CornerCutLinearLayout

CornerCutLinearLayout extends LinearLayout. It allows cutting parent corners with different shapes and build proper shadow for complex shapes.
It also allows cutting each child's corners.

Developed by Devlight company.

Additionally, using available properties and custom providers, those cuts may be turned into cutouts of different shapes, sizes, etc.
Widget's sole purpose is to use with children with no transformations (like rotation, scale, matrix transformations).

Amongst additional features:

RTL support
child layout parameters that allow overriding default parent parameters
custom shadow
custom dividers & providers
custom cutouts & providers
custom view visible area provider

Installation

Step 1. Add the JitPack repository to your project's build.gradle file:

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
    }
}

subprojects { 
    repositories {
        ...
        maven {
            ...
            url = "https://jitpack.io"
        }
    }
}

Step 2. Add the following dependency to your target module's build.gradle file:

dependencies {
    implementation 'com.github.Devlight:CornerCutLinearLayout:1.0.5'
}

Usage

For simple quick usage that covers most use cases, see Basics section below.
For more complex usage section Advanced might be useful.

Basics

Declaration in XML

All widget attributes start with ccll_ prefix. Children's layout attributes starts with layout_ccll_ prefix, respectively. There are plenty of attributes. In order to facilitate their usage, they separated into few categories with start prefix:

ccll_ or ccll_corner_cut - global widget attributes
ccll_child_ - global child cut attributes
ccll_custom_shadow - custom shadow attributes
ccll_custom_divider - custom divider attributes

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    android:id="@+id/ccll_kotlin_synthetic_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#FFFFFF"
    android:orientation="vertical"

    app:ccll_corner_cut_flag="start_top|end_bottom"
    app:ccll_corner_cut_size="24dp"
    app:ccll_corner_cut_type="oval"

    app:ccll_child_corner_cut_type="oval_inverse"

    app:ccll_custom_shadow_color="#FEB545"
    app:ccll_custom_shadow_radius="16dp">

    <View
        android:layout_width="match_parent"
        android:layout_height="50dp" />

    <View
        android:layout_width="match_parent"
        android:layout_height="50dp" />
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Declaration in Code (Kotlin)

All XML attributes correspond to CornerCutLinearLayout's property or function.

with(ccll_kotlin_synthetic_view) {
    val density = resources.displayMetrics.density
    cornerCutFlag = combineFlags(CornerCutFlag.START_TOP, CornerCutFlag.END_BOTTOM)
    setCornerCutSize(density * 24)
    setCornerCutType(CornerCutType.OVAL)
    setChildCornerCutType(CornerCutType.OVAL_INVERSE)
    customShadowColor = Color.parseColor("#FEB545")
    customShadowRadius = density * 16
}

Visual result would be follow:

Corner Cut Anatomy

By default CornerCutType.OVAL is used for both parent corner and child cuts. Corner cut are bounded to its personal dimensions - depth and length.

Depth - relative to orientation width of the cutout bounds.
Length - relative to orientation height of the cutout bounds.

Each of 4 parent corner cuts dimensions could be specified individually.
Children's corner cuts could have separate dimensions for ChildSideCutFlag.START and ChildSideCutFlag.END sides. Children's corner cuts could also be rotated. The rotation angle could optionally be mirrored.

As you may notice, parent corner cuts are purely bounded to corners, but child corner cut bounds are "mirrored". Indeed, each child corner cut forms a mirrored path. This strategy was chosen in order for children could separately override the contact part of the corner cut.

Also, note that depth and length depends on widget's layout direction (LinearLayout.LAYOUT_DIRECTION_LTR or LinearLayout.LAYOUT_DIRECTION_RTL) and orientation (LinearLayout.VERTICAL or LinearLayout.HORIZONTAL).

Corner Cut Types

There are 5 default corner cut types for parent and children corners*.

Oval.

Oval Inverse.

Rectangle.**

Rectangle Inverse.**

Bevel.

* - Each child corner type, in fact, is mirrored and combined into a path from the respective corner cut types of contact children.
** - Rectangle types support an internal corner radius. There are respective attributes and view properties for both parent and child cuts.

