Unable to start basic app due to error (UnsupportedOperationException: Can't convert to dimension: type=0x1)

Question

I am learning to create a CardView. I am able to see what the layout will look like in the design tab of Layout file and in the preview section of text section of Layout.

However, when I run the app on an emulator or android device it throws an error that says, "Unfortunately, CardActivity has stopped working."

I don't know what I'am doing wrong so please help.

This is the activity_main.xml file content.

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout 
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:card_view="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp">

        <!-- A CardView That contains a TextView -->
        <android.support.v7.widget.CardView 
            xmlns:card_view="http://schemas.android.com/apk/res-auto"
            android:id="@+id/card_view"
            android:layout_width="match_parent"
            card_view:cardUseCompatPadding="true"
            card_view:cardElevation="4dp"
            android:layout_height="wrap_content"
            card_view:cardCornerRadius="5dp"
            android:background="#dddddd">

            <LinearLayout
                android:layout_width="match_parent"
                android:orientation="vertical"
                android:layout_height="match_parent"
                android:weightSum="1"
                android:padding="10dp">

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:background="#4f76d2">

                    <ImageView
                        android:layout_width="50dp"
                        android:layout_height="50dp"
                        android:scaleType="centerCrop"
                        android:layout_margin="5dp"
                        android:src="@drawable/image" />

                    <TextView
                        android:id="@+id/info_text"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="@string/name"
                        android:textSize="?android:attr/textAppearanceLarge"
                        android:layout_margin="20dp"
                        android:textColor="#ffffff"
                        android:textIsSelectable="true" />

                </LinearLayout>

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="@string/para_text"
                    android:textSize="?android:attr/textAppearanceSmall"
                    android:textColor="#88b0f5"
                    android:padding="5dp" />

            </LinearLayout>

        </android.support.v7.widget.CardView>

    </LinearLayout>

This is the MainActivity.java file content.

package com.example.android.cardactivity;

import android.app.Activity;
import android.os.Bundle;

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

This is all that appears in the Android Monitor.

