Question

所以我有一个Android WebView，旨在导航m.facebook.com，我无法使图像上传工作。当我点击上传图片按钮（在我的WebView上的Facebook上）时没有任何反应。

我在m.facebook.com网站上按下的按钮就是这个：

Facebook Upload Image

我已按如下方式定义了我的WebChromeClient：

_webview.setWebChromeClient(new WebChromeClient() {  
    public void openFileChooser( ValueCallback<Uri> uploadMsg, String acceptType ) {  
        // BREAKPOINT HERE
        mUploadMessage = uploadMsg;  
        Intent i = new Intent(Intent.ACTION_GET_CONTENT);  
        i.addCategory(Intent.CATEGORY_OPENABLE);  
        i.setType("image/*");  
        MainActivity.this.startActivityForResult( Intent.createChooser( i, "" ), MainActivity.FILECHOOSER_RESULTCODE ); 
    }

    // For Android < 3.0
    public void openFileChooser( ValueCallback<Uri> uploadMsg ) {
      openFileChooser( uploadMsg, "" );
    }  

    // For Android > 4.1
    public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture){
      openFileChooser( uploadMsg, "" );
    }
});

我从Chirag的回答中得到了以前的堆栈溢出帖子：Android WebView File Upload

我在这里设置了一个断点，在这里点了一小段时间＆＃34;注释是，即使按下m.facebook.com上的上传照片按钮，它也永远不会被击中。我有READ_EXTERNAL_STORAGE权限集。我的最小api版本是9，我的目标是21.

我还设置了一个WebViewClient，我定义如下：

private class MyWebViewClient extends WebViewClient {
    Activity activity;

    public MyWebViewClient(Activity myActivity){
        activity = myActivity;

    }
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url){
        // This function is never called when I click the upload photo
        // button.

        // ... Do Stuff
    }

    public void onLoadResource(WebView view, String url){

        // The following if statement's predicate returns false if the 
        // upload image button is pressed, so it's contents are of no consequence
        if(url.startsWith(LINK_STRING)){
            // ...
        }

    }
}

为了完整性，我已经包含了我的一部分清单：

<uses-sdk
    android:minSdkVersion="9"
    android:targetSdkVersion="21" />

<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >

    <meta-data android:name="com.google.android.gms.version"
       android:value="@integer/google_play_services_version"/>

    <activity android:name="com.google.android.gms.ads.AdActivity"
        android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"
        android:alwaysRetainTaskState="true"/> <!-- Remove this if this doesn't correct the crashing issue -->

    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:screenOrientation="portrait" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

我的问题是：如何允许WebView组件从图库和相机上传图像？

非常感谢您提供的任何帮助！

Answer 1

您必须扩展WebChromeClient并添加四种方法，如您所关联的问题中所述。

您可以使用此库为您执行以下操作：

https://github.com/delight-im/Android-AdvancedWebView

...或者查看源代码以了解它是如何完成的：

https://github.com/delight-im/Android-AdvancedWebView/blob/ecff154ef390a0dbdb5337bd5dea2055205c104f/Source/src/im/delight/android/webview/AdvancedWebView.java#L524

Answer 2

添加以下onActivityResult来处理on filechooser。这些功能允许您请求文件选择器和对文件选择器执行的操作。 view demo

@Override 
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) { 
    if(requestCode==FILECHOOSER_RESULTCODE){ 
       if (null == mUploadMessage) 
           return;
            Uri result = intent == null || resultCode != RESULT_OK ? null :intent.getData();
             mUploadMessage.onReceiveValue(result); mUploadMessage = null;
      } 
    }

您的MyWebViewClient应如下所示

private class MyWebViewClient extends WebViewClient {
        Activity activity;

        public MyWebViewClient(Activity myActivity){
            activity = myActivity;

        }
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url){
            // This function is never called when I click the upload photo
            // button.

            // ... Do Stuff
        }

        public void onLoadResource(WebView view, String url){

            // The following if statement's predicate returns false if the 
            // upload image button is pressed, so it's contents are of no consequence
            if(url.startsWith(LINK_STRING)){
                // ...
            }

        }
    @Override 
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) { 
    if(requestCode==FILECHOOSER_RESULTCODE){ 
       if (null == mUploadMessage) 
           return;
            Uri result = intent == null || resultCode != RESULT_OK ? null :intent.getData();
             mUploadMessage.onReceiveValue(result); mUploadMessage = null;
      } 
    }
    }

您可以从 here 下载演示同样的工作演示

Android WebView允许在m.facebook.com上上传图片

2 个答案: