Exception is : Failed to Compile Values file. & <item> inner element must either be a resource reference or empty

Question

i'm trying to solve this error but that is stoping me for compiling my project so anyone have to solve this error. ** > Task :app:mergeDebugResources FAILED Execution failed for task ':app:mergeDebugResources'.

A failure occurred while executing com.android.build.gradle.internal.res.ResourceCompilerRunnable Resource compilation failed. Check logs for details.** i tried to clean & rebuild project. i also tried with cache & clear project.

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <attr format="enum" name="animateCircleAngleTo">
        <enum name="bestChoice" value="0"/>
        <enum name="closest" value="1"/>
        <enum name="clockwise" value="2"/>
        <enum name="antiClockwise" value="3"/>
        <enum name="constraint" value="4"/>
    </attr>
    <attr format="reference" name="animateRelativeTo"/>
    <attr format="enum" name="arcMode">
        <enum name="startVertical" value="0"/>
        <enum name="startHorizontal" value="1"/>
        <enum name="flip" value="2"/>
    </attr>
    <attr format="boolean" name="barrierAllowsGoneWidgets"/>
    <attr format="enum" name="barrierDirection">
        <enum name="left" value="0"/>
        <enum name="right" value="1"/>
        <enum name="top" value="2"/>
        <enum name="bottom" value="3"/>
        <enum name="start" value="5"/>
        <enum name="end" value="6"/>
    </attr>
    <attr format="dimension" name="barrierMargin"/>
    <attr format="dimension" name="borderRound"/>
    <attr format="float" name="borderRoundPercent"/>
    <attr format="boolean" name="chainUseRtl"/>
    <attr format="dimension" name="circleRadius"/>
    <attr format="string" name="circularflow_angles"/>
    <attr format="float" name="circularflow_defaultAngle"/>
    <attr format="dimension" name="circularflow_defaultRadius"/>
    <attr format="string" name="circularflow_radiusInDP"/>
    <attr format="reference" name="circularflow_viewCenter"/>
    <attr format="reference" name="constraintSet"/>
    <attr format="string" name="constraint_referenced_ids"/>
    <attr format="string" name="constraint_referenced_tags"/>
    <attr format="reference" name="content"/>
    <attr format="enum" name="curveFit">
        <enum name="spline" value="0"/>
        <enum name="linear" value="1"/>
    </attr>
    <attr format="integer" name="defaultDuration"/>
    <attr format="float" name="deltaPolarAngle"/>
    <attr format="float" name="deltaPolarRadius"/>
    <attr format="enum" name="dragDirection">
        <enum name="dragUp" value="0"/>
        <enum name="dragDown" value="1"/>
        <enum name="dragLeft" value="2"/>
        <enum name="dragRight" value="3"/>
        <enum name="dragStart" value="4"/>
        <enum name="dragEnd" value="5"/>
        <enum name="dragClockwise" value="6"/>
        <enum name="dragAnticlockwise" value="7"/>
    </attr>
    <attr format="enum" name="drawPath">
        <enum name="none" value="0"/>
        <enum name="path" value="1"/>
        <enum name="pathRelative" value="2"/>
        <enum name="deltaRelative" value="3"/>
        <enum name="asConfigured" value="4"/>
        <enum name="rectangles" value="5"/>
    </attr>
    <attr format="integer" name="duration"/>
    <attr format="float" name="flow_firstHorizontalBias"/>
    <attr format="enum" name="flow_firstHorizontalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="float" name="flow_firstVerticalBias"/>
    <attr format="enum" name="flow_firstVerticalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="enum" name="flow_horizontalAlign">
        <enum name="start" value="0"/>
        <enum name="end" value="1"/>
        <enum name="center" value="2"/>
    </attr>
    <attr format="float" name="flow_horizontalBias"/>
    <attr format="dimension" name="flow_horizontalGap"/>
    <attr format="enum" name="flow_horizontalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="float" name="flow_lastHorizontalBias"/>
    <attr format="enum" name="flow_lastHorizontalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="float" name="flow_lastVerticalBias"/>
    <attr format="enum" name="flow_lastVerticalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="integer" name="flow_maxElementsWrap"/>
    <attr format="dimension" name="flow_padding"/>
    <attr format="enum" name="flow_verticalAlign">
        <enum name="top" value="0"/>
        <enum name="bottom" value="1"/>
        <enum name="center" value="2"/>
        <enum name="baseline" value="3"/>
    </attr>
    <attr format="float" name="flow_verticalBias"/>
    <attr format="dimension" name="flow_verticalGap"/>
    <attr format="enum" name="flow_verticalStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="enum" name="flow_wrapMode">
        <enum name="none" value="0"/>
        <enum name="chain" value="1"/>
        <enum name="aligned" value="2"/>
        <enum name="chain2" value="3"/>
    </attr>
    <attr format="integer" name="framePosition"/>
    <attr format="boolean" name="guidelineUseRtl"/>
    <attr format="reference" name="layoutDescription"/>
    <attr format="enum" name="layoutDuringTransition">
        <enum name="ignoreRequest" value="0"/>
        <enum name="honorRequest" value="1"/>
        <enum name="callMeasure" value="2"/>

