PermissionsDispatcher是一个基于注解、帮助开发者简单处理Android 6.0系统中的运行时权限的开源库。避免了开发者编写大量繁琐的样板代码。

开源地址：https://github.com/hotchemi/PermissionsDispatcher

文档介绍：http://hotchemi.github.io/PermissionsDispatcher/

下面详细介绍一下如何在Android Studio上使用该开源库。

1、添加依赖

首先在项目工程下的build.gradle文件中加入对maven仓库依赖引入的支持。

allprojects {
    repositories {
        jcenter()
        mavenCentral()
    }
}

之后在module下的build.gradle文件中添加两项依赖：

compile 'com.github.hotchemi:permissionsdispatcher:2.3.1'
annotationProcessor 'com.github.hotchemi:permissionsdispatcher-processor:2.3.1'

并将targetSdkVersion设为23，即：targetSdkVersion 23

2、在Activity或Fragment中使用

注解列表：

注意：被注解的方法不能是私有方法。

只有@RuntimePermissions和@NeedsPermission是必须的，其余注解均为可选。当使用了@RuntimePermissions和@NeedsPermission之后，需要点击菜单栏中Build菜单下的Make Project，或者按快捷键Ctrl + F9编译整个项目，编译器会在app\build\intermediates\classes\debug目录下与被注解的Activity同一个包下生成一个辅助类，名称为被注解的Activity名称+PermissionsDispatcher.class，如图所示：

生成的辅助类

接下来可以调用辅助类里面的方法完成应用的权限请求了。

在需要调用权限的位置调用辅助类里面的xxxWithCheck方法，xxx是被@NeedsPermission注解的方法名。如：

MainActivityPermissionsDispatcher.showCameraWithCheck(this);

之后，还需要重写该Activity的onRequestPermissionsResult()方法，其方法内调用辅助类的onRequestPermissionsResult()方法，如下：

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    // NOTE: delegate the permission handling to generated method
    MainActivityPermissionsDispatcher.onRequestPermissionsResult(this, requestCode, grantResults);
}

完整的MainActivity如下所示。

• MainActivity.java

@RuntimePermissions
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.button_camera).setOnClickListener(this);
        findViewById(R.id.button_contacts).setOnClickListener(this);
    }

    @Override
    public void onClick(@NonNull View v) {
        switch (v.getId()) {
            case R.id.button_camera:
                // NOTE: delegate the permission handling to generated method
                MainActivityPermissionsDispatcher.showCameraWithCheck(this);
                break;
            case R.id.button_contacts:
                // NOTE: delegate the permission handling to generated method
                MainActivityPermissionsDispatcher.showContactsWithCheck(this);
                break;
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        // NOTE: delegate the permission handling to generated method
        MainActivityPermissionsDispatcher.onRequestPermissionsResult(this, requestCode, grantResults);
    }

    @NeedsPermission(Manifest.permission.CAMERA)
    void showCamera() {
        // NOTE: Perform action that requires the permission. If this is run by PermissionsDispatcher, the permission will have been granted
        getSupportFragmentManager().beginTransaction()
                .replace(R.id.sample_content_fragment, CameraPreviewFragment.newInstance())
                .addToBackStack("camera")
                .commitAllowingStateLoss();
    }

    @NeedsPermission({Manifest.permission.READ_CONTACTS, Manifest.permission.WRITE_CONTACTS})
    void showContacts() {
        // NOTE: Perform action that requires the permission.
        // If this is run by PermissionsDispatcher, the permission will have been granted
        getSupportFragmentManager().beginTransaction()
                .replace(R.id.sample_content_fragment, ContactsFragment.newInstance())
                .addToBackStack("contacts")
                .commitAllowingStateLoss();
    }

    @OnShowRationale(Manifest.permission.CAMERA)
    void showRationaleForCamera(PermissionRequest request) {
        // NOTE: Show a rationale to explain why the permission is needed, e.g. with a dialog.
        // Call proceed() or cancel() on the provided PermissionRequest to continue or abort
        showRationaleDialog(R.string.permission_camera_rationale, request);
    }

    @OnShowRationale({Manifest.permission.READ_CONTACTS, Manifest.permission.WRITE_CONTACTS})
    void showRationaleForContact(PermissionRequest request) {
        // NOTE: Show a rationale to explain why the permission is needed, e.g. with a dialog.
        // Call proceed() or cancel() on the provided PermissionRequest to continue or abort
        showRationaleDialog(R.string.permission_contacts_rationale, request);
    }

    @OnPermissionDenied(Manifest.permission.CAMERA)
    void onCameraDenied() {
        // NOTE: Deal with a denied permission, e.g. by showing specific UI
        // or disabling certain functionality
        Toast.makeText(this, R.string.permission_camera_denied, Toast.LENGTH_SHORT).show();
    }

    @OnNeverAskAgain(Manifest.permission.CAMERA)
    void onCameraNeverAskAgain() {
        Toast.makeText(this, R.string.permission_camera_never_askagain, Toast.LENGTH_SHORT).show();
    }

    public void onBackClick(View view) {
        getSupportFragmentManager().popBackStack();
    }

    private void showRationaleDialog(@StringRes int messageResId, final PermissionRequest request) {
        new AlertDialog.Builder(this)
                .setPositiveButton("允许", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(@NonNull DialogInterface dialog, int which) {
                        request.proceed();
                    }
                })
                .setNegativeButton("拒绝", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(@NonNull DialogInterface dialog, int which) {
                        request.cancel();
                    }
                })
                .setCancelable(false)
                .setMessage(messageResId)
                .show();
    }
}

3、附：危险权限和权限组列表

Android官方文档：https://developer.android.com/guide/topics/security/permissions.html#normal-dangerous

摘录如下：

4、附：Demo下载

http://download.csdn.net/detail/u012939909/9722890