04-03 22:55:13.164 20095-20095/com.example.android.cardactivity E/AndroidRuntime: FATAL EXCEPTION: main
      Process: com.example.android.cardactivity, PID: 20095
      java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.cardactivity/com.example.android.cardactivity.MainActivity}: android.view.InflateException: Binary XML file line #41: Binary XML file line #41: Error inflating class android.widget.TextView
          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
          at android.app.ActivityThread.-wrap11(ActivityThread.java)
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
          at android.os.Handler.dispatchMessage(Handler.java:102)
          at android.os.Looper.loop(Looper.java:148)
          at android.app.ActivityThread.main(ActivityThread.java:5417)
          at java.lang.reflect.Method.invoke(Native Method)
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
       Caused by: android.view.InflateException: Binary XML file line #41: Binary XML file line #41: Error inflating class android.widget.TextView
          at android.view.LayoutInflater.inflate(LayoutInflater.java:539)
          at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
          at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
          at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:393)
          at android.app.Activity.setContentView(Activity.java:2166)
          at com.example.android.cardactivity.MainActivity.onCreate(MainActivity.java:10)
          at android.app.Activity.performCreate(Activity.java:6237)
          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
          at android.app.ActivityThread.-wrap11(ActivityThread.java) 
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
          at android.os.Handler.dispatchMessage(Handler.java:102) 
          at android.os.Looper.loop(Looper.java:148) 
          at android.app.ActivityThread.main(ActivityThread.java:5417) 
          at java.lang.reflect.Method.invoke(Native Method) 
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
       Caused by: android.view.InflateException: Binary XML file line #41: Error inflating class android.widget.TextView
          at android.view.LayoutInflater.createView(LayoutInflater.java:645)
          at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58)
          at android.view.LayoutInflater.onCreateView(LayoutInflater.java:694)
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:762)
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:835)
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838)
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838)
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838)
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
          at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
          at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
          at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:393) 
          at android.app.Activity.setContentView(Activity.java:2166) 
          at com.example.android.cardactivity.MainActivity.onCreate(MainActivity.java:10) 
          at android.app.Activity.performCreate(Activity.java:6237) 
          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107) 
          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369) 
          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
          at android.app.ActivityThread.-wrap11(ActivityThread.java) 
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
          at android.os.Handler.dispatchMessage(Handler.java:102) 
          at android.os.Looper.loop(Looper.java:148) 
          at android.app.ActivityThread.main(ActivityThread.java:5417) 
          at java.lang.reflect.Method.invoke(Native Method) 
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
       Caused by: java.lang.reflect.InvocationTargetException
          at java.lang.reflect.Constructor.newInstance(Native Method)
          at android.view.LayoutInflater.createView(LayoutInflater.java:619)
          at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58) 
          at android.view.LayoutInflater.onCreateView(LayoutInflater.java:694) 
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:762) 
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:835) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:515) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
          at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:393) 
          at android.app.Activity.setContentView(Activity.java:2166) 
          at com.example.android.cardactivity.MainActivity.onCreate(MainActivity.java:10) 
          at android.app.Activity.performCreate(Activity.java:6237) 
          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107) 
          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369) 
          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
          at android.app.ActivityThread.-wrap11(ActivityThread.java) 
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
          at android.os.Handler.dispatchMessage(Handler.java:102) 
          at android.os.Looper.loop(Looper.java:148) 
          at android.app.ActivityThread.main(ActivityThread.java:5417) 
          at java.lang.reflect.Method.invoke(Native Method) 
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
       Caused by: java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x1
          at android.content.res.TypedArray.getDimensionPixelSize(TypedArray.java:666)
          at android.widget.TextView.<init>(TextView.java:1055)
          at android.widget.TextView.<init>(TextView.java:671)
          at android.widget.TextView.<init>(TextView.java:667)
          at java.lang.reflect.Constructor.newInstance(Native Method) 
          at android.view.LayoutInflater.createView(LayoutInflater.java:619) 
          at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58) 
          at android.view.LayoutInflater.onCreateView(LayoutInflater.java:694) 
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:762) 
          at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:835) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.rInflate(LayoutInflater.java:838) 
          at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:515) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
          at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
          at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:393) 
          at android.app.Activity.setContentView(Activity.java:2166) 
          at com.example.android.cardactivity.MainActivity.onCreate(MainActivity.java:10) 
          at android.app.Activity.performCreate(Activity.java:6237) 
          at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107) 
          at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369) 
          at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
          at android.app.ActivityThread.-wrap11(ActivityThread.java) 
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
          at android.os.Handler.dispatchMessage(Handler.java:102) 
          at android.os.Looper.loop(Looper.java:148) 
          at android.app.ActivityThread.main(ActivityThread.java:5417) 
          at java.lang.reflect.Method.invoke(Native Method) 
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

May be your `Text View` is not getting a view. Which is your line no 10 in main activity ? — Jay Rathod, Apr 03 '16 at 17:41
@jaydroider can you please tell something more? or can you suggest required changed to code please if possible. thanks in advance :) — Ravi Kumar Seth, Apr 03 '16 at 17:43
@jaydroider line number 10 in main activity is setContentView(R.layout.activity_main); i have already added all contents of MainActivity.java class in the question — Ravi Kumar Seth, Apr 03 '16 at 17:45

George Mulligan · Accepted Answer · 2016-04-03T18:07:39.260

You are assigning the attribute android:textSize an invalid value of ?android:attr/textAppearanceLarge. You should instead assign the value to android:textAppearance as follows:

<TextView
    android:id="@+id/info_text"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/name"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:layout_margin="20dp"
    android:textColor="#ffffff"
    android:textIsSelectable="true" />

java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x1

The above is the key part of the exception that is found towards the bottom of the stack trace and can help you in figuring out the error.

Basically the attribute android:textSize expects a dimension for a value.

?android:attr/textAppearanceLarge is not a dimension value so the application crashes when trying to convert it into one.

@ARTofFeeding You're welcome. I added a little more detail as to how I found the error which might help you in the future. — George Mulligan, Apr 03 '16 at 18:08
@GeorgeMulligan thanks man :) hope to get help from people like you in future also :) — Ravi Kumar Seth, Apr 03 '16 at 18:11

Unable to start basic app due to error (UnsupportedOperationException: Can't convert to dimension: type=0x1)

1 Answers1