您好我正在为我的网站制作一个webview应用程序。那个网站有一个文件选择器，上传棒棒糖，上传工作，没问题，在清单中我已经给了读外部存储权限，但我知道新的marshmallow需要请求权限显示。因此，如何在此活动中实现（请求用户允许读取外部存储以进行文件上载），假设这是我上传页面webview的主要活动。 Main2Activity是处理上传页面webview的活动页面
Main2Activity.java代码：
package com.mywebsite.mywebsite;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.content.res.Configuration;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.NonNull;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Toast;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class Main2Activity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener{
WebView webView;
private static final String TAG = Main2Activity.class.getSimpleName();
private String mCM;
private ValueCallback<Uri> mUM;
private ValueCallback<Uri[]> mUMA;
private final static int FCR=1;
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent){
super.onActivityResult(requestCode, resultCode, intent);
if(Build.VERSION.SDK_INT >= 21){
Uri[] results = null;
//Check if response is positive
if(resultCode== Activity.RESULT_OK){
if(requestCode == FCR){
if(null == mUMA){
return;
}
if(intent == null){
//Capture Photo if no image available
if(mCM != null){
results = new Uri[]{Uri.parse(mCM)};
}
}else{
String dataString = intent.getDataString();
if(dataString != null){
results = new Uri[]{Uri.parse(dataString)};
}
}
}
}
mUMA.onReceiveValue(results);
mUMA = null;
}else{
if(requestCode == FCR){
if(null == mUM) return;
Uri result = intent == null || resultCode != RESULT_OK ? null : intent.getData();
mUM.onReceiveValue(result);
mUM = null;
}
}
}
@SuppressLint({"SetJavaScriptEnabled", "WrongViewCast"})
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
//new code start
Toolbar toolbar2 = (Toolbar) findViewById(R.id.toolbar2);
setSupportActionBar(toolbar2);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout2);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar2, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view2);
navigationView.setNavigationItemSelectedListener(this);
//new code end
webView = (WebView) findViewById(R.id.main2);
assert webView != null;
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled(true);
webSettings.setAllowFileAccess(true);
if(Build.VERSION.SDK_INT >= 21){
webSettings.setMixedContentMode(0);
webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
}else if(Build.VERSION.SDK_INT >= 19){
webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
}else if(Build.VERSION.SDK_INT >=11 && Build.VERSION.SDK_INT < 19){
webView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
webView.setWebViewClient(new Callback());
webView.setWebViewClient(new CustomWebViewClient());
webView.loadUrl("http://path to upload page");
webView.setWebChromeClient(new WebChromeClient(){
//For Android 3.0+
public void openFileChooser(ValueCallback<Uri> uploadMsg){
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
Main2Activity.this.startActivityForResult(Intent.createChooser(i,"File Chooser"), FCR);
}
// For Android 3.0+, above method not supported in some android 3+ versions, in such case we use this
public void openFileChooser(ValueCallback uploadMsg, String acceptType){
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
Main2Activity.this.startActivityForResult(
Intent.createChooser(i, "File Browser"),
FCR);
}
//For Android 4.1+
public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture){
mUM = uploadMsg;
Intent i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
Main2Activity.this.startActivityForResult(Intent.createChooser(i, "File Chooser"), Main2Activity.FCR);
}
//For Android 5.0+
public boolean onShowFileChooser(
WebView webView, ValueCallback<Uri[]> filePathCallback,
WebChromeClient.FileChooserParams fileChooserParams){
if(mUMA != null){
mUMA.onReceiveValue(null);
}
mUMA = filePathCallback;
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if(takePictureIntent.resolveActivity(Main2Activity.this.getPackageManager()) != null){
File photoFile = null;
try{
photoFile = createImageFile();
takePictureIntent.putExtra("PhotoPath", mCM);
}catch(IOException ex){
Log.e(TAG, "Image file creation failed", ex);
}
if(photoFile != null){
mCM = "file:" + photoFile.getAbsolutePath();
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));
}else{
