小编GaR*_*eTa的帖子

这是关于在请求权限时Android Marshmallow中引入的新运行时权限模型Manifest.permission.WRITE_EXTERNAL_STORAGE.

简而言之,我所遇到的是,如果我请求(和用户允许)Manifest.permission.WRITE_EXTERNAL_STORAGE权限,应用程序将无法从外部存储目录读取和写入,直到我销毁并重新启动应用程序.

这就是我正在做/经历的事情:

我的应用程序从以下状态开始:

ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED

这是,我没有权限访问外部存储.

然后,我就像Google解释的那样请求Manifest.permission.WRITE_EXTERNAL_STORAGE的许可

private void requestWriteExternalStoragePermission() {
    // Should we show an explanation?
    if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
        new AlertDialog.Builder(this)
                .setTitle("Inform and request")
                .setMessage("You need to enable permissions, bla bla bla")
                .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        ActivityCompat.requestPermissions(MendeleyActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, RC_PERMISSION_WRITE_EXTERNAL_STORAGE);
                    }
                })
                .show();
    } else {
        ActivityCompat.requestPermissions(MendeleyActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, RC_PERMISSION_WRITE_EXTERNAL_STORAGE);
    }
}

一旦用户允许该权限,onRequestPermissionsResult就会被调用.

@Override …

由于POODLE漏洞,我在Amazon AWS中托管的服务器不再支持SSLv3.

因此,我的Android应用程序对服务器执行的第一个HTTPS连接会在建立连接时导致错误.

Error reading server response: javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x77d8ab68: Failure in SSL library, usually a protocol error
error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x7339ad74:0x00000000)
       [....]
Caused by: javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x77d8ab68: Failure in SSL library, usually a protocol error
error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x7339ad74:0x00000000)
       at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:448)
       at com.android.okhttp.Connection.upgradeToTls(Connection.java:146)
       at com.android.okhttp.Connection.connect(Connection.java:107)
       at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:294)
       at com.android.okhttp.internal.http.HttpEngine.sendSocketRequest(HttpEngine.java:255)
       at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:206)

该错误仅在第一个请求中发生.后续请求工作了一段时间.

为了解决这个问题,我试图从Android客户端接受的协议列表中删除SSL,并确保我只使用TLS.为此,我设置了一个自定义SSLSocketFactory,它从启用的协议和支持的密码套件列表中删除SSL.

/**
 * SSLSocketFactory that wraps one existing SSLSocketFactory and delegetes into it …

我正在使用Robolectric 2来测试我的Activity.这扩展了ActionBarActivity:

// This Activity uses one ActionBarCompat theme    
public class MainActivity extends ActionBarActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
        }

我的测试是:

@RunWith(RobolectricTestRunner.class)
public class MainActivityTest {

    @Test
    public void shouldBlaBlaBla() throws Exception {
        Robolectric.buildActivity(MainActivity.class).create().get();
        assert(...);
    }
}

问题是,当我告诉Robolectric创建Activity时,会抛出异常.

java.lang.NullPointerException
    at java.util.regex.Matcher.getTextLength(Matcher.java:1234)
    at java.util.regex.Matcher.reset(Matcher.java:308)
    at java.util.regex.Matcher.<init>(Matcher.java:228)
    at java.util.regex.Pattern.matcher(Pattern.java:1088)
    at org.robolectric.res.ResName.<init>(ResName.java:25)
    at org.robolectric.res.builder.RobolectricPackageManager.getActivityInfo(RobolectricPackageManager.java:70)
    at android.support.v7.app.ActionBarActivityDelegate.getUiOptionsFromMetadata(ActionBarActivityDelegate.java:157)
    at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:53)
    at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:98)
    at com.busuu.android.MainActivity.onCreate(MainActivity.java:31)
    at android.app.Activity.performCreate(Activity.java:5008)
    at org.fest.reflect.method.Invoker.invoke(Invoker.java:112)
    at org.robolectric.util.ActivityController$1.run(ActivityController.java:117)
    at org.robolectric.shadows.ShadowLooper.runPaused(ShadowLooper.java:256)
    at org.robolectric.util.ActivityController.create(ActivityController.java:111)
    at org.robolectric.util.ActivityController.create(ActivityController.java:124)
    at com.busuu.android.MainActivityTest.mainActivityShouldProvideASlidingMenu(MainActivityTest.java:16)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
    at …

我正在使用 Android Jetpack 导航组件。我有一个带有 id 的嵌套导航图，比如说嵌套图R.id.nested_graph 的第一个Fragment接收一个参数。

<navigation
        android:id="@+id/nested_graph"
        android:label="Nested Graph"
        app:startDestination="@id/firstFragment">
        <fragment
            android:id="@+id/firstFragment"
            android:name="...."
            android:label="....">
            <argument
                android:name="item_id"
                app:argType="integer" />
        </fragment>
        [...]
    </navigation>

如何使用安全 args将参数传递给嵌套图？

目前，我需要在包中手动传递参数，使用直接接收嵌套图的 id 的 API：

        val args = Bundle()
        args.putInt("item_id", itemId)
        navController.navigate(R.id.nested_graph, args)

我想使用安全参数，并执行以下操作：

        val directions = OrigininFragmentDirections.nestedGraph(itemId)
        navController.navigate(directions)

但是在尝试时，我在构建时收到以下错误：

Too many arguments for public final fun nestedGraph(): NavDirections defined 

问题是导航图预处理正在生成工厂方法来创建没有签名中所需参数的NavDirections对象。