在这个计算器中哪个布局应该替换 LinearLayout
Which layout should replace LinearLayout in this calculator
我已经使用 LinearLayout 实现了这个简单的计算器布局，但遇到了来自 Android Studio 的“嵌套权重”警告。
这是我第一次尝试为 android 做点什么，所以我开始阅读：TableLayout 和 GridLayout 会遇到同样的问题，据我所知，ConstraintLayout到处都推荐。
但我想不通，如何使用 ConstraintLayout 获得相同的结果。
可能吗？在这种情况下，放弃 LinearLayout 是否值得？
我的布局：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:paddingRight="0dp"
android:paddingTop="10dp"
android:orientation="vertical"
android:background="#F5F5F6"
>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:text="2 + 2"
android:textSize="30sp"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:text="4"
android:textSize="30sp"
android:textColor="#000"
android:gravity="right"
android:layout_marginRight="10dp"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal"
>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="3"
android:orientation="vertical"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num7"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="7"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num8"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="8"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num9"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="9"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num4"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="4"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num5"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="5"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num6"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="6"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num1"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="1"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num2"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="2"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num3"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="3"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num_dot"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="."
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num0"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="0"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_del"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="del"
style="@style/Operand"
/>
</LinearLayout>
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical"
android:background="#E1E2E1"
>
<Button
android:id="@+id/keyboard_division"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="÷"
style="@style/Operator"
/>
<Button
android:id="@+id/keyboard_multiplication"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="×"
/>
<Button
android:id="@+id/keyboard_minus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="−"
/>
<Button
android:id="@+id/keyboard_plus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="+"
/>
<Button
android:id="@+id/keyboard_equal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Equal"
android:text="="
/>
</LinearLayout>
</LinearLayout>
</LinearLayout>
好吧，回答我自己的问题“如何使用 ConstraintLayout 获得相同的结果”
我已经用ConstraintLayout把它弄平了，但仍然不知道这是否值得，以及当你可以使用任何布局时如何决定使用哪种布局。
并且使用带有 app:layout_constraintGuide_percent and/or chainStyle="spread_inside" 的准则，从性能的角度来看，大小为 0 比“嵌套权重”更好。
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.constraintlayout.widget.Guideline
android:id="@+id/guidelineH"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintGuide_percent="0.33"
android:orientation="horizontal"
/>
<androidx.constraintlayout.widget.Guideline
android:id="@+id/guidelineV"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintGuide_percent="0.75"
android:orientation="vertical"
/>
<TextView
android:id="@+id/formula"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="@id/result"
app:layout_constraintVertical_chainStyle="packed"
tools:text="2+2"
android:textSize="36sp"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<TextView
android:id="@+id/result"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="@id/formula"
app:layout_constraintBottom_toTopOf="@id/guidelineH"
app:layout_constraintVertical_chainStyle="packed"
tools:text="4"
android:textSize="30sp"
android:textColor="#000"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<Button
android:id="@+id/keyboard_num7"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num4"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num8"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="7"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num8"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num5"
app:layout_constraintLeft_toRightOf="@id/keyboard_num7"
app:layout_constraintRight_toLeftOf="@id/keyboard_num9"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="8"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num9"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num6"
app:layout_constraintLeft_toRightOf="@id/keyboard_num8"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="9"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num4"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num1"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num5"
app:layout_constraintTop_toBottomOf="@id/keyboard_num7"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="4"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num5"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num2"
app:layout_constraintLeft_toRightOf="@id/keyboard_num4"
app:layout_constraintRight_toLeftOf="@id/keyboard_num6"
app:layout_constraintTop_toBottomOf="@id/keyboard_num8"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="5"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num6"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num3"
app:layout_constraintLeft_toRightOf="@id/keyboard_num5"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num9"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="6"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num1"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num_dot"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num2"
app:layout_constraintTop_toBottomOf="@id/keyboard_num4"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="1"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num2"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num0"
app:layout_constraintLeft_toRightOf="@id/keyboard_num1"
app:layout_constraintRight_toLeftOf="@id/keyboard_num3"
app:layout_constraintTop_toBottomOf="@id/keyboard_num5"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="2"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num3"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num_del"
app:layout_constraintLeft_toRightOf="@id/keyboard_num2"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num6"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="3"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_dot"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num0"
app:layout_constraintTop_toBottomOf="@id/keyboard_num1"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="."
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num0"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toRightOf="@id/keyboard_num_dot"
app:layout_constraintRight_toLeftOf="@id/keyboard_num_del"
app:layout_constraintTop_toBottomOf="@id/keyboard_num2"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="0"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_del"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toRightOf="@id/keyboard_num0"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num3"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="del"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_division"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_multiplication"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="÷"
style="@style/Operator"
/>
<Button
android:id="@+id/keyboard_multiplication"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_minus"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_division"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="×"
/>
<Button
android:id="@+id/keyboard_minus"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_plus"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_multiplication"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="−"
/>
<Button
android:id="@+id/keyboard_plus"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_equal"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_minus"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="+"
/>
<Button
android:id="@+id/keyboard_equal"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintTop_toBottomOf="@id/keyboard_plus"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Equal"
android:text="="
/>
</androidx.constraintlayout.widget.ConstraintLayout>
我已经使用 LinearLayout 实现了这个简单的计算器布局，但遇到了来自 Android Studio 的“嵌套权重”警告。
这是我第一次尝试为 android 做点什么，所以我开始阅读：TableLayout 和 GridLayout 会遇到同样的问题，据我所知，ConstraintLayout到处都推荐。
但我想不通，如何使用 ConstraintLayout 获得相同的结果。
可能吗？在这种情况下，放弃 LinearLayout 是否值得？
我的布局：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:paddingRight="0dp"
android:paddingTop="10dp"
android:orientation="vertical"
android:background="#F5F5F6"
>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:text="2 + 2"
android:textSize="30sp"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:text="4"
android:textSize="30sp"
android:textColor="#000"
android:gravity="right"
android:layout_marginRight="10dp"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:orientation="horizontal"
>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="3"
android:orientation="vertical"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num7"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="7"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num8"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="8"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num9"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="9"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num4"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="4"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num5"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="5"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num6"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="6"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num1"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="1"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num2"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="2"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num3"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="3"
style="@style/Operand"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="@color/colorAccent"
android:orientation="horizontal"
>
<Button
android:id="@+id/keyboard_num_dot"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="."
