dialog小小感悟

来源：互联网发布：snmp获取端口号编辑：程序博客网时间：2024/06/04 19:22

前言

因为最近在做项目，然后遇上困难，虽然在老鸟眼中不是很难，但是我想提醒自己，所以注文把

正文

那天遇上这个错误

代码

datePicker.init(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH), new OnDateChangedListener(){@Overridepublic void onDateChanged(DatePicker view, int year, int monthOfYear, int dayOfMonth){calendar.set(year, monthOfYear, dayOfMonth);Toast.makeText(getApplicationContext(), "密码或者帐号错误,请检查后再输入!", Toast.LENGTH_SHORT).show();flushDate(year, monthOfYear, dayOfMonth, calendar.get(Calendar.HOUR_OF_DAY), calendar.get(Calendar.MINUTE));}});                 TimePicker timePicker=(TimePicker)findViewById(R.id.timePicker);                 timePicker.setOnTimeChangedListener(new OnTimeChangedListener(){public void onTimeChanged(TimePicker view, int hourOfDay, int minute){calendar.set(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH),calendar.get(Calendar.DAY_OF_MONTH), hourOfDay, minute);flushDate(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH), hourOfDay, minute);}});

错误截图

错误地方：DatePicker datePicker=(DatePicker)findViewById(R.id.datePicker);

错误修改：DatePicker datePicker = (DatePicker)textEntryView.findViewById(R.id.datePicker);

错误原因：

因为你要从父亲那里找R.id.datePicker 而它的父亲是R.layout.time也就是final View textEntryView = factory.inflate(R.layout.time, null);

如果你DatePicker datePicker=(DatePicker)findViewById(R.id.datePicker);
它会默认是DatePicker datePicker=(DatePicker)this.findViewById(R.id.datePicker);而this是DailyActivity的context，所以会在R.layout.daily里面找这个控件，而在R.layout.daily里并没有定义这个R.id.datePicker，所以会报空指针异常。