Android 共享首选项：检索并显示存储的数据
我已利用共享首选项将数据存储到MyUserChoice.xml中：Android 共享首选项：检索并显示存储的数据,android,sharedpreferences,Android,Sharedpreferences,我已利用共享首选项将数据存储到MyUserChoice.xml中： <string name="MyUserChoice">ApplicationInfo{1ebad2cb com.example.user.example}, ApplicationInfo{15c7caa8 com.android.gallery}, ApplicationInfo{bc0a9c1 com.android.quicksearchbox}</string> 相反，它不返回
<string name="MyUserChoice">ApplicationInfo{1ebad2cb com.example.user.example},
ApplicationInfo{15c7caa8 com.android.gallery},
ApplicationInfo{bc0a9c1 com.android.quicksearchbox}</string>
10-09 01:19:18.756 1311-1311/com.android.systemui W/ResourceType﹕ No package identifier when getting value for resource number 0x00000000
10-09 01:19:18.756 1311-1311/com.android.systemui W/PackageManager﹕ Failure retrieving resources for com.example.checkboxsharedpreferences: Resource ID #0x0
10-09 01:19:18.781 1311-1327/com.android.systemui I/art﹕ Background sticky concurrent mark sweep GC freed 10643(410KB) AllocSpace objects, 0(0B) LOS objects, 0% free, 22MB/22MB, paused 5.699ms total 16.577ms
10-09 01:19:19.371 931-931/? W/SurfaceFlinger﹕ couldn't log to binary event log: overflow.
ListView myList;
Button getChoice, clearAll, selectAll;
SharedPreferences sharedpreferences;
public static final String MyPREFERENCES = "MyUserChoice" ;
ArrayList<String> selectedItems = new ArrayList<String>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myList = (ListView)findViewById(android.R.id.list);
getChoice = (Button)findViewById(R.id.getchoice);
clearAll = (Button)findViewById(R.id.clearall);
selectAll = (Button)findViewById(R.id.selectall);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_multiple_choice);
myList.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
myList.setAdapter(adapter);
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
if(sharedpreferences.contains(MyPREFERENCES)){
LoadSelections();
}
getChoice.setOnClickListener(new Button.OnClickListener() {
@Override
public void onClick(View v) {
String selected = "";
int cntChoice = myList.getCount();
SparseBooleanArray sparseBooleanArray = myList.getCheckedItemPositions();
for (int i = 0; i < cntChoice; i++) {
if (sparseBooleanArray.get(i)) {
selected += myList.getItemAtPosition(i).toString() + "\n";
System.out.println("Checking list while adding:" + myList.getItemAtPosition(i).toString());
SaveSelections();
}
}
Toast.makeText(MainActivity.this, selected, Toast.LENGTH_LONG).show();
}
});
clearAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ClearSelections();
}
});
selectAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
SelectAllSelections();
}
});
packageManager = getPackageManager();
new LoadApplications().execute();
}
private void SaveSelections() {
// save the selections in the shared preference in private mode for the user
SharedPreferences.Editor prefEditor = sharedpreferences.edit();
String savedItems = getSavedItems();
prefEditor.putString(MyPREFERENCES.toString(), savedItems);
prefEditor.commit();
}
private String getSavedItems() {
String savedItems = "";
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
if (this.myList.isItemChecked(i)) {
if (savedItems.length() > 0) {
savedItems += "," + this.myList.getItemAtPosition(i);
} else {
savedItems += this.myList.getItemAtPosition(i);
}
}
}
return savedItems;
}
private void LoadSelections() {
// if the selections were previously saved load them
if (sharedpreferences.contains(MyPREFERENCES.toString())) {
String savedItems = sharedpreferences.getString(MyPREFERENCES.toString(), "");
selectedItems.addAll(Arrays.asList(savedItems.split(",")));
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
String currentItem = (String) myList.getAdapter()
.getItem(i);
if (selectedItems.contains(currentItem)) {
myList.setItemChecked(i, true);
Toast.makeText(getApplicationContext(),
"Current Item: " + currentItem,
Toast.LENGTH_LONG).show();
} else {
myList.setItemChecked(i, false);
}
}
}
}
private void ClearSelections() {
// user has clicked clear button so uncheck all the items
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
this.myList.setItemChecked(i, false);
}
// also clear the saved selections
SaveSelections();
}
private void SelectAllSelections() {
// user has clicked clear button so uncheck all the items
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
this.myList.setItemChecked(i, true);
}
// also clear the saved selections then uncomment the below line.
