I have written code that displays list of installed apps along with checkbox. However, when I close the app, checkbox value resets. I learned that by using Shared Preference I can save state of checkbox. However I am not able to implement it in my project. I am very new to this. So, I request to provide detailed solution. Also, I have one more question.In this code, state of checkbox is saved in array named checklist. Instead is it possible to create boolean variables that has name equal to App name ( which we get from PackageManager) and value will be status of checkbox. for instance boolean Browser or Boolean Camera. The code is posted below. Thanks in advance!!
MainActivity.java
public class MainActivity extends ListActivity {
private PackageManager packageManager = null;
private List<ApplicationInfo> applist = null;
private ApplicationAdapter listadapter = 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));
listadapter = new ApplicationAdapter(MainActivity.this,
R.layout.row, applist);
return null;
}
@Override
protected void onCancelled() {
super.onCancelled();
}
@Override
protected void onPostExecute(Void result) {
setListAdapter(listadapter);
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
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_package);
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;
}
CompoundButton.OnCheckedChangeListener mListener = new CompoundButton.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
}
};
}
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</ListView>
</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:scaleType="centerCrop"
android:padding="3dp"
android:src="@drawable/download" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="vertical"
android:paddingLeft="5dp" >
<TextView
android:id="@+id/app_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:textStyle="bold" />
<TextView
android:id="@+id/app_package"
android:layout_width="wrap_content"
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>
EDIT: As per @Falco Winkler suggestion, I modified my custom adapter as below.
ApplicationAdapter.java
import android.content.Context;
import android.content.SharedPreferences;
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.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
public class ApplicationAdapter extends ArrayAdapter<ApplicationInfo> {
private List<ApplicationInfo> appsList = null;
private Context context;
private PackageManager packageManager;
private SharedPreferences prefs;
public ApplicationAdapter(Context context, int textViewResourceId,
List<ApplicationInfo> appsList) {
super(context, textViewResourceId, appsList);
this.context = context;
this.appsList = appsList;
packageManager = context.getPackageManager();
prefs = context.getSharedPreferences("checkboxstate",Context.MODE_PRIVATE);
}
@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_package);
ImageView iconview = (ImageView) view.findViewById(R.id.app_icon);
CheckBox checkBox = (CheckBox) view.findViewById(R.id.cb_app);
checkBox.setTag(String.valueOf(appName)); // set the tag so we can identify the correct row in the listener
checkBox.setChecked(prefs.getBoolean(checkBox.getTag().toString(), false)); // set the status as we stored it
checkBox.setOnClickListener(onclicklistener);
appName.setText(data.loadLabel(packageManager));
packageName.setText(data.packageName);
iconview.setImageDrawable(data.loadIcon(packageManager));
}
return view;
}
CheckBox.OnClickListener onclicklistener = new View.OnClickListener() {
@Override
public void onClick(View v) {
prefs.edit().putBoolean(v.getTag().toString(),((CheckBox)v).isChecked()).apply();
}
};
}
However, the value of checkboxes is still not saved and everything resets after I close the application. What am I missing ?
EDIT1: As per new suggestion, I have modified my Custom adapter. However, even though i see some checkboxes already checked, it is random. For instance, if i check 3rd checkbox and reopen App, 2nd checkbox will be checked instead of 3rd.. Also, some other checkboxes are selected randomly. I am posting modified code below.
package com.example.monika.savenotification;
import android.content.Context;
import android.content.SharedPreferences;
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.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
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);
}
final ApplicationInfo data = appsList.get(position);
final SharedPreferences prefs = context.getSharedPreferences("checkboxstate", Context.MODE_PRIVATE);
if (null != data) {
TextView appName = (TextView) view.findViewById(R.id.app_name);
TextView packageName = (TextView) view.findViewById(R.id.app_package);
ImageView iconview = (ImageView) view.findViewById(R.id.app_icon);
CheckBox checkBox = (CheckBox) view.findViewById(R.id.cb_app);
checkBox.setTag(data); // set the tag so we can identify the correct row in the listener
checkBox.setChecked(prefs.getBoolean(data.packageName, false)); // set the status as we stored it
checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
prefs.edit().putBoolean(data.packageName, isChecked).apply();
}
});
appName.setText(data.loadLabel(packageManager));
packageName.setText(data.packageName);
iconview.setImageDrawable(data.loadIcon(packageManager));
}
return view;
}
}
What modifications do I need to do further ? Thanks in advance..
