如何从另一个片段类访问方法?

时间:2013-03-27 06:07:25

标签: android methods nullpointerexception fragment

我希望从另一个片段调用一个方法,但它一直告诉我TextViews的值是null。?

PLAYER1:

public class PlayerTurn1 extends Fragment  {

    TextView p1Name;
    TextView p1Icon;
    Button doneP1;
    Button resetP1;
    EditText row;
    EditText column;
    TicTacToeLayout myObject = new TicTacToeLayout();
    ArrayList<String> player1;
    Bundle extras = new Bundle();
    int turn = 1;

public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

       extras = getArguments();

       player1 = new ArrayList<String>(extras.getStringArrayList("player1"));

       Toast.makeText(getActivity(), player1.get(0), Toast.LENGTH_LONG).show();//Name of the player
       Toast.makeText(getActivity(), player1.get(1), Toast.LENGTH_LONG).show();//Icon chosen by the player

        row = (EditText) getActivity().findViewById(R.id.rowP1);
        column = (EditText) getActivity().findViewById(R.id.columnP1);
        p1Name = (TextView) getActivity().findViewById(R.id.p1NameInfo);
        p1Icon = (TextView) getActivity().findViewById(R.id.p1IconInfo);
        doneP1 = (Button) getActivity().findViewById(R.id.doneP1);
        resetP1 = (Button) getActivity().findViewById(R.id.resetP2);

        setPlayer();


        doneP1.setOnClickListener(new View.OnClickListener() {          
            public void onClick(View v) {   

                if(checkField() != false)
                {
                     int rowValueInt = Integer.parseInt(row.getText().toString());
                     int colValueInt = Integer.parseInt(column.getText().toString());

                    myObject.play(rowValueInt, colValueInt, player1.get(1));
                    callPlayer2Fragment();

                }


            }
        });
    }

播放器2片段的代码完全相同,所以我不打算添加它。

TicTacToeLayout片段类:

public class TicTacToeLayout extends Fragment {

    TextView image1, image2, image3, image4, image5, image6, image7, image8, image9;
    TextView[][] images;


    public View onCreateView(LayoutInflater inflater,
    ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.tictactoe_layout, container, false);
    }

    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);


        image1 = (TextView) getActivity().findViewById(R.id.Image1);
        image2 = (TextView) getActivity().findViewById(R.id.Image2);
        image3 = (TextView) getActivity().findViewById(R.id.Image3);
        image4 = (TextView) getActivity().findViewById(R.id.Image4);
        image5 = (TextView) getActivity().findViewById(R.id.Image5);
        image6 = (TextView) getActivity().findViewById(R.id.Image6);
        image7 = (TextView) getActivity().findViewById(R.id.Image7);
        image8 = (TextView) getActivity().findViewById(R.id.Image8);
        image9 = (TextView) getActivity().findViewById(R.id.Image9);

        images = new TextView[][]{ {image1, image2, image3},
                                   {image4, image5, image6},
                                   {image7, image8, image9} };

        toast();
    }

    public void toast()
    {
        Toast.makeText(getActivity(), images[0][0].getText().toString(), Toast.LENGTH_LONG).show();
        Toast.makeText(getActivity(), images[0][1].getText().toString(), Toast.LENGTH_LONG).show();
        Toast.makeText(getActivity(), images[0][2].getText().toString(), Toast.LENGTH_LONG).show();
        Toast.makeText(getActivity(), images[1][0].getText().toString(), Toast.LENGTH_LONG).show();
    }

    public void play(int row, int column, String icon)
    {
            images[row-1][column-1].setText(icon);
    }

}

我刚刚制作了一个尝试吐司的方法,只是为了确保数组中有某些内容并且有效。但是,只有在创建片段时才会干杯。不知何故,在方法调用myObject.play(rowValueInt, colValueInt, player1.get(1));之后 调试器告诉我,我的图像的所有值都是空的。

这是调试器所说的:

this    TicTacToeLayout  (id=830016401072)  
    image1  null    
    image2  null    
    image3  null    
    image4  null    
    image5  null    
    image6  null    
    image7  null    
    image8  null    
    image9  null    
    images  null    

row 1   
column  2   
icon    "O" (id=830016398920)   

当我点击完成按钮时,这基本上就会发生。应该发生的事情是当玩家点击按钮时,在TicTacToeLayout片段中,位于任何行和列的文本视图被播放的玩家改变为X或O. 行,列和图标都有各自的值,但是在调用对象后图像最终为null。有任何想法吗?我的帖子已被关闭,因为显然我没有提供太多信息而且管理员很生气,所以如果你还需要其他任何东西,请告诉我我会更新。

修改 调用位于PlayerTurn1中的第二个玩家片段

public void callPlayer2Fragment()
    {
        FragmentManager fm       = getFragmentManager();
        FragmentTransaction ft = fm.beginTransaction();
        Fragment Player2Frag = new PlayerTurn2();
        Player2Frag.setArguments(extras);
        ft.replace(R.id.fragment_container, Player2Frag);
        ft.commit();
    }

单击完成按钮时,将调用PlayerTurn2片段并传递此类中的参数,但会替换此片段。

XML布局

<?xml version="1.0" encoding="UTF-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="horizontal" >

        <FrameLayout
         android:id="@+id/fragment_container"
         android:layout_width="0px"
         android:layout_height="match_parent" 
         android:layout_weight="1" />

        <fragment
            android:id="@+id/frag2"
            android:name="As2.packageTK.TicTacToeLayout"
            android:layout_width="0px"
            android:layout_height="match_parent"
            android:layout_weight="1" />

    </LinearLayout>

1 个答案:

答案 0 :(得分:0)

它们全部为空的原因是因为片段当前不是“活着的”(即附加或创建)。您应该通过Activity中的界面来完成。我解释一下here