这是在kotlin中完成的

val builder: AlertDialog.Builder = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            AlertDialog.Builder(this, android.R.style.Theme_Material_Dialog_Alert)
        } else {
            AlertDialog.Builder(this)
        }
        builder.setTitle("Delete Alert!")
                .setMessage("Are you want to delete this entry?")
                .setPositiveButton("YES") { dialog, which ->

                }
                .setNegativeButton("NO") { dialog, which ->

                }
                .setIcon(R.drawable.ic_launcher_foreground)
                .show()

只是简单的一个!在你的Java类中创建一个dialog方法，就像这样:

public void openDialog() {
    final Dialog dialog = new Dialog(context); // Context, this, etc.
    dialog.setContentView(R.layout.dialog_demo);
    dialog.setTitle(R.string.dialog_title);
    dialog.show();
}

现在创建布局XML dialog_demo.xml并创建UI/设计。下面是我为演示目的创建的一个示例:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/dialog_info"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="@string/dialog_text"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:layout_below="@id/dialog_info">

        <Button
            android:id="@+id/dialog_cancel"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="0.50"
            android:background="@color/dialog_cancel_bgcolor"
            android:text="Cancel"/>

        <Button
            android:id="@+id/dialog_ok"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="0.50"
            android:background="@color/dialog_ok_bgcolor"
            android:text="Agree"/>
    </LinearLayout>
</RelativeLayout>

现在你可以从任何你喜欢的地方调用openDialog():)下面是上面代码的截图。

注意，文本和颜色来自strings.xml和colors.xml。你可以定义你自己的。

public void showSimpleDialog(View view) {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setCancelable(false);
    builder.setTitle("AlertDialog Title");
    builder.setMessage("Simple Dialog Message");
    builder.setPositiveButton("OK!!!", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int id) {
            //
        }
    })
    .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {

        }
    });

    // Create the AlertDialog object and return it
    builder.create().show();
}

也可以看看我的关于Android对话的博客，你会在这里找到所有的细节:http://www.fahmapps.com/2016/09/26/dialogs-in-android-part1/。

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();
}

您可以使用AlertDialog创建对话框。构建器

试试这个:

AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("Are you sure you want to delete this entry?");

        builder.setPositiveButton("Yes, please", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                //perform any action
                Toast.makeText(getApplicationContext(), "Yes clicked", Toast.LENGTH_SHORT).show();
            }
        });

        builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                //perform any action
                Toast.makeText(getApplicationContext(), "No clicked", Toast.LENGTH_SHORT).show();
            }
        });

        //creating alert dialog
        AlertDialog alertDialog = builder.create();
        alertDialog.show();

要改变Alert对话框的正反按钮的颜色，你可以在alertDialog.show()后面写下面两行;

alertDialog.getButton(AlertDialog.BUTTON_POSITIVE).setTextColor(getResources().getColor(R.color.colorPrimary));
alertDialog.getButton(AlertDialog.BUTTON_NEGATIVE).setTextColor(getResources().getColor(R.color.colorPrimaryDark));

   new AlertDialog.Builder(v.getContext()).setMessage("msg to display!").show();