问题
I am new to android studio, i was previously working on android version 5.1 for my app and it worked fine but now in 6 i am not able to get permission or i am not sure if my method is wrong. I am making an app which uses the list of access points available for my mobile. But even though i am granted permission my app does not show me the wifi list but the same code works well for earlier versions.
Mainactivity:
package com.wiferange.wifi_test;
import android.Manifest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.net.wifi.ScanResult;
import android.net.wifi.WifiManager;
import android.os.Build;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Gravity;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
import java.util.List;
public class MainActivity extends AppCompatActivity {
ListView lv;
String lists[]={"a","b"};
WifiManager wifi;
String wifis[];
WifiScanReceiver wifiReciever;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
lv = (ListView)findViewById(R.id.listView);
wifi=(WifiManager)getSystemService(Context.WIFI_SERVICE);
wifiReciever = new WifiScanReceiver();
getPermission();
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
}
});
}
protected void onPause() {
unregisterReceiver(wifiReciever);
super.onPause();
}
protected void onResume() {
registerReceiver(wifiReciever, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
super.onResume();
}
private void getPermission() {
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && checkSelfPermission(Manifest.permission.ACCESS_WIFI_STATE) != PackageManager.PERMISSION_GRANTED){
requestPermissions(new String[]{Manifest.permission.ACCESS_WIFI_STATE},0x12345);
// lv.setAdapter(new ArrayAdapter<String>(getApplicationContext(),android.R.layout.simple_list_item_1,lists));
//After this point you wait for callback in onRequestPermissionsResult(int, String[], int[]) overriden method
}else{
wifi.startScan();
//do scanning, permission was previously granted; or legacy device
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) { //funcitno executes when some permission was granted
if (requestCode == 0x12345) {
for (int grantResult : grantResults) {
if (grantResult != PackageManager.PERMISSION_GRANTED) { //check if permission was already grnated and start scannig if yes
wifi .startScan() ;
return;
}
}
getPermission(); //ask for permission if not given
}
}
private class WifiScanReceiver extends BroadcastReceiver {
public void onReceive(Context c, Intent intent) {
List<ScanResult> wifiScanList = wifi.getScanResults();
wifis = new String[wifiScanList.size()];
for(int i = 0; i < wifiScanList.size(); i++){
wifis[i] = ((wifiScanList.get(i)).toString());
}
lv.setAdapter(new ArrayAdapter<String>(getApplicationContext(),android.R.layout.simple_list_item_1,wifis));
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.wiferange.wifi_test">
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Kindly help me to solve this . Thanks in advance !!!!
回答1:
You are requesting the wrong runtime permission. As per the Android 6.0 changes:
To access the hardware identifiers of nearby external devices via Bluetooth and Wi-Fi scans, your app must now have the ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION permissions
You must request and be granted one of those runtime permissions to do wifi scans.
回答2:
It seems in order to work well with WifiManager when scanning the Connections from Android 6.0 it needs to access your location, so that is either the fine location or the coarse location, I added the following to my Manifest file:
I think this is what you need.
Application (WiFi connections) doesn't work anymore on Android 6.0 Marshmallow
回答3:
you need to look at the permissions if that is in automatically granted permission list or in Dangerous permission list. if that was in Dangerous permission list so than you need run time permission like android M. just go though this link You are requesting the wrong runtime permission. ACCESS_WIFI_STATE permission is in automatically granted permissions no need to access it runtime.
来源：https://stackoverflow.com/questions/40078747/permission-for-accessing-wifi-in-android-6