問題描述
Android - 將本地圖像設置為 WebView 中的 img 元素 (Android - Set a Local Image to an img element in WebView)
I am passing a local file through Javascript to set an img source and I cannot get it working. The javascript to set the path is
<img src='" + the_payload.image + "' width='" + (cellWidth()-20) + "' />
The String that I am sending is the complete file path:
file:///mnt/sdcard/Android/data/com.newvisioninteractive.android.myapp/files/c87eba4a-5349-4a55-baec-cc573a5f7571-thumb.png
I saw a post about ContentProviders and ParcelFileDescriptors but could not get that to work either.
This is for a Calendar View that displays images on certain days. It works fine when I pass in a static image, just not a local one.
Also, I have set
mWebView.getSettings().setAllowFileAccess(true);
mWebView.getSettings().setJavaScriptEnabled(true);
Do I need to set any other Permissions?
參考解法
方法 1:
The solution is in extending the ContentProvider class and Overriding the openFile(Uri, String) method
package com.packagename.provider;
public class MyProvider extends ContentProvider {
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode){
URI fileURI = URI.create( "file://" + uri.getPath() );
File file = new File( fileURI );
ParcelFileDescriptor parcel = null;
try {
parcel = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
} catch (FileNotFoundException e) {
Log.e( TAG, "Error finding: " + fileURI + "\n" + e.toString() );
}
return parcel;
}
}
Then in your AndroidManifest.xml file include
<provider
android:name=".provider.MyProvider"
android:authorities="com.packagename" />
You can then access your files which would normally be
file://sdcard/Android/data/com.packagename/image.jpg
by using
content://com.packagename/sdcard/Android/data/com.packagename/image.jpg
So essentially replace file:// with content://com.packagename
方法 2:
try using file:///android_assets/image.png and place images in the android assets
(by SPillai、SPillai、SquiresSquire)