尝试设置待办事项的完成清单。我试图在单击按钮时使对话框显示，但该对话框没有出现。

showdone.setOnClicklistener(new View.OnClicklistener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder = new AlertDialog.Builder(todo.this);
                builder.setadapter(itemdone,new DialogInterface.OnClicklistener() {
                    @Override
                    public void onClick(DialogInterface dialog,int which) {
                        String strDone = itemdone.getItem(which);
                        AlertDialog.Builder builderInner = new AlertDialog.Builder(todo.this);
                        builderInner.setTitle("Done List");
                        builderInner.setMessage(strDone);
                        builderInner.setPositiveButton("Ok",new DialogInterface.OnClicklistener() {
                            @Override
                            public void onClick(DialogInterface dialog,int which) {
                                dialog.dismiss();
                            }
                        });
                        builderInner.create().show();
                    }
                });
                builder.show();
            }
        });