file.exists() returns false for existing file in android

问题

In my app user can select image from sdcard and set as profile picture. Everything is working fine but when user selects image from whatsapp folder from sdcard image can not decoded.

I am using following code to decode file and display in ImageView.

if (imgFile.exists()) {                                 

Bitmap myBitmap = BitmapFactory.decodeFile(imgFile  
        .getAbsolutePath());                        

imgProfilePic.setImageBitmap(myBitmap);             
myBitmap = null;                                    
System.gc();                                        
Runtime.getRuntime().gc();                          

}

I am getting selected image path /storage/sdcard0/WhatsApp/Media/WhatsApp Images/IMG-20130804-WA0000.jpg and it exists in sdcard but file.exists always returns false. It works fine if user selects image from other folders rather than whatsapp.

Update

I am following steps like

1. click on profilepic(imageview).
2. select options(from camera,galerry,or edit)
3. open selected or captured image in CropImage Activity.
4. display cropped image.

Anyhelp would be greatly appreciated..Thanks.

回答1:

I was modifying image of other apps. I think this might be the problem. So what I did ?

select image and get path in onActivityResult()
copy image from this path in temp file using below code
use temp file for cropping and other processing

private void copyFile(File sourceFile, File destFile) throws IOException {
    if (!sourceFile.exists()) {
        return;
    }

    FileChannel source = null;
    FileChannel destination = null;
    source = new FileInputStream(sourceFile).getChannel();
    destination = new FileOutputStream(destFile).getChannel();
    if (destination != null && source != null) {
        destination.transferFrom(source, 0, source.size());
    }
    if (source != null) {
        source.close();
    }
    if (destination != null) {
        destination.close();
    }

}

Hope this may help someone else.

回答2:

If your ImageFile.exists() method is giving false in android, but it exists in memory, then you definitely have not given Write-external-storage Permission in the Manifest file of Your Project. Add this Permission in the Manifest of Your Project:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

来源：https://stackoverflow.com/questions/20437626/file-exists-returns-false-for-existing-file-in-android

标签

android

image

file

bitmap

decode