Question

所以我有一个按钮，我想将settext设置为在Dialog Fragment中选择的日期。我尝试过使用SharedPreferences，但除非重新启动片段，否则它不会更新。我试着看一下片段的生命周期，但我不认为它对Dialog Fragment的工作原理是一样的。所以我的问题是如何从片段

启动的对话框片段中设置片段的文本

这是我的Dialog Fragment代码

public class DatePickerDialogTheme extends DialogFragment implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        final Calendar calendar = Calendar.getInstance();
        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH);
        int day = calendar.get(Calendar.DAY_OF_MONTH);

        return new DatePickerDialog(getActivity(), R.style.DatePickerTheme,this,year,month,day);
    }

    @Override
    public void onDateSet(DatePicker datePicker, int i, int i1, int i2) {

        String string = (i1 + 1) + "/" +i2 + "/" + i;
        SharedPreferences.Editor editor = getActivity().getSharedPreferences("itemInfo", Context.MODE_PRIVATE).edit();
        editor.putString("Birthday", string);
        editor.apply();


    }
}

这就是我正在尝试更改片段

中的文本

mButton = view.findViewById(R.id.openCalendar);
mButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment dialogFragment = new DatePickerDialogTheme();
                dialogFragment.show(getActivity().getFragmentManager(), "Theme");
            }
        });

我也尝试在onResume期间更改文本，但仍然无法正常工作。当DialogFragment打开时，我认为它不会调用onResume。

Answer 1

这是一种正确的方法：

定义接收结果的接口（请注意，我使用getChildFragmentManager访问子片段的管理器，不要使用call getFragmentManager

public interface DatePickerResultHandler {
    void onDatePicked(DatePickerDialogTheme dialog, int year, int month, int day);
}

让外部Fragment实现接口以接收结果

public class TestFragment extends Fragment implements DatePickerResultHandler {
    private Button mButton;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_test, container, false);
        mButton = view.findViewById(R.id.test_btn);
        mButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment dialogFragment = new DatePickerDialogTheme();
                dialogFragment.show(getChildFragmentManager(), "Theme");
            }
        });

        return view;
    }

    @Override
    public void onDatePicked(DatePickerDialogTheme dialog, int year, int month, int day) {
        String string = (year + 1) + "/" + month + "/" + day;
        mButton.setText(string);
    }
}

在DatePickerResultHandler 中找到DatePickerDialogTheme。如果您仅将此对话框附加到Activity，请先尝试使用Context或Activity进行投射。如果将其附加到父片段，请将其强制转换为getParentFragment

public class DatePickerDialogTheme extends DialogFragment implements DatePickerDialog.OnDateSetListener {
    private boolean isAttach;
    private DatePickerResultHandler mResultHandler;

    @Override
    public void onAttach(Context context) {
        if (!isAttach) {
            findResultHandler(context);
            findResultHandler(getParentFragment());

            isAttach = true;
        }

        super.onAttach(context);
    }

    @Override
    public void onAttach(Activity activity) {
        if (!isAttach) {
            findResultHandler(activity);
            findResultHandler(getParentFragment());

            isAttach = true;
        }

        super.onAttach(activity);
    }

    private void findResultHandler(Object parent) {
        if (mResultHandler == null && parent instanceof DatePickerResultHandler)
            mResultHandler = (DatePickerResultHandler) parent;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        final Calendar calendar = Calendar.getInstance();
        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH);
        int day = calendar.get(Calendar.DAY_OF_MONTH);

        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    @Override
    public void onDateSet(DatePicker datePicker, int year, int month, int day) {
        if (mResultHandler != null)
            mResultHandler.onDatePicked(this, year, month, day);

        dismiss();
    }
}

Answer 2

将您的TextView对象传递到正在初始化它的片段广告的构造函数中，然后设置所需的文本。这可能是您尝试做的快速方法。

public class DatePickerDialogTheme extends DialogFragment implements DatePickerDialog.OnDateSetListener {
private TextView tv;

DatePickerDialogTheme(TextView tv){
    this.tv = tv;
}

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {

    final Calendar calendar = Calendar.getInstance();
    int year = calendar.get(Calendar.YEAR);
    int month = calendar.get(Calendar.MONTH);
    int day = calendar.get(Calendar.DAY_OF_MONTH);

    return new DatePickerDialog(getActivity(), R.style.DatePickerTheme,this,year,month,day);
}

@Override
public void onDateSet(DatePicker datePicker, int i, int i1, int i2) {

    String string = (i1 + 1) + "/" +i2 + "/" + i;
    tv.setText(string);
   }

}

而另一部分 -

tv= parentViewOfTextView.findViewById(R.id.textView);
mButton = view.findViewById(R.id.openCalendar);
mButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            DialogFragment dialogFragment = new DatePickerDialogTheme(tv);
            dialogFragment.show(getActivity().getFragmentManager(), "Theme");
        }
    });

Answer 3

感谢其他答案，但这对我来说效果最好。

我刚用过

Button button = getActivity().findViewById(R.id.calendarView);
button.setText(string);

在我的对话框片段中，它可以正常工作。

如何从对话框片段中设置片段中的文本？

3 个答案: