Android 无法在首选项的自定义对话框中使用时间选择器

由于我想自定义自己的timepicker对话框，所以我不使用提供的timepickerdialog。然而，我发现如果我优先调用对话框，它是不起作用的。但如果我把它放在一个普通的xml布局中，这是可行的。eclipse没有检查代码中的错误，但如果我在phone中运行，则从下面的粗体行开始显示nullpointerexception

public class Prefs extends PreferenceActivity{

    Preference time;

    void openCustomDialog() {
        AlertDialog.Builder customDialog = new AlertDialog.Builder(Prefs.this);
        customDialog.setTitle("Set Delay Time");
        LayoutInflater layoutInflater = (LayoutInflater) getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View view = layoutInflater.inflate(R.layout.timepicker, null); 
        TimePicker minute = (TimePicker) findViewById(R.id.mPicker);
        **minute.setOnTimeChangedListener(new TimePicker.OnTimeChangedListener()** {
            public void onTimeChanged(TimePicker view, int hourOfDay, int minute) {
            }
        });
        minute.setCurrentMinute(usb.minute);

        TimePicker second = (TimePicker) findViewById(R.id.sPicker);
        second.setOnTimeChangedListener(new TimePicker.OnTimeChangedListener() {
            public void onTimeChanged(TimePicker view, int hourOfDay, int second) {
            }
        });
        second.setCurrentMinute(usb.second);
        customDialog.setPositiveButton("OK",new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface arg0, int arg1) {
                    }
                });
        customDialog.setView(view);
        customDialog.show();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.prefs);

        time = (Preference)findPreference("time");

        time.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
            @Override
            public boolean onPreferenceClick(Preference arg0) { 
                openCustomDialog();  
                return true;
            }
        });
}

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这主要是猜测，但我认为错误的前一行应该是

view.findViewById（R.id.mPicker）

。我检查了几次，但仍然没有发现错误