MainActivity.java 文件源码

@Override
public void onBackPressed() {
    if (mPhotoPaths.size() > 0) {
        AlertDialogWrapper.Builder builder = new AlertDialogWrapper.Builder(this);
        builder.setTitle(R.string.confirm_exit);
        builder.setMessage(R.string.exit_message);
        builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                MainActivity.super.onBackPressed();
            }
        });
        builder.setNegativeButton(android.R.string.cancel, null);
        builder.show();
    } else {
        super.onBackPressed();
    }
}