Android webview输入类型文件答案

【问题标题】：Android webview input type fileAndroid webview输入类型文件
【发布时间】：2015-03-24 00:59:02
【问题描述】：

我正在尝试从 webview 使用 android 构建 web 项目。我有一个文件<input type="file" > 类型的输入字段，让用户将文件上传到服务器，但它似乎不适用于android webview，当我点击浏览按钮时，没有任何反应。

Comp.java

package com.gururaju.bbmp;

import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.webkit.WebChromeClient;

public class Comp extends Activity {
    WebView comp;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_comp);

        WebView myWebView = (WebView) findViewById(R.id.comp);
        myWebView.setWebChromeClient(new WebChromeClient());
        myWebView.loadUrl("file:///android_asset/comp.html");

    }
}

activity_comp.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <WebView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:id="@+id/comp"
        >

        </WebView>
</LinearLayout>

comp.html（在资产文件夹中）

<!DOCTYPE html>
<html lang="en">
<head>
    <link rel="stylesheet" type="text/css" href="comp.css">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
    <h2 align="center">Post your Complaints here</h2>
    <form enctype="multipart/form-data" action="" name="complaints" method="POST">
        <input class="title" type="text" name="title" placeholder="Enter the Complaint Title" /><br />

        <div class="spacer-welcome"></div>
        <textarea name="desc" class="desc" placeholder="Your complaint description here..."></textarea><br />
        <div class="spacer-welcome1"></div>

            <input id="center" type="file" name="image" ><br />
        <input class="upload" type="submit" name="submit" value="Submit" >
    </form>
</body>
</html>

任何帮助将不胜感激。

【问题讨论】：

标签： java android html http webview

【解决方案1】：

单独的 Webview 类不支持在 facebook 上上传文件。您需要同时使用 web chrome 客户端和 webview 客户端来处理您的 android 应用程序上的文件上传，如下所示。 View more details and a working demo

package com.whatsonline.androidphotouploadonfacebook;

import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.Intent;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.view.ViewGroup;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.LinearLayout;

/**
 * Created by sada on 6/17/2016.
 */
public class upload extends Activity {

    WebView web;
    private ValueCallback<Uri> mUploadMessage;
    private final static int FILECHOOSER_RESULTCODE=1;
    LinearLayout ln1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.upload);

        web = new WebView(this);
        web.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.FILL_PARENT));

        ln1=(LinearLayout) findViewById(R.id.ln1);

        WebSettings settings=web.getSettings();
        settings.setJavaScriptEnabled(true);


        web.loadUrl("http://www.facebook.com");
        web.setWebViewClient(new myWebClient());

        web.setWebChromeClient(new WebChromeClient() {
            //The undocumented magic method override
            //Eclipse will swear at you if you try to put @Override here
            // For Android 3.0+
            public void openFileChooser(ValueCallback<Uri> uploadMsg) {

                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType("image/*");
                upload.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE);

            }

            // For Android 3.0+
            public void openFileChooser(ValueCallback uploadMsg, String acceptType) {
                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType("*/*");
                upload.this.startActivityForResult(
                        Intent.createChooser(i, "File Browser"),
                        FILECHOOSER_RESULTCODE);
            }

            //For Android 4.1
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType("image/*");
                upload.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), upload.FILECHOOSER_RESULTCODE);

            }

          });
        ln1.addView(web);
    }
    public class myWebClient extends WebViewClient
    {
        @Override

        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);

        }

        @Override

        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            view.loadUrl(url);
            return true;
        }

        @Override
        public void onPageFinished(WebView view, String url) {
            super.onPageFinished(view, url);
        }
    }

    //flipscreen not loading again
    @Override
    public void onConfigurationChanged(Configuration newConfig){
        super.onConfigurationChanged(newConfig);
    }

    @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;

        }
   }
    }

【讨论】：

【解决方案2】：

Riad 的回答指向了正确的方向，但单个回调还不足以实现。

总共有四种隐藏的 API 方法需要您实现。它们的使用取决于 Android 版本。这些方法是：

public void openFileChooser(ValueCallback<Uri> uploadMsg)
public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType)
public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture)
public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, WebChromeClient.FileChooserParams fileChooserParams)

您可以使用以下库来为您完成所有这些事情：

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

或者，您可以查看源代码以了解它是如何完成的：

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

【讨论】：

【解决方案3】：

尝试像这样实现file Chooser 方法，如末尾提供的文章链接中所述：

webView.setWebChromeClient(new WebChromeClient() {

   // openFileChooser for Android 3.0+

    public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType){ 

     // Update message
     mUploadMessage = uploadMsg;

     try{  
         // do work....

     }catch(Exception e){

          Toast.makeText(getBaseContext(), "Exception:"+e,
          Toast.LENGTH_LONG).show();
     }
}

View Details Here

【讨论】：