如何从 Flutter TextBox 中获取原始文本 [英] How to get the raw text from a Flutter TextBox

问题描述

在 Flutter 中，在 Paragraph 或 TextPainter 布置文本后，您可以通过调用 getBoxesForSelection 获取行(或在一行内运行)的 Rects.如果您绘制实际的框，它们看起来像这样:

In Flutter, after a Paragraph or TextPainter has laid out it's text, you can get the Rects for the lines (or runs within a line) by calling getBoxesForSelection. If you draw the actual boxes they look something like this:

如何以编程方式获取每个 TextBox 中的文本?

How do I programmatically get the text within each TextBox?

推荐答案

我希望有更好的方法，但这是我目前找到的唯一方法:

I wish there were a better way, but this is the only way I have found so far:

// The TextPaint has already been laid out

// select everything
TextSelection selection = TextSelection(baseOffset: 0, extentOffset: textSpan.text.length);

// get a list of TextBoxes (Rects)
List<TextBox> boxes = _textPainter.getBoxesForSelection(selection);

// Loop through each text box
List<String> lineTexts = [];
int start = 0;
int end;
int index = -1;
for (TextBox box in boxes) {
  index += 1;

  // Uncomment this if you want to only get the whole line of text
  // (sometimes a single line may have multiple TextBoxes)
  // if (box.left != 0.0)
  //  continue;

  if (index == 0)
    continue;
  // Go one logical pixel within the box and get the position
  // of the character in the string.
  end = _textPainter.getPositionForOffset(Offset(box.left + 1, box.top + 1)).offset;
  // add the substring to the list of lines
  final line = rawText.substring(start, end);
  lineTexts.add(line);
  start = end;
}
// get the last substring
final extra = rawText.substring(start);
lineTexts.add(extra);

注意事项:

• 为了更可靠，这应该检查 TextPosition 关联.
• 这还不能处理从右到左的文本.

更新:

• 如果您要获取整行的文本，现在可以使用 LineMetrics(来自 TextPainter.computeLineMetrics())而不是 TextBox.过程类似.

• If you are getting the text of the whole line, you can use LineMetrics (from TextPainter.computeLineMetrics()) now instead of TextBox. The process would be similar.

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