new AlertDialog.Builder(context)
    .setTitle("title")
    .setMessage("message")
    .setPositiveButton(android.R.string.ok, null)
    .show();

你可以使用下面的代码:

AlertDialog.Builder alertDialog2 = new AlertDialog.Builder(
    AlertDialogActivity.this);

// Setting Dialog Title
alertDialog2.setTitle("Confirm Delete...");

// Setting Dialog Message
alertDialog2.setMessage("Are you sure you want delete this file?");

// Setting Icon to Dialog
alertDialog2.setIcon(R.drawable.delete);

// Setting Positive "Yes" Btn
alertDialog2.setPositiveButton("YES",
    new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // Write your code here to execute after dialog
            Toast.makeText(getApplicationContext(),
                           "You clicked on YES", Toast.LENGTH_SHORT)
                    .show();
        }
    });

// Setting Negative "NO" Btn
alertDialog2.setNegativeButton("NO",
    new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // Write your code here to execute after dialog
            Toast.makeText(getApplicationContext(),
                           "You clicked on NO", Toast.LENGTH_SHORT)
                    .show();
            dialog.cancel();
        }
    });

// Showing Alert Dialog
alertDialog2.show();

对我来说

new AlertDialog.Builder(this)
    .setTitle("Closing application")
    .setMessage("Are you sure you want to exit?")
    .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {

          }
     }).setNegativeButton("No", null).show();

使用AlertDialog。建造者:

AlertDialog alertDialog = new AlertDialog.Builder(this)
//set icon 
 .setIcon(android.R.drawable.ic_dialog_alert)
//set title
.setTitle("Are you sure to Exit")
//set message
.setMessage("Exiting will call finish() method")
//set positive button
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialogInterface, int i) {
   //set what would happen when positive button is clicked    
        finish();
    }
})
//set negative button
.setNegativeButton("No", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialogInterface, int i) {
   //set what should happen when negative button is clicked
        Toast.makeText(getApplicationContext(),"Nothing Happened",Toast.LENGTH_LONG).show();
    }
})
.show();

您将得到以下输出。

要查看警报对话框教程使用下面的链接。

Android警报对话框教程

这是一个创建Alert对话框的基本示例:

AlertDialog.Builder dialog = new AlertDialog.Builder(MainActivity.this);
dialog.setCancelable(false);
dialog.setTitle("Dialog on Android");
dialog.setMessage("Are you sure you want to delete this entry?" );
dialog.setPositiveButton("Delete", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int id) {
        //Action for "Delete".
    }
})
        .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
            //Action for "Cancel".
            }
        });

final AlertDialog alert = dialog.create();
alert.show();

我想补充David Hedlund的回答，分享一个比他发布的更有活力的方法，这样当你有消极行为要做的时候，你可以使用它，当你没有的时候，我希望它能有所帮助。

private void showAlertDialog(@NonNull Context context, @NonNull String alertDialogTitle, @NonNull String alertDialogMessage, @NonNull String positiveButtonText, @Nullable String negativeButtonText, @NonNull final int positiveAction, @Nullable final Integer negativeAction, @NonNull boolean hasNegativeAction)
{
    AlertDialog.Builder builder;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        builder = new AlertDialog.Builder(context, android.R.style.Theme_Material_Dialog_Alert);
    } else {
        builder = new AlertDialog.Builder(context);
    }
    builder.setTitle(alertDialogTitle)
            .setMessage(alertDialogMessage)
            .setPositiveButton(positiveButtonText, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    switch (positiveAction)
                    {
                        case 1:
                            //TODO:Do your positive action here 
                            break;
                    }
                }
            });
            if(hasNegativeAction || negativeAction!=null || negativeButtonText!=null)
            {
            builder.setNegativeButton(negativeButtonText, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    switch (negativeAction)
                    {
                        case 1:
                            //TODO:Do your negative action here
                            break;
                        //TODO: add cases when needed
                    }
                }
            });
            }
            builder.setIcon(android.R.drawable.ic_dialog_alert);
            builder.show();
}