不同形式的对话框关闭对话框。所有示例都显示了如何防止肯定按钮关闭对话框。

注意：对于那些需要更多详细信息的人来说，下面的示例描述了基本android类的对话框关闭是如何在后台工作的，以及为什么选择以下方法

AlertDialog.Builder-显示后立即更改默认按钮处理程序（）

AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setMessage("Test for preventing dialog close");
builder.setPositiveButton("Test", 
        new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which)
            {
                //Do nothing here because we override this button later to change the close behaviour. 
                //However, we still need this because on older versions of Android unless we 
                //pass a handler the button doesn't get instantiated
            }
        });
final AlertDialog dialog = builder.create();
dialog.show();
//Overriding the handler immediately after show is probably a better approach than OnShowListener as described below
dialog.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener()
      {            
          @Override
          public void onClick(View v)
          {
              Boolean wantToCloseDialog = false;
              //Do stuff, possibly set wantToCloseDialog to true then...
              if(wantToCloseDialog)
                  dialog.dismiss();
              //else dialog stays open. Make sure you have an obvious way to close the dialog especially if you set cancellable to false.
          }
      });
      

DialogFragment-重写onResume（）

@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    builder.setMessage("Test for preventing dialog close");
    builder.setPositiveButton("Test", 
        new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which)
            {
                //Do nothing here because we override this button later to change the close behaviour. 
                //However, we still need this because on older versions of Android unless we 
                //pass a handler the button doesn't get instantiated
            }
        });
    return builder.create();
}

//onStart() is where dialog.show() is actually called on 
//the underlying dialog, so we have to do it there or 
//later in the lifecycle.
//Doing it in onResume() makes sure that even if there is a config change 
//environment that skips onStart then the dialog will still be functioning
//properly after a rotation.
@Override
public void onResume()
{
    super.onResume();    
    final AlertDialog d = (AlertDialog)getDialog();
    if(d != null)
    {
        Button positiveButton = (Button) d.getButton(Dialog.BUTTON_POSITIVE);
        positiveButton.setOnClickListener(new View.OnClickListener()
                {
                    @Override
                    public void onClick(View v)
                    {
                        Boolean wantToCloseDialog = false;
                        //Do stuff, possibly set wantToCloseDialog to true then...
                        if(wantToCloseDialog)
                            d.dismiss();
                        //else dialog stays open. Make sure you have an obvious way to close the dialog especially if you set cancellable to false.
                    }
                });
    }
}

DialogPreference-覆盖showDialog（）

@Override
protected void onPrepareDialogBuilder(Builder builder)
{
    super.onPrepareDialogBuilder(builder);
    builder.setPositiveButton("Test", this);   //Set the button here so it gets created
}

@Override
protected void showDialog(Bundle state)
{       
    super.showDialog(state);    //Call show on default first so we can override the handlers

    final AlertDialog d = (AlertDialog) getDialog();
    d.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener()
            {            
                @Override
                public void onClick(View v)
                {
                    Boolean wantToCloseDialog = false;
                    //Do stuff, possibly set wantToCloseDialog to true then...
                    if(wantToCloseDialog)
                        d.dismiss();
                    //else dialog stays open. Make sure you have an obvious way to close the dialog especially if you set cancellable to false.
                }
            });
}

方法说明：

通过查看Android源代码，AlertDialog默认实现通过向OnCreate（）中的所有实际按钮注册公共按钮处理程序来工作。单击按钮时，通用按钮处理程序会将单击事件转发给您在setButton（）中传递的任何处理程序，然后调用该处理程序会关闭对话框。如果希望在按下其中一个按钮时阻止对话框关闭，则必须替换按钮实际视图的通用按钮处理程序。因为它是在OnCreate（）中分配的，所以必须在调用默认的OnCreate（（）实现后替换它。在show（）方法的过程中调用OnCreate。您可以创建一个自定义对话框类，并重写OnCreate（）以调用super.OnCreate（），然后重写按钮处理程序，但是如果您创建了自定义对话框，则无法免费获得Builder，在这种情况下，有什么意义？因此，按照对话框的设计方式使用对话框，但同时控制何时关闭对话框，一种方法是首先调用dialog.Show（），然后使用dialog.getButton（）获取对按钮的引用，以覆盖单击处理程序。另一种方法是使用setOnShowListener（）并实现查找按钮视图并替换OnShowListen中的处理程序。两者之间的功能差异“几乎”为零，这取决于最初创建对话框实例的线程。通过查看源代码，onShowListener被发送到创建该对话框的线程上运行的处理程序的消息调用。所以，由于OnShowListener是由发布在消息队列上的消息调用的，所以从技术上讲，调用侦听器可能会在显示完成后延迟一段时间。因此，我认为最安全的方法是首先调用show.Dialog（），然后立即在同一执行路径中替换按钮处理程序。由于调用show（）的代码将在主GUI线程上运行，这意味着在该线程上执行任何其他代码之前，都将先执行您跟随show（）执行的代码，而OnShowListener方法的计时取决于消息队列。

这个链接的答案是一个简单的解决方案，它与API 3兼容。它与Tom Bollwitt的解决方案非常相似，但没有使用兼容性较差的OnShowListener。

是的，你可以。您基本上需要：使用DialogBuilder创建对话框show（）对话框在显示的对话框中查找按钮并覆盖其onClickListener

自从我扩展EditTextPreference以来，我对Kamen的代码进行了一些小的修改。

@Override
protected void showDialog(Bundle state) {
  super.showDialog(state);

  class mocl implements OnClickListener{
    private final AlertDialog dialog;
    public mocl(AlertDialog dialog) {
          this.dialog = dialog;
      }
    @Override
    public void onClick(View v) {

        //checks if EditText is empty, and if so tells the user via Toast
        //otherwise it closes dialog and calls the EditTextPreference's onClick
        //method to let it know that the button has been pressed

        if (!IntPreference.this.getEditText().getText().toString().equals("")){
        dialog.dismiss();
        IntPreference.this.onClick(dialog,DialogInterface.BUTTON_POSITIVE);
        }
        else {
            Toast t = Toast.makeText(getContext(), "Enter a number!", Toast.LENGTH_SHORT);
            t.show();
        }

    }
  }

  AlertDialog d = (AlertDialog) getDialog();
  Button b = d.getButton(DialogInterface.BUTTON_POSITIVE);
  b.setOnClickListener(new mocl((d)));
}

真有趣！

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

这可能是一个很晚的回复，但使用setCancelable就可以了。

alertDial.setCancelable(false);