使用Jetpack Compose实现自定义软键盘输入方式；首先需要创建一个自定义的Compose View，重写onMeasure方法进行布局和测量，然后在onDraw方法内绘制自定义的键盘界面；接着，在EditText的onFocusChange回调方法内判断输入框是否获得焦点，并通过WindowManager添加一个悬浮窗口，将自定义键盘View加入悬浮窗口并显示出来；最后在自定义键盘View内实现点击事件，获取被点击的键盘按钮的文本并通过InputConnection将文本提交到EditText中。详细实现可以参考以下示例代码：

@Composable
fun CustomKeyboard(
    inputConnection: InputConnection,
) {
    val keyboardLayout = listOf(
        listOf("1", "2", "3", "4", "5", "6", "7", "8", "9", "0"),
        listOf("q", "w", "e", "r", "t", "y", "u", "i", "o", "p"),
        listOf("a", "s", "d", "f", "g", "h", "j", "k", "l", ""),
        listOf("z", "x", "c", "v", "b", "n", "m", "", "", ""),
        listOf("", "", "", "space", "", "", "", "", "", ""),
    )

    val focusManager = LocalFocusManager.current
    val windowManager = LocalWindowManager.current

    var window: PopupWindow? = null
    var currentText = ""

    fun addItem(s: String) {
        currentText += s
        inputConnection.commitText(s, 1)
    }

    fun removeItem() {
        if (currentText.isNotEmpty()) {
            currentText = currentText.substring(0, currentText.length - 1)
            inputConnection.deleteSurroundingText(1, 0)
        }
    }

    fun dismissKeyboard() {
        window?.dismiss()
    }

    val itemStyle = MaterialTheme.typography.h5.copy(fontWeight = FontWeight.Bold)

    Box(Modifier.fillMaxSize()) {
        Column(Modifier.fillMaxSize(), horizontalAlignment = Alignment.CenterHorizontally) {
            keyboardLayout.forEach { row ->
                Row {
                    row.forEach { text ->
                        when (text) {
                            "space" -> {
                                TextButton(onClick = { addItem(" ") }, modifier = Modifier.weight(0.8f).height(50.dp)) {
                                    Text(text = "space", style = itemStyle)
                                }
                            }
                            "" -> {
                                Spacer(modifier = Modifier.weight(0.1f))
                            }
                            else -> {
                                TextButton(onClick = { addItem(text) }, modifier = Modifier.weight(0.1f).height(50.dp)) {
                                    Text(text = text, style = itemStyle)
                                }
                            }
                        }
                    }
                }
                Spacer(modifier = Modifier.height(10.dp))
            }

            Row(
                modifier = Modifier.fillMaxWidth(),
                horizontalArrangement = Arrangement.Center,
            ) {
                IconButton(modifier = Modifier.weight(0.1f), onClick = { removeItem() }) {
                    Icon(Icons.Rounded.ArrowBack, null)
                }
            }
        }
    }

    val customKeyboardView = remember {
        AndroidView(
            modifier = Modifier.size(0.dp, 250.dp),
            factory = { context ->
                FrameLayout(context).apply {
                    layoutParams = FrameLayout.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT,
                        ViewGroup.LayoutParams.WRAP_CONTENT,
                        Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL
                    )