Я думаю, что следующий код поможет ....
public void btnShareClick(View v) {
// shareBtnFlag = 1;
Dialog d = new Dialog(DrawAppActivity.this);
d.requestWindowFeature(d.getWindow().FEATURE_NO_TITLE);
d.setCancelable(true);
d.setContentView(R.layout.sharing);
final Button btnFacebook = (Button) d.findViewById(R.id.btnFacebook);
final Button btnEmail = (Button) d.findViewById(R.id.btnEmail);
btnEmail.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
if (!btnEmail.isSelected()) {
btnEmail.setSelected(true);
} else {
btnEmail.setSelected(false);
}
saveBtnFlag = 1;
// Check if email id is available-------------
AccountManager manager = AccountManager
.get(DrawAppActivity.this);
Account[] accounts = manager.getAccountsByType("com.google");
Account account = CommonFunctions.getAccount(manager);
if (account.name != null) {
emailSendingTask eTask = new emailSendingTask();
eTask.execute();
if (CommonFunctions.createDirIfNotExists(getResources()
.getString(R.string.path)))
{
tempImageSaving(
getResources().getString(R.string.path),
getCurrentImage());
}
Intent sendIntent;
sendIntent = new Intent(Intent.ACTION_SEND);
sendIntent.setType("application/octet-stream");
sendIntent.setType("image/jpeg");
sendIntent.putExtra(Intent.EXTRA_EMAIL,
new String[] { account.name });
sendIntent.putExtra(Intent.EXTRA_SUBJECT, "Drawing App");
sendIntent.putExtra(Intent.EXTRA_TEXT, "Check This Image");
sendIntent.putExtra(Intent.EXTRA_STREAM,
Uri.parse("file://" + tempPath.getPath()));
List<ResolveInfo> list = getPackageManager()
.queryIntentActivities(sendIntent,
PackageManager.MATCH_DEFAULT_ONLY);
if (list.size() != 0) {
startActivity(Intent.createChooser(sendIntent,
"Send Email Using:"));
}
else {
AlertDialog.Builder confirm = new AlertDialog.Builder(
DrawAppActivity.this);
confirm.setTitle(R.string.app_name);
confirm.setMessage("No Email Sending App Available");
confirm.setPositiveButton("Set Account",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,
int which) {
dialog.dismiss();
}
});
confirm.show();
}
} else {
AlertDialog.Builder confirm = new AlertDialog.Builder(
DrawAppActivity.this);
confirm.setTitle(R.string.app_name);
confirm.setMessage("No Email Account Available!");
confirm.setPositiveButton("Set Account",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,
int which) {
Intent i = new Intent(
Settings.ACTION_SYNC_SETTINGS);
startActivity(i);
dialog.dismiss();
}
});
confirm.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,
int which) {
dialog.dismiss();
}
});
confirm.show();
}
}
});
btnFacebook.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
if (!btnFacebook.isSelected()) {
btnFacebook.setSelected(true);
} else {
btnFacebook.setSelected(false);
}
saveBtnFlag = 1;
// if (connection.isInternetOn()) {
if (android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED)) {
getCurrentImage();
Intent i = new Intent(DrawAppActivity.this,
FaceBookAuthentication.class);
i.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
startActivity(i);
}
else {
ShowAlertMessage.showDialog(DrawAppActivity.this,
R.string.app_name, R.string.Sd_card,
R.string.button_retry);
}
}
});
d.show();
}
public void tempImageSaving(String tmpPath, byte[] image) {
Random rand = new Random();
tempfile = new File(Environment.getExternalStorageDirectory(), tmpPath);
if (!tempfile.exists()) {
tempfile.mkdirs();
}
tempPath = new File(tempfile.getPath(), "DrawApp" + rand.nextInt()
+ ".jpg");
try {
FileOutputStream fos1 = new FileOutputStream(tempPath.getPath());
fos1.write(image);
fos1.flush();
fos1.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
sendBroadcast(new Intent(
Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://" + Environment.getExternalStorageDirectory())));
}
public byte[] getCurrentImage() {
Bitmap b = drawingSurface.getBitmap();
ByteArrayOutputStream stream = new ByteArrayOutputStream();
b.compress(Bitmap.CompressFormat.PNG, 100, stream);
byteArray = stream.toByteArray();
return byteArray;
}
private class emailSendingTask extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
progressDialog = new ProgressDialog(DrawAppActivity.this);
progressDialog.setTitle(R.string.app_name);
progressDialog.setMessage("Saving..Please Wait..");
// progressDialog.setIcon(R.drawable.icon);
progressDialog.show();
}
@Override
protected String doInBackground(String... urls) {
String response = "";
try {
if (android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED)) {
response = "Yes";
} else {
ShowAlertMessage.showDialog(DrawAppActivity.this,
R.string.app_name, R.string.Sd_card,
R.string.button_retry);
}
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
@Override
protected void onPostExecute(String result) {
if (result.contains("Yes")) {
getCurrentImage();
}
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://"
+ Environment.getExternalStorageDirectory())));
progressDialog.cancel();
}
}
private class ImageSavingTask extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
progressDialog = new ProgressDialog(DrawAppActivity.this);
progressDialog.setTitle(R.string.app_name);
progressDialog.setMessage("Saving..Please Wait..");
// progressDialog.setIcon(R.drawable.icon);
progressDialog.show();
}
@Override
protected String doInBackground(String... urls) {
String response = "";
try {
if (android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED)) {
response = "Yes";
} else {
ShowAlertMessage.showDialog(DrawAppActivity.this,
R.string.app_name, R.string.Sd_card,
R.string.button_retry);
}
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
@Override
protected void onPostExecute(String result) {
if (result.contains("Yes")) {
getCurrentImage();
if (CommonFunctions.createDirIfNotExists(getResources()
.getString(R.string.path)))
{
saveImageInSdCard(getResources().getString(R.string.path),
getCurrentImage());
}
}
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://"
+ Environment.getExternalStorageDirectory())));
progressDialog.cancel();
}
}
Для приложения facebook используйте facebook SDK
Краткий ответ: Нет, вы должны перебрать список.
Длинный ответ: вероятность выбора определенного предмета зависит от количества предметов, которые соответствуют вашим критериям. Таким образом, вы должны отсканировать весь список.
То, что я бы предложил сделать, это собрать все соответствующие элементы в список, а затем взять случайный индекс. Я нахожу это более читабельным и менее запутанным, чем сортировка по случайному числу.
public Category CatByName(string nm)
{
string name = nm.ToUpper();
var matching = Categories.Where(x => x.CategoryName.Contains(name)).ToList();
if (matching.Count == 0)
{
return null;
}
Random rnd = new Random();
return matching[rnd.Next(matching.Count)];
}