Layout Parameters

Each child can override parent defined properties and attributes related to the corner cuts.

In the examples below, parent CornerCutLinearLayout has ccll_child_corner_cut_type = oval_inverse and the middle children override each corner (different types)

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_child_corner_cut_type="oval_inverse">
    ...
    <View
        ...
        app:layout_ccll_start_top_corner_cut_type="oval"
        app:layout_ccll_end_top_corner_cut_type="bevel"
        app:layout_ccll_end_bottom_corner_cut_type="rectangle"
        app:layout_ccll_start_bottom_corner_cut_type="rectangle_inverse"/>
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Edge Child

There also special layout params for the first and last child. For example in a vertical orientation, when the top and bottom children are not aligned to parent top and bottom respectively they can override contact cut* with the parent.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    android:gravity="center"
    app:ccll_child_corner_cut_type="oval_inverse">
    <View
        ...
        app:layout_ccll_edge_child_parent_contact_corner_cut_type="oval"/>
        ...
    <View
        ...
        app:layout_ccll_edge_child_parent_contact_corner_cut_type="rectangle_inverse"/>
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

In case edge child is aligned to the respective side, they could optionally override parent corner cut type**.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_corner_cut_type="bevel">
    <View
        ...
        app:layout_ccll_start_top_corner_cut_type="oval"
        app:layout_ccll_end_top_corner_cut_type="rectangle"
        app:layout_ccll_edge_child_could_override_parent_corner_cut_type_if_edge_aligned="true"/>
        ...
    <View
        ...
        app:layout_ccll_start_bottom_corner_cut_type="rectangle_inverse"
        app:layout_ccll_edge_child_could_override_parent_corner_cut_type_if_edge_aligned="true"/>
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

* - By default specified ccll_child_corner_cut_type is used for child-parent contact if not overridden by edge child.
** - Note that only type of parent corner cut type is overridden, while other properties (depth, length, etc.) are stay preserved.

Extra Child Corner Cut Properties

There are next extra child corner cut properties:

Depth & Length Offset
Corner Cut Rotation

Depth & Length Offset

Each side of child corner cuts could have different depth and length offset (see anatomy above).

Example 1 - Depth Offset

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_child_corner_cut_depth_offset="@dimen/offset_24"
    app:ccll_child_corner_cut_type="oval_inverse">
    ...
    <View
        ...
        app:layout_ccll_end_bottom_corner_cut_type="oval"
        app:layout_ccll_end_top_corner_cut_type="rectangle_inverse"
        app:layout_ccll_start_bottom_corner_cut_type="bevel"
        app:layout_ccll_start_top_corner_cut_type="rectangle" />
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Example 2 - Depth & Length Offset

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_child_corner_cut_type="bevel"
    app:ccll_child_end_side_corner_cut_depth_offset="@dimen/depth_offset"
    app:ccll_child_start_side_corner_cut_length_offset="@dimen/length_offset"
    app:ccll_corner_cut_type="bevel">
    <View
        ...
        android:layout_marginTop="@dimen/offset_8"
        android:layout_marginBottom="@dimen/offset_8"/>
    <View
        ...
        android:layout_marginTop="@dimen/offset_8"
        android:layout_marginBottom="@dimen/offset_8"/>

    <View
        ...
        android:layout_marginTop="@dimen/offset_8"
        android:layout_marginBottom="@dimen/offset_8"/>
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Rotation

Each side could have its corner cuts rotated be specified degree. Corresponding attributes are:

ccll_child_start_side_corner_cut_rotation_degree
ccll_child_end_side_corner_cut_rotation_degree

Also, it might be necessary to keep the same mirrored corner cut angle for the both sides. For such purposes attribute ccll_is_child_corner_cut_end_rotation_mirrored_from_start_rotation might be helpful.

Each attribute has its corresponding CornerCutLinearLayout's property and/or convenience function.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_child_corner_cut_type="oval"
    app:ccll_child_end_side_corner_cut_type="oval_inverse"
    app:ccll_child_end_side_corner_cut_rotation_degree="60"
    app:ccll_child_start_side_corner_cut_rotation_degree="45">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Shadow

One of the main problem of Android's shadow is that path must be convex.

