Android矢量Drawable问题：首图形未生成、次图形无法占满宽度

Hey there! Let's work through those two vector drawable problems you're facing:

1. First Vector Drawable Not Generating at All #

This usually boils down to a syntax issue in your vector XML, compatibility settings, or a wrong reference. Here are the fixes to try:

• Check your vector XML for errors: Open the first vector drawable file in Android Studio—look for red underlines in the code (like missing closing tags, invalid path d values, or missing required attributes on the <vector> tag). Make sure the root <vector> has these mandatory attributes:

  <vector xmlns:android="http://schemas.android.com/apk/res/android"
      android:width="24dp"
      android:height="24dp"
      android:viewportWidth="24"
      android:viewportHeight="24">
      <!-- Your path/shape elements here -->
  </vector>
  

• Enable vector compatibility: If you're targeting Android versions older than API 21, add this to your app-level build.gradle to support vector drawables across devices:

  android {
      defaultConfig {
          vectorDrawables.useSupportLibrary = true
      }
  }
  

• Verify your drawable reference: Double-check that you're using the correct name in your layout (Android is case-sensitive!). For example, if your file is custom_shape_1.xml, make sure you're referencing @drawable/custom_shape_1 and not a typo like @drawable/Custom_Shape_1.

2. Second Vector Drawable Won't Fill the Full Width #

This is almost always a scaling or layout configuration issue. Try these steps:

• Adjust the vector's size attributes: In your second vector XML, set android:width="match_parent" and keep android:viewportWidth set to the original vector's intrinsic width (e.g., 24 for a 24x24 vector). This lets the drawable stretch to fit its container.
• Tweak your layout's View settings: If you're using an ImageView to display the drawable, update these attributes:

  <ImageView
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:src="@drawable/your_second_vector"
      android:scaleType="fitXY" <!-- Stretches to fill width/height, or use "fitStart" to keep aspect ratio while filling width -->
      android:adjustViewBounds="true" /> <!-- Helps maintain aspect ratio if needed -->
  

• Check your LinearLayout orientation: If your parent LinearLayout is set to android:orientation="horizontal", make sure the child view holding the vector has android:layout_weight="1" (if you want it to take available space) or android:layout_width="match_parent" (if it's the only child).

If you can share the full XML code for both vector drawables and your complete main.xml layout, we can pinpoint the exact issue even faster!

内容的提问来源于stack exchange，提问作者john