// SaveSelections();
}
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(intent != null){
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(packageManager.getLaunchIntentForPackage(info.packageName)!=null){
appList.add(info);
}
}catch(Exception e){
e.printStackTrace();
}
}
return appList;
}
private class LoadApplications extends AsyncTask<Void, Void, Void>{
private ProgressDialog progress = null;
protected Void doInBackground(Void... params){
applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA));
listadapter = new AppAdapter(MainActivity.this, R.layout.activity_list_app, applist);
return null;
}
protected void onPostExecute(Void result){
setListAdapter(listadapter);
progress.dismiss();
super.onPostExecute(result);
}
protected void onPreExecute(){
progress = ProgressDialog.show(MainActivity.this, null, "Loading apps info...");
super.onPreExecute();
}
}
}
ListView-myList；
按钮getChoice、clearAll、selectAll；
SharedReferences SharedReferences；
公共静态最终字符串MyPREFERENCES=“MyUserChoice”；
ArrayList selectedItems=新建ArrayList（）；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity_main）；
myList=（ListView）findViewById（android.R.id.list）；
getChoice=（按钮）findViewById（R.id.getChoice）；
clearAll=（按钮）findViewById（R.id.clearAll）；
selectAll=（按钮）findViewById（R.id.selectAll）；
ArrayAdapter=新的ArrayAdapter（这是android.R.layout.simple\u list\u item\u多选）；
myList.setChoiceMode（ListView.CHOICE\u MODE\u MULTIPLE）；
myList.setAdapter（适配器）；
SharedReferences=GetSharedReferences（MyPREFERENCES，Context.MODE\u PRIVATE）；
if（SharedReferences.contains（MyPREFERENCES））{
LoadSelections（）；
}
getChoice.setOnClickListener（新建按钮.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
所选字符串=”；
int cntChoice=myList.getCount（）；
SparseBooleanArray SparseBooleanArray=myList.getCheckedItemPositions（）；
for（int i=0；i0）{
savedItems+=“，”+this.myList.getItemAtPosition（i）；
}否则{
savedItems+=this.myList.getItemAtPosition（i）；
}
}
}
返回savedItems；
}
私有void LoadSelections（）{
//如果以前保存了选择，请加载它们
if（SharedReferences.contains（MyPREFERENCES.toString（）））{
String savedItems=SharedReferences.getString（MyPREFERENCES.toString（），“”）；
选择editems.addAll（Arrays.asList（savedItems.split（“，”））；
int count=this.myList.getAdapter（）.getCount（）；
for（int i=0；i10-09 01:19:18.756 1311-1311/com.android.systemui W/ResourceType﹕ No package identifier when getting value for resource number 0x00000000
10-09 01:19:18.756 1311-1311/com.android.systemui W/PackageManager﹕ Failure retrieving resources for com.example.checkboxsharedpreferences: Resource ID #0x0
10-09 01:19:18.781 1311-1327/com.android.systemui I/art﹕ Background sticky concurrent mark sweep GC freed 10643(410KB) AllocSpace objects, 0(0B) LOS objects, 0% free, 22MB/22MB, paused 5.699ms total 16.577ms
10-09 01:19:19.371 931-931/? W/SurfaceFlinger﹕ couldn't log to binary event log: overflow.
