伙计们。
我的列表视图有问题。我使用 ViewHolder 来优化性能，但我仍然得到一些列表视图滞后。你能建议吗？
这是我的 ListView XML
<ListView
android:id="@+id/list1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:divider="@android:color/transparent"
android:dividerHeight="10dp"
android:fadingEdge="none"
android:fastScrollEnabled="true"
android:headerDividersEnabled="false"
android:listSelector="@android:color/transparent"
android:scrollingCache="false" />
这也是我为回收而实施的带有 ViewHolder 的自定义 SimplecursorAdapter
public class AlternateRowCursorAdapter extends SimpleCursorAdapter {
int layoutn;
LayoutInflater mInflater;
SQLiteDatabase mDb;
MyDbHelper mHelper;
private final Cursor mCursor;
private final int mLayout;
private final LayoutInflater mLayoutInflater;
private final Context mContext;
public static final String TABLE_NAME = "MSGS";
public AlternateRowCursorAdapter(Context context, int layout, Cursor c,
String[] from, int[] to) {
super(context, R.layout.listtype, c, from, to);
this.mContext = context;
this.mCursor = c;
this.mLayout = layout;
this.mLayoutInflater = LayoutInflater.from(context);
}
private final class ViewHolder {
public TextView Title;
public ImageView one, two, three, four, five, six, seven, zina;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (mCursor.moveToPosition(position)) {
final ViewHolder viewHolder;
if (convertView == null) {
convertView = mLayoutInflater.inflate(mLayout, parent, false);
viewHolder = new ViewHolder();
viewHolder.Title = (TextView) convertView
.findViewById(R.id.Sandtit);
viewHolder.one = (ImageView) convertView
.findViewById(R.id.imageView5);
viewHolder.two = (ImageView) convertView
.findViewById(R.id.imageView4);
viewHolder.three = (ImageView) convertView
.findViewById(R.id.ImageView03);
viewHolder.four = (ImageView) convertView
.findViewById(R.id.ImageView02);
viewHolder.five = (ImageView) convertView
.findViewById(R.id.imageView1);
viewHolder.six = (ImageView) convertView
.findViewById(R.id.ImageView06);
viewHolder.seven = (ImageView) convertView
.findViewById(R.id.ImageView01);
viewHolder.zina = (ImageView) convertView
.findViewById(R.id.imageView2);
convertView.setTag(viewHolder);
}
else {
viewHolder = (ViewHolder) convertView.getTag();
}
final String Title, SandID, MsgID, MsgFav;
Title = mCursor.getString(2);
SandID = mCursor.getString(1);
MsgID = mCursor.getString(0);
MsgFav = mCursor.getString(4);
Typeface tf = Typeface.createFromAsset(mContext.getAssets(),
"fonts/khalaadsara.ttf");
viewHolder.Title.setText(Title);
viewHolder.Title.setTypeface(tf);
try {
mHelper = new MyDbHelper(mContext);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (MsgFav.contentEquals("YES")) {
viewHolder.one.setImageResource(R.drawable.favorpress);
} else {
viewHolder.one.setImageResource(R.drawable.favornorm);
}
mDb = mHelper.getWritableDatabase();
viewHolder.one.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
if (MsgFav.contentEquals("NO")) {
ContentValues args = new ContentValues();
args.put(mHelper.COL_MsgFavor, "YES");
mDb.update(TABLE_NAME, args, "_id = ?",
new String[] { MsgID });
viewHolder.one.setImageResource(R.drawable.favorpress);
Toast.makeText(
mContext,
"تم إضافة الرسالة إلي الرسائل المفضلة بنجاح...",
9000).show();
notifyDataSetChanged();
mCursor.requery();
}
else {
ContentValues args = new ContentValues();
args.put(mHelper.COL_MsgFavor, "NO");
mDb.update(TABLE_NAME, args, "_id = ?",
new String[] { MsgID });
viewHolder.one.setImageResource(R.drawable.favornorm);
Toast.makeText(mContext,
"تم حذف الرسالة من الرسائل المفضلة بنجاح...",
9000).show();
notifyDataSetChanged();
mCursor.requery();
}
}
});
viewHolder.two.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent emailIntentt = new Intent(
android.content.Intent.ACTION_VIEW);
emailIntentt.setData(Uri.parse("sms:"));
String breaks = "\n";
emailIntentt.putExtra("sms_body", Title);
mContext.startActivity(emailIntentt);
}
});
viewHolder.three.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
viewHolder.Title.setTextSize(TypedValue.COMPLEX_UNIT_PX,
(viewHolder.Title.getTextSize() - 1f));
}
});
viewHolder.four.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent emailIntentt = new Intent(
android.content.Intent.ACTION_SEND);
String breaks = "\n";
String[] recipientss = new String[] {
"من فضلك...أدخل بريدك الأليكتروني", "", };
emailIntentt.putExtra(android.content.Intent.EXTRA_EMAIL,
recipientss);
emailIntentt.putExtra(android.content.Intent.EXTRA_SUBJECT,
"مسجات رمضان 2013");
emailIntentt.putExtra(android.content.Intent.EXTRA_TEXT,
breaks + Title);
emailIntentt.setType("text/plain");
mContext.startActivity(Intent.createChooser(emailIntentt,
"مشاركة بواسطة..."));
}
});
viewHolder.five.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
ClipboardManager ClipMan = (ClipboardManager) mContext
.getSystemService(Context.CLIPBOARD_SERVICE);
ClipMan.setText(Title);
Toast.makeText(mContext, "تم نسخ الرسالة بنجاح....", 9000)
.show();
}
});
viewHolder.six.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
viewHolder.Title.setTextSize(TypedValue.COMPLEX_UNIT_PX,
(viewHolder.Title.getTextSize() + 1f));
}
});
viewHolder.seven.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent waIntent = new Intent(Intent.ACTION_SEND);
if (waIntent != null)
{
waIntent.setType("text/plain");
String text = Title;
waIntent.setPackage("com.whatsapp");
waIntent.putExtra(Intent.EXTRA_TEXT, text);//
mContext.startActivity(Intent.createChooser(waIntent,
"مشاركة بواسطة..."));
}
}
});
}
return convertView;
}
}
非常感谢您的帮助！