i am creating a news App which i the content of the news is more than 2000 words, my problem is, i want to divide the content and put images in between them.
something like this
Note:
Both the images and text are coming from firebase...
i want to able to do irrespective the length of the words
You can use RichText widget for this types of complex UI.
RichText(
text: TextSpan(
children: [
TextSpan( text: "Some Text...", ),
WidgetSpan( child:
Image.network(src),
),
TextSpan( text: "Some Text...", ),
],
),
),
To cut a big sentence you can use the split method and create a list and save it as 2 different strings like
List<String> stringList = verylongSentence.split(" ");
int start = 0;
int end = 20;//get first 20 words
/// sublist of stringList
final joinedWords = stringList.sublist(start, end);
/// join the list with space
String _content1 = joinedWords.join(" ");
String _content2 = stringList.sublist(end).join(" ");
Related
I have the following function, where within a ListBody I map List values, I have a time parameter that returns a time. This contains unnecessary digits and I want to format it.
In other normal List situations I use the function
var timeFormat = DateFormat("HH:mm");
String timetest = timeFormat.format(my_data);
How can I implement my above function to format the time in the below RichText, where I enter data into TextSpan from the map, and cannot build it as a var outside and then call it in?
var mappedValues = ListBody(
children: [...mappedList.map((m) => RichText (
text: TextSpan(
children: <TextSpan> [
TextSpan(text: m.time!.toLocal().toString(), style: TextStyle(
fontSize: 18 ,
fontWeight: FontWeight.w400,
color: Color(0xff2F2F2F),
fontFamily: 'DMSans'
)
),
]
)))]);
Thank you
Update
Example of initial output
2022-03-05 23:24:00.000
My function will turn it to
23:24
Then you should be able to create a method within this widget that takes the Datetime (m.time) as input and returns the formatted time, as:
String getFormattedTime(DateTime time) {
var timeFormat = DateFormat("HH:mm");
String timePortion = timeFormat.format(time);
return timePortion;
}
Then inside your widget just call it:
TextSpan(text: getFormattedTime(m.time!))
You could also move this method into a common utility class so you can reuse it throughout your app. Let me know if that’s what you looking for and works for your purposes.
Check out this Gist (make sure to run it through DartPad) that I created that illustrates my point. Another suggestion would be to use ListView in favor or ListBody as it is more robust.
You should get output that looks like this:
Let me know if that's clear.
I have text in my app that I want to color differently as time goes on. I did this by using RichText widget with a separate text span for each character and a timer that will then update the the state and repaint all of the text spans appropriately. This works so long as the text isn't too long. It starts to break at around 7-10k characters text.
In order to optimize this I decided to use the VisibilityDetector library because text that isn't visible doesn't need to be colored differently. So I chunked the text and put each chunk in its own visibility detector, and when it isn't visible I just set the text using a Text widget. This works, but a single line will get cut off halfway through and start on the next line since they're separate widgets.
What I would like to do is pass the TextSpan as a child of the VisibilityDetector, but this gives the error that TextSpan is not a subtype of the type Widget. Is there any way to do what I want to do?
This is the type of widget tree I would like to have:
String myText = '';
RichText(
text: TextSpan(
children: myText.chunk().mapIndexed((chunkIndex, chunkText) {
return WidgetSpan(
child: VisibilityDetector(
onVisibilityChanged: (info) => _handleVisibilityChanged(),
child: !chunkIsVisible ?
Text(chunkText) :
TextSpan( //This breaks because its not a subtype of Widget
children: chunkText.characters.mapIndexed((charIndex, char) {
return TextSpan(
text: char,
style: _styleTextBasedOnIndex((chunkIndex * ChunkSize) + charIndex)
)
}
)
)
)
}
)
)
I think you can do this to pass the error:
String myText = '';
RichText(
text: TextSpan(
children: myText.chunk().mapIndexed((chunkIndex, chunkText) {
return WidgetSpan(
child: VisibilityDetector(
onVisibilityChanged: (info) => _handleVisibilityChanged(),
child: !chunkIsVisible ?
Text(chunkText) :
RichText(text: TextSpan( // Use another RichText
children: chunkText.characters.mapIndexed((charIndex, char) {
return TextSpan(
text: char,
style: _styleTextBasedOnIndex((chunkIndex * ChunkSize) + charIndex)
)
}
)
)
)
)
}
)
)
I was wondering if there was a way to customize a TextFormField with more accuracy. I don't want to change the whole text color, but only part of it. For instance, below is the above mention TextFormField and I want to highlight "には" (ie what is between curly braces) by adding a red color. I would like to avoid creating multiple TextFormFields to do this because it will be a mess to assemble the text afterwards but I don't know if it is possible.