takePictureIntent = null;
}
}
Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
contentSelectionIntent.setType("image/*");
Intent[] intentArray;
if(takePictureIntent != null){
intentArray = new Intent[]{takePictureIntent};
}else{
intentArray = new Intent[0];
}
Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentArray);
startActivityForResult(chooserIntent, FCR);
return true;
}
});
}
//new code start
@Override
public boolean onCreateOptionsMenu(Menu menu2) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main2, menu2);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings2) {
Intent i = new Intent(Main2Activity.this, MainActivity.class);
startActivity(i);
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_local) {
// Handle the camera action
webView.loadUrl("http://example.com/index.php?/category/1&mobile=true");
} else if (id == R.id.nav_spices2) {
webView.loadUrl("http://example.com/index.php?/category/84&mobile=true");
} else if (id == R.id.nav_vherbarium2) {
webView.loadUrl("http://example.com/index.php?/category/36&mobile=true");
} else if (id == R.id.nav_usersupload2) {
webView.loadUrl("http://example.com/index.php?/category/user&mobile=true");
} else if (id == R.id.nav_recent2) {
webView.loadUrl("http://example.com/index.php?/recent_pics&mobile=true");
} else if (id == R.id.nav_login2) {
webView.loadUrl("http://example.com/identification.php?mobile=true");
} else if (id == R.id.nav_register2) {
webView.loadUrl("http://example.com/register.php?mobile=true");
} else if (id == R.id.nav_search2) {
webView.loadUrl("http://example.com/search.php?mobile=true");
} else if (id == R.id.nav_contact2) {
webView.loadUrl("http://example.com/index.php?/contact/&mobile=true");
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout2);
drawer.closeDrawer(GravityCompat.START);
return true;
}
public class CustomWebViewClient extends WebViewClient {
@Override
public boolean shouldOverrideUrlLoading(WebView webView, String url) {
if(url.contains("something")) return true;
return false; //Default is to not override unless our condition is met.
}
public void onPageFinished(WebView webView, String url) {
String webUrl = webView.getUrl();
System.out.println(webUrl);
if(url.startsWith("http://example/oAuth/auth.php?provider=Facebook&openid_identifier=&init_auth=1#_=_")){
String redirectUrl = "http:/// link to upload page.php";
webView.loadUrl(redirectUrl);
return;
}
super.onPageFinished(webView, url);
}
}
//new code end
public class Callback extends WebViewClient {
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl){
Toast.makeText(getApplicationContext(), "Failed loading app! Check internet connection", Toast.LENGTH_SHORT).show();
}
}
// Create an image file
private File createImageFile() throws IOException{
@SuppressLint("SimpleDateFormat") String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "img_"+timeStamp+"_";
File storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
return File.createTempFile(imageFileName,".jpg",storageDir);
}
@Override
public boolean onKeyDown(int keyCode, @NonNull KeyEvent event){
if(event.getAction() == KeyEvent.ACTION_DOWN){
switch(keyCode){
case KeyEvent.KEYCODE_BACK:
if(webView.canGoBack()){
webView.goBack();
}else{
finish();
}
return true;
}
}
return super.onKeyDown(keyCode, event);
}
@Override
public void onConfigurationChanged(Configuration newConfig){
super.onConfigurationChanged(newConfig);
}
}
答案 0 :(得分：1)
检查权限（source）：
public boolean isStoragePermissionGranted() {
if (Build.VERSION.SDK_INT >= 23) {
if (checkSelfPermission(android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
== PackageManager.PERMISSION_GRANTED) {
Log.v(TAG,"Permission is granted");
return true;
} else {
Log.v(TAG,"Permission is revoked");
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
return false;
}
}
else { //permission is automatically granted on sdk<23 upon installation
Log.v(TAG,"Permission is granted");
return true;
}
}
还实现权限回调：
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if(grantResults[0]== PackageManager.PERMISSION_GRANTED){
Log.v(TAG,"Permission: "+permissions[0]+ "was "+grantResults[0]);
//resume tasks needing this permission
}
}
为了更轻松地处理所有Android版本的权限，请查看Hotchemi的这个名为PermissionsDispatcher的第三方库。