首页 > 解决方案 > Android webView 我可以打开图库并选择/上传文件,但需要像浏览器一样选择相机或图库

问题描述

在我试图使input type='file' accept='image/ '* 按钮在 webView 中像在浏览器中一样工作的详尽搜索中,我遇到了一些实际上对我有用的代码,但是(如您所见在下面的代码中)它会打开图库以直接选择文件而无需任何提示。我需要更改什么以提示用户使用相机或从图库中选择一个文件。我认为我复制的代码已经有很多需要的部分来允许相机功能,但我不认为向用户展示选项是我复制的代码的目标 - 所以他们可能已经删除了必要的部分。

我的 AndroidManifest.xml 有(我认为是)所需的条目:

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-feature android:name="android.hardware.camera" android:required="true" />
    <uses-feature android:name="android.hardware.camera.front" android:required="true" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />

MainActivity.java

package {name redacted for SO};

import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.net.Uri;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.CookieManager;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebResourceError;
import android.webkit.WebResourceRequest;
import android.webkit.WebView;
import android.webkit.WebViewClient;


public class MainActivity extends AppCompatActivity {

    public WebView webView;
//    private float m_downX;
//    private SwipeRefreshLayout mySwipeRefreshLayout;

    private static final int STORAGE_PERMISSION_CODE = 123;
    private final static int FILECHOOSER_RESULTCODE=1;
    private ValueCallback<Uri[]> mUploadMessage;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        webView = findViewById(R.id.webView);


        webView.loadUrl("https://{url redacted for SO}");
        initWebView();
    }

    //Requesting permission
    private void requestStoragePermission() {
        if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED){
            openFileExplorer();
            return;
        }


        if (ActivityCompat.shouldShowRequestPermissionRationale(this, android.Manifest.permission.READ_EXTERNAL_STORAGE)) {
            //If the user has denied the permission previously your code will come to this block
            //Here you can explain why you need this permission
            //Explain here why you need this permission
        }
        //And finally ask for the permission
        ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE}, STORAGE_PERMISSION_CODE);
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {

        //Checking the request code of our request
        if (requestCode == STORAGE_PERMISSION_CODE) {

            //If permission is granted
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                openFileExplorer();
                //Displaying a toast
//                Toast.makeText(this, "Permission granted now you can read the storage", Toast.LENGTH_LONG).show();
            } else {
                //Displaying another toast if permission is not granted
//                Toast.makeText(this, "Oops you just denied the permission", Toast.LENGTH_LONG).show();
            }
        }

    }
    private void openFileExplorer(){
        Intent i = new Intent(Intent.ACTION_GET_CONTENT);
        i.addCategory(Intent.CATEGORY_OPENABLE);
        i.setType("image/*");
        MainActivity.this.startActivityForResult( Intent.createChooser( i, "File Chooser" ), MainActivity.FILECHOOSER_RESULTCODE );

    }

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

    public void requestCameraPermission() {
        if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, new String[] { android.Manifest.permission.CAMERA, android.Manifest.permission.WRITE_EXTERNAL_STORAGE }, 0);
        }
    }


    @Override
    public void onBackPressed() {
        if (webView.canGoBack()) {
            webView.goBack();
            return;
        }
        super.onBackPressed();
    }
    private void initWebView() {
        webView.setWebChromeClient(new MyWebChromeClient(this));
        webView.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                super.onPageStarted(view, url, favicon);

                invalidateOptionsMenu();
            }

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

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

            @Override
            public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
                super.onReceivedError(view, request, error);
                invalidateOptionsMenu();
            }


        });
        webView.clearCache(true);
        webView.clearHistory();
//        webView.getSettings().setJavaScriptEnabled(true);
//        webView.setWebViewClient(new WebViewClient());
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setDomStorageEnabled(true);
        webView.setOverScrollMode(WebView.OVER_SCROLL_NEVER);
        webView.setHorizontalScrollBarEnabled(false);
        CookieManager cookieManager = CookieManager.getInstance();
        cookieManager.setAcceptThirdPartyCookies(webView,true);
    }

    private class MyWebChromeClient extends WebChromeClient {
        Context context;

        public MyWebChromeClient(Context context) {
            super();
            this.context = context;
        }

        @Override
        public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback,
                                         WebChromeClient.FileChooserParams fileChooserParams) {
            mUploadMessage = filePathCallback;
            requestStoragePermission();
            requestCameraPermission();

            return true;
        }
    }
}

标签: androidwebview

解决方案


我向该主题发布了一个不同的更新问题,并找到了我正在寻找的内容。我不知道我是否应该将答案从那里复制到这里的这篇文章,或者只是发布一个链接,所以我只会发布一个链接。我希望它可以帮助别人。

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