您好我拥有来自网络服务的数据和图片。使用AsynTask获取所有数据，并使用延迟加载程序类获取图像，并在Splash屏幕后显示listview.here中的数据，主屏幕数据显示在列表视图。
但是在listview中滚动时出现了一些问题，它不能正常运行。
我的适配器java文件
public class NewsScreenAdapter extends BaseAdapter implements OnTouchListener,Handler.Callback {
LayoutInflater inflater;
// public GifDecoderView webview1;
public static viewholder holder;
View view = null;
public Context context;
public ImageLoader IL;
public String imgUrl;
public static String addurl;
public Activity activity;
String image;
public static String str;
public static Date parsed;
public static String ac, cat_id;
private WebViewClient client;
public NewsScreenAdapter(NewsScreenActivity a) {
// TODO Auto-generated constructor stub
this.context = a.getApplicationContext();
this.activity = a;
inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
IL = new ImageLoader(activity.getApplicationContext());
}
@Override
public int getCount() {
// TODO Auto-generated method stub
// return NewsScreenActivity.arrayList_header.size();
return NewsScreenActivity.TotalDataArray.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public int getItemViewType(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public int getViewTypeCount() {
// TODO Auto-generated method stub
return NewsScreenActivity.TotalDataArray.size();
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
View vi = convertView;
holder = new viewholder();
vi = inflater.inflate(R.layout.newsscren_row, null);
holder.news_header_title = (TextView) vi.findViewById(R.id.header_title);
holder.ll_data = (LinearLayout) vi.findViewById(R.id.data);
vi.setTag(holder);
// ------- set custom Font-----
Typeface typefont=Typeface.createFromAsset(context.getAssets(),"Times New Roman.ttf");
holder.news_header_title.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
cat_id = NewsScreenActivity.arrayList_header.get(position);
ac = ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray.get(position)).catId;
activity.startActivity(new Intent(activity,CategoryActivity.class).putExtra("id", ac));
}
});
holder.ll_data.removeAllViews();
// try {
int storyLenght = ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray.get(position)).storyArr.size();
/* } catch (Exception e) {
// TODO: handle exception
}*/
for (int i = 0; i < storyLenght; i++) {
view = LayoutInflater.from(activity).inflate(R.layout.sub_row, null);
holder.short_text = (TextView) view.findViewById(R.id.short_text);
holder.image = (ImageView) view.findViewById(R.id.image);
holder.des = (TextView) view.findViewById(R.id.des);
holder.date_time = (TextView) view.findViewById(R.id.date_time);
holder.llAdd = (LinearLayout) view.findViewById(R.id.sub_llAdd);
holder.imgAdd = (WebView) view.findViewById(R.id.imgAdd);
holder.imgAdd.setVerticalScrollBarEnabled(false);
holder.short_text.setTypeface(typefont);
holder.des.setTypeface(typefont);
holder.date_time.setTypeface(typefont);
holder.news_header_title.setTypeface(typefont);
try{
holder.image.setTag(NewsScreenActivity.arrayList_image.get(i));
IL.DisplayImage(
((NewsScreenActivity.ImagesData) ((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).storyArr.get(i)).imageArr.get(0)).smallurl, holder.image);
notifyDataSetChanged();
} catch (Exception e) {
// TODO: handle exception
}
try {
holder.short_text.setText(((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray.get(position)).storyArr.get(i)).title);
holder.des.setText(((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray.get(position)).storyArr.get(i)).description);
String st = ((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).storyArr.get(i)).date;
parsed = new Date(Long.parseLong(st.substring(6, st.length() - 2)));
SimpleDateFormat sdf = new SimpleDateFormat("MMM dd,yyyy hh:mmaa");
String concat = sdf.format(parsed);
String data = concat;
String half1 = data.substring(0, 11);
SimpleDateFormat display_date = new SimpleDateFormat("dd.MM.yyyy");
String dis_date = display_date.format(parsed);
String half2 = data.substring(11, 19);
SimpleDateFormat currentdate = new SimpleDateFormat("MMM dd,yyyy");
Date currunt = new Date();
String day = currentdate.format(currunt);
if (half1.equalsIgnoreCase(day) == true) {
