使用樣式的範例

下列文件包含使用樣式建立特定類型元件的範例。

注意： 這些範例不會從主題中提取值，僅用於說明樣式的功能。在專案中使用這些範例時，請將常見的可設定主題顏色、形狀和字體排版樣式擷取至主題類別。

按鈕

樣式可用於建立多種按鈕，這些按鈕可能與標準 Material 元件不同。

基本按鈕

請考慮將下列按鈕定義為不同類型按鈕的基礎：

@Composable
fun BaseButton(
    onClick: () -> Unit,
    modifier: Modifier = Modifier,
    style: Style = Style,
    enabled: Boolean = true,
    interactionSource: MutableInteractionSource? = remember {
        MutableInteractionSource()
    },
    content: @Composable RowScope.() -> Unit
) {
    val styleState = rememberUpdatedStyleState(interactionSource) {
        it.isEnabled = enabled
    }
    Row(
        modifier = modifier
            .semantics(properties = {
                role = Role.Button
            })
            .clickable(
                enabled = enabled,
                onClick = onClick,
                interactionSource = interactionSource,
                indication = null,
            )
            .styleable(styleState, baseButtonStyle, style),
        content = content,
        verticalAlignment = Alignment.CenterVertically
    )
}
Button.kt

將滑鼠游標懸停在「翻譯」按鈕上

如要定義按鈕，並在滑鼠懸停時移動背景，請使用下列程式碼：

圖 1. 按鈕，背景會在滑鼠懸停時翻譯。

@Preview
@Composable
fun HoverButtonExample() {
    Box(
        modifier = Modifier.padding(32.dp),
        contentAlignment = Alignment.Center
    ) {
        BaseButton(
            onClick = {},
            style = Style {
                background(Color.Transparent)
                shape(RoundedCornerShape(0.dp))
                border(1.dp, Color.Black)
                contentColor(Color.Black)
                fontSize(16.sp)
                fontWeight(FontWeight.Light)
                letterSpacing(1.sp)
                contentPadding(vertical = 13.dp, horizontal = 20.dp)
                dropShadow(
                    Shadow(
                        spread = 0.dp, color = Color(0xFFFFE54C),
                        radius = 0.dp,
                        offset = DpOffset(7.dp, 7.dp)
                    )
                )
                hovered {
                    animate(tween(200)) {
                        dropShadow(
                            Shadow(
                                spread = 0.dp, color = Color(0xFFFFE54C),
                                radius = 0.dp,
                                offset = DpOffset(0.dp, 0.dp)
                            )
                        )
                    }
                }
                pressed {
                    animate(tween(200)) {
                        dropShadow(
                            Shadow(
                                spread = 0.dp, color = Color(0xFFFFE54C),
                                radius = 0.dp,
                                offset = DpOffset(0.dp, 0.dp)
                            )
                        )
                    }
                }
            }
        ) {
            BaseText("Button 52")
        }
    }
}
Examples.kt

圓角景深按鈕，帶有陰影動畫

如要建立具有深度按壓效果的按鈕，在 pressed 上將陰影向上和向下平移，請按照下列步驟操作：

圖 2. 按鈕具有深度效果，按下時會平移陰影圖層。

@Preview
@Composable
fun ShadowAnimationButton() {
    Box(modifier = Modifier.padding(32.dp)) {
        val density = LocalDensity.current
        val buttonStyle = Style {
            background(Color(0xFFFBEED0))
            border(2.dp, Color(0xFF422800))
            shape(RoundedCornerShape(30.dp))
            dropShadow(
                Shadow(
                    color = Color(0xFF422800), offset = DpOffset(4.dp, 4.dp),
                    radius = 0.dp, spread = 0.dp
                )
            )
            contentColor(Color(0xFF422800))
            fontWeight(FontWeight.SemiBold)
            fontSize(18.sp)
            contentPaddingHorizontal(25.dp)
            externalPadding(8.dp)
            height(50.dp)
            textAlign(TextAlign.Center)
            hovered {
                animate {
                    background(Color.White)
                }
            }
            pressed {
                animate {
                    dropShadow(
                        Shadow(
                            color = Color(0xFF422800),
                            offset = DpOffset(2.dp, 2.dp),
                            radius = 0.dp,
                            spread = 0.dp
                        )
                    )
                    translation(with(density) { 2.dp.toPx() }, with(density) { 2.dp.toPx() })
                }
            }
        }
        BaseButton(
            onClick = {},
            style = buttonStyle
        ) {
            BaseText("Button 74")
        }
    }
}
Examples.kt

多個層疊樣式，並搭配按下動畫

下列程式碼會建立具有深度按下效果的按鈕 (使用樣式)，其中包含多個樣式層，且全都使用相同的 StyleState：

圖 3. 按鈕具有按下時的深度效果，並有多個樣式層。

@Preview
@Composable
fun MultipleStylesButton() {
    val interactionSource = remember { MutableInteractionSource() }
    val styleState = remember(interactionSource) { MutableStyleState(interactionSource) }
    val density = LocalDensity.current

    Box(
        modifier = Modifier
            .styleable(styleState) {
                size(200.dp, 48.dp)
                externalPadding(32.dp)
            }
            .clickable(interactionSource, indication = null) {},
        contentAlignment = Alignment.Center
    ) {
        val edgeStyle = Style {
            fillSize()
            shape(RoundedCornerShape(16.dp))
            background(Color(0xFF1CB0F6))
        }

        val frontStyle = Style {
            fillSize()
            background(Color(0xFF1899D6))
            shape(RoundedCornerShape(16.dp))
            contentPadding(vertical = 12.dp, horizontal = 16.dp)
            translationY(with(density) { (-4).dp.toPx() })
            pressed {
                animate {
                    translationY(with(density) { (0).dp.toPx() })
                }
            }
        }
        Box(modifier = Modifier.semantics(properties = {
            role = Role.Button
        }).styleable(styleState, edgeStyle)) {
            Box(
                modifier = Modifier
                    .styleable(styleState, frontStyle),
                contentAlignment = Alignment.Center
            ) {
                BaseText(
                    "Button 19".toUpperCase(Locale.current),
                    style = Style {
                        contentColor(Color.White)
                        fontSize(15.sp)
                        fontWeight(FontWeight.Bold)
                        letterSpacing(0.8.sp)
                    }
                )
            }
        }
    }
}
Examples.kt