* - A path is convex if it has a single contour, and only ever curves in a single direction.

This widget allows bypass this limitation by automatically building complex shadow (event with cutouts). Of course, shadow is custom and has its pros and cons.

Pros:

Shadow has custom properties, such as offset & color (ARGB).
Supports complex non convex path.

Cons:

Shadow is artificial compared to native elevation shadow's nature. Thus, you cannot rely on global source an light position and elevation parameter.
Shadow uses view's area (padding), which you should keep in mind during layout process or dynamic change of shadow radius.
Shadow does NOT depend on view's or children's background and their transparencies, thus cannot be a composite shadow with the overlays of different levels of transparency (opacity).

By default shadow are build upon parent padded area combined with all cutouts data. It means that shadow does NOT depend on view's background, child presence or child's background. But this behavior could be changed by CustomViewAreaProvider (see Advanced section).

Shadow Padding.
You could also enable custom shadow auto padding (ccll_is_custom_shadow_auto_padding_enabled), allow or prevent custom shadow over user defined padding. (ccll_could_draw_custom_shadow_over_user_defined_padding). Last attribute works only in conjunction with enabled first attribute.

Examples:

Custom Divider

Custom Divider has similar anatomy and properties as default's LinearLayout divider. Custom dividers does not change view's dimension unlike default's LinearLayout divider did (last adds space at specified by flag position equal to divider's width or height). Custom diviers are drown over view and default dividers. You can combine default and custom divider.

Custom dividers have several advantages though:

additional show flags
line caps (ROUND, BUTT, SQUARE)
seperate start an end padding
dashed line divider (width and gap)
gravity of dashed divider (CustomDividerGravity: START, CENTER, END)
custom divider provider (see Advanced section)

Show Flags (CustomDividerShowFlag):

container_beginning - at view beginning
beginning - between contact of first view's margin and parent.
middle - between children contact margins
end - between contact of last view's margin and parent.
container_end - at view end

By default custom dividers are not taken into consideration when shadow are build.

Custom Divider attributes:

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    app:ccll_custom_divider_color="@color/divider"
    app:ccll_custom_divider_dash_gap="@dimen/divider_dash_gap"
    app:ccll_custom_divider_dash_width="@dimen/divider_dash_width"
    app:ccll_custom_divider_height="@dimen/divider_height"
    app:ccll_custom_divider_line_cap="butt"
    app:ccll_custom_divider_show_flag="middle|container_end"
    app:ccll_custom_divider_gravity="center"
    app:ccll_custom_divider_padding="@dimen/divider_padding"
    app:ccll_custom_divider_padding_start="@dimen/divider_padding_start"
    app:ccll_custom_divider_padding_end="@dimen/divider_padding_end">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Examples:

Advanced

Sometimes you might want to have even more complex visible area, divider, cutouts, etc. For such purposes there are custom providers for aforementioned subjects. All of them could be specified programatically. For your convenience, there are also a Kotlin lambda-style functions for the most of the providers.

Corner Cut Provider

CornerCutProvider allows to override each of 4 widget's corners.
Let's look at an examples.

Example 1.

As usual define our view at xml (this scenario) or create & setup it programatically.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    android:id="@+id/ccll_corner_cut_provider"
    app:ccll_corner_cut_depth="@dimen/corner_cut_depth"
    app:ccll_corner_cut_length="@dimen/corner_cut_length"
    app:ccll_corner_cut_type="bevel"/>

Set a CornerCutProvider.

ccll_corner_cut_provider.setCornerCutProvider { view, cutout, cutCorner, rectF ->
    when (cutCorner) {
        CornerCutFlag.START_TOP -> {
            rectF.inset(inset, inset) // inset - globally defined property
            cutout.moveTo(rectF.left, rectF.top)
            cutout.lineTo(rectF.right, rectF.top)
            cutout.lineTo(rectF.left, rectF.bottom)
            true // accept left top corner
        }
        
        CornerCutFlag.END_BOTTOM -> {
            // complex pacman path
            ... 
            true // accept right bottom corner
        }
        
        else -> false // skip the rest of the corners and treat them by default settings
    }
}

Here, we simply override left top and right bottom corner cuts with the custom ones. They are accepted by returning true as a last statement, otherwise respective corner would be handled by its default settings (if any).

