小编Jon*_* Ch的帖子

最近我按照了如何创建警告对话框的教程,当我点击删除按钮时,它应该在删除之前向我显示警告,但它会崩溃.有人能告诉我我的错误在哪里吗？

以下是我的代码:

// Delete button click event
    btnDeleteEvent.setOnClickListener(new View.OnClickListener() {

        public void onClick(View arg0) {
            // alerting user before deleting event
            AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
                    getApplicationContext());
            // set title
            alertDialogBuilder.setTitle("Warning!");
            // set dialog message
            alertDialogBuilder
                    .setMessage("Are you sure to delete event?")
                    .setCancelable(false)
                    .setPositiveButton("Yes",
                            new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog,
                                        int id) {
                                    // if yes, deleting event in background
                                    // thread
                                    new DeleteEvent().execute();
                                }
                            })
                    .setNegativeButton("No",
                            new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog,
                                        int id) {
                                    // if …