从 Android 12(API 级别 31)开始,您可以使用
RoundedCorner
和
WindowInsets.getRoundedCorner(int
position)
即可获取
设备屏幕圆角的半径和中心点。这些 API
防止应用的界面元素在圆角屏幕上被截断
角。该框架提供了
getPrivacyIndicatorBounds()
此 API 会返回任何可见的麦克风和摄像头的有界矩形
指标。
在您的应用中实现这些 API 时,它们对具有非圆角屏幕的设备没有影响。

如需实现此功能,请使用以下代码获取 RoundedCorner
信息:
WindowInsets.getRoundedCorner(int position)
(相对于地图边界的边界值)
应用。如果应用没有占据整个屏幕,API 会应用
通过基于窗口的圆角中心点实现圆角
应用边界
以下代码段展示了应用如何避免其界面被截断
根据来自 RoundedCorner
的信息设置视图的外边距。在本课中,
则代表右上角。
// Get the top-right rounded corner from WindowInsets.
val insets = rootWindowInsets
val topRight = insets.getRoundedCorner(RoundedCorner.POSITION_TOP_RIGHT) ?: return
// Get the location of the close button in window coordinates.
val location = IntArray(2)
closeButton!!.getLocationInWindow(location)
val buttonRightInWindow = location[0] + closeButton.width
val buttonTopInWindow = location[1]
// Find the point on the quarter circle with a 45-degree angle.
val offset = (topRight.radius * Math.sin(Math.toRadians(45.0))).toInt()
val topBoundary = topRight.center.y - offset
val rightBoundary = topRight.center.x + offset
// Check whether the close button exceeds the boundary.
if (buttonRightInWindow < rightBoundary << buttonTopInWindow > topBoundary) {
return
}
// Set the margin to avoid truncating.
val parentLocation = IntArray(2)
getLocationInWindow(parentLocation)
val lp = closeButton.layoutParams as FrameLayout.LayoutParams
lp.rightMargin = Math.max(buttonRightInWindow - rightBoundary, 0)
lp.topMargin = Math.max(topBoundary - buttonTopInWindow, 0)
closeButton.layoutParams = lp
// Get the top-right rounded corner from WindowInsets.
final WindowInsets insets = getRootWindowInsets();
final RoundedCorner topRight = insets.getRoundedCorner(POSITION_TOP_RIGHT);
if (topRight == null) {
return;
}
// Get the location of the close button in window coordinates.
int [] location = new int[2];
closeButton.getLocationInWindow(location);
final int buttonRightInWindow = location[0] + closeButton.getWidth();
final int buttonTopInWindow = location[1];
// Find the point on the quarter circle with a 45-degree angle.
final int offset = (int) (topRight.getRadius() * Math.sin(Math.toRadians(45)));
final int topBoundary = topRight.getCenter().y - offset;
final int rightBoundary = topRight.getCenter().x + offset;
// Check whether the close button exceeds the boundary.
if (buttonRightInWindow < rightBoundary << buttonTopInWindow > topBoundary) {
return;
}
// Set the margin to avoid truncating.
int [] parentLocation = new int[2];
getLocationInWindow(parentLocation);
FrameLayout.LayoutParams lp = (FrameLayout.LayoutParams) closeButton.getLayoutParams();
lp.rightMargin = Math.max(buttonRightInWindow - rightBoundary, 0);
lp.topMargin = Math.max(topBoundary - buttonTopInWindow, 0);
closeButton.setLayoutParams(lp);
注意剪辑
如果界面填满整个显示屏,圆角可能会导致内容出现问题 剪辑。例如,图 2 在显示屏的一角显示了 在系统栏后面绘制的布局:

要避免这种情况,您可以检查圆角,并应用内边距来保持 应用内容超出设备角落的位置,如下图所示 示例:
class InsetsLayout(context: Context, attrs: AttributeSet) : FrameLayout(context, attrs) {
override fun onLayout(changed: Boolean, left: Int, top: Int, right: Int, bottom: Int) {
val insets = rootWindowInsets
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S && insets != null) {
applyRoundedCornerPadding(insets)
}
super.onLayout(changed, left, top, right, bottom)
}
@RequiresApi(Build.VERSION_CODES.S)
private fun applyRoundedCornerPadding(insets: WindowInsets) {
val topLeft = insets.getRoundedCorner(RoundedCorner.POSITION_TOP_LEFT)
val topRight = insets.getRoundedCorner(RoundedCorner.POSITION_TOP_RIGHT)
val bottomLeft = insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_LEFT)
val bottomRight = insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_RIGHT)
val leftRadius = max(topLeft?.radius ?: 0, bottomLeft?.radius ?: 0)
val topRadius = max(topLeft?.radius ?: 0, topRight?.radius ?: 0)
val rightRadius = max(topRight?.radius ?: 0, bottomRight?.radius ?: 0)
val bottomRadius = max(bottomLeft?.radius ?: 0, bottomRight?.radius ?: 0)
val windowManager = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
val windowBounds = windowManager.currentWindowMetrics.bounds
val safeArea = Rect(
windowBounds.left + leftRadius,
windowBounds.top + topRadius,
windowBounds.right - rightRadius,
windowBounds.bottom - bottomRadius
)
val location = intArrayOf(0, 0)
getLocationInWindow(location)
val leftMargin = location[0] - windowBounds.left
val topMargin = location[1] - windowBounds.top
val rightMargin = windowBounds.right - right - location[0]
val bottomMargin = windowBounds.bottom - bottom - location[1]
val layoutBounds = Rect(
location[0] + paddingLeft,
location[1] + paddingTop,
location[0] + width - paddingRight,
location[1] + height - paddingBottom
)
if (layoutBounds != safeArea && layoutBounds.contains(safeArea)) {
setPadding(
calculatePadding(leftRadius, leftMargin, paddingLeft),
calculatePadding(topRadius, topMargin, paddingTop),
calculatePadding(rightRadius, rightMargin, paddingRight),
calculatePadding(bottomRadius, bottomMargin, paddingBottom)
)
}
}
private fun calculatePadding(radius1: Int?, radius2: Int?, margin: Int, padding: Int): Int =
(max(radius1 ?: 0, radius2 ?: 0) - margin - padding).coerceAtLeast(0)
}
public class InsetsLayout extends FrameLayout {
public InsetsLayout(@NonNull Context context) {
super(context);
}
public InsetsLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
WindowInsets insets = getRootWindowInsets();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S && insets != null) {
applyRoundedCornerPadding(insets);
}
super.onLayout(changed, left, top, right, bottom);
}
@RequiresApi(Build.VERSION_CODES.S)
private void applyRoundedCornerPadding(WindowInsets insets) {
RoundedCorner topLeft = insets.getRoundedCorner(RoundedCorner.POSITION_TOP_LEFT);
RoundedCorner topRight = insets.getRoundedCorner(RoundedCorner.POSITION_TOP_RIGHT);
RoundedCorner bottomLeft = insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_LEFT);
RoundedCorner bottomRight = insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_RIGHT);
int radiusTopLeft = 0;
int radiusTopRight = 0;
int radiusBottomLeft = 0;
int radiusBottomRight = 0;
if (topLeft != null) radiusTopLeft = topLeft.getRadius();
if (topRight != null) radiusTopRight = topRight.getRadius();
if (bottomLeft != null) radiusBottomLeft = bottomLeft.getRadius();
if (bottomRight != null) radiusBottomRight = bottomRight.getRadius();
int leftRadius = Math.max(radiusTopLeft, radiusBottomLeft);
int topRadius = Math.max(radiusTopLeft, radiusTopRight);
int rightRadius = Math.max(radiusTopRight, radiusBottomRight);
int bottomRadius = Math.max(radiusBottomLeft, radiusBottomRight);
WindowManager windowManager =
(WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
Rect windowBounds = windowManager.getCurrentWindowMetrics().getBounds();
Rect safeArea = new Rect(
windowBounds.left + leftRadius,
windowBounds.top + topRadius,
windowBounds.right - rightRadius,
windowBounds.bottom - bottomRadius
);
int[] location = {0, 0};
getLocationInWindow(location);
int leftMargin = location[0] - windowBounds.left;
int topMargin = location[1] - windowBounds.top;
int rightMargin = windowBounds.right - getRight() - location[0];
int bottomMargin = windowBounds.bottom - getBottom() - location[1];
Rect layoutBounds = new Rect(
location[0] + getPaddingLeft(),
location[1] + getPaddingTop(),
location[0] + getWidth() - getPaddingRight(),
location[1] + getHeight() - getPaddingBottom()
);
if (!layoutBounds.equals(safeArea) && layoutBounds.contains(safeArea)) {
setPadding(
calculatePadding(radiusTopLeft, radiusBottomLeft,
leftMargin, getPaddingLeft()),
calculatePadding(radiusTopLeft, radiusTopRight,
topMargin, getPaddingTop()),
calculatePadding(radiusTopRight, radiusBottomRight,
rightMargin, getPaddingRight()),
calculatePadding(radiusBottomLeft, radiusBottomRight,
bottomMargin, getPaddingBottom())
);
}
}
private int calculatePadding(int radius1, int radius2, int margin, int padding) {
return Math.max(Math.max(radius1, radius2) - margin - padding, 0);
}
}
此布局确定界面是否延伸到圆角区域 并在需要添加内边距图 3 具有“Show layout bounds”(显示布局边界)开发者 选项,以便更清楚地显示应用的内边距:

为了确定这一点,此布局会计算两个矩形:safeArea
是
圆角半径内的面积,layoutBounds
为圆角半径
所有内边距。如果 layoutArea
完全包含 safeArea
,则
该布局的子项可能会被裁剪。如果是这种情况,则填充为
添加了此类代码,以确保布局始终位于 safeArea
内。
通过检查 layoutBounds
是否完全包含 safeArea
,您可以避免将
内边距。图 4
显示布局未绘制在导航栏后面时的布局。在此示例中
布局没有向下延伸到圆角内,因为
它们是否契合导航栏所占的区域。无需填充。