WARNING
I am not looking for the RichText widget since I want to customize a TextFormField Widget or any Widget with an editable text.
This Widget is used in a List so I would like not to use a "preview" widget with my input widget.
AND
I don't need a full RichTextEditor since the User should not be able to modify the color. Only parts between curly braces should automatically be colorised.
Looking forwards to see what kind of solutions you guys could come up with !
I've finally found a gist that match my request. For those who are searching an answer to my question, you seems to have to override EditableText (How to change color of particular text in a text field dynamically?). But, it's only a draft and it is not working correctly as for today. I'll try to follow this path and add my answer on this post.
EDIT:
The only thing you have to change to this answer is the following:
#override
TextSpan buildTextSpan() {
final String text = textEditingValue.text;
int textLength = text.length;
if (widget.annotations != null && textLength > 0) {
var items = getRanges();
var children = <TextSpan>[];
for (var item in items) {
if (item.range.end < textLength) {
children.add(
TextSpan(style: item.style, text: item.range.textInside(text)),
);
} else if (item.range.start <= textLength) {
children.add(
TextSpan(
style: item.style,
text: TextRange(start: item.range.start, end: text.length)
.textInside(text)),
);
}
}
return new TextSpan(style: widget.style, children: children);
}
return new TextSpan(style: widget.style, text: text);
}
}
Explanation:
You simply have to correct the buildTextSpan part. The error was raised when you delete a character because the Range could raise an exception when the range end was not meet.
This might not be exactly what you want, but may be this can help you get started in a way.
Use RichText widget.
var text = new RichText(
text: new TextSpan(
style: new TextStyle(
fontSize: 10.0,
),
children: <TextSpan>[
new TextSpan(text: 'Text1'),
new TextSpan(text: 'Text2', style: new TextStyle(),
],
),
);
I'm trying to display formatted text that is created dynamically in the app. It is the result of a diff calculation and I can't see how RichText or any of the markdown formats would work. It doesn't seem like embedding HTML is the way to go, given that it seems that would display in a frame.
The code shows a static presentation of the code. I need to be able to use a list of objects and make an corresponding array of TextSpans. I'm not sure there is a way to do this.
I should add that the Styles I want are what you would see if editing text in MS Word: additions are colored green and deletions are red and crossed through. This part is easy in with RichText styles, but aren't supported by Markdown.
//This list of objects has the data I use will use to create the TextSpans.
List<DiffString> diffOut = diff(
oldStr,
newStr,
" ",
).pieces;
//
RichText(
text: TextSpan(
children: <TextSpan>[
TextSpan(
text: 'Hello ',
style: normalStyle,
),
TextSpan(
text: 'added',
style: addedStyle,
),
TextSpan(
text: 'deleted',
style: deletedStyle,
),
TextSpan(
text: ' \n\n',
style: normalStyle,
),
//TextSpan(text: 'default is messed up'),
],
),
),
pskink answered my question but then deleted it, so I'm posting it here. And yes, it just needed to map it like he said. Thanks!
/////////Here:
all you need is a List of TextSpans created by your diff calculation method and pass it as children: myListOfTextSpanDiffs - so for example: var myListOfTextSpanDiffs = diffOut.map(...).toList()
For example, I may have one RichText in current widget tree, that looks like
RichText(
text: TextSpan(
text: 'Hello ',
style: DefaultTextStyle.of(context).style,
children: <TextSpan>[
TextSpan(text: 'bold', style: TextStyle(fontWeight: FontWeight.bold)),
TextSpan(text: ' world!'),
],
),
)
I try to use find.text('Hello bold world!') but it doesn't work because it's not a Text.
Framework solution
I have recently contributed this feature to the Flutter framework, i.e. to the built-in finders.
find.text()
You can now enable a findRichText parameter, which will then also find standalone RichText widgets:
find.text(
'Hello bold world!',
findRichText: true,
)
Simplest solution is to put a key on the RichText and read it that way.
If that's not a good fit for whatever reason, you can use find.byWidgetPredicate and pass a function that matches RichText widgets whose text.toPlainText() returns the string you want.
Here's the find.byWidgetPredicate call.
find.byWidgetPredicate((widget) => fromRichTextToPlainText(widget) == 'Hello bold world!')
Here's the fromRichTextToPlainText helper function. Pass it the RichText widget, it will return the plain text.
String fromRichTextToPlainText(final Widget widget) {
if (widget is RichText) {
if (widget.text is TextSpan) {
final buffer = StringBuffer();
(widget.text as TextSpan).computeToPlainText(buffer);
return buffer.toString();
}
}
return null;
}
I solved for this by digging into the widget a bit more manually
final richTextWidget = tester.element(richTextFinder).widget as RichText;
print(richTextWidget.text.children);
With the children, I can assert they are generated as expected