只有一个Activity,它使用带有3个选项卡的ActionBar。在TabListener中,我使用setContentView加载特定于该选项卡的布局,然后将相关片段添加到它们的框架中。这 几乎 与我想要的完全相同,除了当您快速切换选项卡时,应用程序会崩溃。
我正在使用三星Galaxy Tab作为我的调试设备,切换选项卡非常快。以正常的速度,我可以在它们之间来回轻敲,页面会立即加载。问题是当我在选项卡之间超级快速切换时。
起初我收到了一个
IllegalStateException: Fragment not added
如下所示: http://code.google.com/p/android/issues/detail?id=17029 按照在onTabUnselected中使用try/catch块的建议,我使应用程序更加健壮,但这导致了手头的问题:
IllegalArgumentException: No view found for id 0x... for fragment ...
我在网上没有找到任何其他人有相同的问题,所以我担心我可能在做一些不被支持的事情。 再次强调,我试图在一个Activity中使用3个不同的布局 - 当你点击选项卡时,监听器会调用setContentView来更改布局,然后添加片段。它工作得很好,除非你开始频繁地切换选项卡。
我从这里得到了灵感:http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/app/FragmentTabs.html 而我不是像TabListener那样保留对一个片段的引用,而是有一个数组。此外,我没有使用attach/detach,因为它们只在API 13中添加。
我的理论是,要么setContentView还没有完成创建视图,这就是为什么FragmentTransaction无法添加它们的原因,要么当选择另一个选项卡并调用setContentView时,片段正在为一个选项卡添加,破坏了另一组视图。
我尝试了一些方法来减缓选项卡切换,但没有进展。
这是我的TabListener代码:
private class BTabListener<T extends Fragment> implements ActionBar.TabListener{
private int mLayout;
private Fragment[] mFrags;
private TabData mTabData;
private Activity mAct;
private boolean mNoNewFrags;
public BTabListener(Activity act, int layout, TabData td, boolean frags){
mLayout = layout;
mTabData = td;
mAct = act;
mNoNewFrags = frags;
mFrags = new Fragment[mTabData.fragTags.length];
for(int i=0; i<mFrags.length; i++){
//on an orientation change, this will find the fragments that were recreated by the system
mFrags[i] = mAct.getFragmentManager().findFragmentByTag(mTabData.fragTags[i]);
}
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
//this gets called _after_ unselected
//note: unselected wont have been called after an orientation change!
//we also need to watch out because tab 0 always gets selected when adding the tabs
//set the view for this tab
mAct.setContentView(mLayout);
for(int i=0; i<mFrags.length; i++){
//this will be null when the tab is first selected
if(mFrags[i]==null ){
mFrags[i] = Fragment.instantiate(GUITablet.this, mTabData.classes[i].getName());
}
//if there was an orientation change when we were on this page, the fragment is already added
if(!mNoNewFrags || mDefaultTab!=tab.getPosition()){
ft.add(mTabData.containterIDs[i], mFrags[i], mTabData.fragTags[i]);
}
}
mNoNewFrags = false;
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
// this gets called when another tab is selected, before it's onSelected method
for(Fragment f : mFrags){
try{ //extra safety measure
ft.remove(f);
}catch(Exception e){
e.printStackTrace();
System.out.println("unselect couldnt remove");
}
}
}
}
最后,堆栈跟踪:
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): java.lang.IllegalArgumentException: No view found for id 0x7f0b0078 for fragment Fraggle{40ab2230 #2 id=0x7f0b0078 dummy2}
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:729)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:926)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.BackStackRecord.run(BackStackRecord.java:578)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1226)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.FragmentManagerImpl$1.run(FragmentManager.java:374)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.os.Handler.handleCallback(Handler.java:587)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.os.Handler.dispatchMessage(Handler.java:92)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.os.Looper.loop(Looper.java:132)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at android.app.ActivityThread.main(ActivityThread.java:4028)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at java.lang.reflect.Method.invokeNative(Native Method)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at java.lang.reflect.Method.invoke(Method.java:491)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
09-29 01:53:08.200: ERROR/AndroidRuntime(4611): at dalvik.system.NativeStart.main(Native Method)
谢谢你!!