java - onClick fragment 找不到方法

Question

我正在尝试创建一个 ToDo 列表。我承认我仍在学习如何使用 fragment ，但我认为我的问题与 fragment 的设计方式存在冲突。现在我有一个任务 fragment 。我将在哪里添加任务，下面有一个列表。当我输入时，我单击添加按钮，它应该显示在列表中。我还有一个 list_inner_view，其中有一个复选框。

现在在 xml 中我调用了 android:onClick = "addTaskNow"方法。

这是我的代码。

我的 fragment_tasks.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".FragmentTasks" >

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:ems="10" >

        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="14dp"
        android:text="Add" 
        android:onClick="addTaskNow"/>

    <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/button1" >
    </ListView>

</RelativeLayout>

我的 FragmentTasks.java

package com.example.navbar;

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;

/**
 * A simple {@link Fragment} subclass.
 * 
 */
public class FragmentTasks extends Fragment {

    public FragmentTasks() {
        // Required empty public constructor
    }

    protected TaskerDbHelper db;
    List<Task> list;
    MyAdapter adapt;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View rootView = inflater.inflate(R.layout.fragment_tasks, container, false);
        //return inflater.inflate(R.layout.fragment_tasks, container, false);
        db = new TaskerDbHelper(getActivity());
        list = db.getAllTasks();
        adapt = new MyAdapter(getActivity(), R.layout.list_inner_view, list);
        ListView listTask = (ListView) rootView.findViewById(R.id.list);
        listTask.setAdapter((ListAdapter) adapt);

        Button b = (Button) rootView.findViewById(R.id.button1);
        return rootView;
    }


    public void addTaskNow(View v) {
        EditText t = (EditText) v.findViewById(R.id.editText1);


        String s = t.getText().toString();
        if (s.equalsIgnoreCase("")) {
            Toast.makeText(getActivity(), "enter the task description first!!",
                    Toast.LENGTH_LONG);
        } else {
            Task task = new Task(s, 0);
            db.addTask(task);
            Log.d("tasker", "data added");
            t.setText("");
            adapt.add(task);
            adapt.notifyDataSetChanged();
        }

    }

    private class MyAdapter extends ArrayAdapter<Task> {

        Context context;
        List<Task> taskList = new ArrayList<Task>();
        int layoutResourceId;

        public MyAdapter(Context context, int layoutResourceId,
                List<Task> objects) {
            super(context, layoutResourceId, objects);
            this.layoutResourceId = layoutResourceId;
            this.taskList = objects;
            this.context = context;
        }

        /**
         * This method will DEFINe what the view inside the list view will
         * finally look like Here we are going to code that the checkbox state
         * is the status of task and check box text is the task name
         */
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            CheckBox chk = null;
            if (convertView == null) {
                LayoutInflater inflater = (LayoutInflater) context
                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.list_inner_view,
                        parent, false);
                chk = (CheckBox) convertView.findViewById(R.id.checkBox1);
                convertView.setTag(chk);

                chk.setOnClickListener(new View.OnClickListener() {

                    @Override
                    public void onClick(View v) {
                        CheckBox cb = (CheckBox) v;
                        Task changeTask = (Task) cb.getTag();
                        changeTask.setStatus(cb.isChecked() == true ? 1 : 0);
                        db.updateTask(changeTask);
                        /*Toast.makeText(
                                getApplicationContext(),
                                "Clicked on Checkbox: " + cb.getText() + " is "
                                        + cb.isChecked(), Toast.LENGTH_LONG)
                                .show();
                    } */

                }});
            } else {
                chk = (CheckBox) convertView.getTag();
            }
            Task current = taskList.get(position);
            chk.setText(current.getTaskName());
            chk.setChecked(current.getStatus() == 1 ? true : false);
            chk.setTag(current);
            Log.d("listener", String.valueOf(current.getId()));
            return convertView;


    }




}}

Answer 1

方法“addTaskNow”需要在 fragment 被添加到的 Activity 中。如果您希望 fragment 处理点击，您需要将点击监听器转发给 fragment ，或者在 fragment 内设置点击监听器。 onClick 仅适用于 Activity ，不适用于 fragment 。