实现Android半透明Menu效果的开发实例

不知道大家是否用过天天动听，对于它界面上的半透明Menu效果，笔者感觉非常漂亮。下面是天天动听半透明Menu的截图，欣赏下吧：

       感觉还不错吧？那么如何实现这种半透明Menu效果呢？本文就重点讨论并给出这种Menu的具体代码实现过程。

       首先分析下实现这种半透明Menu所需做的工作，并进行合理分解：

       1.  利用Shaper设置一个半透明圆角背景。

       2.  定义Menu布局，主要就GridView，把图标都放在这个GridView。

       3.  Menu事件, 通过PopupWindow或者AlertDialog或者透明Activity显示到页面即可。

       4.  按钮的监听事件，实例中没加。需要的话自己在Adapter里加。

       比较简单，不多说了。

       半透明圆角背景xml：

XML/HTML代码

<?xml version="1.0" encoding="UTF-8"?>

<shape android:shape="rectangle">

    <solid android:color="#b4000000" />

    <stroke android:width="2.0dip" android:color="#b4ffffff" android:dashWidth="3.0dip" android:dashGap="0.0dip" />

    <padding android:left="7.0dip" android:top="7.0dip" android:right="7.0dip" android:bottom="7.0dip" />

    <corners android:radius="8.0dip" />

</shape>

        Menu布局：

XML/HTML代码

<?xml version="1.0" encoding="UTF-8"?>

<LinearLayout

        android:orientation="vertical"

        android:layout_width="wrap_content"

        android:layout_height="fill_parent">


        <GridView android:gravity="center"

                android:layout_gravity="center"

                android:id="@+id/menuGridChange"

                android:background="@drawable/menu_bg_frame"

                android:padding="5.0dip"

                android:layout_width="fill_parent"

                android:layout_height="wrap_content"

                android:horizontalSpacing="10.0dip"

                android:verticalSpacing="3.0dip"

                android:stretchMode="columnWidth"

                android:columnWidth="60.0dip"

                android:numColumns="auto_fit"/>


</LinearLayout>

       主要类：

Java代码

package com.yfz;


import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
import android.util.Log;
import android.view.ContextMenu;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ContextMenu.ContextMenuInfo;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.PopupWindow;
import android.widget.TextView;
import android.widget.LinearLayout.LayoutParams;

public class MenuTest extends Activity {

        private String TAG = this.getClass().getSimpleName();

        private int[] resArray = new int[] {
                R.drawable.icon_menu_addto, R.drawable.icon_menu_audioinfo,
                R.drawable.icon_menu_findlrc, R.drawable.icon_menu_scan
        };

        private String[] title = new String[]{
                "添加歌曲", "歌曲信息", "查找歌词", "搜索歌词"
        };

        private static boolean show_flag = false;
        private PopupWindow pw = null;

        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
        }

        @Override

        public boolean onCreateOptionsMenu(Menu menu) {
                Log.e(TAG, "------  onCreateOptionsMenu ------");
                //用AlertDialog弹出menu

//                View view = LayoutInflater.from(this).inflate(R.layout.menu, null);

//                GridView grid1 = (GridView)view.findViewById(R.id.menuGridChange);

//                grid1.setAdapter(new ImageAdapter(this));

//                Builder build = new AlertDialog.Builder(this);

//                build.setView(view);

//                build.show();

                LayoutInflater inflater = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

                View view = inflater.inflate(R.layout.menu, null);

                GridView grid1 = (GridView)view.findViewById(R.id.menuGridChange);

                grid1.setAdapter(new ImageAdapter(this));

                //用Popupwindow弹出menu
                pw = new PopupWindow(view,LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);

                //NND, 第一个参数， 必须找个View
                pw.showAtLocation(findViewById(R.id.tv), Gravity.CENTER, 0, 300);

                return true;
        }

        @Override

        public boolean onOptionsItemSelected(MenuItem item) {
                return super.onOptionsItemSelected(item);
       }

        public class ImageAdapter extends BaseAdapter {
                private Context context;

                public ImageAdapter(Context context) {
                        this.context = context;
                }

                @Override
                public int getCount() {
                        return resArray.length;
                }

                @Override
                public Object getItem(int arg0) {
                        return resArray[arg0];
                }

                @Override
                public long getItemId(int arg0) {
                        return arg0;
                }

                @Override
                public View getView(int arg0, View arg1, ViewGroup arg2) {
                        LinearLayout linear = new LinearLayout(context);

                        LinearLayout.LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

                        linear.setOrientation(LinearLayout.VERTICAL);

                        ImageView iv = new ImageView(context);

                        iv.setImageBitmap(((BitmapDrawable)context.getResources().getDrawable(resArray[arg0])).getBitmap());

                        LinearLayout.LayoutParams params2 = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

                        params2.gravity=Gravity.CENTER;

                        linear.addView(iv, params2);

                        TextView tv = new TextView(context);

                        tv.setText(title[arg0]);

                        LinearLayout.LayoutParams params3 = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

                        params3.gravity=Gravity.CENTER;

                        linear.addView(tv, params3);
                        return linear;
                }
        }
}

        到此，大家是不是觉得半透明Menu效果也是比较好实现的呢？可以根据自己的需要对此实例进行修改以求更美观好用。