When is necessary to compose cutout path with nested cutout pathes, use either Path.addPath() function (with different fillType) or Path.op() function with different Path.Op modes.

The result would be as follow:

Example 2. In some scenario you might need transform your cutout path (scale, rotate, skew, etc). For this purposes there is also optional function getTransformationMatrix() of CornerCutProvider interface.
In this example, there are 3 simple views with different background color below CornerCutLinearLayout with CornerCutProvider.

Also, as you can see from the image below, you could achieve animated effects by calling public function invalidateCornerCutPath() whenever it is necessary to update your view after changing your custom cutout relative values.

Aforementioned views become visible through cutout. Moreover shadow is also properly drawn around cutout. And this cutout exceeds its recommended by rectF bounds. For such purposes better use CustomCutoutProvider.

ccll_corner_cut_example_2.setCornerCutProvider(
            { view, _, _, _ ->
                val matrix = Matrix()
                val pb = view.paddedBounds
                matrix.postRotate(currentRotationAngle, pb.centerX(), pb.centerY())
                matrix // returns matrix that will be applied to cutout path. Null by default
            },
            
            { view, cutout, cutCorner, rectF ->
                when (cutCorner) {
                    CornerCutLinearLayout.CornerCutFlag.START_TOP -> {
                        with(view.paddedBounds) {
                            cutout.addRect(
                                centerX() - rectF.width() / 2.0F,
                                centerY() - rectF.height() / 2.0F,
                                centerX() + rectF.width() / 2.0F,
                                centerY() + rectF.height() / 2.0F,
                                Path.Direction.CW
                            )
                        }
                        true
                    }

                    else -> false
                }
            }
        )

Child Corner Cut Provider

ChildCornerCutProvider is almost the same as CornerCutProvider. Instead of cutCorner it has cutEdge and additionally possible contact children - relativeCutTopChild & relativeCutBottomChild.

Example 1.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    android:id="@+id/ccll_child_cut_provider_example_1"
    app:ccll_child_side_cut_flag="start"
    app:ccll_corner_cut_flag="none">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

ccll_child_cut_provider_example_1.setChildCornerCutProvider { view, cutout, _, rectF, _, _ ->
    with(cutout) {
        moveTo(rectF.centerX(), rectF.top)
        arcTo(...)
        lineTo(rectF.centerX() + rectF.width(), rectF.bottom)
        arcTo(...)
        lineTo(rectF.centerX(), rectF.top)
        val halfChordWidth = rectF.height() / 2.0F
        addCircle(...)
        moveTo(rectF.centerX() + rectF.width(), rectF.top)
        lineTo(view.paddedBounds.right - rectF.width() / 2.0F, rectF.centerY())
        lineTo(rectF.centerX() + rectF.width(), rectF.bottom)
        lineTo(rectF.centerX() + rectF.width(), rectF.top)
    }
    true // accept custom cutout
}

The result would be as follow:

Note that in this example only left side corner cuts are build with custom cutout provider. This is because providers is only called for cutSide's & cutCorner's specified by ccll_child_side_cut_flag & ccll_corner_cut_flag, respectively.

