Android：用于SD卡已完全安装且可读的状态

public IntentFilter getIntentFilter() {
    IntentFilter intentFilter = new IntentFilter();
    intentFilter.addAction(Intent.ACTION_MEDIA_MOUNTED);
    intentFilter.addAction(Intent.ACTION_MEDIA_UNMOUNTED);
    intentFilter.addDataScheme(\"file\");
    return intentFilter;
}

@Override
public void onReceive(Context context, Intent intent) {
    String action = intent.getAction();
    if (Intent.ACTION_MEDIA_MOUNTED.equals(action)) {
        setMounted(true);
    } else if (Intent.ACTION_MEDIA_UNMOUNTED.equals(action)) {
        setMounted(false);
    }
}

private void setMounted(boolean isMounted) {
    if (isMounted) {
        doPerformQuery();
    }
}

registerReceiver(mountInstance, mountInstance.getIntentFilter());

Thread.sleep(5000);
doPerformQuery();