    </attr>
    <attr format="boolean" name="layout_constrainedHeight"/>
    <attr format="boolean" name="layout_constrainedWidth"/>
    <attr format="integer" name="layout_constraintBaseline_creator"/>
    <attr format="reference|enum" name="layout_constraintBaseline_toBaselineOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintBaseline_toBottomOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintBaseline_toTopOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="integer" name="layout_constraintBottom_creator"/>
    <attr format="reference|enum" name="layout_constraintBottom_toBottomOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintBottom_toTopOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference" name="layout_constraintCircle"/>
    <attr format="float" name="layout_constraintCircleAngle"/>
    <attr format="dimension" name="layout_constraintCircleRadius"/>
    <attr format="string" name="layout_constraintDimensionRatio"/>
    <attr format="reference|enum" name="layout_constraintEnd_toEndOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintEnd_toStartOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="dimension" name="layout_constraintGuide_begin"/>
    <attr format="dimension" name="layout_constraintGuide_end"/>
    <attr format="float" name="layout_constraintGuide_percent"/>
    <attr format="dimension|enum|string" name="layout_constraintHeight">
        <enum name="match_parent" value="-1"/>
        <enum name="wrap_content" value="-2"/>
        <enum name="match_constraint" value="-3"/>
        <enum name="wrap_content_constrained" value="-4"/>
    </attr>
    <attr name="layout_constraintHeight_default">
        <enum name="spread" value="0"/>
        <enum name="wrap" value="1"/>
        <enum name="percent" value="2"/>
    </attr>
    <attr format="dimension|enum" name="layout_constraintHeight_max">
        <enum name="wrap" value="-2"/>
    </attr>
    <attr format="dimension|enum" name="layout_constraintHeight_min">
        <enum name="wrap" value="-2"/>
    </attr>
    <attr format="float" name="layout_constraintHeight_percent"/>
    <attr format="float" name="layout_constraintHorizontal_bias"/>
    <attr format="enum" name="layout_constraintHorizontal_chainStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="float" name="layout_constraintHorizontal_weight"/>
    <attr format="integer" name="layout_constraintLeft_creator"/>
    <attr format="reference|enum" name="layout_constraintLeft_toLeftOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintLeft_toRightOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="integer" name="layout_constraintRight_creator"/>
    <attr format="reference|enum" name="layout_constraintRight_toLeftOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintRight_toRightOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintStart_toEndOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintStart_toStartOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="string" name="layout_constraintTag"/>
    <attr format="integer" name="layout_constraintTop_creator"/>
    <attr format="reference|enum" name="layout_constraintTop_toBottomOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="reference|enum" name="layout_constraintTop_toTopOf">
        <enum name="parent" value="0"/>
    </attr>
    <attr format="float" name="layout_constraintVertical_bias"/>
    <attr format="enum" name="layout_constraintVertical_chainStyle">
        <enum name="spread" value="0"/>
        <enum name="spread_inside" value="1"/>
        <enum name="packed" value="2"/>
    </attr>
    <attr format="float" name="layout_constraintVertical_weight"/>
    <attr format="dimension|enum|string" name="layout_constraintWidth">
        <enum name="match_parent" value="-1"/>
        <enum name="wrap_content" value="-2"/>
        <enum name="match_constraint" value="-3"/>
        <enum name="wrap_content_constrained" value="-4"/>
    </attr>
    <attr name="layout_constraintWidth_default">
        <enum name="spread" value="0"/>
        <enum name="wrap" value="1"/>
        <enum name="percent" value="2"/>
    </attr>
    <attr format="dimension|enum" name="layout_constraintWidth_max">
        <enum name="wrap" value="-2"/>
    </attr>
    <attr format="dimension|enum" name="layout_constraintWidth_min">
        <enum name="wrap" value="-2"/>
    </attr>
    <attr format="float" name="layout_constraintWidth_percent"/>
    <attr format="dimension" name="layout_editor_absoluteX"/>
    <attr format="dimension" name="layout_editor_absoluteY"/>
    <attr format="dimension" name="layout_goneMarginBaseline"/>
    <attr format="dimension" name="layout_goneMarginBottom"/>
    <attr format="dimension" name="layout_goneMarginEnd"/>
    <attr format="dimension" name="layout_goneMarginLeft"/>
    <attr format="dimension" name="layout_goneMarginRight"/>
    <attr format="dimension" name="layout_goneMarginStart"/>
