[置顶] 解决WebView不支持input type=file

1.定义activity

 private ValueCallback<Uri> mUploadMessage;
 public ValueCallback<Uri[]> uploadMessage;
 public static final int REQUEST_SELECT_FILE = 100;
 private final static int FILECHOOSER_RESULTCODE = 2;

2.重写shouldOverrideUrlLoading

  webView.setWebViewClient(new WebViewClient() {
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                //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 false;
            }
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
            }
            @Override
            public void onPageFinished(WebView view, String url) {
            }
        });

3. 使用返回键的方式防止网页重定向

        webView.setOnKeyListener(new View.OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (event.getAction() == KeyEvent.ACTION_DOWN) {
                    if (keyCode == KeyEvent.KEYCODE_BACK && webView.canGoBack()) {
                        webView.goBack();
                        return true;
                    }
                }
                return false;
            }
        });

4.重写WebChromeClient

    webView.setWebChromeClient(new WebChromeClient() {
        // For 3.0+ Devices (Start)
        // onActivityResult attached before constructor
        protected void openFileChooser(ValueCallback uploadMsg, String acceptType)
        {
            mUploadMessage = uploadMsg;
            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.addCategory(Intent.CATEGORY_OPENABLE);
            i.setType("*/*");
            startActivityForResult(Intent.createChooser(i, "File Browser"), FILECHOOSER_RESULTCODE);
        }
        // For Lollipop 5.0+ Devices
        @TargetApi(Build.VERSION_CODES.LOLLIPOP)
        public boolean onShowFileChooser(WebView mWebView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams)
        {
            if (uploadMessage != null) {
                uploadMessage.onReceiveValue(null);
                uploadMessage = null;
            }
            uploadMessage = filePathCallback;
            Intent intent = fileChooserParams.createIntent();
            try
            {
                startActivityForResult(intent, REQUEST_SELECT_FILE);
            } catch (ActivityNotFoundException e)
            {
                uploadMessage = null;
                Toast.makeText(getBaseContext(), "Cannot Open File Chooser", Toast.LENGTH_LONG).show();
                return false;
            }
            return true;
        }
        //For Android 4.1 only
        protected void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture)
        {
            mUploadMessage = uploadMsg;
            Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
            intent.addCategory(Intent.CATEGORY_OPENABLE);
            intent.setType("*/*");
            startActivityForResult(Intent.createChooser(intent, "File Browser"), FILECHOOSER_RESULTCODE);
        }

        protected void openFileChooser(ValueCallback<Uri> uploadMsg)
        {
            mUploadMessage = uploadMsg;
            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.addCategory(Intent.CATEGORY_OPENABLE);
            i.setType("*/*");
            startActivityForResult(Intent.createChooser(i, "File Chooser"), FILECHOOSER_RESULTCODE);
        }     
    });

5.回调

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch (requestCode) {         
            case REQUEST_SELECT_FILE:
                if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
                {

                if (uploadMessage == null)
                    return;
                uploadMessage.onReceiveValue(WebChromeClient.FileChooserParams.parseResult(resultCode, data));
                uploadMessage = null;
             }
            break;
        case FILECHOOSER_RESULTCODE:
            if (null == mUploadMessage)
                return;
            // Use MainActivity.RESULT_OK if you're implementing WebView inside Fragment
            // Use RESULT_OK only if you're implementing WebView inside an Activity
            Uri result = data == null || resultCode != MainActivity.RESULT_OK ? null : data.getData();
            mUploadMessage.onReceiveValue(result);
            mUploadMessage = null;
            break;
    }

}