Android 我可以在运行时在listview中插入列吗?
我想让listview看起来像android中的datagrid控件。所有列都是由动态的代码behand生成的。我的代码片段可以成功生成,但listview没有如我预期的那样显示。它有什么问题Android 我可以在运行时在listview中插入列吗?,android,listview,Android,Listview,我想让listview看起来像android中的datagrid控件。所有列都是由动态的代码behand生成的。我的代码片段可以成功生成,但listview没有如我预期的那样显示。它有什么问题 @Override public View getView(int position, View convertView, ViewGroup parentView) { ViewHolder holder = null; if (c
@Override
public View getView(int position, View convertView, ViewGroup parentView) {
ViewHolder holder = null;
if (convertView == null) {
synchronized (MainActivity.this) {
convertView = mInflater.inflate(id_row_layout, null);
holder = new ViewHolder();
//I had add an textView to the convertView,but it not show
LinearLayout layout = (LinearLayout) convertView.findViewById(R.id.rLayout);
TextView tx = new TextView(context);
tx.setText("ads");
layout.addView(tx);
MyHScrollView scrollView1 = (MyHScrollView) convertView
.findViewById(R.id.horizontalScrollView1);
holder.scrollView = scrollView1;
holder.txt1 = (TextView) convertView
.findViewById(R.id.textView1);
holder.txt2 = (TextView) convertView
.findViewById(R.id.textView2);
holder.txt3 = (TextView) convertView
.findViewById(R.id.textView3);
holder.txt4 = (TextView) convertView
.findViewById(R.id.textView4);
holder.txt5 = (TextView) convertView
.findViewById(R.id.textView5);
MyHScrollView headSrcrollView = (MyHScrollView) mHead
.findViewById(R.id.horizontalScrollView1);
headSrcrollView
.AddOnScrollChangedListener(new OnScrollChangedListenerImp(
scrollView1));
convertView.setTag(holder);
mHolderList.add(holder);
}
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.txt1.setText(position + "" + 1);
holder.txt2.setText(position + "" + 2);
holder.txt3.setText(position + "" + 3);
holder.txt4.setText(position + "" + 4);
holder.txt5.setText(position + "" + 5);
return convertView;
}
在ApiDemos中使用额外的文本视图为我工作
public class List14 extends ListActivity {
private static class EfficientAdapter extends BaseAdapter {
private LayoutInflater mInflater;
private Bitmap mIcon1;
private Bitmap mIcon2;
private Context context;
public EfficientAdapter(Context context) {
// Cache the LayoutInflate to avoid asking for a new one each time.
mInflater = LayoutInflater.from(context);
this.context = context;
// Icons bound to the rows.
mIcon1 = BitmapFactory.decodeResource(context.getResources(), R.drawable.icon48x48_1);
mIcon2 = BitmapFactory.decodeResource(context.getResources(), R.drawable.icon48x48_2);
}
/**
* The number of items in the list is determined by the number of speeches
* in our array.
*
* @see android.widget.ListAdapter#getCount()
*/
public int getCount() {
return DATA.length;
}
/**
* Since the data comes from an array, just returning the index is
* sufficent to get at the data. If we were using a more complex data
* structure, we would return whatever object represents one row in the
* list.
*
* @see android.widget.ListAdapter#getItem(int)
*/
public Object getItem(int position) {
return position;
}
/**
* Use the array index as a unique id.
*
* @see android.widget.ListAdapter#getItemId(int)
*/
public long getItemId(int position) {
return position;
}
/**
* Make a view to hold each row.
*
* @see android.widget.ListAdapter#getView(int, android.view.View,
* android.view.ViewGroup)
*/
public View getView(int position, View convertView, ViewGroup parent) {
// A ViewHolder keeps references to children views to avoid unneccessary calls
// to findViewById() on each row.
ViewHolder holder;
// When convertView is not null, we can reuse it directly, there is no need
// to reinflate it. We only inflate a new View when the convertView supplied
// by ListView is null.
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_item_icon_text, null);
// Creates a ViewHolder and store references to the two children views
// we want to bind data to.
holder = new ViewHolder();
holder.text = (TextView) convertView.findViewById(R.id.text);
holder.icon = (ImageView) convertView.findViewById(R.id.icon);
LinearLayout layout = (LinearLayout) convertView.findViewById(R.id.layout);
TextView child = new TextView(context);
child.setText("CHILD");
layout.addView(child);
convertView.setTag(holder);
} else {
// Get the ViewHolder back to get fast access to the TextView
// and the ImageView.
holder = (ViewHolder) convertView.getTag();
}
// Bind the data efficiently with the holder.
holder.text.setText(DATA[position]);
holder.icon.setImageBitmap((position & 1) == 1 ? mIcon1 : mIcon2);
return convertView;
}
static class ViewHolder {
TextView text;
ImageView icon;
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setListAdapter(new EfficientAdapter(this));
}
private static final String[] DATA = {
"Abbaye de Belloc", "Abbaye du Mont des Cats", "Abertam",
};
}
检查您的静态
支架
和布局
很容易有一个额外的列,只需显示和隐藏选定位置的元素即可。一旦元素未显示,就必须隐藏它们
事实上,你也可以从你的适配器中充气,但这可能会更难实现
如果您的行文件布局对每一行都相同,希望这对您有所帮助 您只需添加项目编号(即您的列) 到您的
ArrayList
(负责填充列表视图适配器
),只需调用notifydatasetchanged(true)
或适配器。notifydatasetchanged()
示例代码:据我所知,如果我们不能在xml中动态添加视图,那么您的响应就不可能了,我想加载数据以显示为datagrid。我尝试过tablelayout解决方案,但效果很慢。我必须使用listview,但我的sqlite表是通过对象生成的。那么还有其他解决方案吗?
1) In your adapter with Arraylist override the appropriate constructor
2) In your activity, make your variable data a field (type ArrayList
3) When you add a location you can use data.add(location)
4) Then you can call notifyDatasetChanged() on your adapter