无法访问 GUI 上的对象 [重复]

Question

可能重复：
Developing for Android in Eclipse: R.java not generating

从 R.id.* 我可以访问 txtWeight、txtLength、lblWeight 和 lblLength，仅此而已。 Java 代码无法访问所有其他对象。

TextView lblAverage = (TextView) findViewById (R.id.lblAverage);

lblAverage cannot be resolved or is not a field

这是整个布局文件；

<RelativeLayout 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:padding="4dp" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="100dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:src="@drawable/fts  logo" />

    <TextView
        android:id="@+id/lblWeight"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/imageView1"
        android:layout_below="@+id/imageView1"
        android:layout_marginTop="21dp"
        android:text="Weight:"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <EditText
        android:id="@+id/txtWeight"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/lblWeight"
        android:layout_alignBottom="@+id/lblWeight"
        android:layout_alignParentRight="true"
        android:ems="10"
        android:inputType="numberDecimal" />

    <TextView
        android:id="@+id/lblLength"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/lblWeight"
        android:layout_below="@+id/txtWeight"
        android:layout_marginTop="24dp"
        android:text="Length:"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <EditText
        android:id="@+id/txtLength"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/lblLength"
        android:layout_alignBottom="@+id/lblLength"
        android:layout_alignLeft="@+id/txtWeight"
        android:ems="10"
        android:inputType="numberDecimal" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/lblLength"
        android:layout_centerHorizontal="true"
        android:ellipsize="none"
        android:paddingTop="16dp"
        android:text="Weight in kilograms, length in meters" />

    <Button
        android:id="@+id/btnCalculate"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="16dp"
        android:paddingLeft="24dp"
        android:paddingRight="24dp"
        android:text="Calculate"
        android:onClick="btnCalculate_clicked" />

    <TextView
        android:id="@+id/lblBMI"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/btnCalculate"
        android:layout_centerHorizontal="true"
        android:text="Your BMI is"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:visibility="invisible" />

    <TextView
        android:id="@+id/lblComparedToIndex"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/lblBMI"
        android:layout_below="@+id/lblBMI"
        android:layout_marginTop="14dp"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:visibility="invisible" />

    <Button
        android:id="@+id/btnSubmitToIndex"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/lblComparedToIndex"
        android:layout_centerHorizontal="true"
        android:text="Submit to index"
        android:visibility="invisible"
        android:onClick="btnSubmitToIndex_clicked" />

    <TextView
        android:id="@+id/lblAverage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="Average BMI: ?"
        android:textAppearance="?android:attr/textAppearanceMedium" />

</RelativeLayout>

Answer 1

I think R.java is not compiled correctly.
Try cleaning your project and import id for your application package once again.
I hope it will work