I am using sembast package for local data storage for a flutter app. When I search through the local data, I want to get the results regardless of whether letters are in caps or small. My current code is sensitive to capital and small letters.
Future searchFoodByField(String fieldName, String searchItem) async {
var finder = Finder(filter: Filter.matches(fieldName, searchItem));
final recordSnapshots = await _foodStore.find(
await _db,
finder: finder,
);
return recordSnapshots.map((snapshot) {
final food = Food.fromMap(snapshot.value);
food.foodId = snapshot.key;
return food;
}).toList();
}
How can it be modified to get the desired outcome?
I'm assuming you want to look for the exact word. For non-english language, you might also want to remove the accent. (diacritic package can help help here).
// Using a regular expression matching the exact word (no case)
var filter = Filter.matchesRegExp(
fieldName, RegExp('^$searchItem\$', caseSensitive: false));
You can also use a custom filter, to perform any filtering you want:
// Using a custom filter exact word (converting everything to lowercase)
searchItem = searchItem.toLowerCase();
filter = Filter.custom((snapshot) {
var value = snapshot[fieldName] as String;
return value?.toLowerCase() == searchItem;
});
Related
I want to pass a text value from my NFC tag to a variable, but want to remove the locale from the text passed to the variable (note, not remove it from the tag).
I am using the nfc_manager package.
Here is the code portion I am using that relates to scanning the tag:
NfcManager.instance.startSession(
onDiscovered: (NfcTag tag) async {
final ndef = Ndef.from(tag);
String tagRecordText = String.fromCharCodes(ndef!.cachedMessage!.records[0].payload);
NfcManager.instance.stopSession();
}
)
The first byte is the length of the characters of the language string
So this should work (my dart is not that good)
var payload = ndef!.cachedMessage!.records[0].payload;
var sub = payload.sublist(payload[0]+ 1);
String tagRecordText = String.fromCharCodes(sub);
The detail specs of a Text Record
For interaction with an API, I need to pass the course code in <string><space><number> format. For example, MCTE 2333, CCUB 3621, BTE 1021.
Yes, the text part can be 3 or 4 letters.
Most users enter the code without the space, eg: MCTE2333. But that causes error to the API. So how can I add a space between string and numbers so that it follows the correct format.
You can achieve the desired behaviour by using regular expressions:
void main() {
String a = "MCTE2333";
String aStr = a.replaceAll(RegExp(r'[^0-9]'), ''); //extract the number
String bStr = a.replaceAll(RegExp(r'[^A-Za-z]'), ''); //extract the character
print("$bStr $aStr"); //MCTE 2333
}
Note: This will produce the same result, regardless of how many whitespaces your user enters between the characters and numbers.
Try this.You have to give two texfields. One is for name i.e; MCTE and one is for numbers i.e; 1021. (for this textfield you have to change keyboard type only number).
After that you can join those string with space between them and send to your DB.
It's just like hack but it will work.
Scrolling down the course codes list, I noticed some unusual formatting.
Example: TQB 1001E, TQB 1001E etc. (With extra letter at the end)
So, this special format doesn't work with #Jahidul Islam's answer. However, inspired by his answer, I manage to come up with this logic:
var code = "TQB2001M";
var i = course.indexOf(RegExp(r'[^A-Za-z]')); // get the index
var j = course.substring(0, i); // extract the first half
var k = course.substring(i).trim(); // extract the others
var formatted = '$j $k'.toUpperCase(); // combine & capitalize
print(formatted); // TQB 1011M
Works with other formats too. Check out the DartPad here.
Here is the entire logic you need (also works for multiple whitespaces!):
void main() {
String courseCode= "MMM 111";
String parsedCourseCode = "";
if (courseCode.contains(" ")) {
final ensureSingleWhitespace = RegExp(r"(?! )\s+| \s+");
parsedCourseCode = courseCode.split(ensureSingleWhitespace).join(" ");
} else {
final r1 = RegExp(r'[0-9]', caseSensitive: false);
final r2 = RegExp(r'[a-z]', caseSensitive: false);
final letters = courseCode.split(r1);
final numbers = courseCode.split(r2);
parsedCourseCode = "${letters[0].trim()} ${numbers.last}";
}
print(parsedCourseCode);
}
Play around with the input value (courseCode) to test it - also use dart pad if you want. You just have to add this logic to your input value, before submitting / handling the input form of your user :)
I have stored in shared_preferences key value pairs like below....
item_001 = 'some data'
item_103 = 'some data'
item_007 = 'some data'
item_059 = 'some data'
I am trying get all the stored values begins with item_***
I know how to read and write with single key (example below)... but I am trying to get a list of items from shared_preferences where the key name begins with item_.
string
read: final myString = prefs.getString('my_string_key') ?? '';
write: prefs.setString('my_string_key', 'hello');
stringList
read: final myStringList = prefs.getStringList('my_string_list_key') ?? [];
write: prefs.setStringList('my_string_list_key', ['horse', 'cow', 'sheep']);
due to some reason, I don't want to store all the items in one list.... I want to store each item with separate key.
I searched in google and in stackoverflow, unfortunately no where found proper answer....
also I looked into this one, but not understood how to implement partial key search...
esetintis got to this first but I doodled this code so I guess I'll share it. But yes, you have to first get all of the keys in the shared preferences and then get the value for matching keys.
