从对话框片段返回字符串返回到活动 [英] Returning String from Dialog Fragment back to Activity

问题描述

我已经阅读了很多帖子，但我找不到适用于这种情况的任何内容。

我有一个时间选择器对话框，我把整数值一起在一个字符串中，我需要将此字符串返回到主要活动。

然后，此字符串值将用于设置按钮的文本。 p>

如果有人可以帮助我，这将是非常感谢。

谢谢

对话框片段

  public class TimePickerFragment extends DialogFragment implements TimePickerDialog.OnTimeSetListener {
 @Override 
 public Dialog onCreateDialog（Bundle savedInstanceState）{
 //使用当前时间作为选择器的默认值
 final Calendar c = Calendar.getInstance（）; 
 int hour = c.get（Calendar.HOUR_OF_DAY）; 
 int minute = c.get（Calendar.MINUTE）; 
 
 //创建一个新的TimePickerDialog实例并返回它
返回新的TimePickerDialog（getActivity（），this，hour，minute，DateFormat.is24HourFormat（getActivity（）））; 
} 
 
 public void onTimeSet（TimePicker视图，int hourOfDay，int minute）{
 //按照用户选择的时间执行某些操作
 String Time = Integer .toString（hourOfDay）+：+ Integer.toString（minute）; 
} 
} 
  

代码

  @Override 
 protected void onCreate（Bundle savedInstanceState）{
 super.onCreate（savedInstanceState）; 
 setContentView（R.layout.activity_second）; 
 
 
按钮btn =（Button）findViewById（R.id.start_time_button）; 
 Button.setText（Time）; 
 
 
} 
  

解决方案

p>首选方法是使用回调从 Fragment 获取信号。此外，这是Android在与活动通信中推荐的方法

对于您的示例，在您的 DialogFragment 中添加一个界面并注册。

public $静态接口OnCompleteListener {
public abstract void onComplete（String time）;
}

private OnCompleteListener mListener;

//确保Activity实现了
@Override
public void onAttach（Activity activity）{
super.onAttach（activity）;
尝试{
this.mListener =（OnCompleteListener）活动;
}
catch（final ClassCastException e）{
throw new ClassCastException（activity.toString（）+必须实现OnCompleteListener）;
}
}

现在实现这个界面在您的活动

  public class MyActivity extends Activity implements MyDialogFragment.OnCompleteListener { 
 // ... 
 
 public void onComplete（String time）{
 //对话片段完成后，它调用此回调。 
 //使用字符串
} 
} 
  

现在在您的 DialogFragment 中，当用户单击确定按钮时，通过您的回调将该值发送回活动。 / p>

  public void onTimeSet（TimePicker view，int hourOfDay，int minute）{
 String time = Integer.toString（hourOfDay） +：+ Integer.toString（minute）; 
 this.mListener.onComplete（time）; 
} 
  

I have read many posts on this but I can't find any that apply to this case.

I have a time picker dialog and I have put the integer values together in a string and I need to get this string back to the main activity.

This string value will then be used to set the text of a button.

If someone could help me with this it would be most appreciated.

Thank you

Dialog Fragment

public class TimePickerFragment extends DialogFragment implements TimePickerDialog.OnTimeSetListener {
    @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);

        // Create a new instance of TimePickerDialog and return it
        return new TimePickerDialog(getActivity(), this, hour, minute, DateFormat.is24HourFormat(getActivity()));
    }

    public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
        // Do something with the time chosen by the user
        String Time =Integer.toString(hourOfDay) + " : " + Integer.toString(minute);
    }
}

Code

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);


        Button btn = (Button) findViewById(R.id.start_time_button);
        Button.setText(Time);


    }

解决方案

The preferred method is to use a callback to get a signal from a Fragment. Also, this is the recommended method proposed by Android at Communicating with the Activity

For your example, in your DialogFragment, add an interface and register it.

public static interface OnCompleteListener {
    public abstract void onComplete(String time);
}

private OnCompleteListener mListener;

// make sure the Activity implemented it
@Override
public void onAttach(Activity activity) {
    super.onAttach(activity); 
    try {
        this.mListener = (OnCompleteListener)activity;
    }
    catch (final ClassCastException e) {
        throw new ClassCastException(activity.toString() + " must implement OnCompleteListener");
    }
}

Now implement this interface in your Activity

public class MyActivity extends Activity implements MyDialogFragment.OnCompleteListener {
    //...

    public void onComplete(String time) {
        // After the dialog fragment completes, it calls this callback.
        // use the string here
    }
}

Now in your DialogFragment, when a user clicks the OK button, send that value back to the Activity via your callback.

public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
    String time = Integer.toString(hourOfDay) + " : " + Integer.toString(minute);
    this.mListener.onComplete(time);
}

这篇关于从对话框片段返回字符串返回到活动的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！