我有一个列表视图，其中包含三个不同自定义行的大量通货膨胀。从这些行我必须收集数据并填充数据库并最终获得该数据。现在问题是创建的行数取决于用户它可能高达100。我的列表在滚动时变得非常慢。现在我想知道的是将我的所有列表功能放在异步任务中是有帮助的，这意味着它的创建和执行。下面是我的代码片段。
private class Async extends AsyncTask<String, Integer, String>{
@Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
runOnUiThread(new Runnable() {
public void run() {
lv.setAdapter(new EfficientAdapterAB(Measure_New.this));
new EfficientAdapterAB(Measure_New.this).notifyDataSetChanged();
//stuff that updates ui
}
});
return null;
}
}
private class EfficientAdapterAB extends BaseAdapter {
private LayoutInflater mInflater;
View[] view;
ViewHolderAB holderAB;
/* RadioButton[] ob=new RadioButton[n];
RadioButton[] ra=new RadioButton[n];*/
AndroidOpenDbHelper androidOpenDbHelperObj = new AndroidOpenDbHelper(Measure_New.this);
SQLiteDatabase sqliteDatabase = androidOpenDbHelperObj.getReadableDatabase();
String q="SELECT * FROM ab_measurement WHERE job_id=" +"\""+Settings.jobid +"\"";
Cursor cursor = sqliteDatabase.rawQuery(q,null);
public EfficientAdapterAB(Context context) {
mInflater = LayoutInflater.from(context);
}
public int getCount() {
System.out.println("in getcount value of n is "+n);
view = new View[n+2];
return n+2;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(final int position, View convertView, ViewGroup parent) {
final RadioButton[] ob=new RadioButton[n];
final RadioButton[] ra=new RadioButton[n];
holderAB = new ViewHolderAB();
final EditText edit_a_ft,edit_a_inch,edit_b_ft,edit_b_inch,edit_ab_a_ft,edit_ab_a_inch,edit_ab_b_ft,edit_ab_b_inch;
if (view[position] == null) {
if(position==0){
convertView = mInflater.inflate(R.layout.measure_upper_bar, null);
txt_ft_mtr=(TextView)convertView.findViewById(R.id.textView_ft_mtr);
txt_inch_cm=(TextView)convertView.findViewById(R.id.textView_inch_cm);
if(Settings.metric_count==1){
txt_ft_mtr.setText(""+"Meter");
txt_inch_cm.setText(""+"Centimeter");
}
user_input= (EditText) convertView.findViewById(R.id.Num_edittxt_measure_new);
gettingUserInput();
new EfficientAdapterAB(Measure_New.this).notifyDataSetChanged();
System.out.println("after gettinguserInput value of n is "+n);
feet=(EditText)convertView.findViewById(R.id.Feet_edittxt);
inch =(EditText)convertView.findViewById(R.id.Inches_Edittxt);
feet.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
try{
val_feet_baseline=Integer.parseInt(feet.getText().toString());
}catch (Exception e) {
// TODO: handle exception
}
}
});
inch.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
try{
val_inch_baseline=Integer.parseInt(inch.getText().toString());
if(val_inch_baseline>=ft_mtr){
inch_greater=true;
ft_baseline=val_feet_baseline+(val_inch_baseline/ft_mtr);
val_inch_baseline=val_inch_baseline%ft_mtr;
feet.setText(""+ft_baseline);
inch.setText(""+val_inch_baseline);
System.out.println("yes its working values of feet and inch is "+"feet"+ft_baseline+"inch"+val_inch_baseline);
}
}
catch (Exception e) {
// TODO: handle exception
}
}
});
if(inch_greater==true){
baseline_length=String.valueOf(ft_baseline).concat(".").concat(String.valueOf(val_inch_baseline));
feet.setText(""+ft_baseline);
System.out.println("in the if part");
inch_greater=false;
}
else{
baseline_length=String.valueOf(val_feet_baseline).concat(".").concat(String.valueOf(val_inch_baseline));
System.out.println("in the else part");
feet.setText(""+val_feet_baseline);
}
inch.setText(""+val_inch_baseline);
if(val_feet_baseline==0){
feet.setText(""+"");
}
if(val_inch_baseline==0){
inch.setText(""+"");
}