Example 2.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    android:id="@+id/ccll_child_cut_provider_example_2"
    app:ccll_child_corner_cut_type="rectangle_inverse"
    app:ccll_corner_cut_flag="none">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

ccll_showcase_custom_child_cut_provider_mixed.setChildCornerCutProvider(
    { _, _, cutSide, rectF, _, _ ->
        val matrix = Matrix()
        when (cutSide) {
            CornerCutLinearLayout.ChildSideCutFlag.START -> {
                matrix.postSkew(-0.25F, 0.0F, rectF.centerX(), rectF.centerY())
            }
            CornerCutLinearLayout.ChildSideCutFlag.END -> {
                matrix.postRotate(-10.0F, rectF.centerX(), rectF.centerY())
                matrix.postTranslate(-rectF.width() / 2.0F, 0.0F)
            }
        }
        matrix // return transformation matrix that will be applied over previously defined cutouts
    },
    
    { view, cutout, cutSide, rectF, relativeCutTopChild, _ ->
        when (cutSide) {
            CornerCutLinearLayout.ChildSideCutFlag.START -> {
                if (view.indexOfChild(relativeCutTopChild ?: return@setChildCornerCutProvider false) != 1) return@setChildCornerCutProvider false
                // cutout star path
                true // accept path for only 2 (index 1) start side cutout
            }
            CornerCutLinearLayout.ChildSideCutFlag.END -> {
                if (view.indexOfChild(relativeCutTopChild ?: return@setChildCornerCutProvider false) != 0) return@setChildCornerCutProvider false
                // cutout star path
                true // accept path for only 1 (index 0) end side cutout
            }
            else -> false
        }
    }
)

The result would be as follow:

Custom Cutout Provider

This type of provider (CustomCutoutProvider) is similar to previous cut providers. The only difference is that you could add many cutout providers and the rectF parameter in a both interface's functions return view's padded bounds.

Custom View Area Provider

CustomViewAreaProvider might be useful in case you need to show custom area of view. Posibilities are only limited by your imagination and Android hardware. May require little knowledge of path composition, path op modes, fill types, etc.

Example 1.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    ...
    android:id="@+id/ccll_custom_view_area_provider_example_1"
    app:ccll_child_side_cut_flag="none"
    app:ccll_corner_cut_flag="none"
    app:ccll_custom_shadow_color="@color/shadow_color"
    app:ccll_custom_shadow_radius="@dimen/shadow_radius">

    <TextView
        ...
        android:layout_marginEnd="@dimen/offset_48"
        android:ellipsize="end"
        android:padding="@dimen/offset_16"
        android:text="Lorem ipsum dolor sit amet..." />
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

ccll_custom_view_area_provider_example_1.setCustomViewAreaProvider { view, path, rectF ->
    // properties
    val offset = view[0].marginEnd
    val cornerRadius = rectF.height() / 4.0F
    val tailCircleRadius = cornerRadius / 2.0F
    val innerTailCircleRadius = tailCircleRadius / 2.0F
    val smallCornerRadius = cornerRadius / 4.0F
    
    // left part: round rect
    path.addRoundRect(...)
    
    // right part: tail
    path.moveTo(rectF.right - offset, rectF.top + cornerRadius)
    path.arcTo(...)
    path.lineTo(rectF.right - tailCircleRadius, rectF.centerY() - innerTailCircleRadius)
    path.lineTo(rectF.right - offset + innerTailCircleRadius, rectF.centerY() - innerTailCircleRadius)
    path.arcTo(...)
    path.lineTo(rectF.right - tailCircleRadius, rectF.centerY() + innerTailCircleRadius)
    path.arcTo(...)
    path.lineTo(rectF.right - offset, rectF.top + cornerRadius)
    path.addCircle(rectF.right - tailCircleRadius, rectF.centerY(), tailCircleRadius,  Path.Direction.CW)
    path.addCircle(rectF.right - tailCircleRadius, rectF.centerY(), innerTailCircleRadius, Path.Direction.CCW)
}

The result would be as follow:

Example 2.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    android:id="@+id/ccll_custom_view_area_provider_example_2"
    android:gravity="center_horizontal"
    android:orientation="horizontal"
    android:padding="@dimen/offset_16"
    app:ccll_child_side_cut_flag="none"
    app:ccll_corner_cut_flag="none"
    app:ccll_could_draw_custom_shadow_over_user_defined_padding="true"
    app:ccll_custom_shadow_color="@color/accent_secondary"
    app:ccll_custom_shadow_radius="@dimen/elevation_16"
    app:ccll_is_custom_shadow_auto_padding_enabled="false">

