Android webview 允许使用当前的 Android Studio 访问相机

Question

我一直在尝试让一个简单的输入按钮在我的 webview 上工作，以访问相机和文件。我读过的解决方案从几行代码到我在 Android Studio 中下载并打开的盲目 github 项目链接(Os-Fileup 和其他)没有解释，它们通常有几十个文件，没有任何内容确实对我有帮助，因为我不知道自己在寻找什么。

我尝试了各种解决方案，包括这个或那个包、请求权限等，但没有一个能解决我的问题，因为我可能实现不正确，或者它们适用于更旧版本的 Android 或 Android Studio。我使用的是最新版本的 Android Studio，并且只针对 Oreo 8.1(minSdkVersion 27 和 targetSdkVersion 28)。

对于我的 webview 应用程序的初始设置，我按照我在某处找到的一个简单教程进行操作，一切正常 - 除了相机。

我终于在某个地方读到，而不是授予应用程序权限(例如:访问相机、设备上的应用程序)不会传递到 WebView - 所以这就是我卡住的地方。只有两个文件 - AndroidManifest 和 MainActivity.java ... 所以这两个文件看起来像你在下面看到的 - 我到底要在这些文件中更改什么才能使按钮在应用程序中正常工作浏览器中的同一设备？

来自 webview.loadURL 页面的按钮:

<input id='uploadImage' type='file' accept='image/*' name='image' />

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="redacted.name.here">

    <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" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_ns_n"
        android:label="@string/app_name"
        android:roundIcon="@drawable/ic_ns_n"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:configChanges="orientation|screenSize">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

主 Activity .java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.CookieManager;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
    private WebView webview;

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        onCreate(savedInstanceState);
    }
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        webview =(WebView)findViewById(R.id.webView);
        webview.setWebViewClient(new WebViewClient());
        webview.getSettings().setJavaScriptEnabled(true);
        webview.getSettings().setDomStorageEnabled(true);
        webview.setOverScrollMode(WebView.OVER_SCROLL_NEVER);
        webview.loadUrl("https://redacted.url.here");
        CookieManager cookieManager = CookieManager.getInstance();
        cookieManager.setAcceptThirdPartyCookies(webview,true);
    }
}

Answer 1

在进一步搜索之后，我发现了一些更新的代码，我可以编辑这些代码以使其适合我，其中我会看到一个对话框，询问我是要使用相机还是选择一个文件。

编辑包名称和 URL 以匹配您的项目。我在下面的代码中留下了我从中复制的代码中注释掉的所有部分，但我将在我自己的项目中删除其中的大部分。

我希望这对其他人有帮助。

我没有更改我的 HTML 或 AndroidManifest.xml 文件。

主 Activity .java

package {put your package name here};

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.os.Environment;
import android.os.Parcelable;
import android.provider.MediaStore;
import android.support.annotation.RequiresApi;
import android.webkit.CookieManager;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebResourceRequest;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

import java.io.File;

public class MainActivity extends Activity {

    private WebView webview;
    private ValueCallback<Uri> mUploadMessage;
    private ValueCallback<Uri[]> mUploadMessages;
    private Uri mCapturedImageURI = null;
    private static final int MY_CAMERA_REQUEST_CODE = 100;
    private static final int FILECHOOSER_RESULTCODE = 1;

    @RequiresApi(api = Build.VERSION_CODES.M)
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        webview =(WebView)findViewById(R.id.webView);



        webview.setOverScrollMode(WebView.OVER_SCROLL_NEVER);
        webview.loadUrl("https://{put your URL here");
        CookieManager cookieManager = CookieManager.getInstance();
        cookieManager.setAcceptThirdPartyCookies(webview,true);


        webview.setWebViewClient(new WebViewClient());

