Question

我正在使用Java和Android Studio创建我的第一个Android应用。我有一个主类和布局（在适配器的帮助下）显示章节号的列表视图。我有一个clicklistener，当点击一行时，会加载一个新的活动。但是，我想要做的是捕获一个记录单击哪一行的变量，以便我可以在新活动中加载相关内容。做这个的最好方式是什么？

MainActivity：

public class MainActivity extends AppCompatActivity {
    String[] nameArray = {"Chapter 1","Chapter 2","Chapter 3","Chapter 4","Chapter 5","Chapter 6", "Chapter 7", "Chapter 8", "Chapter 9", "Chapter 10", "Chapter 11", "Chapter 12", "Chapter 13", "Chapter 14", "Chapter 15", "Chapter 16", "Chapter 17", "Chapter 18", "Chapter 19", "Chapter 20", "Chapter 21" }; //List of chapters to display
    ListView listView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ChapterlistAdapter whatever = new ChapterlistAdapter(this, nameArray);
        listView = (ListView) findViewById(R.id.chapterListview);
        listView.setAdapter(whatever);

        // Make the row respond when clicked
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                                    long arg3) {
                // TODO Auto-generated method stub
                Log.d("dev","Its clicked" );
                goToChapter();
            }

        });
    }

    /** Called when the user taps the Send button */
    public void goToChapter() {
        Intent intent = new Intent(this, CardView.class);
        intent.putExtra(EXTRA_MESSAGE, "chapter clicked");
        startActivity(intent);
    }

ChapterlistAdapter：

public class ChapterlistAdapter extends ArrayAdapter {
    //to reference the Activity
    private final Activity context; //Stores which activity the list listview is on?
    //to store the list of countries
    private final String[] chapterArray;

    public ChapterlistAdapter(Activity context, String[] nameArrayParam){

        super(context,R.layout.chapter_listview_row , nameArrayParam);
        this.context=context;
        this.chapterArray = nameArrayParam;
    }

    public View getView(int position, View view, ViewGroup parent) {
        LayoutInflater inflater=context.getLayoutInflater();
        View rowView=inflater.inflate(R.layout.chapter_listview_row, null,true);

        //this code gets references to objects in the listview_row.xml file
        TextView nameTextField = (TextView) rowView.findViewById(R.id.chapterListviewRowText);

        //this code sets the values of the objects to values from the arrays
        nameTextField.setText(chapterArray[position]);


        return rowView;

    };
}

我的想法是在putExtra方法中传递一个变量 - 但是我不确定如何捕获该变量。我可以从MainActivity获取它吗？或者我必须在适配器类中执行此操作吗？

最终目标是知道点击了哪一章，以便显示该章的内容。

Answer 1

通过position获取点击的项目，如：

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        //get here using position  
        String selected = (String) parent.getItemAtPosition(position);                     
    }
});

如何传递哪一行的变量点击我的意图？

1 个答案: