在同一活动中实现两个TimePicker

Question

我在同一个活动中使用了两个时间选择器，让用户为特定任务选择开始时间和停止时间，我使用了支持库中可用的DialogFragment类，以向后兼容旧的Android版本。

package com.calls.only;

import java.util.Calendar;

import android.app.Dialog;
import android.app.TimePickerDialog;
import android.app.TimePickerDialog.OnTimeSetListener;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;

public class TimePickerFragment extends DialogFragment {

    @Override 
    public Dialog onCreateDialog(Bundle savedInstanceState) {
         // Use the current time as the default values for the picker
        final Calendar c = Calendar.getInstance();
        int hour = c.get(Calendar.HOUR_OF_DAY);
        int minute = c.get(Calendar.MINUTE);

        if (!(getActivity() instanceof OnTimeSetListener)) throw new IllegalStateException("Activity should implement OnTimeSetListener!");
            OnTimeSetListener timeSetListener =  (OnTimeSetListener) getActivity();

        // Create a new instance of TimePickerDialog and return it
        return new TimePickerDialog(getActivity(), timeSetListener, hour, minute, false);
    }
}

package com.calls.only;
import java.util.Calendar;
import java.util.TimeZone;
import android.os.Bundle;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.DialogFragment;
import android.view.Menu;
import android.view.View;
import android.widget.RadioButton;
import android.widget.TextView;

public class MainActivity extends FragmentActivity implements TimePickerDialog.OnTimeSetListener {

    public void InputStartTime(View v) {
        DialogFragment newFragment = new TimePickerFragment();
        newFragment.show(getSupportFragmentManager(), "timePicker");
    }

    public void InputEndTime(View v) {
        DialogFragment newFragment = new TimePickerFragment();
        newFragment.show(getSupportFragmentManager(), "timePicker");
    }

    public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
            Log.i("TimePicker", "Time picker set!");
    }

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}

Answer 1

不是在活动中实现TimePickerDialog.OnTimeSetListener，而是将其提供给构造函数中的片段。这样，每个实例都可以做不同的事情。

所以你可以像这样使用它：

  frag1 = new TimePickerFragment(new TimePickerDialog.OnTimeSetListener() { /* Your implementation*/ });