java - 如何在同一个 onTimeSet() 中提取两个时间选择器对话框的小时和分钟？

Question

我已经在 fragment 中实现了按钮按下时的时间选择器(工作)但是我如何提取两个对话框的小时和分钟以仅使用一个 onTimeSet() 来分隔变量, 它位于 MainActivity?

这是我的 MainActivity 中的 onTimeSet():

    public void onTimeSet(TimePicker timePicker, int i, int i1) {
        TextView textView = (TextView)findViewById(R.id.textstart);
        textView.setText("Hour: "+ i + " Minutes: "+ i1);

        getSupportFragmentManager().getFragments();

    }

这是我的工作 fragment :

Button timeButton = (Button) view.findViewById(R.id.timeButton);
        timeButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment timePicker = new TimePicker_Fragment();
                timePicker.show(getFragmentManager(), "Time Picker");
            }
        });

        Button timeButton2 = (Button) view.findViewById(R.id.timeButton2);
        timeButton2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment timePicker2 = new TimePicker_Fragment();
                timePicker2.show(getFragmentManager(), "Time Picker 2");
            }
        });

        return view;
    }

Answer 1

一种选择是更改应用程序的架构:

由于 TimePickerFragment 是唯一可以理解 onTimeSet() 中的 TimePicker 参数的，因此它是合乎逻辑的选择实现 TimePickerDialog.OnTimeSetListener。

TimePicker_Fragment 的两个实例可以通过一些自定义接口(interface)向托管 WorkFragment(最终是 Activity)报告。使用一些唯一值(String 或枚举)在您的 onTimeSet() 自定义版本中识别它们。

例如，您的 Activity 可以实现如下方法:

@Override
void onCustomTimeSet(String timePickerId, int hour, int minutes){
    switch(timePickerId){
        case "TIME_PICKER":
            // code for time  picker 1 here
            break;
        case "TIME_PICKER_2":
            // code for time  picker 1 here
            break;
    }
    // ...
}

...这将由 TimePicker_Fragment 中的“正常”onTimeSet(TimePicker, int, int) 的实现调用

@Override
void onTimeSet(TimePicker timePicker, int i, int i2){
    ((CustomTimePickerListener)getActivity()).onCustomTimeSet("TIME_PICKER_1", i, i2)
}

---

另一种选择是利用 TimePicker 是一个 View 这一事实，View 可以有一个 标签(可以是任何类型的 Object，请参阅 View.setTag())。

所以您可以让 TimePicker_Fragment 为 TimePicker 设置一个标签。

由于 TimePicker 是 TimePickerDialog 的一部分，设置 tag 的最简单方法似乎是(再次)TimePicker_Fragment 实现TimePickerDialog.OnTimeSetListener。但这一次，Activity 可以实现相同的接口(interface):

TimePicker_Fragment中的代码

void onTimeSet(TimePicker timePicker, int i, int i2){
    timePicker.setTag("TIME_PICKER");
    ((TimePickerDialog.OnTimeSetListener)getActivity()).onTimeSet(timePicker, i, i2);
}

Activity中的代码

void onTimeSet(TimePicker timePicker, int i, int i2){
    String tag = (String)timePicker.getTag();
    switch(tag){
        case "TIME_PICKER":
            // code for time  picker 1 here
            break;
        case "TIME_PICKER_2":
            // code for time  picker 2 here
            break;
    }
    // ...
}

---

为三个相关组件实现第二种解决方案的代码:

主 Activity .java

public class MainActivity extends AppCompatActivity implements TimePickerDialog.OnTimeSetListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getSupportFragmentManager().beginTransaction().add(R.id.fragment_container, new Work()).commit();
    }

    public void onTimeSet(TimePicker timePicker, int i, int i1){
        String tag = (String)timePicker.getTag();
        switch(tag){
            case TIME_PICKER:
                TextView textView = (TextView)findViewById(R.id.textstart);
                textView.setText("Start Hour: "+ i + " Minutes: "+ i1);
                break;
            case TIME_PICKER_2:
                TextView textView2 = (TextView)findViewById(R.id.textend);
                textView2.setText("Start Hour: "+ i + " Minutes: "+ i1);
                break;
        }
    }
}

工作.java

public class Work extends Fragment {

    public static final String TIME_PICKER = "TIME_PICKER";
    public static final String TIME_PICKER_2 = "TIME_PICKER_2";

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.frag_work, container, false);
        getActivity().setTitle("Work");

        Button timeButton = (Button) view.findViewById(R.id.btn1);
        timeButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment timePicker = TimePicker_Fragment.instance(TIME_PICKER);
                timePicker.show(getFragmentManager(), "Time Picker");
            }
        });

        Button timeButton2 = (Button) view.findViewById(R.id.btn2);
        timeButton2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment timePicker2 =TimePicker_Fragment.instance(TIME_PICKER_2);
                timePicker2.show(getFragmentManager(), "Time Picker 2");
            }
        });

        return view;
    }
}

TimePicker_Fragment.java

public class TimePicker_Fragment extends DialogFragment implements TimePickerDialog.OnTimeSetListener {

    private static final String KEY_TIMEPICKER_TAG = "KEY_TIMEPICKER_TAG";

    /**
     *
     * @param timePickerTag the tag by which you can identify a TimePicker.  
     *             Will be set as tag to the TimePicker View in onTimeSet()
     * @return x
     */
    public static TimePicker_Fragment instance(String timePickerTag){
        TimePicker_Fragment fragment = new TimePicker_Fragment();
        Bundle b = new Bundle();
        b.putString(KEY_TIMEPICKER_TAG, timePickerTag);
        fragment.setArguments(b);
        return fragment;
    }

    @NonNull
    @Override
    public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) {
        Calendar c = Calendar.getInstance();
        int hour = c.get(Calendar.HOUR_OF_DAY);
        int minute = c.get(Calendar.MINUTE);
        Context ctx = getContext();
        return new TimePickerDialog(ctx, this, hour, minute, DateFormat.is24HourFormat(ctx));
    }

    public void onTimeSet(TimePicker timePicker, int i, int i2){
        Bundle b = getArguments();
        assert b != null;
        timePicker.setTag(b.getString(KEY_TIMEPICKER_TAG));
        ((TimePickerDialog.OnTimeSetListener)getActivity()).onTimeSet(timePicker, i, i2);
    }
}