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AndroidStudio在AndroidManifest.xml添加权限后，没有生效的问题

本Markdown编辑器使用[StackEdit][6]修改而来，用它写博客，将会带来全新的体验哦：

• 最近用AndroidStudio练手写一个小demo，读取本地的图片显示到UI界面，自己的AndroidStudio更新到了2.2.3，SDK更新到了25。本来AndroidStudio不是很熟，就默认的的创建一个工程。按照之前用eclipse的习惯简单的写了几行读取和展示的代码。结果报了拒绝访问的错误：
• Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/MagazineUnlock/blues-13-2.3.001-bigpicture_13_1.jpg: open failed: EACCES (Permission denied)
• 

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然后我用同样的代码在eclipse上跑了一遍，结果很正常。我就郁闷了。然后上网百度了一下，竟然是踩android6.0以后权限要动态申请。具体可以百度搜一下android6.0哪些权限要动态申请，也可以参考http://blog.csdn.net/lmj623565791/article/details/50709663；
那么怎么解决的：
办法一：

方法二：
写一个PermissionUtils的工具方法；参考：http://www.jianshu.com/p/a51593817825；
package com.lizi.huangjunjie.getpic02;

import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.provider.Settings;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.util.Log;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
* Created by huangjunjie on 2016/12/13.
*/

public class PermissionUtils {
private static final String TAG = PermissionUtils.class.getSimpleName();
public static final int CODE_RECORD_AUDIO = 0;
public static final int CODE_GET_ACCOUNTS = 1;
public static final int CODE_READ_PHONE_STATE = 2;
public static final int CODE_CALL_PHONE = 3;
public static final int CODE_CAMERA = 4;
public static final int CODE_ACCESS_FINE_LOCATION = 5;
public static final int CODE_ACCESS_COARSE_LOCATION = 6;
public static final int CODE_READ_EXTERNAL_STORAGE = 7;
public static final int CODE_WRITE_EXTERNAL_STORAGE = 8;
public static final int CODE_MULTI_PERMISSION = 100;

public static final String PERMISSION_RECORD_AUDIO = Manifest.permission.RECORD_AUDIO;public static final String PERMISSION_GET_ACCOUNTS = Manifest.permission.GET_ACCOUNTS;public static final String PERMISSION_READ_PHONE_STATE = Manifest.permission.READ_PHONE_STATE;public static final String PERMISSION_CALL_PHONE = Manifest.permission.CALL_PHONE;public static final String PERMISSION_CAMERA = Manifest.permission.CAMERA;public static final String PERMISSION_ACCESS_FINE_LOCATION = Manifest.permission.ACCESS_FINE_LOCATION;public static final String PERMISSION_ACCESS_COARSE_LOCATION = Manifest.permission.ACCESS_COARSE_LOCATION;public static final String PERMISSION_READ_EXTERNAL_STORAGE = Manifest.permission.READ_EXTERNAL_STORAGE;public static final String PERMISSION_WRITE_EXTERNAL_STORAGE = Manifest.permission.WRITE_EXTERNAL_STORAGE;private static final String[] requestPermissions = {        PERMISSION_RECORD_AUDIO,        PERMISSION_GET_ACCOUNTS,        PERMISSION_READ_PHONE_STATE,        PERMISSION_CALL_PHONE,        PERMISSION_CAMERA,        PERMISSION_ACCESS_FINE_LOCATION,        PERMISSION_ACCESS_COARSE_LOCATION,        PERMISSION_READ_EXTERNAL_STORAGE,        PERMISSION_WRITE_EXTERNAL_STORAGE};interface PermissionGrant {    void onPermissionGranted(int requestCode);}/** * Requests permission. * * @param activity * @param requestCode request code, e.g. if you need request CAMERA permission,parameters is PermissionUtils.CODE_CAMERA */public static void requestPermission(final Activity activity, final int requestCode, PermissionGrant permissionGrant) {    if (activity == null) {        return;    }    Log.i(TAG, "requestPermission requestCode:" + requestCode);    if (requestCode < 0 || requestCode >= requestPermissions.length) {        Log.w(TAG, "requestPermission illegal requestCode:" + requestCode);        return;    }    final String requestPermission = requestPermissions[requestCode];    //如果是6.0以下的手机，ActivityCompat.checkSelfPermission()会始终等于PERMISSION_GRANTED，    // 但是，如果用户关闭了你申请的权限，ActivityCompat.checkSelfPermission(),会导致程序崩溃(java.lang.RuntimeException: Unknown exception code: 1 msg null)，    // 你可以使用try{}catch(){},处理异常，也可以在这个地方，低于23就什么都不做，    // 个人建议try{}catch(){}单独处理，提示用户开启权限。

