I have a custom header with a custom behavior that interacting with a coordinator layout. This header depends on an appBarLayout that contains a collapsingToolbarLayout and a Toolbar. When the toolbar layout collapses, the custom header adjust its properties and position the way I want, but the second I reach the min height of the layout, the appBarLayout overlaps the custom header and I can't see it until I begin expanding it.
This is the code for the layout:
<?xml version="1.0" encoding="utf-8"?><android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="@+id/toolbar_layout"
android:layout_width="match_parent"
android:layout_height="@dimen/mk_appbar_height">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/toolbar_collapse"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minHeight="@dimen/mt_toolbar_height"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:titleEnabled="false">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
style="@style/ToolbarStyle"
android:layout_width="match_parent"
android:layout_height="@dimen/mt_toolbar_height"
app:layout_collapseMode="pin"
/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<!-- This is a layout intended for containing MonkeyChatFragment and/or MonkeyConversationsFragment
RelativeLayout has an issue that doesn't render the RecyclerView with the whole size of its
container linear layout.
The only viable solution is FrameLayout -->
<FrameLayout
android:id="@+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"/>
<FrameLayout
android:id="@+id/viewStatus"
android:layout_width="match_parent"
android:layout_height="@dimen/status_height"
android:layout_marginTop="@dimen/status_inverse_height"
android:background="@color/mk_status_connected"/>
<com.criptext.monkeykitui.toolbar.HeaderView
android:id="@+id/custom_toolbar"
layout="@layout/custom_toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="56dp"
app:layout_behavior="com.criptext.monkeykitui.toolbar.HeaderViewBehavior"
app:behavior_overlapTop="64dp"
/></android.support.design.widget.CoordinatorLayout>
and this is the code of the layout_behavior:
class HeaderViewBehavior(context: Context, attrs: AttributeSet? = null) : CoordinatorLayout.Behavior<HeaderView>(context, attrs){
private val MIN_AVATAR_PERCENTAGE_SIZE = 0.3f
private val EXTRA_FINAL_AVATAR_PADDING = 80
private val TAG = "behavior"
private val mContext: Context = context
private val mCustomFinalHeight: Float = 0.toFloat()
private var mStartToolbarPosition: Float = 0.toFloat()
private var mStartYPosition: Int = 0
private var mFinalYPosition: Int = 0
private var mStartHeight: Int = 0
private var mfontSize: Float = 20.toFloat()
private var mChangeBehaviorPoint: Float = 0.toFloat()
override fun layoutDependsOn(parent: CoordinatorLayout?, child: HeaderView?, dependency: View?): Boolean {
var hello = (dependency is AppBarLayout)
return hello
}
override fun onDependentViewChanged(parent: CoordinatorLayout, child: HeaderView, dependency: View): Boolean {
maybeInitProperties(child, dependency)
val maxScrollDistance = - mContext.resources.getDimension(R.dimen.mk_header_scroll)
val expandedPercentageFactor = dependency.y / maxScrollDistance
Log.d("TEST", dependency.y.toString())
Log.d("TEST", maxScrollDistance.toString())
if (expandedPercentageFactor < mChangeBehaviorPoint) {
val heightFactor = (mChangeBehaviorPoint - expandedPercentageFactor) / mChangeBehaviorPoint
val distanceYToSubtract = (mStartYPosition - mFinalYPosition) * (1f - expandedPercentageFactor) + child.getHeight() / 2
child.setY(mStartYPosition - distanceYToSubtract)
val heightToSubtract = (mStartHeight - mCustomFinalHeight) * heightFactor
val lp = child.layoutParams as CoordinatorLayout.LayoutParams
child.layoutParams = lp
} else {
val distanceYToSubtract = (mStartYPosition - mFinalYPosition) * (1f - expandedPercentageFactor)
child.setY(mStartYPosition - distanceYToSubtract)
if(mStartYPosition - distanceYToSubtract < mStartYPosition){
child.setY(mStartYPosition.toFloat())
}else if(mStartYPosition - distanceYToSubtract > mFinalYPosition){
child.setY(mFinalYPosition.toFloat())
}
child.title.textSize = mfontSize - (mfontSize - 25) * (1f - expandedPercentageFactor)
child.subtitle.textSize = 15 - (15 - 20) * (1f - expandedPercentageFactor)
child.imageView.layoutParams.height = (126 - (126 - 226) * (1f - expandedPercentageFactor)).toInt()
child.imageView.layoutParams.width = (126 - (126 - 226) * (1f - expandedPercentageFactor)).toInt()
}
return true
}
private fun maybeInitProperties(child: HeaderView, dependency: View) {
if (mStartYPosition === 0)
mStartYPosition = 0
if (mFinalYPosition === 0)
mFinalYPosition = mContext.resources.getDimension(R.dimen.mk_header_scroll).toInt()
if (mStartHeight === 0)
mStartHeight = child.getHeight()
if (mStartToolbarPosition === 0.toFloat())
mStartToolbarPosition = dependency.y
if (mChangeBehaviorPoint === 0.toFloat())
mChangeBehaviorPoint = (child.height - mCustomFinalHeight) / (2f * (mStartYPosition - mFinalYPosition))
}
}