我一直收到此错误，导致我的应用崩溃。尝试实现新的v4滑动刷新布局。我更新了支持库+ sdk。有什么问题？
无法找到类'android.support.v4.widget.SwipeRefreshLayout'，引自方法...... onCreate
import android.support.v4.widget.SwipeRefreshLayout;
...
private SwipeRefreshLayout swipeLayout;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home_page_list);
swipeLayout = (SwipeRefreshLayout) findViewById(R.id.container);
swipeLayout.setColorScheme(android.R.color.holo_blue_bright,
android.R.color.holo_green_light,
android.R.color.holo_orange_light,
android.R.color.holo_red_light);
swipeLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
swipeLayout.setRefreshing(false);
}
});
XML
<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.devrim.ythaber.HomeActivity"
tools:ignore="MergeRootFrame" >
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<ImageView
android:id="@+id/thumb"
android:layout_width="100dp"
android:layout_height="100dp"
android:contentDescription="@string/app_name" />
<RelativeLayout
android:id="@+id/relativeLayout1"
android:layout_width="wrap_content"
android:layout_height="290dp"
android:layout_centerVertical="true"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:orientation="vertical" >
<!-- android:layout_toRightOf="@+id/thumb" -->
</RelativeLayout>
<TextView
android:id="@+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:ellipsize="end"
android:fontFamily="sans-serif-light"
android:maxLines="2"
android:shadowColor="@color/dropshadow"
android:shadowDx="2"
android:shadowDy="2"
android:shadowRadius="2"
android:text="@string/title"
android:textAllCaps="false"
android:textAppearance="?android:attr/textAppearanceSmallPopupMenu"
android:textColor="@color/titlecolour"
android:textSize="35sp"
android:textStyle="italic"
android:typeface="sans" >
</TextView>
<TextView
android:id="@+id/category"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/title"
android:ellipsize="end"
android:fontFamily="sans-serif-light"
android:gravity="right"
android:maxLines="1"
android:paddingRight="5dp"
android:paddingTop="10dp"
android:textAppearance="?android:attr/textAppearanceSmallPopupMenu"
android:textColor="@color/catcolour"
android:textSize="17sp"
android:textStyle="italic"
android:typeface="sans" >
</TextView>
</LinearLayout>
</ScrollView>
</android.support.v4.widget.SwipeRefreshLayout>
完成logcat：
05-01 21:31:27.390: W/dalvikvm(11452): VFY: unable to find class referenced in signature (Landroid/support/v4/widget/SwipeRefreshLayout;)
05-01 21:31:27.390: E/dalvikvm(11452): Could not find class 'android.support.v4.widget.SwipeRefreshLayout', referenced from method com.devrim.ythaber.HomeActivity.onCreate
05-01 21:31:27.390: W/dalvikvm(11452): VFY: unable to resolve check-cast 619 (Landroid/support/v4/widget/SwipeRefreshLayout;) in Lcom/devrim/ythaber/HomeActivity;
05-01 21:31:27.390: W/dalvikvm(11452): Link of class 'Lcom/devrim/ythaber/HomeActivity$1;' failed
05-01 21:31:27.440: W/dalvikvm(11452): threadid=1: thread exiting with uncaught exception (group=0x4166ee18)
05-01 21:31:27.440: E/AndroidRuntime(11452): FATAL EXCEPTION: main
05-01 21:31:27.440: E/AndroidRuntime(11452): Process: com.devrim.ythaber, PID: 11452
05-01 21:31:27.440: E/AndroidRuntime(11452): java.lang.NoClassDefFoundError: android.support.v4.widget.SwipeRefreshLayout
05-01 21:31:27.440: E/AndroidRuntime(11452): at com.devrim.ythaber.HomeActivity.onCreate(HomeActivity.java:56)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.Activity.performCreate(Activity.java:5312)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1111)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2552)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2653)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.ActivityThread.access$800(ActivityThread.java:156)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1355)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.os.Handler.dispatchMessage(Handler.java:102)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.os.Looper.loop(Looper.java:157)
05-01 21:31:27.440: E/AndroidRuntime(11452): at android.app.ActivityThread.main(ActivityThread.java:5872)
05-01 21:31:27.440: E/AndroidRuntime(11452): at java.lang.reflect.Method.invokeNative(Native Method)
05-01 21:31:27.440: E/AndroidRuntime(11452): at java.lang.reflect.Method.invoke(Method.java:515)
05-01 21:31:27.440: E/AndroidRuntime(11452): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1069)
05-01 21:31:27.440: E/AndroidRuntime(11452): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:885)
答案 0 :(得分：4)
如果您使用的是gradle，则可能需要检查是否已更新配置以使用19.1版本的android支持库。见以下一行：
dependencies {
compile 'com.android.support:support-v4:19.1.+'
}
答案 1 :(得分：3)
对我来说，问题是我的某个图书馆项目正在使用支持库的 v13 ：android-support-v13.jar。
请在日志中注意这样的消息：
Found both android-support-v4 and android-support-v13 in the dependency list.
Because v13 includes v4, using only v13.
如果您看到该警告，请确保您的库项目还包含最新的支持库，否则您的 v4 库可能会被旧的 v13 库取代（显然不包括新的SwipeRefreshLayout）。
答案 2 :(得分：0)
确认您的SDK管理器中安装的Android支持库是19.1而不仅仅是19。
如果是，并且您已尝试将项目更新到新库，我发现，这不能正常工作。创建一个空白的新Android应用程序项目，并将支持库从/ libs /复制到现有项目并再次尝试。