// if (Build.VERSION.SDK_INT < 23) {
// return;
// }

    int checkSelfPermission;    try {        checkSelfPermission = ActivityCompat.checkSelfPermission(activity, requestPermission);    } catch (RuntimeException e) {        Toast.makeText(activity, "please open this permission", Toast.LENGTH_SHORT)                .show();        Log.e(TAG, "RuntimeException:" + e.getMessage());        return;    }    if (checkSelfPermission != PackageManager.PERMISSION_GRANTED) {        Log.i(TAG, "ActivityCompat.checkSelfPermission != PackageManager.PERMISSION_GRANTED");        if (ActivityCompat.shouldShowRequestPermissionRationale(activity, requestPermission)) {            Log.i(TAG, "requestPermission shouldShowRequestPermissionRationale");            shouldShowRationale(activity, requestCode, requestPermission);        } else {            Log.d(TAG, "requestCameraPermission else");            ActivityCompat.requestPermissions(activity, new String[]{requestPermission}, requestCode);        }    } else {        Log.d(TAG, "ActivityCompat.checkSelfPermission ==== PackageManager.PERMISSION_GRANTED");        Toast.makeText(activity, "opened:" + requestPermissions[requestCode], Toast.LENGTH_SHORT).show();        permissionGrant.onPermissionGranted(requestCode);    }}private static void requestMultiResult(Activity activity, String[] permissions, int[] grantResults, PermissionGrant permissionGrant) {    if (activity == null) {        return;    }    //TODO    Log.d(TAG, "onRequestPermissionsResult permissions length:" + permissions.length);    Map<String, Integer> perms = new HashMap<>();    ArrayList<String> notGranted = new ArrayList<>();    for (int i = 0; i < permissions.length; i++) {        Log.d(TAG, "permissions: [i]:" + i + ", permissions[i]" + permissions[i] + ",grantResults[i]:" + grantResults[i]);        perms.put(permissions[i], grantResults[i]);        if (grantResults[i] != PackageManager.PERMISSION_GRANTED) {            notGranted.add(permissions[i]);        }    }    if (notGranted.size() == 0) {        Toast.makeText(activity, "all permission success" + notGranted, Toast.LENGTH_SHORT)                .show();        permissionGrant.onPermissionGranted(CODE_MULTI_PERMISSION);    } else {        openSettingActivity(activity, "those permission need granted!");    }}/** * 一次申请多个权限 */public static void requestMultiPermissions(final Activity activity, PermissionGrant grant) {    final List<String> permissionsList = getNoGrantedPermission(activity, false);    final List<String> shouldRationalePermissionsList = getNoGrantedPermission(activity, true);    //TODO checkSelfPermission    if (permissionsList == null || shouldRationalePermissionsList == null) {        return;    }    Log.d(TAG, "requestMultiPermissions permissionsList:" + permissionsList.size() + ",shouldRationalePermissionsList:" + shouldRationalePermissionsList.size());    if (permissionsList.size() > 0) {        ActivityCompat.requestPermissions(activity, permissionsList.toArray(new String[permissionsList.size()]),                CODE_MULTI_PERMISSION);        Log.d(TAG, "showMessageOKCancel requestPermissions");    } else if (shouldRationalePermissionsList.size() > 0) {        showMessageOKCancel(activity, "should open those permission",                new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        ActivityCompat.requestPermissions(activity, shouldRationalePermissionsList.toArray(new String[shouldRationalePermissionsList.size()]),                                CODE_MULTI_PERMISSION);                        Log.d(TAG, "showMessageOKCancel requestPermissions");                    }                });    } else {        grant.onPermissionGranted(CODE_MULTI_PERMISSION);    }}private static void shouldShowRationale(final Activity activity, final int requestCode, final String requestPermission) {    //TODO    String[] permissionsHint = activity.getResources().getStringArray(R.array.permissions);    showMessageOKCancel(activity, "Rationale: " + permissionsHint[requestCode], new DialogInterface.OnClickListener() {        @Override        public void onClick(DialogInterface dialog, int which) {            ActivityCompat.requestPermissions(activity,                    new String[]{requestPermission},                    requestCode);            Log.d(TAG, "showMessageOKCancel