Day6-DialogFragment & AlertDialog

Google 在官方文档中已经默认DialogFragment作为对话框的容器, 在其中填入AlertDialog或DatePickerDialog/ TimePickerDialog

• 优点: DialogFragment 能依靠 activity 的 onSaveInstance 和 FragmentManager 在横竖屏切换等 Activity 被杀死重建时重建对话框
• 缺点: TargetVersion 需定到 APILevel 11

用法

自定义布局

1. 创建布局文件

2. 继承DialogFragment,重写onCreagteView

   @Nullable
   @Override
   public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
       View inflate = inflater.inflate(R.layout.fragment_dialog, container);
       getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);//去掉默认标题
       return inflate;
   }
   

3. 在 activity中调用

   EditDialogFragment editDialogFragment = new EditDialogFragment();
   editDialogFragment.show(getFragmentManager(), "EditNameDialog");
   

默认的dialog格式, 按钮具体的样式跟着系统版本变化

1. 布局不需要添加按钮

2. 重写onCreateDialog
   onAttach 拿到上下文, 判断后强转成 Listener

   public class NoticeDialogFragment extends DialogFragment {
   
       /* The activity that creates an instance of this dialog fragment must
        * implement this interface in order to receive event callbacks.
        * Each method passes the DialogFragment in case the host needs to query it. */
       public interface NoticeDialogListener {
           public void onDialogPositiveClick(DialogFragment dialog);
           public void onDialogNegativeClick(DialogFragment dialog);
       }
   
       // Use this instance of the interface to deliver action events
       NoticeDialogListener mListener;
   
       // Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
       @Override
       public void onAttach(Context context) {
           super.onAttach(context);
           // Verify that the host activity implements the callback interface
           try {
               // Instantiate the NoticeDialogListener so we can send events to the host
               mListener = (NoticeDialogListener) context;
           } catch (ClassCastException e) {
               // The activity doesn't implement the interface, throw exception
               throw new ClassCastException(context.toString()
                       + " must implement NoticeDialogListener");
           }
       }
       ...
       @Override
       public Dialog onCreateDialog(Bundle savedInstanceState) {
              // Build the dialog and set up the button click handlers
              AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
              builder.setMessage(R.string.dialog_fire_missiles)
                     .setPositiveButton(R.string.fire, new DialogInterface.OnClickListener() {
                         public void onClick(DialogInterface dialog, int id) {
                             // Send the positive button event back to the host activity
                             mListener.onDialogPositiveClick(NoticeDialogFragment.this);
                         }
                     })
                     .setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
                         public void onClick(DialogInterface dialog, int id) {
                             // Send the negative button event back to the host activity
                             mListener.onDialogNegativeClick(NoticeDialogFragment.this);
                         }
                     });
              return builder.create();
          }
       }
   
   }
   

3. 调用

   DialogFragment newFragment = new FireMissilesDialogFragment();
   newFragment.show(getSupportFragmentManager(), "missiles");
   

4. 数据传递, 在 Activity 继承接口, 实现方法

   public class MainActivity extends FragmentActivity
                               implements NoticeDialogFragment.NoticeDialogListener{
         ...
   
         public void showNoticeDialog() {
             // Create an instance of the dialog fragment and show it
             DialogFragment dialog = new NoticeDialogFragment();
             dialog.show(getSupportFragmentManager(), "NoticeDialogFragment");
         }
   
         // The dialog fragment receives a reference to this Activity through the
         // Fragment.onAttach() callback, which it uses to call the following methods
         // defined by the NoticeDialogFragment.NoticeDialogListener interface
         @Override
         public void onDialogPositiveClick(DialogFragment dialog) {
             // User touched the dialog's positive button
             dialog.getdialog.findViewById...
             ...
         }
   
         @Override
         public void onDialogNegativeClick(DialogFragment dialog) {
             // User touched the dialog's negative button
             ...
         }
     }
   

清除对话框

手动调dismiss();

默认AlertDialog, 改button颜色

先show(), 之后再getButton

AlertDialog alertdialog = new AlertDialog.Builder(getActivity()).create();
       LayoutInflater layoutInflater = getActivity().getLayoutInflater();
       View view = layoutInflater.inflate(R.layout.fragment_dialog, null);
       alertdialog.setView(view);
       alertdialog.setButton(DialogInterface.BUTTON_NEGATIVE, "取消", new DialogInterface.OnClickListener() {
           @Override
           public void onClick(DialogInterface dialog, int which) {

           }
       });
       alertdialog.setButton(DialogInterface.BUTTON_POSITIVE, "ok", new DialogInterface.OnClickListener() {
           @Override
           public void onClick(DialogInterface dialog, int which) {

           }
       });
       alertdialog.show();
       Button button = alertdialog.getButton(alertdialog.BUTTON_POSITIVE);
       button.setTextColor(Color.parseColor("#00ffff"));
       return alertdialog;

不可点击

• 通用

  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
  //        this.setCancelable(false);
  }
  

• dialog的另一种方式

   public Dialog onCreateDialog(Bundle savedInstanceState) {  
      dialog.setCanceledOnTouchOutside(false);// 设置点击屏幕Dialog不消失
   }
  

参考

• CSDN | Android 官方推荐 : DialogFragment 创建对话框
• | [Android] Material 风格的 Dialog 的使用的第七条评论
• CSDN | 从源码看 AlertDialog.getButton(DialogInterface.BUTTON_POSITIVE) 为什么是 null