我正在嘗試存盤從 JSON 字串獲取的資料，以便可以離線使用該應用程式，但我不斷收到此錯誤：
引起：com.google.firebase.database.DatabaseException：無效的 Firebase 資料庫路徑：https ://my-application-fe439-default-rtdb.europe-west1.firebasedatabase.app/ 。Firebase 資料庫路徑不得包含“.”、“#”、“$”、“[”或“]”
我的問題是，我寫錯了代碼嗎？因為路徑看起來不錯。我試圖洗掉“ - ”，但我得到了同樣的錯誤。這是我撰寫代碼的類：
public class NutritionPlan1 extends AppCompatActivity {
private String TAG = MainActivity.class.getSimpleName();
private ListView lv;
ArrayList<HashMap<String, String>> resultList;
@Override
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);
switch (item.getItemId()) {
case android.R.id.home:
finish();
break;
}
return true;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nutrition_plan1);
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("https://my-application-fe439-default-rtdb.europe-west1.firebasedatabase.app/");
myRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
// This method is called once with the initial value and again
// whenever data at this location is updated.
String value = dataSnapshot.getValue(String.class);
Log.d(TAG, "Value is: " value);
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
// Failed to read value
Log.w(TAG, "Failed to read value.", error.toException());
}
});
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
if (getSupportActionBar() != null){
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);
}
resultList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
new GetContacts().execute();
}
private class GetContacts extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
Toast.makeText(NutritionPlan1.this,"Json Data is downloading",Toast.LENGTH_LONG).show();
}
@Override
protected Void doInBackground(Void... arg0) {
HttpHandler sh = new HttpHandler();
// Making a request to url and getting response
String url = "https://api.spoonacular.com/recipes/complexSearch?diet=vegetarian&addRecipeNutrition=true&apiKey=d22842b0ca9148839497a0022902ae97";
String jsonStr = sh.makeServiceCall(url);
Log.e(TAG, "Response from url: " jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
JSONArray results = jsonObj.getJSONArray("results");
// looping through All items
for (int i = 0; i < results.length(); i ) {
JSONObject c = results.getJSONObject(i);
String title = c.getString("title");
String healthScore = c.getString("healthScore");
String servings = c.getString("servings");
String pricePerServing = c.getString("pricePerServing");
String readyInMinutes = c.getString("readyInMinutes");
// tmp hash map for single contact
HashMap<String, String> result = new HashMap<>();
// adding each child node to HashMap key => value
result.put("title",title);
result.put("pricePerServing","Cost: " pricePerServing);
result.put("servings","Servings: " servings);
result.put("healthScore","Health Score: " healthScore);
result.put("readyInMinutes","Time to cook: " readyInMinutes "minutes" );
// adding contact to contact list
resultList.add(result);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " e.getMessage());
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " e.getMessage(),Toast.LENGTH_LONG).show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG).show();
}
});
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
ListAdapter adapter = new SimpleAdapter(NutritionPlan1.this, resultList,
R.layout.list_nutrition_plans, new String[]{ "title","pricePerServing","servings","healthScore","readyInMinutes"},
new int[]{R.id.title, R.id.pricePerServing,R.id.servings,R.id.healthscore,R.id.readyInMinutes});
lv.setAdapter(adapter);
}
}
}
uj5u.com熱心網友回復：
而不是這個：
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("https://my-application-fe439-default-rtdb.europe-west1.firebasedatabase.app/");
應該使用這個：
FirebaseDatabase database = FirebaseDatabase.getInstance("https://my-application-fe439-default-rtdb.europe-west1.firebasedatabase.app/");
DatabaseReference myRef = database.getReference();
另請參閱有關連接到實時資料庫的檔案，其中說：
要獲取對默認資料庫以外的資料庫的參考
us-central1，您必須將資料庫 URL 傳遞給getInstance().
轉載請註明出處，本文鏈接：https://www.uj5u.com/qita/484118.html
標籤：爪哇 安卓 火力基地 firebase-实时数据库