Android 如何在点击按钮时将字符串插入到文本字段中的光标位置

您可以使用Select和Editable API直接操作TextField中的文本，而不是模拟键事件来插入LaTeX符号和构造.下面是一个例子，说明你如何做到这一点:

import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.padding
import androidx.compose.material.Button
import androidx.compose.material.Text
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.text.input.TextFieldValue
import androidx.compose.ui.tooling.preview.Preview

@Composable
fun MathEditor() {
    var textFieldValue by remember { mutableStateOf(TextFieldValue()) }

    Row(modifier = Modifier.padding(16.dp)) {
        Button(onClick = { insertText("\\frac{}{}") }) {
            Text(text = "Fraction")
        }
        Button(onClick = { insertText("\\sqrt{}") }) {
            Text(text = "Square Root")
        }
        // Add more buttons for other symbols and constructions
    }
    // TextField to display and edit LaTeX code
    // Here you will display the content of `textFieldValue`
}

// Function to insert text at the current cursor position in the TextField
fun insertText(textToInsert: String) {
    val selection = Selection(
        start = 0, // Set the start and end to the same value to replace the selected text
        end = 0
    )
    val newText = "$textToInsert"
    // Update the TextFieldValue with the new text inserted at the current cursor position
    // and update the cursor position after the inserted text
    // You can get the current cursor position using TextFieldValue.selection
    // and update the cursor position accordingly
    // Update `textFieldValue` here with the new value
}

@Preview
@Composable
fun MathEditorPreview() {
    MathEditor()
}

在这个例子中:

MathEditor可组合函数为不同的LaTeX符号和构造显示一行按钮. 单击按钮时调用insertText函数.此函数将指定的文本插入到文本字段中的当前光标位置. 您可以根据需要扩展insertText来处理不同的符号和 struct . 这种方法直接操作TextField的文本内容，避免了模拟关键事件的需要.