将文件(图像)从 cachedir 复制到 sd 卡-尊龙凯时

问题描述

我希望能够从 android 设备的内部缓存中移动或复制文件，并将其放入 sd 卡上的永久存储中.这是我目前所拥有的:

i want to be able to either move or copy a file from the internal cache of an android device and put this into permanent storage on the sd card. this is what i have so far:

public void onclicksavesecret(view v){
    file image = new file(getapplication().getcachedir()   "/image.png");
    file newimage = new file(environment.getexternalstoragedirectory()   "/image.png");
    toast.maketext(this, "image saved", 100).show();
}

推荐答案

/**
 * copy file from source to destination
 *
 * @param src source
 * @param dst destination
 * @throws java.io.ioexception in case of any problems
 */
void copyfile(file src, file dst) throws ioexception {
    filechannel inchannel = new fileinputstream(src).getchannel();
    filechannel outchannel = new fileoutputstream(dst).getchannel();
    try {
        inchannel.transferto(0, inchannel.size(), outchannel);
    } finally {
        if (inchannel != null)
            inchannel.close();
        if (outchannel != null)
            outchannel.close();
    }
}