    <io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
        ...
        android:rotation="10"
        android:rotationX="35"
        android:translationX="24dp"
        app:ccll_child_side_cut_flag="none"
        app:ccll_corner_cut_type="oval_inverse"
        app:ccll_corner_cut_size="@dimen/corner_cut_size">
        ...
    </io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

    <io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
        ...
        app:ccll_corner_cut_size="@dimen/corner_cut_size_2"
        android:layout_marginStart="@dimen/offset_16"
        android:layout_marginEnd="@dimen/offset_48"/>

    <View
        ...
        android:background="#8010A7E8" />
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

In this example CornerCutLinearLayout has nested CornerCutLinearLayout (first two children) and simple view (3rd child).
First child is transformed (constantly running animation): rotated around x, y & z sequentially.
Second child is continuously animated (translation Y) as well. It also has its own CustomCutoutProvider in a form of a star.
Third child is a regular view with semi-transparent background.

Also parent CustomCutoutProvider has CustomCutoutProvider set programatically (curved lines path). In this examples we want to build shadow upon only children visible area also modifying some of them (virtual corner cuts for 3rd child).

// 1. Add Custom Cutout Provider
val waveLineCutWidth = resources.getDimension(R.dimen.offset_12)
val waveLineHeight = resources.getDimension(R.dimen.offset_48)
val halfWaveLineHeight = waveLineHeight / 2.0F
val halfWaveLineCutWidth = waveLineCutWidth / 2.0F
ccll_custom_view_area_provider_example_2.addCustomCutoutProvider { _, cutout, rectF ->
    cutout.moveTo(rectF.left, rectF.centerY() - halfWaveLineCutWidth)
    cutout.lineTo(rectF.left + rectF.width() / 4.0F, rectF.centerY() - halfWaveLineCutWidth - halfWaveLineHeight)
    cutout.lineTo(rectF.right - rectF.width() / 4.0F, rectF.centerY() - halfWaveLineCutWidth + halfWaveLineHeight)
    cutout.lineTo(rectF.right, rectF.centerY() - halfWaveLineCutWidth)
    cutout.lineTo(rectF.right, rectF.centerY() + halfWaveLineCutWidth)
    cutout.lineTo(rectF.right - rectF.width() / 4.0F, rectF.centerY() + halfWaveLineCutWidth + halfWaveLineHeight)
    cutout.lineTo(rectF.left + rectF.width() / 4.0F, rectF.centerY() + halfWaveLineCutWidth - halfWaveLineHeight)
    cutout.lineTo(rectF.left, rectF.centerY() + halfWaveLineCutWidth)
    cutout.lineTo(rectF.left, rectF.centerY() - halfWaveLineCutWidth)
}

// 2. Set Custom View Area Provider
ccll_showcase_custom_view_area_provider_example_2.setCustomViewAreaProvider { view, path, _ ->
    view.forEach {
        tempPath.rewind()
        if (it is CornerCutLinearLayout) {
            tempPath.offset(-it.left.toFloat(), -it.top.toFloat())
            tempPath.addPath(it.viewAreaPath) // nested ccll visible area path
            tempPath.transform(it.matrix)
            tempPath.offset(it.left.toFloat(), it.top.toFloat())
        } else {
            tempRectF.set(it.left.toFloat(), it.top.toFloat(), it.right.toFloat(), it.bottom.toFloat())
            val childCornerRadius = min(tempRectF.width(), tempRectF.height()) / 6.0F
            tempPath.addRoundRect(tempRectF, childCornerRadius, childCornerRadius, Path.Direction.CW)
            tempPath.offset(-it.left.toFloat(), -it.top.toFloat())
            tempPath.transform(it.matrix)
            tempPath.offset(it.left.toFloat(), it.top.toFloat())
        }
        path.op(tempPath, Path.Op.UNION)
    }
}

Note that 3rd child is clipped virtually. So when its bound overlay another visible area bounds corners of 3rd child become visible.

As you see custom shadow are build correctly upon custom visible view area (including children cutouts and transformations) & global custom cutouts.

