我有这个代码
//get Info from Json
ic_Spe_categorie = findViewById(R.id.ic_Spe_categorief);
StringRequest request = new StringRequest(Request.Method.GET, URL, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
final HashMap<String,Integer> mapList=new HashMap<>();
try {
JSONObject source = new JSONObject(response);
JSONArray path = source.getJSONArray("hotel");
Spe_categorie = new String[path.length()];
for (int i = 0; i < path.length(); i++){
JSONObject object = path.getJSONObject(i);
if(object.getString("hotel_id").equals("100972")){
String categorie = object.getString("categorie_chambre_name");
Spe_categorie[i] = categorie ;
Log.d("categorie", object.getString("categorie_chambre_name"));
ArrayAdapter arrayAdapter_cat = new ArrayAdapter(SearchHotelActivity.this, android.R.layout.simple_spinner_item , Spe_categorie);
arrayAdapter_cat.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
ic_Spe_categorie.setAdapter(arrayAdapter_cat);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
}) ;
queue.add(request);
我试图使用json REST API 用数据库中的行(category_chamber_name(填充微调器(ic_Spe_categore(
如果我不使用if-if语句，微调器实际上会填充所有行(category_chabre_name(
我只需要链接到我的酒店id(100972(的线路(category_chabre_name(
当我试图设置一个条件，如果hotel_id等于数据库中已经存在我的酒店id(100972(
给我这个错误
E/AndroidRuntime: FATAL EXCEPTION: main
Process: ma.transatour.transatourmaroc, PID: 12734
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:453)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:415)
at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:204)
at android.widget.Spinner.onMeasure(Spinner.java:602)
at android.support.v7.widget.AppCompatSpinner.onMeasure(AppCompatSpinner.java:426)
at android.view.View.measure(View.java:23169)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:715)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:461)
at android.view.View.measure(View.java:23169)
at android.widget.ScrollView.measureChildWithMargins(ScrollView.java:1308)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.widget.ScrollView.onMeasure(ScrollView.java:350)
at android.view.View.measure(View.java:23169)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:715)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:461)
at android.view.View.measure(View.java:23169)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:715)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:461)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.support.v7.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:400)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1535)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:825)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:704)
at android.view.View.measure(View.java:23169)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6749)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:716)
at android.view.View.measure(View.java:23169)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2718)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1572)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1855)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1460)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7183)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:949)
at android.view.Choreographer.doCallbacks(Choreographer.java:761)
at android.view.Choreographer.doFrame(Choreographer.java:696)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:935)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
您可能需要检查您的JSON对象是否具有"hotel_id"键。只需放置一个调试点或在使用前与has进行检查即可。