仿照DatePickerFragment实现的TimePickerFragment

public class TimePickerFragment extends DialogFragment {
    public static  final String EXTRA_HOUR="com.example.purplefragment.extra_hour";
    public static final String EXTRA_MINUTE="com.example.purplefragment.extra_minute";

    private static final String CURRENT_TIME_HOUR="com.example.purplefragment.current_time_hour";
    private static final String CURRENT_TIME_MINUTE="com.example.purplefragment.current_time_minute";


    private TimePicker mTimePicker;

    public static TimePickerFragment newInstance(int hour,int minute)
    {
        Bundle bundle=new Bundle();
        bundle.putInt(CURRENT_TIME_HOUR,hour);
        bundle.putInt(CURRENT_TIME_MINUTE,minute);
        TimePickerFragment dialog=new TimePickerFragment();
        dialog.setArguments(bundle);
        return dialog;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        int hour=getArguments().getInt(CURRENT_TIME_HOUR);
        int minute=getArguments().getInt(CURRENT_TIME_MINUTE);

        View v= LayoutInflater.from(getActivity())
                .inflate(R.layout.dialog_time,null);

        mTimePicker=(TimePicker)v.findViewById(R.id.time_picker);
        mTimePicker.setCurrentHour(hour);
        mTimePicker.setCurrentMinute(minute);

        return new AlertDialog.Builder(getActivity())
                .setView(v)
                .setTitle(R.string.time_picker_title)
                .setPositiveButton(android.R.string.ok,
                        new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                int hour=mTimePicker.getCurrentHour();
                                int minute=mTimePicker.getCurrentMinute();
                                sendResult(Activity.RESULT_OK,hour,minute);
                            }
                        })
                .create();
    }

    private void sendResult(int resultCode,int hour,int minute)
    {
        if(getTargetFragment()==null)
            return;
        Intent intent=new Intent();
        intent.putExtra(EXTRA_HOUR,hour);
        intent.putExtra(EXTRA_MINUTE,minute);
        getTargetFragment().onActivityResult(getTargetRequestCode(),resultCode,intent);
    }
}

<TimePicker xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/time_picker">

TimePicker>

mTimeButton=(Button)v.findViewById(R.id.crime_time);
        Calendar calendar=Calendar.getInstance();
        calendar.setTime(mCrime.getDate());
        //一开始没有加final时
        //使用newInstance方法传参数时会提示
        // hour be accessed from within inner class,shoule be declare final
        final int hour=calendar.get(Calendar.HOUR_OF_DAY);
        final int minute=calendar.get(Calendar.MINUTE);
        mTimeButton.setText(hour+":"+minute);
        mTimeButton.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v)
            {
                mIsChange=true;
                FragmentManager fragmentManager=getFragmentManager();
                TimePickerFragment dialog=TimePickerFragment.newInstance(hour,minute);
                dialog.setTargetFragment(CrimeFragment.this,REQUEST_TIME);
                dialog.show(fragmentManager,DIALOG_TIME);
                setIsChangeResult();
            }
        });

//为什么之前个体extra默认值设为0的时候，我只点了修改日期的按钮
        //时间会被重置为0呢，讲道理没有执行这个方法啊
        if(requestCode==REQUEST_TIME){
            int hour=intent.getIntExtra(TimePickerFragment.EXTRA_HOUR,mCrime.getDate().getHours());
            int minute=intent.getIntExtra(TimePickerFragment.EXTRA_MINUTE,mCrime.getDate().getMinutes());
            mTimeButton.setText(hour+":"+minute);
            mCrime.getDate().setHours(hour);
            mCrime.getDate().setMinutes(minute);

            updateDate();
        }