The result would be as follow:

When you nest CornerCutLinearLayout in another CornerCutLinearLayout and work with CustomViewAreaProvider it might be necessary to get current visible view area path. The copy of it could be obtained via CornerCutLinearLayout.viewAreaPath*. In similar manner widget's padded bounds could be obtained (CornerCutLinearLayout.paddedBounds).

* - custom shadow are build upon viewAreaPath.

Custom Divider Provider

Sometimes you might want to have some not trivial different dividers at different positions mixed with default dividers. In a such scenario, CustomDividerProvider might come handy.

Example 1.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    android:id="@+id/ccll_custom_divider_provider_example_1"
    app:ccll_child_side_cut_flag="none"
    app:ccll_corner_cut_flag="all"
    app:ccll_corner_cut_type="oval"
    app:ccll_custom_divider_show_flag="container_beginning|middle|container_end"
    app:ccll_should_use_max_allowed_corner_cut_depth_or_length_to_be_equal="true"
    app:ccll_should_use_max_allowed_corner_cut_size="true">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

Then we define globally divider paint:

ccll_custom_divider_provider_example_1.doOnNonNullSizeLayout {
    val pb = it.paddedBounds
    it.customDividerProviderPaint.shader = RadialGradient(
        pb.centerX(), pb.centerY(),
        hypot(pb.width() / 2.0F, pb.height() / 2.0F) * 0.8F,
        Color.BLACK, Color.WHITE,
        Shader.TileMode.CLAMP
    )
}

Lastly, we add CustomDividerProvider:

ccll_custom_divider_provider_example_1.setCustomDividerProvider { _, dividerPath, dividerPaint, showDividerFlag, dividerTypeIndex, rectF ->
    when (showDividerFlag) {
        CornerCutLinearLayout.CustomDividerShowFlag.CONTAINER_BEGINNING -> {
            dividerPaint.style = Paint.Style.STROKE
            dividerPaint.strokeWidth = triangleHeight
            dividerPaint.pathEffect = PathDashPathEffect(topDividerTrianglePath, triangleBaseWidth, 0.0F, PathDashPathEffect.Style.TRANSLATE)
            dividerPath.moveTo(rectF.left, rectF.top)
            dividerPath.lineTo(rectF.right, rectF.top)
        }

        CornerCutLinearLayout.CustomDividerShowFlag.MIDDLE -> {
            dividerPaint.style = Paint.Style.STROKE
            if (dividerTypeIndex == 0) {
                dividerPaint.strokeWidth = circleRadius
                dividerPaint.pathEffect = PathDashPathEffect(circleDotDividerPath, triangleBaseWidth, 0.0F, PathDashPathEffect.Style.TRANSLATE)
                dividerPath.moveTo(rectF.left, rectF.centerY())
                dividerPath.lineTo(rectF.right + triangleBaseWidth, rectF.centerY())
            } else {
                dividerPaint.strokeWidth = circleRadius
                dividerPaint.pathEffect = PathDashPathEffect(diamondDotDividerPath, triangleBaseWidth, 0.0F, PathDashPathEffect.Style.TRANSLATE)
                dividerPath.moveTo(rectF.left, rectF.centerY())
                dividerPath.lineTo(rectF.right + triangleBaseWidth, rectF.centerY())
            }
        }

        CornerCutLinearLayout.CustomDividerShowFlag.CONTAINER_END -> {
            dividerPaint.style = Paint.Style.STROKE
            dividerPaint.strokeWidth = triangleHeight
            dividerPaint.pathEffect = PathDashPathEffect(bottomDividerTrianglePath, triangleBaseWidth, 0.0F, PathDashPathEffect.Style.TRANSLATE)
            dividerPath.moveTo(rectF.left, rectF.top)
            dividerPath.lineTo(rectF.right, rectF.top)
        }
    }
    true // accept divider path
}

The result would be as follow:

Example 2. This example shows the combination of custom and default's dividers.

