我在更改ListView中视图的背景时遇到问题。
我需要什么:
更改onClick()
实际发生的事情:
在按下例如后,背景被改变(选择)第一个条目。但在向下滚动后,也会选择第8个条目。
滚动回到顶部,第一个不再被选中。现在选择第二个条目。
继续滚动,继续跳...
我在守则中的内容:
我有频道和onClick()我切换频道布尔选择的属性
然后我改变了背景。
我正在做仅 onClick()这就是为什么我不明白为什么它也会在其他条目上发生。
我注意到的一件事是:它似乎只是“绘图” - 部分,因为“通过它自己”选择的项目在错误 <上仍然具有选定的值/ p>
我认为这似乎与自定义ListAdapters getView(...)
中的视图重用有关ListActivity中的onClick()代码:
@Override
protected ViewHolder createHolder(View v) {
// createHolder will be called only as long, as the ListView is not
// filled
TextView title = (TextView) v
.findViewById(R.id.tv_title_channel_list_adapter);
TextView content = (TextView) v
.findViewById(R.id.tv_content_channel_list_adapter);
ImageView icon = (ImageView) v
.findViewById(R.id.icon_channel_list_adapter);
if (title == null || content == null || icon == null) {
Log.e("ERROR on findViewById",
"Couldn't find Title, Content or Icon");
}
ViewHolder mvh = new MyViewHolder(title, content, icon);
// We make the views become clickable
// so, it is not necessary to use the android:clickable attribute in
// XML
v.setOnClickListener(new ChannelListAdapter.OnClickListener(mvh) {
public void onClick(View v, ViewHolder viewHolder) {
// we toggle the enabled state and also switch the the
// background
MyViewHolder mvh = (MyViewHolder) viewHolder;
Channel ch = (Channel) mvh.data;
ch.setSelected(!ch.getSelected()); // toggle
if (ch.getSelected()) {
v.setBackgroundResource(R.drawable.row_blue_selected);
} else {
v.setBackgroundResource(R.drawable.row_blue);
}
// TESTING
Log.d("onClick() Channel", "onClick() Channel: "
+ ch.getTitle() + " selected: " + ch.getSelected());
}
});
return mvh;
}
getView代码(...):
@Override
public View getView(int position, View view, ViewGroup parent) {
ViewHolder holder;
// When view is not null, we can reuse it directly, there is no need
// to reinflate it.
// We only inflate a new View when the view supplied by ListView is
// null.
if (view == null) {
view = mInflater.inflate(mViewId, null);
// call own implementation
holder = createHolder(view);
// TEST
// we set the holder as tag
view.setTag(holder);
} else {
// get holder back...much faster than inflate
holder = (ViewHolder) view.getTag();
}
// we must update the object's reference
holder.data = getItem(position);
// <EDIT SOLUTION>
if(getItem(position).get_id() == channelList.get(position).get_id()){
if(getItem(position).getSelected())
{
view.setBackgroundResource(R.drawable.row_blue_selected);
}
else{
view.setBackgroundResource(R.drawable.row_blue);
}
}
// </EDIT SOLUTION>
// call the own implementation
bindHolder(holder);
return view;
}
我真的很感激任何想法如何解决这个问题! :)
如果需要更多信息,请告诉我。
提前致谢!
答案 0 :(得分:10)
让我向您展示我为每个ListView
使用的代码,并正确控制click事件以更改背景并进行更多操作
public class Offices extends Activity {
private ListView listView;
/* selectedListItem will contain the number of items to be selected.
* Your list item OnOlickListener will simply change this variable
* to the position of the clicked item. The Adapter will do the rest
* because you need to refresh the ListView.
*/
private int selectedListItem = -1;
private Handler mHandler = new Handler();
private Vector<String> data;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.officeslayout);
data = new Vector<String>();
// Add data as per your requirement
data.add("one");
data.add("two");
data.add("three");
data.add("four");
data.add("Five");
data.add("Six");
data.add("Seven");
data.add("Eight");
data.add("Nine");
data.add("Ten");
listView = (ListView)findViewById(R.id.ListView01);
listView.setDivider(null);
listView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
selectedListItem = position;
((EfficientAdapter)listView.getAdapter()).notifyDataSetChanged();
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
// call any new activity here or do any thing you want here
}
}, 200L);
}
});
listView.setAdapter(new EfficientAdapter(getApplicationContext()));
}
private class EfficientAdapter extends BaseAdapter {
private LayoutInflater mInflater;
public EfficientAdapter(Context context) {
mInflater = LayoutInflater.from(context);
}
public int getCount() {
return data.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null || convertView.getTag() == null) {
convertView = mInflater.inflate(R.layout.officeslistitemlayout, null);
holder = new ViewHolder();
holder.backgroundView = (ImageView) convertView
.findViewById(R.id.OfficesBackground);
holder.officesTitle = (TextView) convertView
.findViewById(R.id.OfficesName);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
if(position == selectedListItem) {
holder.backgroundView.setBackgroundResource(R.drawable.and_gray_bg_listing_selected);
} else {
holder.backgroundView.setBackgroundResource(R.drawable.and_gray_bg_listing);
}
holder.officesTitle.setText(data.get(position));
return convertView;
}
}
static class ViewHolder {
TextView officesTitle;
ImageView backgroundView;
}
}
<ImageView android:id="@+id/OfficesBackground" android:layout_width="fill_parent"
android:layout_height="45dip"
android:layout_alignParentTop="true"
android:background="@drawable/and_gray_bg_listing"
android:scaleType="fitXY"
></ImageView>
<TextView android:id="@+id/OfficesName" android:layout_width="wrap_content"
android:text="Offices Name"
android:textColor="#000000" android:textStyle="bold"
android:layout_height="wrap_content"
android:layout_centerVertical="true" android:layout_marginLeft="5dip"
></TextView>
希望它会有所帮助:)