        WebSettings webSettings = webview.getSettings();
        webSettings.setJavaScriptEnabled(true);
        webSettings.setDomStorageEnabled(true);
        webview.getSettings().setJavaScriptEnabled(true);
        webview.getSettings().setDomStorageEnabled(true);
        webview.getSettings().setPluginState(WebSettings.PluginState.ON);
        webview.getSettings().setAppCacheEnabled(false);
        webview.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);
        webview.getSettings().setUseWideViewPort(true);
        webview.getSettings().setLoadWithOverviewMode(true);
        webview.getSettings().setBuiltInZoomControls(false);
        webview.getSettings().setSupportZoom(false);
        webview.getSettings().setDefaultZoom(WebSettings.ZoomDensity.FAR);
        webview.getSettings().setDomStorageEnabled(true);
        webview.getSettings().setDatabaseEnabled(true);
        webview.getSettings().setDatabasePath("/data/data/" + webview.getContext().getPackageName() + "/databases/");

        webview.setWebChromeClient(new WebChromeClient() {

            // For api level bellow 24
            public boolean shouldOverrideUrlLoading(WebView view, String url) {

                if (url.startsWith("http")) {
                    // Return false means, web view will handle the link
                    return false;
                }

                return false;
            }


            // From api level 24
            @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
            public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
                /*Toast.makeText(mcontext, "New Method",Toast.LENGTH_SHORT).show();*/

                // Get the tel: url
                String url = request.getUrl().toString();

                if (url.startsWith("http")) {
                    // Return false means, web view will handle the link
                    return false;
                }

                return false;
            }

            // openFileChooser for Android 3.0+

           /* public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
                mUploadMessage = uploadMsg;
                openImageChooser();
            }*/

            // For Lollipop 5.0+ Devices

            public boolean onShowFileChooser(WebView mWebView, ValueCallback<Uri[]> filePathCallback, WebChromeClient.FileChooserParams fileChooserParams) {
                mUploadMessages = filePathCallback;
                openImageChooser();
                return true;
            }

            // openFileChooser for Android < 3.0

           /* public void openFileChooser(ValueCallback<Uri> uploadMsg) {
                openFileChooser(uploadMsg, "");
            }

            //openFileChooser for other Android versions

            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
                openFileChooser(uploadMsg, acceptType);
            }*/
        });

    }

    private void openImageChooser() {
        try {

            File imageStorageDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "FolderName");

            if (!imageStorageDir.exists()) {
                imageStorageDir.mkdirs();
            }
            File file = new File(imageStorageDir + File.separator + "IMG_" + String.valueOf(System.currentTimeMillis()) + ".jpg");
            mCapturedImageURI = Uri.fromFile(file);

            final Intent captureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            captureIntent.putExtra(MediaStore.EXTRA_OUTPUT, mCapturedImageURI);

            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.addCategory(Intent.CATEGORY_OPENABLE);
            i.setType("image/*");

            Intent chooserIntent = Intent.createChooser(i, "Image Chooser");
            chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, new Parcelable[]{captureIntent});

            startActivityForResult(chooserIntent, FILECHOOSER_RESULTCODE);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
        super.onActivityResult(requestCode, resultCode, intent);

        if (requestCode == FILECHOOSER_RESULTCODE) {

            if (null == this.mUploadMessage && null == this.mUploadMessages) {
                return;
            }

           /* Uri result;
            if (requestCode != RESULT_OK){
                result = null;
            }else {
                result = intent == null ? this.mCapturedImageURI : intent.getData();
            }
            this.mUploadMessage.onReceiveValue(result);
            this.mUploadMessage = null;*/
            if (null != mUploadMessage) {
                handleUploadMessage(requestCode, resultCode, intent);

            } else if (mUploadMessages != null) {
                handleUploadMessages(requestCode, resultCode, intent);
            }
        }
    }

    private void handleUploadMessage(int requestCode, int resultCode, Intent intent) {
        Uri result = null;
        try {
            if (resultCode != RESULT_OK) {
                result = null;
            } else {
                // retrieve from the private variable if the intent is null

                result = intent == null ? mCapturedImageURI : intent.getData();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        mUploadMessage.onReceiveValue(result);
        mUploadMessage = null;
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    private void handleUploadMessages(int requestCode, int resultCode, Intent intent) {
        Uri[] results = null;
        try {
            if (resultCode != RESULT_OK) {
                results = null;
            } else {
                if (intent != null) {
                    String dataString = intent.getDataString();
                    ClipData clipData = intent.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)};
                    }
                } else {
                    results = new Uri[]{mCapturedImageURI};
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        mUploadMessages.onReceiveValue(results);
        mUploadMessages = null;
    }

}