ListView myList;
Button getChoice, clearAll, selectAll;
SharedPreferences sharedpreferences;
public static final String MyPREFERENCES = "MyUserChoice" ;
ArrayList<String> selectedItems = new ArrayList<String>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myList = (ListView)findViewById(android.R.id.list);
getChoice = (Button)findViewById(R.id.getchoice);
clearAll = (Button)findViewById(R.id.clearall);
selectAll = (Button)findViewById(R.id.selectall);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_multiple_choice);
myList.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
myList.setAdapter(adapter);
sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
if(sharedpreferences.contains(MyPREFERENCES)){
LoadSelections();
}
getChoice.setOnClickListener(new Button.OnClickListener() {
@Override
public void onClick(View v) {
String selected = "";
int cntChoice = myList.getCount();
SparseBooleanArray sparseBooleanArray = myList.getCheckedItemPositions();
for (int i = 0; i < cntChoice; i++) {
if (sparseBooleanArray.get(i)) {
selected += myList.getItemAtPosition(i).toString() + "\n";
System.out.println("Checking list while adding:" + myList.getItemAtPosition(i).toString());
SaveSelections();
}
}
Toast.makeText(MainActivity.this, selected, Toast.LENGTH_LONG).show();
}
});
clearAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
ClearSelections();
}
});
selectAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
SelectAllSelections();
}
});
packageManager = getPackageManager();
new LoadApplications().execute();
}
private void SaveSelections() {
// save the selections in the shared preference in private mode for the user
SharedPreferences.Editor prefEditor = sharedpreferences.edit();
String savedItems = getSavedItems();
prefEditor.putString(MyPREFERENCES.toString(), savedItems);
prefEditor.commit();
}
private String getSavedItems() {
String savedItems = "";
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
if (this.myList.isItemChecked(i)) {
if (savedItems.length() > 0) {
savedItems += "," + this.myList.getItemAtPosition(i);
} else {
savedItems += this.myList.getItemAtPosition(i);
}
}
}
return savedItems;
}
private void LoadSelections() {
// if the selections were previously saved load them
if (sharedpreferences.contains(MyPREFERENCES.toString())) {
String savedItems = sharedpreferences.getString(MyPREFERENCES.toString(), "");
selectedItems.addAll(Arrays.asList(savedItems.split(",")));
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
String currentItem = (String) myList.getAdapter()
.getItem(i);
if (selectedItems.contains(currentItem)) {
myList.setItemChecked(i, true);
Toast.makeText(getApplicationContext(),
"Current Item: " + currentItem,
Toast.LENGTH_LONG).show();
} else {
myList.setItemChecked(i, false);
}
}
}
}
private void ClearSelections() {
// user has clicked clear button so uncheck all the items
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
this.myList.setItemChecked(i, false);
}
// also clear the saved selections
SaveSelections();
}
private void SelectAllSelections() {
// user has clicked clear button so uncheck all the items
int count = this.myList.getAdapter().getCount();
for (int i = 0; i < count; i++) {
this.myList.setItemChecked(i, true);
}
// also clear the saved selections then uncomment the below line.
// SaveSelections();
}
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(intent != null){
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(packageManager.getLaunchIntentForPackage(info.packageName)!=null){
appList.add(info);
}
}catch(Exception e){
e.printStackTrace();
}
}
return appList;
}
private class LoadApplications extends AsyncTask<Void, Void, Void>{
private ProgressDialog progress = null;
protected Void doInBackground(Void... params){
applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA));
listadapter = new AppAdapter(MainActivity.this, R.layout.activity_list_app, applist);
return null;
}
protected void onPostExecute(Void result){
setListAdapter(listadapter);
progress.dismiss();
super.onPostExecute(result);
}
protected void onPreExecute(){
progress = ProgressDialog.show(MainActivity.this, null, "Loading apps info...");
super.onPreExecute();
}
}
}
SharedPreferences.Editor prefEditor = sharedpreferences.edit();
String savedItems = getSavedItems();
prefEditor.putString(MyPREFERENCES, savedItems);
prefEditor.commit();
SharedPreferences sharedpreferences= getSharedPreferences(PREF_NAME, MODE_PRIVATE);
String channel = sharedpreferences.getString(MyPREFERENCES, "null");
sharedpreferences.contains(MyPREFERENCES.toString())
!sharedpreferences.getString(MyPREFERENCES, "").equals("")