Update DropdownMenu.java

src/net/micode/notes/ui/DropdownMenu.java

@@ -1,61 +1,47 @@
-/*
- * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *        http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package net.micode.notes.ui;
-
-import android.content.Context;
-import android.view.Menu;
-import android.view.MenuItem;
-import android.view.View;
-import android.view.View.OnClickListener;
-import android.widget.Button;
-import android.widget.PopupMenu;
-import android.widget.PopupMenu.OnMenuItemClickListener;
-
-import net.micode.notes.R;
-
-public class DropdownMenu {
-    private Button mButton;
-    private PopupMenu mPopupMenu;
-    private Menu mMenu;
-
-    public DropdownMenu(Context context, Button button, int menuId) {
-        mButton = button;
-        mButton.setBackgroundResource(R.drawable.dropdown_icon);
-        mPopupMenu = new PopupMenu(context, mButton);
-        mMenu = mPopupMenu.getMenu();
-        mPopupMenu.getMenuInflater().inflate(menuId, mMenu);
-        mButton.setOnClickListener(new OnClickListener() {
-            public void onClick(View v) {
-                mPopupMenu.show();
-            }
-        });
-    }
-
-    public void setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener) {
-        if (mPopupMenu != null) {
-            mPopupMenu.setOnMenuItemClickListener(listener);
-        }
-    }
-
-    public MenuItem findItem(int id) {
-        return mMenu.findItem(id);
-    }
-
-    public void setTitle(CharSequence title) {
-        mButton.setText(title);
-    }
-}
+// 声明一个公开的类DropdownMenu，此类属于net.micode.notes.ui包  
+public class DropdownMenu {  
+    // 声明一个私有变量mButton，类型为Button，表示一个按钮对象  
+    private Button mButton;  
+    // 声明一个私有变量mPopupMenu，类型为PopupMenu，表示一个弹出菜单对象  
+    private PopupMenu mPopupMenu;  
+    // 声明一个私有变量mMenu，类型为Menu，表示一个菜单对象  
+    private Menu mMenu;  
+  
+    // 声明一个公开的构造函数，接受三个参数：一个Context对象，一个Button对象和一个int型数据menuId  
+    public DropdownMenu(Context context, Button button, int menuId) {  
+        // 将传入的button赋值给mButton，即mButton就是我们操作的按钮对象  
+        mButton = button;  
+        // 为mButton设置背景资源，这里是设置成dropdown_icon这个资源  
+        mButton.setBackgroundResource(R.drawable.dropdown_icon);  
+        // 创建一个新的PopupMenu对象，传入上下文（context）和按钮（mButton）作为参数  
+        mPopupMenu = new PopupMenu(context, mButton);  
+        // 获取mPopupMenu的菜单对象并赋值给mMenu  
+        mMenu = mPopupMenu.getMenu();  
+        // 用传入的menuId来加载菜单项，并添加到mMenu中  
+        mPopupMenu.getMenuInflater().inflate(menuId, mMenu);  
+        // 为mButton设置一个点击事件监听器，当点击mButton时，会执行show方法，将弹出菜单显示出来  
+        mButton.setOnClickListener(new OnClickListener() {  
+            public void onClick(View v) {  
+                mPopupMenu.show();  
+            }  
+        });  
+    }  
+  
+    // 设置一个菜单项点击事件的监听器，传入一个OnMenuItemClickListener对象作为参数  
+    public void setOnDropdownMenuItemClickListener(OnMenuItemClickListener listener) {  
+        // 如果mPopupMenu不为null，就将监听器设置给mPopupMenu的菜单项点击事件监听器  
+        if (mPopupMenu != null) {  
+            mPopupMenu.setOnMenuItemClickListener(listener);  
+        }  
+    }  
+  
+    // 从mMenu中查找一个菜单项，并返回该菜单项，如果找到的话  
+    public MenuItem findItem(int id) {  
+        return mMenu.findItem(id);  
+    }  
+  
+    // 设置mButton的文本内容为传入的CharSequence对象title  
+    public void setTitle(CharSequence title) {  
+        mButton.setText(title);  
+    }  
+}