WebView使用input file控件打开相册上传图片

使用 WebView 直接用 控件选择相册图片

package com.moguzhuan.android.zhuan;

import android.annotation.TargetApi;
import android.app.Activity;
import android.content.ClipData;
import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;


public class MainActivity extends AppCompatActivity {

    private final static String TAG = "MainActivity";

    private String TMP_URL = "http://m.zhuan.com";
    private WebView webview;
    private String MIME = "image/*";

    private ValueCallback<Uri> mUploadMessage;
    private ValueCallback<Uri[]> mUploadCallbackAboveL;

    private final static int FILECHOOSER_RESULTCODE = 1;


    private void assignViews() {
        webview = (WebView) findViewById(R.id.webview);
        WebSettings settings = webview.getSettings();
        settings.setUseWideViewPort(true);
        settings.setLoadWithOverviewMode(true);
        settings.setJavaScriptEnabled(true);
        settings.setSupportZoom(true);
        webview.setVerticalScrollBarEnabled(true);
        webview.setHorizontalScrollBarEnabled(true);
        webview.setWebViewClient(new WebViewClient(){
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                // TODO Auto-generated method stub
                //返回值是true的时候控制去WebView打开，为false调用系统浏览器或第三方浏览器
                view.loadUrl(url);
                return true;
            }
        });
        webview.setWebChromeClient(new WebChromeClient(){
            // For Android 3.0+
            public void openFileChooser(ValueCallback<Uri> uploadMsg) {
                Log.d(TAG, "openFileChoose(ValueCallback<Uri> uploadMsg)");
                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType(MIME);
                MainActivity.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE);
            }

            // For Android 3.0+
            public void openFileChooser( ValueCallback uploadMsg, String acceptType ) {
                Log.d(TAG, "openFileChoose( ValueCallback uploadMsg, String acceptType )");
                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType(MIME);
                MainActivity.this.startActivityForResult(
                        Intent.createChooser(i, "File Browser"),
                        FILECHOOSER_RESULTCODE);
            }
            //For Android 4.1
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture){
                Log.d(TAG, "openFileChoose(ValueCallback<Uri> uploadMsg, String acceptType, String capture)");
                mUploadMessage = uploadMsg;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType(MIME);
                MainActivity.this.startActivityForResult( Intent.createChooser( i, "File Browser" ), MainActivity.FILECHOOSER_RESULTCODE );
            }
            // For Android 5.0+
            public boolean onShowFileChooser (WebView webView, ValueCallback<Uri[]> filePathCallback, WebChromeClient.FileChooserParams fileChooserParams) {
                Log.d(TAG, "onShowFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture)");
                mUploadCallbackAboveL = filePathCallback;
                Intent i = new Intent(Intent.ACTION_GET_CONTENT);
                i.addCategory(Intent.CATEGORY_OPENABLE);
                i.setType(MIME);
                MainActivity.this.startActivityForResult(
                        Intent.createChooser(i, "File Browser"),
                        FILECHOOSER_RESULTCODE);
                return true;
            }
        });
        webview.loadUrl(TMP_URL);

    }

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

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

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    private void onActivityResultAboveL(int requestCode, int resultCode, Intent data) {
        if (requestCode != FILECHOOSER_RESULTCODE
                || mUploadCallbackAboveL == null) {
            return;
        }

        Uri[] results = null;
        if (resultCode == Activity.RESULT_OK) {
            if (data == null) {

            } else {
                String dataString = data.getDataString();
                ClipData clipData = data.getClipData();

                if (clipData != null) {
                    results = new Uri[clipData.getItemCount()];
                    for (int i = 0; i < clipData.getItemCount(); i++) {
                        ClipData.Item item = clipData.getItemAt(i);
                        results[i] = item.getUri();
                    }
                }

                if (dataString != null)
                    results = new Uri[]{Uri.parse(dataString)};
            }
        }
        mUploadCallbackAboveL.onReceiveValue(results);
        mUploadCallbackAboveL = null;
        return;
    }
}

assignViews 方法中需增加一段代码，让app使用默认的浏览器直接打开链接，否则会弹出选择第三方浏览器的窗口：

webview.setWebViewClient(new WebViewClient(){
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        // TODO Auto-generated method stub
        //返回值是true的时候控制去WebView打开，为false调用系统浏览器或第三方浏览器
        view.loadUrl(url);
        return true;
    }
});

参考：
https://gitcafe.com/saymagic/Webviewdemo/blob/master/app/src/main/java/cn/saymagic/webviewdemo/MainActivity.java

在 AndroidManifest.xml 中添加网络访问权限：

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

另外，需要注意一点就是通过这种方式上传的图片，在服务端接收到的 MIME 类型为

application/octet-stream

而不是一般的 image/jpeg 这种哦