我正在通过 https://reactnavigation.org/docs/en/upgrading-from-4.x.html和https://reactnavigation.org/docs/en/compatibility.html将 React Navigation 库从 4.xx 升级到 5 。
我收到错误：
NavigationDebug Error: Error: The 'navigation' object hasn't been initialized yet. This might happen if you don't have a navigator mounted, or if the navigator hasn't finished mounting. You can ensure that all navigators have mounted after the callback to 'useEffect' is called in your root component. See https://reactnavigation.org/docs/en/navigating-without-navigation-prop.html#handling-initialization for more details.
at dispatch (BaseNavigationContainer.tsx:202)
at Object.acc.<computed> [as navigate] (BaseNavigationContainer.tsx:245)
at Object.navigate (NavigationService.ts:20)
at SplashScreen.redirectUser (splash-screen.tsx:234)
at SplashScreen.proxiedMethod …很抱歉打扰你们，但我一直在努力让这个工作正常进行。
我想要它做什么：
EditText 显示提示。
用户单击 EditText，打开微调器并选择他们的性别。然后将其转换为字符串并放入 EditText(gender) 中
它实际上在做什么： 在用户单击它之前，“男性”微调器中的第一个元素已经放入我的 EditText 中。（我从未看到我的提示：“性别”）......并且微调器不会当我尝试单击 EditText（性别）时完全打开
这是怎么回事？
我的代码：
private Spinner sexSpinner;
String[] arrayForSpinner = {"Male", "Female"};
//Inside OnCreate method:
sexSpinner = (Spinner)findViewById(R.id.spinner);
adapter = new ArrayAdapter<String>(this, R.layout.spinner_row, arrayForSpinner);
sexSpinner.setAdapter(adapter);
sexSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view,int position, long id) {
gender.setText(sexSpinner.getSelectedItem().toString());
}
gender.setOnFocusChangeListener(new View.OnFocusChangeListener() {
@Override
public void onFocusChange(View arg0, boolean hasFocus) {
// TODO Auto-generated method stub
if(hasFocus){
sexSpinner.performClick();
}
}
});
布局：
<EditText
android:layout_width="75dp"
android:layout_height="wrap_content"
android:layout_marginBottom="12dp"
android:focusable="false"
android:longClickable="false" …我在我的应用程序中有一个editText,我想在用户使用(空格)时运行一些代码.所以,请给我一些关于如何做到这一点的想法.
我在Link中使用Volley Library填充ListView
"http://192.168.***.***/allquestions/prev_ans.php/?number="+phone_number+"&&query="+query"
假设,用于查询"问题改变"的Json数组是
[{"Name":"AAAAA","Id":"101010101","ques":"question change","Type":"class1","relatedFields":"Eduation","Name":"hshsusu","ans":"new answer 1","replyDate":"2015-09-14","replyTime":"21:05:39"}]
查询"newquestionforcrop"的JSON数组是
[{"Name":"AAAAA","Id":"101010101","ques":"question change","Type":"class1","relatedFields":"Eduation","Name":"hshsusu","ans":"new answer 1","replyDate":"2015-09-14","replyTime":"21:05:39"}]
问题是,当我的查询之间没有空格时,它只填充列表.
我该如何解决这个问题？