6.0动态之后获取权限

title: 6.0动态之后获取权限
date: 2016-12-08 10:33:27
tags: Utils

在各类流氓肆虐的安卓生态环境中，6.0之前是只要一安装app就能获取到所有需要的权限了。

6.0之后，谷歌将权限分成了两种，一种普通权限，跟以前一样， AndroidManifest.xml 中声明了就可以用了

另一种是危险权限，在你的项目compileSdkVersion和targetSdkVersion均>=23的时候，这一类权限不仅需要在清单中声明，而且要在使用的时候向用户申请才行。如果还像6.0之前那样只是声明一下的话，分分钟崩给你看T.T~

java.lang.SecurityException
getDeviceId: Neither user 10204 nor current process has android.permission.READ_PHONE_STATE...
1 java.lang.RuntimeException:Unable to start activity ComponentInfo{com.aidebar.d8alarmclock/com.aidebar.d8alarmclock.activity.MainActivity}: java.lang.SecurityException: getDeviceId: Neither user 10204 nor current process has android.permission.READ_PHONE_STATE.
2 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3254)
3 ......
我自己测试的时候，MIUI不会崩。。清单中配置了就直接获取了权限，导致我没有第一时间发现这个bug···
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Bundle;
import android.provider.Settings;
import android.support.annotation.NonNull;
import android.support.design.widget.Snackbar;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    private Activity mActivity;
    public static final int REQUEST_CODE_PERMISSION = 1;
    public static final int REQUEST_CODE_PERMISSION_SETTING = 2;
    private Button btn;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mActivity = this;
        btn = (Button) findViewById(R.id.btn);
        btn.setOnClickListener(this);
     * 请求单个权限
    private void requestPermission(String permission) {
        //先判断这个权限有没有被授权
        int hasPermission = ActivityCompat.checkSelfPermission(this, permission);
        if (hasPermission == PackageManager.PERMISSION_GRANTED) {
            ToastUtils.show(this,"This permission is granted");
        }else {
            //如果没有被授权，那么就要请求用户授权
            //shouldShowRequestPermissionRationale()在第一次授权弹框之前或用户点击永不提醒之后 会返回false，其他情况都返回true
            boolean shouldShowUI = ActivityCompat.shouldShowRequestPermissionRationale(this, permission);
            SharedPreferences sp = getSharedPreferences("LOCAL_DATAS", MODE_PRIVATE);
            boolean is_first_get_permission = sp.getBoolean("is_first_request_permission", true);
            if (!shouldShowUI && !is_first_get_permission) {
                showSnackBar();
            }else {
                //系统会自动弹框请求权限
                ActivityCompat.requestPermissions(this, new String[]{permission}, REQUEST_CODE_PERMISSION);
                sp.edit().putBoolean("is_first_request_permission",false).apply();
     * 请求权限的回调
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case REQUEST_CODE_PERMISSION:
                //因为只请求单个权限，所以直接获取grantResults的第一个结果就行了
                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    ToastUtils.show(this,"you've granted the permission");
                }else{
                    ToastUtils.show(this,"you've denied the permission");
                break;
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
     * 如果用户点击了永不提醒，那么对app的使用来说是很糟糕的，我们可以通过SnackBar提示他去设置里手动打开权限
    private void showSnackBar() {
        Snackbar.make(btn,"need permission！",Snackbar.LENGTH_LONG)
                .setAction("go to setting", new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        Uri uri = Uri.fromParts("package", mActivity.getPackageName(), null);
                        Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS,uri);
                        mActivity.startActivityForResult(intent, REQUEST_CODE_PERMISSION_SETTING);
                .show();
     * 点击按钮获取权限
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn:
                requestPermission(Manifest.permission.READ_PHONE_STATE);
                break;
注释写的很详细啦，不多赘述，放在这以后要用回来拿~
有人问SnackBar为什么不是出现在屏幕底部的，请移步