Android : 使用圆形锚定 FAB 向 BottomAppBar 添加圆角

Question

我想实现与此视图类似的效果，底部导航具有左上角和右上角圆角半径以及锚定的 FAB

Answer 1

您可以使用标准 BottomAppBar:

   <com.google.android.material.bottomappbar.BottomAppBar
        android:layout_margin="xxdp"
        app:fabAlignmentMode="center"
        app:fabCradleRoundedCornerRadius="2dp"
        app:fabCradleVerticalOffset="8dp"
        app:fabCradleMargin="8dp" />

然后更改ShapeAppearanceModel:

    BottomAppBar bottomAppBar = findViewById(R.id.bottomAppBar);
    MaterialShapeDrawable bottomBarBackground = (MaterialShapeDrawable) bottomAppBar.getBackground();
    bottomBarBackground.setShapeAppearanceModel(
            bottomBarBackground.getShapeAppearanceModel()
                    .toBuilder()
                    .setAllCorners(new RoundedCornerTreatment()).setAllCornerSizes(new RelativeCornerSize(0.5f))
                    .build());

关于新 RelativeCornerSize(0.5f) 的注意事项：它在 1.2.0-beta01 中发生了变化。之前是new RelativeCornerSize(50)

Android : 使用圆形锚定 FAB 向 BottomAppBar 添加圆角

Android : Add rounded corners to BottomAppBar with circular anchored FAB

android

custom-view

bottomnavigationview

android-bottomnav

android-bottomappbar