错误一：requestFeature() must be called before adding content

解决：setContentView(view)的执行需要在dialog.show()执行之后

但是后来发现，并不需要这样。以下实现方式已修正。

简单自定义：

public class CountDownDialog extends AlertDialog {

    /**
     * 上下文
     */
    private Context mContext;
    /**
     * 布局文件
     */
    private View mRootView;

    /**
     * 提示框标题
     */
    private String mTitle;
    /**
     * 提示框内容
     */
    private String mContent;
    /**
     * 提交/确定 按钮 这里不使用button 没有必要
     */
    private Button mDialogCommit,mDialogCancel;
    /**
     * 秒
     */
    private int mCount;

    /**
     * handler 标志位
     */
    private static final int DEFAULT_MSG = 0;

    @SuppressLint("HandlerLeak")
    private Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case DEFAULT_MSG:
                    String count = String.format(mContext.getString(R.string.dialog_yes_num), mCount--);
                    mDialogCommit.setText(count);
                    if (mCount < 0) {
                        onCommit();
                        dismiss();
                    } else {
                        sendEmptyMessageDelayed(DEFAULT_MSG, 1000);
                    }
                    break;
                default:
                    break;
            }


        }
    };

    public CountDownDialog(Context context, String title, String content, int countDown) {
        super(context);
        this.mContext = context;
        mTitle = title;
        mContent = content;
        mCount = countDown;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Window window = getWindow();
        WindowManager.LayoutParams attributes = window.getAttributes();
        //设置宽度
        attributes.width = 600;
        attributes.height = WRAP_CONTENT;
        //设置位置
//        attributes.x=600;
//        attributes.y=800;
        window.setAttributes(attributes);

        mRootView = LayoutInflater.from(mContext).inflate(R.layout.dialog_countdown_yes, null);

        TextView dialogTitle = (TextView) mRootView.findViewById(R.id.dialog_title);
        dialogTitle.setText(mTitle);
        TextView textContent = (TextView) mRootView.findViewById(R.id.text_content);
        if (mContent != null && !mContent.isEmpty()) {
            textContent.setText(mContent);
        } else {
            textContent.setVisibility(View.GONE);
        }
        mDialogCommit = (Button) mRootView.findViewById(R.id.dialog_commit);

        mDialogCommit.setOnClickListener(view -> onCommit());

        if (mCount != 0 && mCount > 0) {
            mHandler.sendEmptyMessageDelayed(DEFAULT_MSG, 1000);
        }

        mDialogCancel = (Button) mRootView.findViewById(R.id.dialog_cancel);
        mDialogCancel.setOnClickListener(v -> {
            onCancel();
            dismiss();
        });

        this.setOnCancelListener(dialogInterface -> onCancel());
        
        setContentView(mRootView);
    }

    /**
     * 取消与退出时的公共操作
     */
    private void onCancel() {
        if (mCustomOnCancelListener != null) {
            mCustomOnCancelListener.onCancel();
        }
        mHandler.removeCallbacksAndMessages(null);
    }

    private void onCommit() {
        if (mCustomOnCommitListener != null) {
            mCustomOnCommitListener.onCommit();
        }
        mHandler.removeCallbacksAndMessages(null);
        dismiss();
    }


    //确定的回调

    public interface CustomOnCommitListener {
        /**
         * 确定
         */
        void onCommit();
    }

    private CustomOnCommitListener mCustomOnCommitListener;

    public void setCustomOnCommitListener(CustomOnCommitListener customOnCommitListener) {
        this.mCustomOnCommitListener = customOnCommitListener;
    }

    //取消的回调

    public interface CustomOnCancelListener {
        /**
         * 退出
         */
        void onCancel();
    }

    private CustomOnCancelListener mCustomOnCancelListener;

    public void setCustomOnCancelListener(CustomOnCancelListener customOnCancelListener) {
        this.mCustomOnCancelListener = customOnCancelListener;
    }
}

String.xml

<string name=”dialog_yes”>是(%1$d)</string>

布局就不上了，自行设计即可。

用的时候：

CountDownDialog dialog = new CountDownDialog(mContext, title, content, 10);
dialog.show();
dialog.setCustomOnCommitListener(new CountDownDialog.CustomOnCommitListener() {
    @Override
    public void onCommit() {
        //TODO
        Toast.makeText(mContext, "关机中", Toast.LENGTH_SHORT).show();
        dialog.dismiss();
    }
});

总结：

设置宽高：

 Window window = getWindow();
        WindowManager.LayoutParams attributes = window.getAttributes();
        //设置宽度
        attributes.width = 600;
        attributes.height = WRAP_CONTENT;
        window.setAttributes(attributes);

设置位置：

 Window window = getWindow();
        WindowManager.LayoutParams attributes = window.getAttributes();
        //设置位置
        attributes.x=600;
        attributes.y=800;
        window.setAttributes(attributes);

宽高在xml中设置是不生效的，所以需要在代码中进行设置。

另外还有其他方式：如直接使用生成的对象来设置宽高：

dialog.getWindow().setLayout(400, 500)