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num0"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="0"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_del"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="1"
android:text="del"
style="@style/Operand"
/>
</LinearLayout>
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical"
android:background="#E1E2E1"
>
<Button
android:id="@+id/keyboard_division"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="÷"
style="@style/Operator"
/>
<Button
android:id="@+id/keyboard_multiplication"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="×"
/>
<Button
android:id="@+id/keyboard_minus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="−"
/>
<Button
android:id="@+id/keyboard_plus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Operator"
android:text="+"
/>
<Button
android:id="@+id/keyboard_equal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
style="@style/Equal"
android:text="="
/>
</LinearLayout>
</LinearLayout>
</LinearLayout>
好吧，回答我自己的问题“如何使用 ConstraintLayout 获得相同的结果”
我已经用ConstraintLayout把它弄平了，但仍然不知道这是否值得，以及当你可以使用任何布局时如何决定使用哪种布局。
并且使用带有 app:layout_constraintGuide_percent and/or chainStyle="spread_inside" 的准则，从性能的角度来看，大小为 0 比“嵌套权重”更好。
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.constraintlayout.widget.Guideline
android:id="@+id/guidelineH"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintGuide_percent="0.33"
android:orientation="horizontal"
/>
<androidx.constraintlayout.widget.Guideline
android:id="@+id/guidelineV"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintGuide_percent="0.75"
android:orientation="vertical"
/>
<TextView
android:id="@+id/formula"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="@id/result"
app:layout_constraintVertical_chainStyle="packed"
tools:text="2+2"
android:textSize="36sp"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<TextView
android:id="@+id/result"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="@id/formula"
app:layout_constraintBottom_toTopOf="@id/guidelineH"
app:layout_constraintVertical_chainStyle="packed"
tools:text="4"
android:textSize="30sp"
android:textColor="#000"
android:gravity="right"
android:layout_marginRight="10dp"
/>
<Button
android:id="@+id/keyboard_num7"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num4"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num8"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="7"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num8"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num5"
app:layout_constraintLeft_toRightOf="@id/keyboard_num7"
app:layout_constraintRight_toLeftOf="@id/keyboard_num9"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="8"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num9"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num6"
app:layout_constraintLeft_toRightOf="@id/keyboard_num8"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="9"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num4"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num1"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num5"
app:layout_constraintTop_toBottomOf="@id/keyboard_num7"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="4"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num5"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num2"
app:layout_constraintLeft_toRightOf="@id/keyboard_num4"
app:layout_constraintRight_toLeftOf="@id/keyboard_num6"
app:layout_constraintTop_toBottomOf="@id/keyboard_num8"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="5"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num6"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num3"
app:layout_constraintLeft_toRightOf="@id/keyboard_num5"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num9"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="6"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num1"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num_dot"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num2"
app:layout_constraintTop_toBottomOf="@id/keyboard_num4"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="1"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num2"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num0"
app:layout_constraintLeft_toRightOf="@id/keyboard_num1"
app:layout_constraintRight_toLeftOf="@id/keyboard_num3"
app:layout_constraintTop_toBottomOf="@id/keyboard_num5"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="2"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num3"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_num_del"
app:layout_constraintLeft_toRightOf="@id/keyboard_num2"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num6"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="3"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_dot"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toLeftOf="@id/keyboard_num0"
app:layout_constraintTop_toBottomOf="@id/keyboard_num1"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="."
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num0"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toRightOf="@id/keyboard_num_dot"
app:layout_constraintRight_toLeftOf="@id/keyboard_num_del"
app:layout_constraintTop_toBottomOf="@id/keyboard_num2"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="0"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_num_del"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toRightOf="@id/keyboard_num0"
app:layout_constraintRight_toLeftOf="@id/guidelineV"
app:layout_constraintTop_toBottomOf="@id/keyboard_num3"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="del"
style="@style/Operand"
/>
<Button
android:id="@+id/keyboard_division"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_multiplication"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/guidelineH"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
android:text="÷"
style="@style/Operator"
/>
<Button
android:id="@+id/keyboard_multiplication"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_minus"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_division"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="×"
/>
<Button
android:id="@+id/keyboard_minus"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_plus"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_multiplication"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="−"
/>
<Button
android:id="@+id/keyboard_plus"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@id/keyboard_equal"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="@id/keyboard_minus"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Operator"
android:text="+"
/>
<Button
android:id="@+id/keyboard_equal"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintTop_toBottomOf="@id/keyboard_plus"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toRightOf="@id/guidelineV"
app:layout_constraintHorizontal_chainStyle="spread_inside"
app:layout_constraintVertical_chainStyle="spread_inside"
style="@style/Equal"
android:text="="
/>
</androidx.constraintlayout.widget.ConstraintLayout>