requestPermissions:" + requestPermission);        }    });}private static void showMessageOKCancel(final Activity context, String message, DialogInterface.OnClickListener okListener) {    new AlertDialog.Builder(context)            .setMessage(message)            .setPositiveButton("OK", okListener)            .setNegativeButton("Cancel", null)            .create()            .show();}/** * @param activity * @param requestCode  Need consistent with requestPermission * @param permissions * @param grantResults */public static void requestPermissionsResult(final Activity activity, final int requestCode, @NonNull String[] permissions,                                            @NonNull int[] grantResults, PermissionGrant permissionGrant) {    if (activity == null) {        return;    }    Log.d(TAG, "requestPermissionsResult requestCode:" + requestCode);    if (requestCode == CODE_MULTI_PERMISSION) {        requestMultiResult(activity, permissions, grantResults, permissionGrant);        return;    }    if (requestCode < 0 || requestCode >= requestPermissions.length) {        Log.w(TAG, "requestPermissionsResult illegal requestCode:" + requestCode);        Toast.makeText(activity, "illegal requestCode:" + requestCode, Toast.LENGTH_SHORT).show();        return;    }    Log.i(TAG, "onRequestPermissionsResult requestCode:" + requestCode + ",permissions:" + permissions.toString()            + ",grantResults:" + grantResults.toString() + ",length:" + grantResults.length);    if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {        Log.i(TAG, "onRequestPermissionsResult PERMISSION_GRANTED");        //TODO success, do something, can use callback        permissionGrant.onPermissionGranted(requestCode);    } else {        //TODO hint user this permission function        Log.i(TAG, "onRequestPermissionsResult PERMISSION NOT GRANTED");        //TODO        String[] permissionsHint = activity.getResources().getStringArray(R.array.permissions);        openSettingActivity(activity, "Result" + permissionsHint[requestCode]);    }}private static void openSettingActivity(final Activity activity, String message) {    showMessageOKCancel(activity, message, new DialogInterface.OnClickListener() {        @Override        public void onClick(DialogInterface dialog, int which) {            Intent intent = new Intent();            intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);            Log.d(TAG, "getPackageName(): " + activity.getPackageName());            Uri uri = Uri.fromParts("package", activity.getPackageName(), null);            intent.setData(uri);            activity.startActivity(intent);        }    });}/** * @param activity * @param isShouldRationale true: return no granted and shouldShowRequestPermissionRationale permissions, false:return no granted and !shouldShowRequestPermissionRationale * @return */public static ArrayList<String> getNoGrantedPermission(Activity activity, boolean isShouldRationale) {    ArrayList<String> permissions = new ArrayList<>();    for (int i = 0; i < requestPermissions.length; i++) {        String requestPermission = requestPermissions[i];        //TODO checkSelfPermission        int checkSelfPermission = -1;        try {            checkSelfPermission = ActivityCompat.checkSelfPermission(activity, requestPermission);        } catch (RuntimeException e) {            Toast.makeText(activity, "please open those permission", Toast.LENGTH_SHORT)                    .show();            Log.e(TAG, "RuntimeException:" + e.getMessage());            return null;        }        if (checkSelfPermission != PackageManager.PERMISSION_GRANTED) {            Log.i(TAG, "getNoGrantedPermission ActivityCompat.checkSelfPermission != PackageManager.PERMISSION_GRANTED:" + requestPermission);            if (ActivityCompat.shouldShowRequestPermissionRationale(activity, requestPermission)) {                Log.d(TAG, "shouldShowRequestPermissionRationale if");                if (isShouldRationale) {                    permissions.add(requestPermission);                }            } else {                if (!isShouldRationale) {                    permissions.add(requestPermission);                }                Log.d(TAG, "shouldShowRequestPermissionRationale else");            }        }    }    return permissions;}

