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I am very new to Android app development. I created my own list adapter, as shown below, and I want this list to be validated. What do I need to do so that there is a check box for each line in my list?

public class listAvtivity extends ListActivity { private LayoutInflater mInflater; private Vector<RowData> data; RowData rd; static final String[] title = new String[] { "*New*Apple iPad Wi-Fi (16GB)", "7 Touch Tablet -2GB Google Android", "Apple iPad Wi-Fi (16GB) Rarely Used ","Apple iPad Wi-Fi (16GB) AppleCase" }; static final String[] detail = new String[] { "1h 37m Shipping: $10.00","1h 39m Shipping: Free","58m 6s Shipping:$10.00","59m 30s Shipping: $10.95" }; //private Integer[] imgid = { // R.drawable.bsfimg,R.drawable.bsfimg4,R.drawable.bsfimg2, // R.drawable.bsfimg5 //}; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mInflater = (LayoutInflater) getSystemService( Activity.LAYOUT_INFLATER_SERVICE); data = new Vector<RowData>(); for(int i=0;i<title.length;i++){ try { rd = new RowData(i,title[i],detail[i]); } catch (ParseException e) { e.printStackTrace(); } data.add(rd); } CustomAdapter adapter = new CustomAdapter(this, R.layout.list, R.id.title, data); setListAdapter(adapter); getListView().setTextFilterEnabled(true); } public void onListItemClick(ListView parent, View v, int position, long id) { Toast.makeText(getApplicationContext(), "You have selected " +(position+1)+"th item", Toast.LENGTH_SHORT).show(); } private class RowData { protected int mId; protected String mTitle; protected String mDetail; RowData(int id,String title,String detail){ mId=id; mTitle = title; mDetail=detail; } @Override public String toString() { return mId+" "+mTitle+" "+mDetail; } } private class CustomAdapter extends ArrayAdapter<RowData> { public CustomAdapter(Context context, int resource, int textViewResourceId, List<RowData> objects) { super(context, resource, textViewResourceId, objects); } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder = null; TextView title = null; TextView detail = null; //ImageView i11=null; RowData rowData= getItem(position); if(null == convertView){ convertView = mInflater.inflate(R.layout.list, null); holder = new ViewHolder(convertView); convertView.setTag(holder); } holder = (ViewHolder) convertView.getTag(); title = holder.gettitle(); itle.setText(rowData.mTitle); detail = holder.getdetail(); detail.setText(rowData.mDetail); //i11=holder.getImage(); //i11.setImageResource(imgid[rowData.mId]); return convertView; } private class ViewHolder { private View mRow; private TextView title = null; private TextView detail = null; //private ImageView i11=null; public ViewHolder(View row) { mRow = row; } public TextView gettitle() { if(null == title){ title = (TextView) mRow.findViewById(R.id.title); } return title; } public TextView getdetail() { if(null == detail){ detail = (TextView) mRow.findViewById(R.id.detail); } return detail; } //public ImageView getImage() { // if(null == i11){ // i11 = (ImageView) mRow.findViewById(R.id.img); // } //return i11; //} } } }
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2 answers

I liked the decision of Carlos Sessa from his book “50 Android hacks”.

my activity_favorites.xml is as follows:

 <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent"> <ListView android:id="@+id/favContainer" android:layout_width="fill_parent" android:layout_height="fill_parent" android:choiceMode="singleChoice"/> </RelativeLayout>

My FavoritesActivity.java looks like this:

 package com.myproject; import java.util.ArrayList; import com.myproject.R; import com.myproject.model.Package; import com.myproject.adapter.FavoritesPackageArrayAdapter; import com.myproject.utils.DatabaseHelper; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.Menu; import android.view.View; import android.view.Window; import android.widget.ListView; public class FavoritesActivity extends Activity { protected ListView list; protected String selectedPackage; protected ArrayList<Package> packages; protected FavoritesPackageArrayAdapter adapter; private DatabaseHelper db = new DatabaseHelper(this); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.activity_favorites); packages = db.getPackages(); adapter = new FavoritesPackageArrayAdapter(this, -1, packages); list = (ListView) findViewById(R.id.favContainer); list.setAdapter(adapter); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main, menu); return true; } public void onSelect(View view) { int pos = list.getCheckedItemPosition(); if(ListView.INVALID_POSITION != pos) selectedPackage = packages.get(pos).getId(); } }