user_input.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
user_input.setText("");
InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
imm.showSoftInput(user_input, InputMethodManager.SHOW_IMPLICIT);
((InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE)).toggleSoftInput(InputMethodManager.SHOW_FORCED, InputMethodManager.HIDE_IMPLICIT_ONLY);
}
});
rb_A = (RadioButton)convertView.findViewById(R.id.radio_A);
rb_B = (RadioButton)convertView.findViewById(R.id.radio_B);
rb_AB = (RadioButton)convertView.findViewById(R.id.radio_A_B);
rb_A.setOnClickListener(Measure_New.this);
rb_B.setOnClickListener(Measure_New.this);
rb_AB.setOnClickListener(Measure_New.this);
view[position] = convertView;
}
else if(position==n+1){
convertView=mInflater.inflate( R.layout.details_continue_btn, null);
convertView.findViewById(R.id.btn_Continue).setOnClickListener(Measure_New.this);
convertView.findViewById(R.id.btn_exit_restart).setOnClickListener(Measure_New.this);
view[position] = convertView;
}
else{
if(optn_checkd==1){
setDatabase();
convertView = mInflater.inflate(R.layout.a_xml, null);
txt_A_ft_mtr=(TextView)convertView.findViewById(R.id.textView_A_ft_mtr);
txt_A_inch_cm=(TextView)convertView.findViewById(R.id.TextView_A_inch_cm);
if(Settings.metric_count ==1){
txt_A_ft_mtr.setText(""+"A(m.)");
txt_A_inch_cm.setText(""+"A(cm.)");
}
holderAB.text = (TextView) convertView.findViewById(R.id.num_txt);
holderAB.text.setText(""+(position));
edit_a_ft=(EditText) convertView.findViewById(R.id.editText_A_ft);
edit_a_inch=(EditText) convertView.findViewById(R.id.editText_A_inch);
if(position<=n){
textChangeListenerForFeet(edit_a_ft,position,al_edit_A_ft);
textChangeListenerForInch(edit_a_inch,edit_a_ft,position,al_edit_A_inch);
}
System.out.println("in else value of position before crashing is"+position+" "+(position-1)+" "+ n);
if(position<=n){
ob[position-1]=(RadioButton)convertView.findViewById(R.id.radio_Obstruction_a);
ob[position-1].setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(radio__ob_flag[position-1]==true){
ob[position-1].setButtonDrawable(R.drawable.redioon);
obstruction/*[position-1]*/="Y";
radio__ob_flag[position-1]=false;
}
else{
ob[position-1].setButtonDrawable(R.drawable.rediooff);
radio__ob_flag[position-1]=true;
obstruction/*[position-1]*/="N";
}
try{
al_ob_a.add(position-1,obstruction/*[position-1]*/);
al_ob_a.remove(position);
}catch(Exception e){
}
System.out.println("wooooow here i am ob"+al_ob_a);
}
});
}
if(position<=n){
ra[position-1]=(RadioButton)convertView.findViewById(R.id.radio_Raisedwall_a);
ra[position-1].setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(radio__ra_flag[position-1]==true){
ra[position-1].setButtonDrawable(R.drawable.redioon);
radio__ra_flag[position-1]=false;
obstruction/*[position-1]*/="Y";
}
else{
ra[position-1].setButtonDrawable(R.drawable.rediooff);
radio__ra_flag[position-1]=true;
obstruction/*[position-1]*/="N";
}
try{
al_ra_a.add(position-1,obstruction/*[position-1]*/);
al_ra_a.remove(position);
}catch(Exception e){
}
System.out.println("wooooow here i am ra "+al_ra_a);
}
});
}
if(getttingFromDbForMeasure()==true){
if(position<=n){
retainingInput(al_edit_A_ft,position,edit_a_ft);
retainingInput(al_edit_A_inch,position,edit_a_inch);
retainingInputForRadio( al_ob_a,position,ob);
retainingInputForRadio(al_ra_a ,position,ra);
}
}
}
答案 0 :(得分：0)
首先，您需要在Yours适配器getView（）中使用convertView。这将允许您使用视图持有者。目前您只为viewHolder分配值，但不将其设置为标记或检索值（以避免冗余的findViewById调用）。
结帐this Google I/O video from Romain Guy以及该会话的结帐the code幻灯片。