problems with R - ANDROID

Question

when i create a layout called " main.xml ":

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:padding="10dip"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">
    <Button
        android:id="@+id/button"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/button" />

    <Spinner
        android:id="@+id/spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
    />
</LinearLayout>

---

when i go to the main to create a button " button = (Button) findViewById(R.id.button); " i have an error , i cant find the button in R.id and same for the spinner the id dont exist in R.id

help me plz

Answer 1

You're probably importing the wrong version of R. There are two versions which exist: the static R class which exists in android.R and then there is also yourPackageName.R. If you import the former none of your Ids will be found.

Answer 2

Make sure you don't have any files, pictures, etc in your drawable or assets folder with capital letters, spaces, or dashes. Just use plane old lowercase. Also, try to clean your project. Go to project > clean. Then restart eclipse. Hope this helps. Also eclipse won't reconize any changes in XML files without saving first. Make sure to save after you add a button, ect.

Answer 3

尝试验证XML文件中没有错误，而不是尝试清理项目。