Android Studio 3.0.1新建应用报错：Can't convert to dimension: type=0x1

Hey there, that error usually pops up when your ConstraintLayout has invalid attribute values the system can’t interpret as valid dimensions. Let’s work through this together:

Common Causes & Step-by-Step Fixes #

1. Fix Truncated/Misconfigured ConstraintLayout Attributes #

Your XML code got cut off, but the most likely culprit is a messed-up ConstraintLayout-specific property. For example:

• If you wrote app:layout_constraintWidth_default="wrap" (invalid), replace it with app:layout_constraintWidth_default="wrap_content" (correct)
• If you set layout_constraintHeight_default to an unrecognized value, switch it to one of the valid options: "wrap_content", "match_parent", or "percent" (only if paired with layout_constraintHeight_percent for percentage sizing)

2. Verify Dimension Resources & Values #

Double-check all size-related properties (margins, padding, width/height) for valid formatting:

• Don’t use @string/ resources where @dimen/ is required (e.g., android:margin="@string/margin_16" is wrong; use @dimen/margin_16 instead)
• Always include units for hardcoded values (e.g., 16dp instead of just 16)

3. Reference a Valid ConstraintLayout Example #

Here’s a complete, error-free ConstraintLayout snippet to use as a guide:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 
    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">

    <TextView
        android:id="@+id/textView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_margin="16dp"/>

</android.support.constraint.ConstraintLayout>

4. Update ConstraintLayout Version (Optional but Recommended) #

Android Studio 3.0.1 works best with ConstraintLayout 1.1.x. Open your app-level build.gradle and ensure you’re using a stable version:

dependencies {
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
}

After making these changes, clean and rebuild your project (Build > Clean Project then Build > Rebuild Project) to apply fixes.

内容的提问来源于stack exchange，提问作者Ankon