Chethan Shetty Chethan Shetty - 1 month ago 20
Android Question

How to list all installed applications with icon and check box in android

Hi

stackoverflow
I'm trying to develop an application which can display a list of all
installed application
with their
Icon, Name & Check Box
, here follows my code

activity_main.xml


<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

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

</LinearLayout>


row.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="horizontal" >

<ImageView
android:id="@+id/app_icon"
android:layout_width="50dp"
android:layout_height="50dp"
android:padding="3dp"
android:scaleType="centerCrop" />

<LinearLayout
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:gravity="center_vertical"
android:orientation="vertical"
android:paddingLeft="5dp" >

<TextView
android:id="@+id/app_name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:textStyle="bold" />

<TextView
android:id="@+id/app_paackage"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical" />
</LinearLayout>

<CheckBox
android:id="@+id/cb_app"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

</LinearLayout>


MainActivity.java


public class MainActivity extends ListActivity {
private PackageManager packageManager = null;
private List<ApplicationInfo> applist = null;
private ApplicationAdapter listadaptor = null;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

packageManager = getPackageManager();

new LoadApplications().execute();
}

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);

ApplicationInfo app = applist.get(position);
try {
Intent intent = packageManager
.getLaunchIntentForPackage(app.packageName);

if (null != intent) {
startActivity(intent);
}
} catch (ActivityNotFoundException e) {
Toast.makeText(MainActivity.this, e.getMessage(),
Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(MainActivity.this, e.getMessage(),
Toast.LENGTH_LONG).show();
}
}

private List<ApplicationInfo> checkForLaunchIntent(List<ApplicationInfo> list) {
ArrayList<ApplicationInfo> applist = new ArrayList<ApplicationInfo>();
for (ApplicationInfo info : list) {
try {
if (null != packageManager.getLaunchIntentForPackage(info.packageName)) {
applist.add(info);
}
} catch (Exception e) {
e.printStackTrace();
}
}

return applist;
}

private class LoadApplications extends AsyncTask<Void, Void, Void> {
private ProgressDialog progress = null;

@Override
protected Void doInBackground(Void... params) {
applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA));
listadaptor = new ApplicationAdapter(MainActivity.this,
R.layout.row, applist);

return null;
}

@Override
protected void onCancelled() {
super.onCancelled();
}

@Override
protected void onPostExecute(Void result) {
setListAdapter(listadaptor);
progress.dismiss();
super.onPostExecute(result);
}

@Override
protected void onPreExecute() {
progress = ProgressDialog.show(MainActivity.this, null,
"Loading application info...");
super.onPreExecute();
}

@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
}
}


ApplicationAdapter.java


import java.util.List;

import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class ApplicationAdapter extends ArrayAdapter<ApplicationInfo> {
private List<ApplicationInfo> appsList = null;
private Context context;
private PackageManager packageManager;

public ApplicationAdapter(Context context, int textViewResourceId,
List<ApplicationInfo> appsList) {
super(context, textViewResourceId, appsList);
this.context = context;
this.appsList = appsList;
packageManager = context.getPackageManager();
}

@Override
public int getCount() {
return ((null != appsList) ? appsList.size() : 0);
}

@Override
public ApplicationInfo getItem(int position) {
return ((null != appsList) ? appsList.get(position) : null);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
if (null == view) {
LayoutInflater layoutInflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = layoutInflater.inflate(R.layout.row, null);
}

ApplicationInfo data = appsList.get(position);
if (null != data) {
TextView appName = (TextView) view.findViewById(R.id.app_name);
TextView packageName = (TextView) view.findViewById(R.id.app_paackage);
ImageView iconview = (ImageView) view.findViewById(R.id.app_icon);

appName.setText(data.loadLabel(packageManager));
packageName.setText(data.packageName);
iconview.setImageDrawable(data.loadIcon(packageManager));
}
return view;
}


Problem is whenever I tick a
Check Box
and scroll other boxes in the scrolled window
Check Box
are being
selected
. Please help me to solve this riddle.

Thanks.

Answer

The reason why this happens is because your views are being re-used but you do not reset the state of the checkbox in the getView.

I suggest you do something like this:

import java.util.List;

import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class ApplicationAdapter extends ArrayAdapter<ApplicationInfo> {
private List<ApplicationInfo> appsList = null;
private Context context;
private PackageManager packageManager;
private ArrayList<Boolean> checkList = new ArrayList<Boolean>();

public ApplicationAdapter(Context context, int textViewResourceId,
        List<ApplicationInfo> appsList) {
    super(context, textViewResourceId, appsList);
    this.context = context;
    this.appsList = appsList;
    packageManager = context.getPackageManager();

    for (int i = 0; i < appsList.size(); i++) {
        checkList.add(false);
    }
}

@Override
public int getCount() {
    return ((null != appsList) ? appsList.size() : 0);
}

@Override
public ApplicationInfo getItem(int position) {
    return ((null != appsList) ? appsList.get(position) : null);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View view = convertView;
    if (null == view) {
        LayoutInflater layoutInflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = layoutInflater.inflate(R.layout.row, null);
    }

    ApplicationInfo data = appsList.get(position);
    if (null != data) {
        TextView appName = (TextView) view.findViewById(R.id.app_name);
        TextView packageName = (TextView) view.findViewById(R.id.app_paackage);
        ImageView iconview = (ImageView) view.findViewById(R.id.app_icon);

        CheckBox checkBox = (CheckBox) view.findViewById(R.id.cb_app);
        checkBox.setTag(Integer.valueOf(position)); // set the tag so we can identify the correct row in the listener
        checkBox.setChecked(checkList.get(position); // set the status as we stored it        
        checkBox.setOnCheckedChangeListener(mListener); // set the listener

        appName.setText(data.loadLabel(packageManager));
        packageName.setText(data.packageName);
        iconview.setImageDrawable(data.loadIcon(packageManager));
    }
    return view;
}

OnCheckedChangeListener mListener = new OnCheckedChangeListener() {

     public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {   
         checkList.set((Integer)buttonView.getTag(),isChecked); // get the tag so we know the row and store the status 
     }
};
}

Basically, have a arraylist which stores the status of each checkbox (that corresponds to your data). So for example: When you checkbox at position 1 is clicked, checkList.get(1) is true.

Since views are being re-used you need to store the state of each checkbox with respect to its position. i.e checkbox at position x is checked or not. Then when you do getView() for position x you use the stored state to set the correct checked value.

Update Initialize the checkList with false values.