有没有办法跟踪此异常:焦点搜索返回了无法获得焦点的视图

Question

我使用以下堆栈获得Crashlytics的崩溃日志:

Fatal Exception: java.lang.IllegalStateException: focus search returned a view that wasn't able to take focus!
   at android.widget.TextView.onKeyUp(TextView.java:6413)
   at android.view.KeyEvent.dispatch(KeyEvent.java:2712)
   at android.view.View.dispatchKeyEvent(View.java:9960)
   at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1630)
   at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1630)
   at android.widget.ScrollView.dispatchKeyEvent(ScrollView.java:387)
   at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1630)
   at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1630)
   at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:1630)
   at com.android.internal.policy.DecorView.superDispatchKeyEvent(DecorView.java:406)
   at com.android.internal.policy.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1798)
   at android.app.Activity.dispatchKeyEvent(Activity.java:3024)
   at com.android.internal.policy.DecorView.dispatchKeyEvent(DecorView.java:320)
   at android.view.ViewRootImpl$ViewPostImeInputStage.processKeyEvent(ViewRootImpl.java:4331)
   at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:4302)
   at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
   at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
   at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
   at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3999)
   at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
   at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4056)
   at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
   at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3906)
   at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3872)
   at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3880)
   at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3853)
   at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:6247)
   at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:6221)
   at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:6182)
   at android.view.ViewRootImpl$ViewRootHandler.handleMessage(ViewRootImpl.java:3651)
   at android.os.Handler.dispatchMessage(Handler.java:102)
   at android.os.Looper.loop(Looper.java:154)
   at android.app.ActivityThread.main(ActivityThread.java:6121)
   at java.lang.reflect.Method.invoke(Method.java)
   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889)
   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)

我能找到的最接近的答案是:致命的崩溃:焦点搜索返回了一个无法获得焦点的视图

但我的问题是,如何跟踪此次崩溃的来源？很难指出它,因为崩溃日志对于实际崩溃的确切来源不够充分

Answer 1

我通过显式为 EditText 的 focusSearch 方法返回一个值来解决这个崩溃问题。（否则，Android 将自行计算出它认为的下一个可聚焦视图）。子类化 EditText 并提供以下附加代码：

private MyEditText nextFocusField;

@Override
public View focusSearch(@ViewCompat.FocusRealDirection int direction) {
    if (direction == FOCUS_DOWN) {
        return (View) nextFocusField;
    }   
    return super.focusSearch(direction);
}   

public void setNextFocusField(MyEditText nextFocusField) {
    this.nextFocusField = nextFocusField;
}

然后在设置 EditText 的片段类中，我确保为每个字段提供下一个 EditText。按照我想要的顺序将它们收集到 ArrayList 中后，我像这样分配它们：

int editTextCount = editTexts.size();
for (int i = 0;  i < editTextCount;  i++) {
    MyEditText editText = (MyEditText) editTexts.get(i);
    if (i < editTextCount - 1) { // if not the last item
        editText.setNextFocusField((MyEditText) editTexts.get(i + 1)); 
    }    
    else if (editTextCount > 1) { 
        editText.setNextFocusField(null);
    }    
}