<io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout
    android:id="@+id/ccll_custom_divider_provider_example_2"
    app:ccll_child_corner_cut_type="oval_inverse"
    app:ccll_corner_cut_flag="all"
    app:ccll_custom_divider_color="@color/divider"
    app:ccll_custom_divider_dash_gap="@dimen/divider_dash_gap"
    app:ccll_custom_divider_dash_width="@dimen/divider_dash_width"
    app:ccll_custom_divider_height="@dimen/divider_height"
    app:ccll_custom_divider_line_cap="round"
    app:ccll_custom_divider_show_flag="middle"
    app:ccll_custom_shadow_color="@color/accent_secondary">
    ...
</io.devlight.xtreeivi.cornercutlinearlayout.CornerCutLinearLayout>

ccll_custom_divider_provider_example_2.setCustomDividerProvider { _, dividerPath, dividerPaint, showDividerFlag, dividerTypeIndex, rectF ->
    when (showDividerFlag) {
        CornerCutLinearLayout.CustomDividerShowFlag.MIDDLE -> {
            dividerPaint.style = Paint.Style.STROKE
            when (dividerTypeIndex) {
                0 -> {
                    dividerPaint.shader = RadialGradient(
                        rectF.centerX(), rectF.centerY(),
                        rectF.width() / 2.0F, Color.GREEN, Color.RED,
                        Shader.TileMode.MIRROR
                    )
                    dividerPaint.strokeWidth = circleRadius
                    dividerPaint.pathEffect = PathDashPathEffect(diamondDotDividerPath, triangleBaseWidth, 0.0F, PathDashPathEffect.Style.TRANSLATE)
                    dividerPath.moveTo(rectF.left, rectF.centerY())
                    dividerPath.lineTo(rectF.right + triangleBaseWidth, rectF.centerY())
                    return@setCustomDividerProvider true // accept divider and draw it
                }
                
                2 -> {
                    dividerPaint.shader = LinearGradient(
                        rectF.centerX(), rectF.centerY() - halfWaveHeight,
                        rectF.centerX(), rectF.centerY() + halfWaveHeight,
                        Color.BLUE, Color.YELLOW, Shader.TileMode.CLAMP
                    )
                    dividerPaint.strokeWidth = halfWaveHeight * 2.0F
                    dividerPaint.pathEffect = PathDashPathEffect( wavePath, halfWaveWidth * 2.0F, 0.0F, PathDashPathEffect.Style.TRANSLATE)
                    dividerPath.moveTo(rectF.left, rectF.centerY())
                    dividerPath.lineTo(rectF.right, rectF.centerY())
                    return@setCustomDividerProvider true // accept divider and draw it
                }
                
                else -> return@setCustomDividerProvider false // skip divider and draw default
            }
        }
    }
    false // skip divider and draw default
}

The result would be as follow:

Sample App

In order to take closer look over examples provided and library in general, please run the sample app.

Author

Created by Mykola Melnyk - @xtreeivi

Donation

I would appreciate if you "toss the coin to your faithful servant".
Details: 5432 5912 5316 4615 (MasterCard)

Company

Created by Mykola Melnyk - @xtreeivi

Here you can see open source works developed by Devlight LLC.
This and another works is an exclusive property of Devlight LLC.

If you want to use this library in applications which will be available on Google Play, please report us or author of the library about it.

Whether you're searching for a new partner or trusted team for creating your new great product we are always ready to start work with you.

You can contact us: info@devlight.io or opensource@devlight.io.
Thanks in advance.

Devlight LLC, 2020 devlight.io

License

Please see LICENSE

CornerCutLinearLayout

General

Additional

Blurb

CornerCutLinearLayout

Installation

Usage

Basics

Declaration in XML

Declaration in Code (Kotlin)

Corner Cut Anatomy

Corner Cut Types

Layout Parameters

Edge Child

Extra Child Corner Cut Properties

Depth & Length Offset

Rotation

Shadow

Custom Divider

Advanced

Corner Cut Provider

Child Corner Cut Provider

Custom Cutout Provider

Custom View Area Provider

Custom Divider Provider

Sample App

Author

Donation

Company

Created by Mykola Melnyk - @xtreeivi

License