SharedPreferences prefs = await SharedPreferences.getInstance();
Set<String> keys = prefs.getKeys().where((key)=>key.startsWith('item_'));
for (String key in keys) {
String value = prefs.getString(key); // Throws an error if you store something other than a String
// Do your thing
}
I don't think there is a way to make such query. However, you can tackle the issue with some extra steps.
1 step :
Get all keys from SharedPreferences with prefs.getKeys() method. This will return a Set of keys. Now you can assign a List<String> keys = prefs.getKeys().where((k)=>k.startsWith('item_')) which will have the keys you want to get from the Storage.
2nd :
Iterate the filtered array and get the values you want by calling SharedPreferences, and save them to some variable.
Assuming that you have all the keys in a list, for example:
List<String> keys = ['item_001', 'item_103', 'item_007', 'item_059', 'other_key', 'blablabla'];
Now, you could iterate through all of them and checking the ones that starts with "item_", like this:
var itemKeys = [];
for(var i=0;i<keys.length;i++){
if (keys[i].startsWith('item_')) {
itemKeys.add(keys[i]);
}
}
print(itemKeys); // [item_001, item_103, item_007, item_059]
In the above example, itemKeys contains all the needed keys for you. What you could also do is to add the proper logic to fetch values from the shared preferences inside the if statement in the loop:
var result = [];
for(var i=0;i<keys.length;i++){
if (keys[i].startsWith('item_')) {
result.add(prefs.getString(keys[i]) ?? '');
}
}
result should contain what are you looking for.
How to display Unicode Smiley from json response dynamically in flutter. It's display properly when i declare string as a static but from dynamic response it's not display smiley properly.
Static Declaration: (Working)
child: Text("\ud83d\ude0e\ud83d\ude0eThis is just test notification..\ud83d\ude0e\ud83d\ude0e\ud83d\udcaf\ud83d\ude4c")
Dynamic Response:
"message":"\\ud83d\\ude4c Be Safe at your home \\ud83c\\udfe0",
When i'm parse and pass this response to Text then it's consider Unicode as a String and display as a string instead of Smiley Code is below to display text with smiley:
child: Text(_listData[index].message.toString().replaceAll("\\\\", "\\"))
Already go through this: Question but it's only working when single unicode not working with multiple unicode.
Anyone worked with text along with unicode caracter display dynamically then please let me know.
Another alternate Good Solution I would give to unescape characters is this:
1st ->
String s = "\\ud83d\\ude0e Be Safe at your home \\ud83c\\ude0e";
String q = s.replaceAll("\\\\", "\\");
This would print and wont be able to escape characters:
\ud83d\ud83d Be Safe at your home \ud83c\ud83d
and above would be the output.
So what one can do is either unescape them while parsing or use:
String convertStringToUnicode(String content) {
String regex = "\\u";
int offset = content.indexOf(regex) + regex.length;
while(offset > 1){
int limit = offset + 4;
String str = content.substring(offset, limit);
// print(str);
if(str!=null && str.isNotEmpty){
String uni = String.fromCharCode(int.parse(str,radix:16));
content = content.replaceFirst(regex+str,uni);
// print(content);
}
offset = content.indexOf(regex) + regex.length;
// print(offset);
}
return content;
}
This will replace and convert all the literals into unicode characters and result and output of emoji:
String k = convertStringToUnicode(q);
print(k);
😎 Be Safe at your home 🈎
That is above would be the output.
Note: above answer given would just work as good but this is just when you want to have an unescape function and don't need to use third-party libraries.
You can extend this using switch cases with multiple unescape solutions.
Issue resolved by using below code snippet.
Client client = Client();
final response = await client.get(Uri.parse('YOUR_API_URL'));
if (response.statusCode == 200) {
// If the server did return a 200 OK response,
// then parse the JSON.
final extractedData = json.decode(response.body.replaceAll("\\\\", "\\"));
}
Here we need to replace double backslash to single backslash and then decode JSON respone before set into Text like this we can display multiple unicode like this:
final extractedData = json.decode(response.body.replaceAll("\\",
"\"));
Hope this answer help to other
I want to get a sub range by character index from the parent paragraph. What's the suggest way to do so? The only method I found to shrink the range is "Paragraph.search()"
ref:
Word.Range: https://learn.microsoft.com/en-us/javascript/api/word/word.range?view=office-js
Word.Paragraph: https://learn.microsoft.com/en-us/javascript/api/word/word.paragraph?view=office-js
My use case:
I'm writing a markdown plugin for MS Word and I'm trying to parse the following paragraph.
A **bold** word
The output from markdown parser is {style:"strong",start:2,end:9}. So I want to apply bold style to the targeting range.
Found a way just now. The key is passing an empty separator to Paragraph.getTextRanges([""]) I'm not sure how bad the performance would be.
const makeBold = async (paragraph:Word.Paragraph,start:number,end:number) => {
const charRanges = paragraph.getTextRanges([""])
charRanges.load()
await charRanges.context.sync()
const targetRange = charRanges.items[start].expandTo(charRanges.items[end])
targetRange.load()
await targetRange.context.sync()
targetRange.font.bold = true
await targetRange.context.sync()
}
The existing answer didn't work for me (it seems like getTextRanges() no longer accepts empty strings).
So I have adapted the answer to use paragraph.search() instead.
async function getRangeByIndex(paragraph: Word.Paragraph, start: number, end: number) {
const charRanges = paragraph.search('?', { matchWildcards: true })
charRanges.load()
await charRanges.context.sync()
const targetRange = charRanges.items[start].expandTo(charRanges.items[end])
targetRange.load()
await targetRange.context.sync()
return targetRange
}