holder.date_time.setText(half2);
} else {
half1 = dis_date;
holder.date_time.setText(half1);
}
holder.news_header_title.setText(((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).catDisplay);
if (!((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).storyArr.get(i)).advertising
.equalsIgnoreCase("null")) {
holder.short_text.setVisibility(view.GONE);
holder.date_time.setVisibility(view.GONE);
holder.des.setVisibility(view.GONE);
imgUrl = ((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).storyArr.get(i)).adData.imageurl;
// TODO Auto-generated method stub
addurl = ((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray
.get(position)).storyArr.get(i)).adData.targeturl;
//-----------------GIF Image view ------------
holder.imgAdd.setOnTouchListener(NewsScreenAdapter.this);
client = new WebViewClient(){
@Override public boolean shouldOverrideUrlLoading(WebView view, String url) {
handler.sendEmptyMessage(CLICK_ON_URL);
return false;
}
};
holder.imgAdd.setWebViewClient(client);
holder.imgAdd.setVerticalScrollBarEnabled(false);
// view.setVerticalScrollBarEnabled(false);
holder.imgAdd.getSettings().setJavaScriptEnabled(true);
holder.imgAdd.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView view, int progress)
{
activity.setProgress(progress * 100);
if(progress == 100){}
}
});
holder.imgAdd.setWebViewClient(new WebViewClient() {
@Override
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl)
{
// Handle the error
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url)
{
view.loadUrl(url);
return true;
}
});
holder.imgAdd.loadUrl(imgUrl);
// holder.imgAdd.setPadding(30, 20, 0, 20);
holder.llAdd.setVisibility(View.VISIBLE);
}
holder.ll_data.addView(view);
view.setTag(position+"OK"+i);
view.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
String tag = (String) v.getTag();
String[] arr = tag.split("OK");
int p = Integer.parseInt(arr[0]);
int i = Integer.parseInt(arr[1]);
str = ((NewsScreenActivity.StoryData) ((NewsScreenActivity.MainData) NewsScreenActivity.TotalDataArray .get(p)).storyArr.get(i)).storyid;
Intent intent = new Intent(context,ShowFullDescriprion.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.putExtra("id", str);
intent.putExtra("cat", p);
intent.putExtra("pos",i);
activity.startActivity(intent);
}
});
} catch (Exception e) {
// TODO: handle exception
}
}
return vi;
}
public static String getDate(long milliSeconds, String dateFormat) {
// Create a DateFormatter object for displaying date in specified
// format.
DateFormat formatter = new SimpleDateFormat(dateFormat);
// Create a calendar object that will convert the date and time value in
// milliseconds to date.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(milliSeconds);
return formatter.format(calendar.getTime());
}
public static class viewholder {
TextView news_header_title, short_text, des, date_time;
LinearLayout ll_data, llAdd;
public ImageView image;
WebView imgAdd;
}
private static final int CLICK_ON_WEBVIEW = 1;
private static final int CLICK_ON_URL = 2;
private Handler handler = new Handler(NewsScreenAdapter.this);
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if (v.getId() == R.id.imgAdd && event.getAction() == MotionEvent.ACTION_DOWN){
handler.sendEmptyMessageDelayed(CLICK_ON_WEBVIEW, 500);
}
return false;
}
public boolean handleMessage(Message msg) {
if (msg.what == CLICK_ON_URL){
handler.removeMessages(CLICK_ON_WEBVIEW);
return true;
}
if (msg.what == CLICK_ON_WEBVIEW){
activity.startActivity(new Intent(activity, AdvertismentActivity.class).putExtra("id", addurl));
return true;
}
return false;
}
/* public void clearAllResources() {
// Set related variables null
System.gc();
Runtime.getRuntime().gc();
}*/
}
答案 0 :(得分：2)
ListView滚动的核心是getView（）方法 优化getView（）方法将导致更快/更顺畅的滚动。 有一些技术，描述in this video。你有一个视频，如果你没有时间看它，你有一个 pdf供下载。
简而言之，它教你如何避免在每次调用getView（）时创建对象（如果不需要的话）。
你的getView（）创建总是一个TextView，一个LinearLayout和一个Typeface。只有当convertview为null时才应该创建所有这些，如果不是，则视图已经存在且可以重复使用
在链接中查找pdf中的推荐代码。
答案 1 :(得分：1)
建议1：
从getView方法notifyDataSetChanged();
在其getView方法中更新适配器的编码真的很差。
建议2：
每次进入获取视图时都不要重新创建所有内容。
如果已创建视图，则只需使用它。
检查此代码：Update Adapter Code