ANDROID Rendering problems NullException

android, android-layout, android-xml, xml

Solution

The children of a TableRow do not need to specify the layout_width and layout_height attributes in the XML file. TableRow always enforces those values to be respectively MATCH_PARENT and WRAP_CONTENT.

Try that:

<?xml version="1.0" encoding="utf-8"?>
<TableLayout 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:paddingLeft="@dimen/activity_horizontal_margin"
         android:paddingRight="@dimen/activity_horizontal_margin"
         android:paddingTop="@dimen/activity_vertical_margin"
         android:paddingBottom="@dimen/activity_vertical_margin"
         tools:context=".MainActivity"
         style="@style/activity_style">

<TableRow
    android:layout_height="0dp"
    android:layout_width="match_parent"
    android:layout_weight="2">
    <EditText
        style="@style/edit_text_timer"
        android:id="@+id/etHour"
        android:hint="@string/initial_value"
        android:layout_weight="3"
        android:layout_column="6"
        />

    <TextView
        android:id="@+id/tvColon"
        android:text="@string/colon_text_view"
        android:gravity="center"
        android:textColor="#e7ff00"
        android:textSize="30sp"
        android:layout_weight="1"/>

    <EditText
        style="@style/edit_text_timer"
        android:id="@+id/etMinute"
        android:hint="@string/initial_value"
        android:layout_weight="3"
        android:layout_column="13" />


    <TextView
        android:id="@id/tvColon"
        android:text="@string/colon_text_view"
        android:gravity="center"
        android:textColor="#e7ff00"
        android:textSize="30sp"
        android:layout_weight="1"
        android:layout_column="18" />

    <EditText
        style="@style/edit_text_timer"
        android:id="@+id/etSecond"
        android:hint="@string/initial_value"
        android:layout_weight="3"
        />
</TableRow>

<TableRow
    android:layout_height="0dp"
    android:layout_weight="1"
    android:layout_width="match_parent">
    <Button
        style="@style/button_text"
        android:id="@+id/button1"
        android:text="@string/button_1"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button2"
        android:text="@string/button_2"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button3"
        android:text="@string/button_3"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>

</TableRow>

<TableRow
    android:layout_height="0dp"
    android:layout_weight="1"
    android:layout_width="match_parent">
    <Button
        style="@style/button_text"
        android:id="@+id/button4"
        android:text="@string/button_4"
        android:layout_weight="1"
        android:onClick="buttonNumber"
        />
    <Button
        style="@style/button_text"
        android:id="@+id/button5"
        android:text="@string/button_5"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button6"
        android:text="@string/button_6"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>

</TableRow>

<TableRow
    android:layout_height="0dp"
    android:layout_weight="1"
    android:layout_width="match_parent">
    <Button
        style="@style/button_text"
        android:id="@+id/button7"
        android:text="@string/button_7"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button8"
        android:text="@string/button_8"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button9"
        android:text="@string/button_9"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
</TableRow>

<TableRow
    android:layout_weight="1"
    android:layout_height="0dp"
    android:layout_width="match_parent">
    <Button
        style="@style/button_text"
        android:id="@+id/emptyButton"
        android:text=""
        android:layout_weight="1"/>
    <Button
        style="@style/button_text"
        android:id="@+id/button0"
        android:text="@string/button_0"
        android:layout_weight="1"
        android:onClick="buttonNumber"/>
    <Button
        style="@style/button_text"
        android:id="@+id/buttonReset"
        android:text="@string/button_reset_text"
        android:layout_weight="1"/>

</TableRow>

<TableRow
    android:layout_weight="1"
    android:layout_height="0dp"
    android:layout_width="match_parent">
    <Button
        style="@style/button_text"
        android:layout_marginTop="10dp"
        android:id="@+id/startStopButton"
        android:text="@string/button_start"
        android:layout_weight="1"/>

    <Button
        style="@style/button_text"
        android:layout_marginTop="10dp"
        android:id="@+id/resetButton"
        android:text="@string/button_reset"
        android:layout_weight="1"/>

</TableRow>
</TableLayout>

Hope it helps!