}
然后再你的调用activity里调用：
public void showCamera(View view) {
Log.i(TAG, “Show camera button pressed. Checking permission.”);
PermissionUtils.requestPermission(this, PermissionUtils.CODE_CAMERA, mPermissionGrant);
}

public void getAccounts(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_GET_ACCOUNTS, mPermissionGrant);}public void callPhone(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_CALL_PHONE, mPermissionGrant);}public void readPhoneState(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_READ_PHONE_STATE, mPermissionGrant);}public void accessFineLocation(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_ACCESS_FINE_LOCATION, mPermissionGrant);}public void accessCoarseLocation(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_ACCESS_COARSE_LOCATION, mPermissionGrant);}public void readExternalStorage(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_READ_EXTERNAL_STORAGE, mPermissionGrant);}public void writeExternalStorage(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_WRITE_EXTERNAL_STORAGE, mPermissionGrant);}public void recordAudio(View view) {    PermissionUtils.requestPermission(this, PermissionUtils.CODE_RECORD_AUDIO, mPermissionGrant);}private PermissionUtils.PermissionGrant mPermissionGrant = new PermissionUtils.PermissionGrant() {    @Override    public void onPermissionGranted(int requestCode) {        switch (requestCode) {            case PermissionUtils.CODE_RECORD_AUDIO:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_RECORD_AUDIO", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_GET_ACCOUNTS:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_GET_ACCOUNTS", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_READ_PHONE_STATE:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_READ_PHONE_STATE", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_CALL_PHONE:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_CALL_PHONE", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_CAMERA:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_CAMERA", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_ACCESS_FINE_LOCATION:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_ACCESS_FINE_LOCATION", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_ACCESS_COARSE_LOCATION:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_ACCESS_COARSE_LOCATION", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_READ_EXTERNAL_STORAGE:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_READ_EXTERNAL_STORAGE", Toast.LENGTH_SHORT).show();                break;            case PermissionUtils.CODE_WRITE_EXTERNAL_STORAGE:                Toast.makeText(MainActivity.this, "Result Permission Grant CODE_WRITE_EXTERNAL_STORAGE", Toast.LENGTH_SHORT).show();                break;            default:                break;        }    }};/** * Callback received when a permissions request has been completed. */@Overridepublic void onRequestPermissionsResult(final int requestCode, @NonNull String[] permissions,                                       @NonNull int[] grantResults) {    PermissionUtils.requestPermissionsResult(this, requestCode, permissions, grantResults, mPermissionGrant);}

比如我的是通过button调用的就在button的单击事件前，调用下面2个方法：
readExternalStorage(button);
writeExternalStorage(button);

然后跑一下就可以了。

参考资料：http://blog.csdn.net/lmj623565791/article/details/50709663；
http://www.jianshu.com/p/a51593817825；