// 显示Dialog
dialog.show();

// 显示软键盘
SoftInputUtils.showSoftInput(activity);

// 第一种，如果软键盘在窗口上已经显示，则隐藏，反之则显示
InputMethodManager inputMethodManager = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
inputMethodManager.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);

// 第二种，强制显示软键盘，view为当前的输入框对象
inputMethodManager.showSoftInput(view,InputMethodManager.SHOW_FORCED); 

/**
 * 发送显示Dialog的消息
 */
private void sendShowMessage() {
  if (mShowMessage != null) {
    // Obtain a new message so this dialog can be re-used
    Message.obtain(mShowMessage).sendToTarget();
  }
}


/**
 * 接收显示或隐藏Dialog的消息
 */
private static final class ListenersHandler extends Handler {
  private WeakReference<DialogInterface> mDialog;

  public ListenersHandler(Dialog dialog) {
    mDialog = new WeakReference<DialogInterface>(dialog);
  }

  @Override
  public void handleMessage(Message msg) {
    switch (msg.what) {
      case DISMISS:
        ((OnDismissListener) msg.obj).onDismiss(mDialog.get());
        break;
      case CANCEL:
        ((OnCancelListener) msg.obj).onCancel(mDialog.get());
        break;
      case SHOW:
        ((OnShowListener) msg.obj).onShow(mDialog.get());
        break;
    }
  }
}

new Thread() {
  @Override
  public void run() {
    super.run();
    activity.runOnUiThread(new Runnable() {
      @Override
      public void run() {
        SoftInputUtils.showSoftInput(activity);
      }
    });
  }
}.start();

public class DialogUtils {

  private static Dialog dialog;

  /**
   * Dialog提示框消失方法
   */
  public static void dialogDismiss() {
    if (isDialogShowing()) {
      dialog.dismiss();
      dialog = null;
    }
  }

  /**
   * Dialog提示框是否正在运行
   *
   * @return Dialog提示框是否正在运行
   */
  public static boolean isDialogShowing() {
    return dialog != null && dialog.isShowing();
  }


  /**
   * 创建Dialog提示框
   *
   * @param context 上下文
   */
  private static void createDialog(Context context) {
    dialogDismiss();
    dialog = new Dialog(context, R.style.SampleTheme);
    dialog.setContentView(R.layout.layout_dialog);
    // 点击弹窗外区域，弹窗不消失
    dialog.setCanceledOnTouchOutside(false);
  }

  /**
   * 显示确认安全码提示框
   *
   * @param activity       当前Activity
   * @param dialogOnClickListener 确定按钮点击事件
   */
  public static void showSecurityCodeInputDialog(final Activity activity,
                          final DialogOnClickListener dialogOnClickListener) {
    createDialog(activity);

    ImageView ivClose = (ImageView) dialog.findViewById(R.id.iv_close);
    final GridPasswordView gpvCode = (GridPasswordView) dialog.findViewById(R.id.gpv_code);
    Button btnOk = (Button) dialog.findViewById(R.id.btn_ok);

    ivClose.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        dialogDismiss();
      }
    });
    btnOk.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        String code = gpvCode.getPassWord();
        dialogOnClickListener.onClick(code);
      }
    });

    dialog.setOnShowListener(new DialogInterface.OnShowListener() {
      @Override
      public void onShow(DialogInterface dialog) {
        // 获取焦点
        gpvCode.requestFocus();
        // 显示软键盘
        SoftInputUtils.showSoftInput(activity);
      }
    });
    dialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
      @Override
      public void onDismiss(DialogInterface dialog) {
        // 隐藏软键盘
        SoftInputUtils.hideSoftInput(activity);
      }
    });

    dialog.show();
  }

  public interface DialogOnClickListener {
    /**
     * 点击事件
     *
     * @param str 回调参数
     */
    public void onClick(String str);
  }
}

public class SoftInputUtils {

  /**
   * 显示软键盘，Dialog使用
   *
   * @param activity 当前Activity
   */
  public static void showSoftInput(Activity activity) {
    InputMethodManager inputMethodManager =
        (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
    inputMethodManager.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);
  }

  /**
   * 隐藏软键盘
   *
   * @param activity 当前Activity
   */
  public static void hideSoftInput(Activity activity) {
    InputMethodManager inputMethodManager =
        (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
    inputMethodManager.hideSoftInputFromWindow(
        activity.getWindow().getDecorView().getWindowToken(), 0);
  }
}

DialogUtils.showSecurityCodeInputDialog(this, new DialogUtils.DialogOnClickListener() {
  @Override
  public void onClick(String str) {
    Toast.makeText(MainActivity.this, str, Toast.LENGTH_SHORT).show();
    DialogUtils.dialogDismiss();
  }
});