    <attr format="dimension" name="layout_goneMarginTop"/>
    <attr format="dimension" name="layout_marginBaseline"/>
    <attr name="layout_optimizationLevel">
        <flag name="none" value="0"/>
        <flag name="legacy" value="0"/>
        <flag name="standard" value="257"/> <!-- direct, measure caches -->
        <flag name="direct" value="1"/>
        <flag name="barrier" value="2"/>
        <flag name="chains" value="4"/>
        <flag name="dimensions" value="8"/>
        <flag name="ratio" value="16"/>
        <flag name="groups" value="32"/>
        <flag name="graph" value="64"/>
        <flag name="graph_wrap" value="128"/>
        <flag name="cache_measures" value="256"/>
        <flag name="dependency_ordering" value="512"/>
        <flag name="grouping" value="1024"/>
    </attr>
    <attr format="enum" name="layout_wrapBehaviorInParent">
        <enum name="included" value="0"/>
        <enum name="horizontal_only" value="1"/>
        <enum name="vertical_only" value="2"/>
        <enum name="skipped" value="3"/>
    </attr>
    <attr format="float" name="motionPathRotate"/>
    <attr format="float" name="motionProgress"/>
    <attr format="float" name="motionStagger"/>
    <attr format="reference|string" name="motionTarget"/>
    <attr format="enum" name="onStateTransition">
        <enum name="actionDown" value="1"/>
        <enum name="actionUp" value="2"/>
        <enum name="actionDownUp" value="3"/>
        <enum name="sharedValueSet" value="4"/>
        <enum name="sharedValueUnset" value="5"/>
    </attr>
    <attr format="enum" name="pathMotionArc">
        <enum name="none" value="0"/>
        <enum name="startVertical" value="1"/>
        <enum name="startHorizontal" value="2"/>
        <enum name="flip" value="3"/>
    </attr>
    <attr format="float" name="path_percent"/>
    <attr format="float" name="perpendicularPath_percent"/>
    <attr format="reference|enum" name="pivotAnchor">
        <enum name="parent" value="0"/>
    </attr>
    <attr name="placeholder_emptyVisibility">
        <enum name="visible" value="0"/>
        <enum name="invisible" value="4"/>
        <enum name="gone" value="8"/>
    </attr>
    <attr format="reference" name="polarRelativeTo"/>
    <attr format="string|reference|enum" name="quantizeMotionInterpolator">
        <enum name="easeInOut" value="0"/>
        <enum name="easeIn" value="1"/>
        <enum name="easeOut" value="2"/>
        <enum name="linear" value="3"/>
        <enum name="bounce" value="4"/>
        <enum name="overshoot" value="5"/>
    </attr>
    <attr format="float" name="quantizeMotionPhase"/>
    <attr format="integer" name="quantizeMotionSteps"/>
    <attr format="float" name="sizePercent"/>
    <attr format="reference" name="targetId"/>
    <attr format="color" name="textOutlineColor"/>
    <attr format="dimension" name="textOutlineThickness"/>
    <attr format="reference" name="touchAnchorId"/>
    <attr format="enum" name="touchAnchorSide">
        <enum name="top" value="0"/>
        <enum name="left" value="1"/>
        <enum name="right" value="2"/>
        <enum name="bottom" value="3"/>
        <enum name="middle" value="4"/>
        <enum name="start" value="5"/>
        <enum name="end" value="6"/>
    </attr>
    <attr format="reference" name="transformPivotTarget"/>
    <attr format="boolean" name="transitionDisable"/>
    <attr format="string|enum" name="transitionEasing">
        <enum name="standard" value="0"/>
        <enum name="accelerate" value="1"/>
        <enum name="decelerate" value="2"/>
        <enum name="linear" value="3"/>
    </attr>
    <attr format="float" name="transitionPathRotate"/>
    <attr format="enum" name="viewTransitionMode">
        <enum name="currentState" value="0"/>
        <enum name="allStates" value="1"/>
        <!--        Operates independently of the rest of MotionLayout constraint set system -->
        <enum name="noState" value="2"/>
    </attr>
    <attr format="enum" name="visibilityMode">
        <enum name="normal" value="0"/>
        <enum name="ignore" value="1"/>
    </attr>
    <attr format="integer" name="waveDecay"/>
    <attr format="float|dimension" name="waveOffset"/>
    <attr format="float" name="wavePeriod"/>
    <attr format="float" name="wavePhase"/>
    <attr format="enum|string" name="waveShape">
        <enum name="sin" value="0"/>
        <enum name="square" value="1"/>
        <enum name="triangle" value="2"/>
        <enum name="sawtooth" value="3"/>
        <enum name="reverseSawtooth" value="4"/>
        <enum name="cos" value="5"/>
        <enum name="bounce" value="6"/>
    </attr>
    <attr format="enum" name="waveVariesBy">
        <enum name="position" value="0"/>
        <enum name="path" value="1"/>
    </attr><!-- This line is giving me a error like<item> inner element must either be a resource reference or empty>

</resources>