2018-02-04 Webview无法打开本地图片选择器解决方

一位大神朋友写的一个网页里面有个选择图片的功能，但是在我的Webview里面却打不开本地图片选择器。（浏览器中可以）。特意搜索了一下，查到了解决办法，亲测有效。

安卓系统3x 4x 5x上的行为都不同，处理也不同。总的来说就是重写Webview里面FileChooser的方法。

设置自定义WebChromeClient。

new WebChromeClient() {
    //扩展支持alert事件
    @Override
    public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
        AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext());
        builder.setTitle("xxx提示").setMessage(message).setPositiveButton("确定", null);
        builder.setCancelable(false);
        builder.setIcon(R.drawable.ic_launcher);
        AlertDialog dialog = builder.create();
        dialog.show();
        result.confirm();
        return true;
    }
    //扩展浏览器上传文件
    //3.0++版本
    public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
        openFileChooserImpl(uploadMsg);
    }
    //3.0--版本
    public void openFileChooser(ValueCallback<Uri> uploadMsg) {
        openFileChooserImpl(uploadMsg);
    }
    public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
        openFileChooserImpl(uploadMsg);
    }
    // For Android > 5.0
    public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> uploadMsg, WebChromeClient.FileChooserParams fileChooserParams) {
        openFileChooserImplForAndroid5(uploadMsg);
        return true;
    }
}

将其设置给webview。

webView.setWebChromeClient(...)

打开图片选择器方法

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

    private void openFileChooserImplForAndroid5(ValueCallback<Uri[]> uploadMsg) {
        mUploadMessageForAndroid5 = uploadMsg;
        Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
        contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
        contentSelectionIntent.setType("image/*");

        Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
        chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
        chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");

        startActivityForResult(chooserIntent, FILECHOOSER_RESULTCODE_FOR_ANDROID_5);
    }

重写onActivityResult方法

    @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;

        } else if (requestCode == FILECHOOSER_RESULTCODE_FOR_ANDROID_5) {
            if (null == mUploadMessageForAndroid5)
                return;
            Uri result = (intent == null || resultCode != RESULT_OK) ? null : intent.getData();
            if (result != null) {
                mUploadMessageForAndroid5.onReceiveValue(new Uri[]{result});
            } else {
                mUploadMessageForAndroid5.onReceiveValue(new Uri[]{});
            }
            mUploadMessageForAndroid5 = null;
        }
    }

至此，已经解决该问题。