android - 无法在选项卡 Activity 上设置 OnListItemClick

Question

我想用标签栏做一个 Activity ，我有 5 个标签菜单。 MainActivity 包括像这样的 Tabhost；

public class MainActivity extends TabActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.activity_main);

    String tab_title[] = { "Tab 1", "Tab 2", "Tab 3", "Tab 4", "Tab 5" };

    int tab_drawables[] = { R.drawable.menu_bookmark,
            R.drawable.menu_filemanager, R.drawable.menu_download,
            R.drawable.menu_sharepage, R.drawable.menu_about };

    Object tab_act[] = { Tab1.class, Tab2.class, Tab3.class, Tab4.class, Tab5.class };

    final TabHost tabHost = (TabHost) findViewById(android.R.id.tabhost);
    tabHost.setup();

    TabSpec tab_spec;

    for (int i = 0; i < tab_act.length; i++) {
        tab_spec = tabHost.newTabSpec(tab_title[i]);
        tab_spec.setIndicator(tab_title[i],
                getResources().getDrawable(tab_drawables[i]));
        tab_spec.setContent(new Intent(this, (Class<?>) tab_act[i]));
        tabHost.addTab(tab_spec);
    }
    tabHost.setCurrentTab(0);

}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        MainActivity.this.finish();
        return true;
    }
    return super.onKeyDown(keyCode, event);
}

当我点击 Tab2 时，将调用 Tab2.java 类。这个类有一个 ListView 。当我点击列表项时，我想在 youtube 上播放音乐。我的代码有效，但 OnListItemClick 方法无效。

public class Tab2 extends Activity{

private LayoutInflater mInflater;
private Vector<RowData> data;
RowData rd;
Context context ;
Bitmap bitmap;

public static String title[] = { "song 1", "song 2", "song 3"};

@Override
protected void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.tab2);
    super.onCreate(savedInstanceState);

    mInflater = (LayoutInflater) getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    data = new Vector<RowData>();
    for (int i = 0; i < title.length; i++) {
        try {
                rd = new RowData(i, title[i]);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        data.add(rd);
    }
    CustomAdapter adapter = new CustomAdapter(this,
            R.layout.activity_list_view, R.id.title, data);
}

private class RowData {
    protected int mId;
    protected String mTitle;

    RowData(int id, String title) {
        mId = id;
        mTitle = title;
    }

    @Override
    public String toString() {
        return mId + " " + mTitle;
    }
}

public void onListItemClick(ListView parent, View v, int position, long id) {
    if (position == 0) {
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=QK8mJJJvaes")));
    }
    else if (position == 1) {
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=HWyEEj2pSt0")));
    }   
    else if (position == 2){
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=HWyEEj2pSt0")));
    }
}

private class CustomAdapter extends ArrayAdapter<RowData> {
    public CustomAdapter(Context context, int resource,
            int textViewResourceId, List<RowData> objects) {
        super(context, resource, textViewResourceId, objects);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = null;
        TextView title = null;
        RowData rowData = getItem(position);
        if (null == convertView) {
            convertView = mInflater
                    .inflate(R.layout.activity_list_view, null);
            holder = new ViewHolder(convertView);
            convertView.setTag(holder);
        }
        holder = (ViewHolder) convertView.getTag();
        title = holder.gettitle();
        title.setText(rowData.mTitle);

        return convertView;
    }

    private class ViewHolder {
        private View mRow;
        private TextView title = null;
        private ImageView i11 = null;

        public ViewHolder(View row) {
            mRow = row;
        }

        public TextView gettitle() {
            if (null == title) {
                title = (TextView) mRow.findViewById(R.id.title);
            }
            return title;
        }

    }   
}

我对布局没有问题，我对此很确定，所以不需要显示我的 xml 文件。 :)

已更新

我用以下代码更改 Tab2 类；

public class Tab2 extends Activity implements AdapterView.OnItemClickListener{

private LayoutInflater mInflater;
private Vector<RowData> data;
RowData rd;
Context context ;
Bitmap bitmap;

public static String title[] = { "song 1", "song 2", "song 3"};

@Override
protected void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.tab2);
    super.onCreate(savedInstanceState);

    mInflater = (LayoutInflater) getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    data = new Vector<RowData>();
    for (int i = 0; i < title.length; i++) {
        try {
                rd = new RowData(i, title[i]);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        data.add(rd);
    }
    CustomAdapter adapter = new CustomAdapter(this,
            R.layout.activity_list_view, R.id.title, data);

    ListView list = (ListView) findViewById(R.id.list);
    list.setAdapter(adapter);
    list.setOnItemClickListener(this);
}

private class RowData {
    protected int mId;
    protected String mTitle;

    RowData(int id, String title) {
        mId = id;
        mTitle = title;
    }

    @Override
    public String toString() {
        return mId + " " + mTitle;
    }
}


private class CustomAdapter extends ArrayAdapter<RowData> {
    public CustomAdapter(Context context, int resource,
            int textViewResourceId, List<RowData> objects) {
        super(context, resource, textViewResourceId, objects);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = null;
        TextView title = null;
        RowData rowData = getItem(position);
        if (null == convertView) {
            convertView = mInflater
                    .inflate(R.layout.activity_list_view, null);
            holder = new ViewHolder(convertView);
            convertView.setTag(holder);
        }
        holder = (ViewHolder) convertView.getTag();
        title = holder.gettitle();
        title.setText(rowData.mTitle);

        return convertView;
    }

    private class ViewHolder {
        private View mRow;
        private TextView title = null;
        private ImageView i11 = null;

        public ViewHolder(View row) {
            mRow = row;
        }

        public TextView gettitle() {
            if (null == title) {
                title = (TextView) mRow.findViewById(R.id.title);
            }
            return title;
        }

    }   
}

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    // TODO Auto-generated method stub
    if (position == 0) {
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=4jHrdLUFA-8")));
    }
    else if (position == 1) {
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=-HMfKUtYHog")));
    }   
    else if (position == 2){
        startActivity(new Intent(Intent.ACTION_VIEW,Uri.parse("http://www.youtube.com/watch?v=7beBw8uQOR8")));
    }
}

Answer 1

public class Tab2 extends Activity

Tab2 扩展 Activity，而不是 ListActivity。

要让它正常工作，请在 R.layout.tab2 中找到 ListView 小部件:

super.onCreate(savedInstanceState);
setContentView(R.layout.tab2);    

mInflater = (LayoutInflater) getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

data = new Vector<RowData>();
for (int i = 0; i < title.length; i++) {
    try {
            rd = new RowData(i, title[i]);
    } catch (ParseException e) {
        e.printStackTrace();
    }
    data.add(rd);
}

CustomAdapter adapter = new CustomAdapter(this,
        R.layout.activity_list_view, R.id.title, data);

ListView lv = (ListView) findViewById(R.id.your_listiew_id);
lv.setAdapter(adapter);

lv.setOnItemClickListener(this);

将您的类定义更改为:

public class Tab2 extends Activity implements AdapterView.OnItemClickListener {

并将 onListItemClick(ListView parent, View v, int position, long id) 更改为:

@Override
public void onItemClick((AdapterView<?> parent, View view, int position, long id) 

您的代码存在的问题是您从未将 OnItemClickListener 分配给 ListView。如果你想使用 onListItemClick (ListView l, View v, int position, long id)，那么 Tab2 应该扩展 ListActivity，而不是 Activity 。要查看原因:Link .