Android 屏幕旋转时如何改变DialogFragment的布局

Question

我有一个自定义 DialogFragment，其中包含两个 DatePicker 小部件（从和到，使用 layout/custom_date_picker）。

我需要在屏幕旋转到横向时更改 dialogFragment 的布局（使用 layout-land/custom_date_picker）。

Activity的配置是：

<activity
        android:name=".activities.MainActivity"
        android:configChanges="orientation|keyboardHidden|screenSize"
        android:launchMode="singleTop"/>

实现的DialogFragment来源是：

public class DatePickerDialog extends DialogFragment
{

public static final String START_SEARCH_DATE = "startSearchDate";
public static final String END_SEARCH_DATE = "endSearchDate";
private CustomDatePicker dpStartDate;
private CustomDatePicker dpEndDate;
private AlertDialog d;

public interface DatePickerDialogListener
{
    void onFinishDatePickDialog(String fromDate, String toDate);
}

public DatePickerDialog()
{
}

// Use this instance of the interface to deliver action events
DatePickerDialogListener mListener;

// Override the Fragment.onAttach() method to instantiate the DatePickerDialogListener
@Override
public void onAttach(Activity activity)
{
    super.onAttach(activity);
    // Verify that the host activity implements the callback interface
    try
    {
        // Instantiate the NoticeDialogListener so we can send events to the host
        mListener = (DatePickerDialogListener) activity;
    } catch (ClassCastException e)
    {
        // The activity doesn't implement the interface, throw exception
        throw new ClassCastException(activity.toString() + " must implement DatePickerDialogListener");
    }
}

public static DatePickerDialog newInstance(String startSearchDate, String endSearchDate)
{
    DatePickerDialog frag = new DatePickerDialog();
    Bundle args = new Bundle();
    args.putString(START_SEARCH_DATE, startSearchDate);
    args.putString(END_SEARCH_DATE, endSearchDate);
    frag.setArguments(args);
    return frag;
}

@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
    View customView = getActivity().getLayoutInflater().inflate(R.layout.custom_date_picker, null);
    // Define your date pickers
    dpStartDate = (CustomDatePicker) customView.findViewById(R.id.dpStartDate);
    dpEndDate = (CustomDatePicker) customView.findViewById(R.id.dpEndDate);

    String startSearchDate = getArguments().getString(START_SEARCH_DATE);
    String endSearchDate = getArguments().getString(END_SEARCH_DATE);

    dpStartDate.updateDate(startSearchDate);
    dpEndDate.updateDate(endSearchDate);

    d = new AlertDialog.Builder(getActivity())
            .setView(customView)
            .setTitle(getString(R.string.datepicker_hint))
            .setPositiveButton(getString(R.string.ok), new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {

                }
            }) //Set to null. We override the onclick
            .setNegativeButton(getString(R.string.cancel), null)
            .create();
    d.show();
    d.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {

            boolean b = DateUtils.largerThanEndDate(dpStartDate, dpEndDate);
            if (b)
            {
                ToastUtils.showShortText(getActivity(), getString(R.string.date_error));
            } else
            {
                mListener.onFinishDatePickDialog(dpStartDate.getDate(), dpEndDate.getDate());
                dismiss();
            }
        }
    });
    return d;
}
}

谁能指导我如何做到这一点？提前致谢。

编辑： 这是我调用 DialogFragment:

的代码

public void showDatePicker()
{
    startSearchDate = dateModel.getStartDate();
    endSearchDate = dateModel.getEndDate();
    datePickerDialog = (DatePickerDialog)fragmentManager.findFragmentByTag(DATE_PICKER_DIALOG);

    if (alertDialog == null)
    {
        alertDialog = DatePickerDialog.newInstance(startSearchDate, endSearchDate);
        alertDialog.show(fragmentManager, DATE_PICKER_DIALOG);
    }

}

Answer 1

我想您可以考虑在 onCreate() 中使用 if 子句，如下所示：

int rotation = getWindowManager().getDefaultDisplay().getRotation();

然后

switch(rotation){
    case Surface.ROTATION_0: 
    case Surface.ROTATION_180:
        // show portrait

    case Surface.ROTATION_90: 
    case Surface.ROTATION_270:
        // show landscape
}

对于纵向模式，堆叠显示两个对话框。对于横向模式，并排显示它们。

编辑：

逐点回答：

旋转phone时，必然会重新创建Activity。这意味着 onCreate() 将在轮换时调用 。因此，旋转 state 可以在 onCreate() 中确定，如上所示。在这种情况下，使 rotation 成为 class 成员字段，以便可以在整个 class.
确实，正如您正确指出的那样，对话框可以从 onConfigurationChanged() 或 onCreate() 本身显示。为此，以及如何保存实例状态，请参阅附件链接。

参考文献：

1. How to properly retain a DialogFragment through rotation?.

2. Why won't Fragment retain state when screen is rotated?.

Android 屏幕旋转时如何改变DialogFragment的布局

How to change the layout of DialogFragment when the screen is rotated in Android

android

android-layout

screen-rotation

android-fragments

android-dialogfragment