Problem

I am a newbie in android programming. I tried to create a stopwatch application, but recently i got an error in the layout. I have been debugging this layout error for 2 days and still cannot find the solution. I do not think this is IDE problem because when i tested it using my phone, the program stopped(error). Please take a look of the error below: java.lang.NullPointerException at android.widget.LinearLayout.forceUniformHeight(LinearLayout.java:1380) at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1368) at android.widget.TableRow.onMeasure(TableRow.java:114) at android.view.View.measure(View.java:17430) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463) at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436) at android.widget.TableLayout.measureChildBeforeLayout(TableLayout.java:464) at android.widget.LinearLayout.measureVertical(LinearLayout.java:722) at android.widget.TableLayout.measureVertical(TableLayout.java:476) at android.widget.TableLayout.onMeasure(TableLayout.java:439) at android.view.View.measure(View.java:17430) at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463) at android.widget.FrameLayout.onMeasure(FrameLayout.java:430) at android.view.View.measure(View.java:17430) at android.widget.LinearLayout.measureVertical(LinearLayout.java:875) at android.widget.LinearLayout.onMeasure(LinearLayout.java:613) at android.view.View.measure(View.java:17430) at android.widget.LinearLayout.measureVertical(LinearLayout.java:875) at android.widget.LinearLayout.onMeasure(LinearLayout.java:613) at android.view.View.measure(View.java:17430) this is my code: ``` <?xml version="1.0" encoding="utf-8"?> <TableLayout 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:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity" style="@style/activity_style"> <TableRow android:layout_height="0dp" android:layout_width="match_parent" android:layout_weight="2"> <EditText style="@style/edit_text_timer" android:id="@+id/etHour" android:hint="@string/initial_value" android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="3" android:layout_column="6" /> <TextView android:id="@+id/tvColon" android:layout_height="match_parent" android:layout_width="0dp" android:text="@string/colon_text_view" android:gravity="center" android:textColor="#e7ff00" android:textSize="30sp" android:layout_weight="1"/> <EditText style="@style/edit_text_timer" android:id="@+id/etMinute" android:hint="@string/initial_value" android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="3" android:layout_column="13" /> <TextView android:id="@id/tvColon" android:layout_height="match_parent" android:layout_width="0dp" android:text="@string/colon_text_view" android:gravity="center" android:textColor="#e7ff00" android:textSize="30sp" android:layout_weight="1" android:layout_column="18" /> <EditText style="@style/edit_text_timer" android:id="@+id/etSecond" android:hint="@string/initial_value" android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="3" /> </TableRow> <TableRow android:layout_height="0dp" android:layout_weight="1" android:layout_width="match_parent"> <Button style="@style/button_text" android:id="@+id/button1" android:layout_width="0dp" android:text="@string/button_1" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/button2" android:layout_width="0dp" android:text="@string/button_2" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/button3" android:layout_width="0dp" android:text="@string/button_3" android:layout_weight="1" android:onClick="buttonNumber"/> </TableRow> <TableRow android:layout_height="0dp" android:layout_weight="1" android:layout_width="match_parent"> <Button style="@style/button_text" android:id="@+id/button4" android:layout_width="0dp" android:text="@string/button_4" android:layout_weight="1" android:onClick="buttonNumber" /> <Button style="@style/button_text" android:id="@+id/button5" android:layout_width="0dp" android:text="@string/button_5" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/button6" android:layout_width="0dp" android:text="@string/button_6" android:layout_weight="1" android:onClick="buttonNumber"/> </TableRow> <TableRow android:layout_height="0dp" android:layout_weight="1" android:layout_width="match_parent"> <Button style="@style/button_text" android:id="@+id/button7" android:layout_width="0dp" android:text="@string/button_7" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/button8" android:layout_width="0dp" android:text="@string/button_8" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/button9" android:layout_width="0dp" android:text="@string/button_9" android:layout_weight="1" android:onClick="buttonNumber"/> </TableRow> <TableRow android:layout_weight="1" android:layout_height="0dp" android:layout_width="match_parent"> <Button style="@style/button_text" android:id="@+id/emptyButton" android:layout_width="0dp" android:text="" android:layout_weight="1"/> <Button style="@style/button_text" android:id="@+id/button0" android:layout_width="0dp" android:text="@string/button_0" android:layout_weight="1" android:onClick="buttonNumber"/> <Button style="@style/button_text" android:id="@+id/buttonReset" android:layout_width="0dp" android:text="@string/button_reset_text" android:layout_weight="1"/> </TableRow> <TableRow android:layout_weight="1" android:layout_height="0dp" android:layout_width="match_parent"> <Button style="@style/button_text" android:layout_marginTop="10dp" android:id="@+id/startStopButton" android:layout_width="0dp" android:text="@string/button_start" android:layout_weight="1"/> <Button style="@style/button_text" android:layout_marginTop="10dp" android:id="@+id/resetButton" android:layout_width="0dp" android:text="@string/button_reset" android:layout_weight="1"/> </TableRow> </TableLayout> enter code here ```

Original source