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

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    android:orientation="vertical"

    tools:context="com.hanqi.test5.UIActivity2">

    <Button

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="长按触发上下文菜单"

        android:id="@+id/bt_changan"/>

    <ProgressBar

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/pb_1"/>

    <ProgressBar

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        style="?android:attr/progressBarStyleHorizontal"

        android:max="100"

        android:progress="50"

        android:secondaryProgress="70"

        android:id="@+id/pb_2" />

   <ImageView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:src="@drawable/vipflower"

        android:id="@+id/iv_vip"/>

    <SeekBar

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:max="100"

        android:progress="100"

        android:id="@+id/sb_1"/><!--可拖动-->

</LinearLayout>

package com.hanqi.test5;

import android.app.Activity;

import android.os.Bundle;

import android.view.ContextMenu;

import android.view.Menu;

import android.view.MenuInflater;

import android.view.MenuItem;

import android.view.SubMenu;

import android.view.View;

import android.widget.Button;

import android.widget.ImageView;

import android.widget.ProgressBar;

import android.widget.SeekBar;

import android.widget.Toast;

public class UIActivity2 extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_ui2);

        Button bt_changan = (Button)findViewById(R.id.bt_changan);

        bt_changan.setOnCreateContextMenuListener(this);/*this代表当前Activity,实现了这个接口*/

        //进度条

        //有final时，生命周期长，不加final的话就只是当前方法的，加final可以延长生命周期，或者定义成员变量

        final ProgressBar pb_1 =(ProgressBar)findViewById(R.id.pb_1);

        final ProgressBar pb_2 =(ProgressBar)findViewById(R.id.pb_2);

        final SeekBar sb_1 =(SeekBar)findViewById(R.id.sb_1);

        sb_1.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

            //onProgressChanged进度条变化,进度改变就会触发

            @Override

            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

                //pb_2.setProgress(seekBar.getProgress());

                ImageView iv_vip = (ImageView)findViewById(R.id.iv_vip);

                //iv_vip.setAlpha(0.2f);透明度值是0-255

                iv_vip.setImageAlpha(progress * 255 /100);

            }

            //onStartTrackingTouch开始拖动

            @Override

            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            //onStopTrackingTouch停止拖动

            @Override

            public void onStopTrackingTouch(SeekBar seekBar) {

                pb_2.setProgress(seekBar.getProgress());

                if (seekBar.getProgress() == seekBar.getMax())

                {

                    //设置不可见

                    pb_1.setVisibility(View.GONE);

                    /*INVISIBLE不可见（占空间） VISIBLE可见 GONE不可见（不占空间）*/

                }

                else

                {

                    pb_1.setVisibility(View.VISIBLE);

                }

            }

        });

    }

    @Override

    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {

        menu.add(0,1,0,"添加");

        menu.add(0,2,1,"修改");

        menu.add(0, 3, 2, "删除");

        SubMenu m = menu.addSubMenu(0, 4, 3, "子菜单");

        m.add(0,41,0,"子菜单项1");

        m.add(0,42,1,"子菜单项2");

        m.add(0,43,2,"子菜单项3");

        m.add(0,44,3,"子菜单项4");

//        MenuInflater mi =getMenuInflater();

//        mi.inflate(R.menu.mymenu,menu);

        super.onCreateContextMenu(menu, v, menuInfo);

    }

    @Override

    public boolean onContextItemSelected(MenuItem item) {

        switch (item.getItemId())

        {

            case R.id.it_2:

                Toast.makeText(UIActivity2.this, "触发了添加1功能", Toast.LENGTH_SHORT).show();

                break;

            case R.id.it_1:

                Toast.makeText(UIActivity2.this, "触发了删除1功能", Toast.LENGTH_SHORT).show();

                break;

        }

        return super.onContextItemSelected(item);

    }

    @Override

    //重写  创建选项菜单的方法

    public boolean onCreateOptionsMenu(Menu menu) {

        //添加菜单项

        //纯编码方式

//        menu.add(0,1,0,"添加");

//        menu.add(0,2,2,"删除");

//        menu.add(0,3,1,"修改");

        //加载菜单文件方式

        //1.获取菜单加载器

        MenuInflater mi =getMenuInflater();

        mi.inflate(R.menu.mymenu,menu);

        return super.onCreateOptionsMenu(menu);

    }

    @Override

    public boolean onOptionsItemSelected(MenuItem item) {

        //Toast.makeText(UIActivity2.this, "选中的菜单项是" + item.getTitle(), Toast.LENGTH_SHORT).show();

        //根据菜单项的不同响应不同功能

        switch (item.getItemId())

        {

            case 1:

                Toast.makeText(UIActivity2.this, "触发了添加功能", Toast.LENGTH_SHORT).show();

                break;

            case 2:

                Toast.makeText(UIActivity2.this, "触发了删除功能", Toast.LENGTH_SHORT).show();

                break;

            case 3:

                Toast.makeText(UIActivity2.this, "触发了修改功能", Toast.LENGTH_SHORT).show();

                break;

            case R.id.it_2:

                Toast.makeText(UIActivity2.this, "触发了添加1功能", Toast.LENGTH_SHORT).show();

                break;

            case R.id.it_1:

                Toast.makeText(UIActivity2.this, "触发了删除1功能", Toast.LENGTH_SHORT).show();

                break;

        }

        return super.onOptionsItemSelected(item);

    }

}