我使用 API 级别 8 开发了我的应用程序,但最低 SDK 为 3。我在运行 8 的模拟器和我的 DroidX 以及一些朋友的手机上进行了大部分测试。到目前为止没有问题。还应该知道,我没有使用任何高于 Level 3 的 API,并且 Tab Layout 几乎完全复制了 Google在此处提供的示例。所以......当在具有 5 级 API 的模拟器上运行时,我收到以下错误,除了对 TabWidget 的引用之外,我不知道它来自哪里。
Uncaught handler: thread main exiting due to uncaught exception
java.lang.NullPointerException
at android.widget.TabWidget.dispatchDraw(TabWidget.java:206)
at android.view.ViewGroup.drawChild(ViewGroup.java:1524)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256)
at android.view.ViewGroup.drawChild(ViewGroup.java:1524)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256)
at android.view.ViewGroup.drawChild(ViewGroup.java:1524)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256)
at android.view.View.draw(View.java:6539)
at android.widget.FrameLayout.draw(FrameLayout.java:352)
at android.view.ViewGroup.drawChild(ViewGroup.java:1526)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1256)
at android.view.View.draw(View.java:6539)
at android.widget.FrameLayout.draw(FrameLayout.java:352)
at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1830)
at android.view.ViewRoot.draw(ViewRoot.java:1348)
at android.view.ViewRoot.performTraversals(ViewRoot.java:1113)
at android.view.ViewRoot.handleMessage(ViewRoot.java:1632)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4310)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
at dalvik.system.NativeStart.main(Native Method)
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, parent.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("browse").setIndicator("Browse",
res.getDrawable(R.drawable.ic_tab_browse))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, bookmarks.class);
spec = tabHost.newTabSpec("bookmarks").setIndicator("Bookmarks",
res.getDrawable(R.drawable.ic_tab_bookmarks))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, search.class);
spec = tabHost.newTabSpec("search").setIndicator("Search",
res.getDrawable(R.drawable.ic_tab_search))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(0);