android6,0申請權限

android6.0開啓權限遇到的一些坑

一個小白，記錄學習遇到的一些坑

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最近在作android方面的實驗，作到用LocationManager進行定位，發現單獨在AndroidManifest.xml文件中

聲明開啓權限，不可以真正的開啓想要的權限，說是安全問題，其實在平常中咱們都很清楚的一個權限開啓方式。

遇到問題，第一個想到的就是上網搜索，可是能解決問題的答案少的可憐，因此就記錄下來，防止下次在遇到，不知所措。

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廢話很少說，其實很簡單。在你報錯的地方加上一個判斷語句，判斷當前的sdk版本是否大於23，大於就申請開啓權限；不然直接跳過去執行你的代碼

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(this,new String[]{
                Manifest.permission.ACCESS_FINE_LOCATION,
                Manifest.permission.ACCESS_COARSE_LOCATION
        },2);
        return;
    }
}

下面是我要執行的代碼，這段代碼就是要申請開啓權限的核心

locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0,
        locationListener);

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原函數是

public static void requestPermissions(final @NonNull Activity activity,
        final @NonNull String[] permissions, final @IntRange(from = 0) int requestCode) {

參數：

1. activity: 顧名思義，就是要申請權限的那個activity。

2. permissions： 要申請的權限名稱，好比我申請的有

   Manifest.permission.ACCESS_FINE_LOCATION,衛星定位要用到
    Manifest.permission.ACCESS_COARSE_LOCATION.基站定位要用到

3. requestCode： 隨便填個數，目前我瞭解這個參數在重寫onRequestPermissionsResult這個方法用的到，重寫這個方法能夠了解到權限有沒有開啓成功。

   能夠經過重寫該函數去顯示權限開啓成功仍是失敗

   @Override
   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                                          int[] grantResults) {
       if (requestCode == 2) {
           for (int i = 0; i < permissions.length; i++) {
               if (grantResults[i] == PERMISSION_GRANTED) {
                   Toast.makeText(this, "" + "權限" + permissions[i] + "申請成功", Toast.LENGTH_SHORT).show();
               } else {
                   Toast.makeText(this, "" + "權限" + permissions[i] + "申請失敗", Toast.LENGTH_SHORT).show();
               }
           }
       }
   }

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下面我貼出我本次作的一個實驗

• 佈局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/t1"/>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/t2"/>
</LinearLayout>

• java代碼

package com.example.locationmanage;

import android.Manifest;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.location.LocationProvider;
import android.os.Build;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;

import java.text.SimpleDateFormat;
import java.util.Date;

import static android.content.pm.PackageManager.PERMISSION_GRANTED;

public class MainActivity extends AppCompatActivity {
    TextView info;
    TextView location;
    LocationManager locationManager;
    LocationListener locationListener;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        info = findViewById(R.id.t1);
        location = findViewById(R.id.t2);
        //locationManger初始化
        locationListener_init();
        locationManager_init();
    }


    void locationManager_init() {
        locationManager = (LocationManager) this.getSystemService(LOCATION_SERVICE);
        locationListener_init();


        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PERMISSION_GRANTED) {
                // TODO: Consider calling
                //    Activity#requestPermissions
                // here to request the missing permissions, and then overriding
                //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                //                                          int[] grantResults)
                // to handle the case where the user grants the permission. See the documentation
                // for Activity#requestPermissions for more details.
                ActivityCompat.requestPermissions(this,new String[]{
                        Manifest.permission.ACCESS_FINE_LOCATION,
                        Manifest.permission.ACCESS_COARSE_LOCATION
                },2);
                return;
            }
        }
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0,
                locationListener);

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions,
                                           int[] grantResults) {
        if (requestCode == 2) {
            for (int i = 0; i < permissions.length; i++) {
                if (grantResults[i] == PERMISSION_GRANTED) {
                    Toast.makeText(this, "" + "權限" + permissions[i] + "申請成功", Toast.LENGTH_SHORT).show();
                } else {
                    Toast.makeText(this, "" + "權限" + permissions[i] + "申請失敗", Toast.LENGTH_SHORT).show();
                }
            }
        }
    }


    void locationListener_init() {
        locationListener = new LocationListener() {
            @Override
            public void onLocationChanged(Location location) {
                SimpleDateFormat dateFormat = (SimpleDateFormat)
                        SimpleDateFormat.getTimeInstance(2);
                String str = dateFormat.format(new Date(location.getTime()));
                info.setText("時間：" + str + "\n");
                info.append("經度：" + location.getLongitude() + "\n");
                info.append("緯度：" + location.getLatitude() + "\n");
                info.append("海拔：" + location.getAltitude() + "\n");
            }

            @Override
            public void onStatusChanged(String provider, int status, Bundle extras) {
                if (status == LocationProvider.AVAILABLE)
                    info.setText("當前的gps可見的\n");
                else if (status == LocationProvider.OUT_OF_SERVICE)
                    info.setText("當前的gps服務區外\n");
                else if (status == LocationProvider.TEMPORARILY_UNAVAILABLE)
                    info.setText("當前的gps被暫停\n");
            }

            @Override
            public void onProviderEnabled(String provider) {
                info.setText("當前的gps被啓動\n");
            }

            //被警用時觸發
            @Override
            public void onProviderDisabled(String provider) {
                info.setText("當前的gps被禁用\n");
            }
        };

    }
}

• 應用清單文件AndroidManifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.locationmanage">

    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

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