Jetpack compose Switch() TrackWidth、TrackStrokeWidth、ThumbDiameter

Question

也许有人可以告诉我如何在 Switch() 中设置 TrackWidth、TrackStrokeWidth、ThumbDiameter 的大小

                Switch(
                modifier = Modifier
                    .padding(end=16.dp),
                checked = auto.mainAuto.value,
                onCheckedChange = { auto.mainAuto.value = it },
                colors = SwitchDefaults.colors(
                    checkedThumbColor = white_white,
                    checkedTrackColor = Accent_Blue,
                    uncheckedThumbColor = white_white,
                    uncheckedTrackColor = Disabled_Text,
                    ),
            )

Answer 1

从 Jetpack Compose 1.0.4 开始，您无法更改它们。但是，好消息是您可以使用 Canvas API 轻松创建任何类型的开关。

例如：

这是代码：

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.animation.core.animateFloatAsState
import androidx.compose.foundation.Canvas
import androidx.compose.foundation.gestures.detectTapGestures
import androidx.compose.foundation.layout.*
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Surface
import androidx.compose.material.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.scale
import androidx.compose.ui.geometry.CornerRadius
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.drawscope.Stroke
import androidx.compose.ui.input.pointer.pointerInput
import androidx.compose.ui.platform.LocalDensity
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.dp

/*
For more designs with source code, visit: https://semicolonspace.com/jetpack-compose-samples/
 */

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            BlogPostsTheme(darkTheme = false) {
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colors.background
                ) {
                    Column(
                        modifier = Modifier.fillMaxSize(),
                        verticalArrangement = Arrangement.Center,
                        horizontalAlignment = Alignment.CenterHorizontally
                    ) {
                        Switch2()
                    }
                }
            }
        }
    }
}

@Composable
fun Switch2(
    scale: Float = 2f,
    width: Dp = 36.dp,
    height: Dp = 20.dp,
    strokeWidth: Dp = 2.dp,
    checkedTrackColor: Color = Color(0xFF35898F),
    uncheckedTrackColor: Color = Color(0xFFe0e0e0),
    gapBetweenThumbAndTrackEdge: Dp = 4.dp
) {

    val switchON = remember {
        mutableStateOf(true) // Initially the switch is ON
    }

    val thumbRadius = (height / 2) - gapBetweenThumbAndTrackEdge

    // To move thumb, we need to calculate the position (along x axis)
    val animatePosition = animateFloatAsState(
        targetValue = if (switchON.value)
            with(LocalDensity.current) { (width - thumbRadius - gapBetweenThumbAndTrackEdge).toPx() }
        else
            with(LocalDensity.current) { (thumbRadius + gapBetweenThumbAndTrackEdge).toPx() }
    )

    Canvas(
        modifier = Modifier
            .size(width = width, height = height)
            .scale(scale = scale)
            .pointerInput(Unit) {
                detectTapGestures(
                    onTap = {
                        // This is called when the user taps on the canvas
                        switchON.value = !switchON.value
                    }
                )
            }
    ) {
        // Track
        drawRoundRect(
            color = if (switchON.value) checkedTrackColor else uncheckedTrackColor,
            cornerRadius = CornerRadius(x = 10.dp.toPx(), y = 10.dp.toPx()),
            style = Stroke(width = strokeWidth.toPx())
        )

        // Thumb
        drawCircle(
            color = if (switchON.value) checkedTrackColor else uncheckedTrackColor,
            radius = thumbRadius.toPx(),
            center = Offset(
                x = animatePosition.value,
                y = size.height / 2
            )
        )
    }

    Spacer(modifier = Modifier.height(18.dp))

    Text(text = if (switchON.value) "ON" else "OFF")
}

编辑：

除了

Canvas

，您还可以使用

Box

。

Answer 2

使用

Modifier.scale(2f)

。还要添加

Modifier.padding(20.dp)

，因为它仍然按默认尺寸测量。