My ListView adapter (FavoritesPackageArrayAdapter.java) is pretty simple:

 package com.myproject.adapter; import java.util.List; import com.myproject.model.Package; import com.myproject.view.PackageView; import android.content.Context; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; public class FavoritesPackageArrayAdapter extends ArrayAdapter<Package> { public FavoritesPackageArrayAdapter(Context context, int resource, List<Package> objects) { super(context, resource, objects); } @Override public View getView(int position, View convertView, ViewGroup parent) { if(convertView == null) convertView = new PackageView(getContext()); Package pack = getItem(position); PackageView packView = (PackageView) convertView; packView.setPackage(pack); return convertView; } }

To check list items, your view must implement the Checkable interface. My PackageView.java looks like this:

 package com.myproject.view; import java.util.ArrayList; import com.myproject.R; import com.myproject.model.Package; import com.myproject.model.PackageEvent; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.widget.Checkable; import android.widget.LinearLayout; import android.widget.TextView; import android.widget.CheckBox; public class PackageView extends LinearLayout implements Checkable { private View v; private TextView tv0; private TextView tv1; private TextView tv2; private TextView tv3; private CheckBox testCheckBox; public PackageView(Context context) { super(context); LayoutInflater inflater = LayoutInflater.from(context); v = inflater.inflate(R.layout.favorites_package, this, true); tv0 = (TextView) v.findViewById(R.id.favPackageId); tv1 = (TextView) v.findViewById(R.id.favEventDate); tv2 = (TextView) v.findViewById(R.id.favEventAddres); tv3 = (TextView) v.findViewById(R.id.favEventState); // I don't have checkbox in my layout, but if I had: // testCheckBox = (CheckBox) v.findViewById(R.id.checkBoxId); } public void setPackage(Package pack) { // my custom method where I set package id, date, and time ... } private Boolean checked = false; @Override public boolean isChecked() { return checked; // if I had checkbox in my layout I could // return testCheckBox.checked(); } @Override public void setChecked(boolean checked) { this.checked = checked; // since I choose not to have check box in my layout, I change background color // according to checked state if(isChecked()) ... else ... // if I had checkbox in my layout I could // testCheckBox.setChecked(checked); } @Override public void toggle() { checked = !checked; // if I had checkbox in my layout I could // return testCheckBox.toggle(); } }

And finally, the xml layout of each list item (favorites_package.xml):

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="vertical"> <TextView android:id="@+id/favPackageId" android:layout_width="match_parent" android:layout_height="wrap_content"/> <LinearLayout android:id="@+id/favTimeDateContainer" android:layout_width="match_parent" android:layout_height="wrap_content" android:weightSum="1"> <TextView android:id="@+id/favEventDate" android:layout_width="0dp" android:layout_height="match_parent" android:layout_weight="0.5"/> <TextView android:id="@+id/favEventAddres" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="0.5"/> </LinearLayout> <TextView android:id="@+id/favEventState" android:layout_width="match_parent" android:layout_height="wrap_content"/> </LinearLayout>

If you want to have the actual flag in your layout, then the xml should look something like this:

 <CheckBox android:id="@+id/checkBoxId" android:layout_width="wrap_content" android:layout_height="wrap_content" android:clickable="false" android:focusable="false" android:focusableInTouchMode="false"/>

If you leave the checkbox interactively, you can check it only by clicking on the checkbox. Also, do not make your layout clickable, for some reason it does not work with the Checkable interface.

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Take a look at this sample code.

http://www.androidpeople.com/android-listview-multiple-choice-example

--- Change -

You have not posted your xml files. To create a custom list string, I did it this way. First I setcontentview which contains my list in your java code.

 setContentView(R.layout.list_main);

Then your list_main.xml file should contain listview

 <ListView android:id="@android:id/list" android:layout_width="fill_parent" android:layout_height="wrap_content" />

AFterwards Data Transfer Adapter

  setListAdapter(new YOUR_ADAPTER_CLASS(this, R.layout.list_item, YOUR_OBJECT));

To get a custom list item, create a list_item.xml file that contains your custom string. You can place line outputs, images or flags here.

Then get a list of views

  ListView listView = getListView();

You can install the onitemclick listener here

 listView.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { //YOUR_CODE_HERE } });

Then in your custom adapter file you can implement the getview function

 @Override public View getView(int position, View convertView, ViewGroup parent) { View view = convertView; if (view == null) { LayoutInflater layoutInflator = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = layoutInflator.inflate(R.layout.list_item, null); } //YOU CAN GET EVERY OBJECT AND SET YOUR CUSTOM ROW like below //view.findViewById(R.id.YOUR_OBJECT_ID_HERE); return view; }

I could not look at your code and say what was wrong, but this is the right way to implement custom strings for listview in android.

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Source: https://habr.com/ru/post/887635/

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