Android_(菜单)选项菜单

川长思鸟来 2021-12-12 23:43 315阅读 0赞

Android系统中菜单分为Options Menu、Context Menu、Sub Men三种

Options Menu和Context Menu属于一级菜单

Sub Menu属于Options Menu和Context Menu的子菜单

Sub Menu下不能再添加菜单，Android最多只能支持两级菜单

选项菜单(Options Menu)在当前Activity中按下菜单键就会显示

Android4.0一下默认在屏幕底部(我也不知道我的为什么默认是在右上角！！！)

常用以下方法使用 选项菜单

onCreateOptionsMenu(Menu menu)：创建菜单，会在菜单第一次显示时调用。

onPrepareOnptionsMenu(Menu menu)： 准备显示菜单，菜单每次显示前调用。

onOptionsItemSelected(MenuItem item)：菜单项被选中后处理选中的菜单项。

onMenuOpened(int featureId,Menu menu)：菜单被打开的事件。

onOptionsMenuClosed(Menu menu)：菜单被关闭的事件。

openOptionsMenu()：调用打开菜单

closeOptionsMenu()：调用关闭菜单

运行截图：

![1282839-20180708213302728-1427810805.png][]![1282839-20180708213304933-880326163.png][]![1282839-20180708213308876-954021893.png][]

程序结构：

![1282839-20180708213958546-1038614333.png][]

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][]

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        tools:context="com.example.asus.gary_03.MainActivity">
    
    
        <EditText
            android:id="@+id/txt"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:hint="输入文字"
            android:editable="false"
            android:inputType="textPersonName" />
    </LinearLayout>

activity\_main.xml

![ContractedBlock.gif][] ![ExpandedBlockStart.gif][]

package com.example.asus.gary_03;
    
    import android.graphics.Color;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.SubMenu;
    import android.widget.EditText;
    import android.widget.Toast;
    
    public class MainActivity extends AppCompatActivity {
    
        //定义字体大小菜单项的标识
        final int FONT_10 = 0x111;
        final int FONT_12 = 0x112;
        final int FONT_14 = 0x113;
        final int FONT_16 = 0x114;
        final int FONT_18 = 0x115;
        //定义普通菜单项的标识
        final int PLAIN_ITEM = 0x11b;
        //定义字体颜色菜单项的标识
        final int FONT_RED = 0x116;
        final int FONT_BLUE = 0x117;
        final int FONT_GREEN = 0x118;
        private EditText edit;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            edit = (EditText)findViewById(R.id.txt);
        }
    
        public boolean onCreateOptionsMenu(Menu menu) {
            //向menu中添加字体大小的子菜单
            SubMenu fontMenu = menu.addSubMenu("字体大小");
            //设置菜单的图标
            fontMenu.setIcon(android.R.drawable.btn_plus);
            //设置菜单头的图标
            fontMenu.setHeaderIcon(android.R.drawable.btn_default);
            //设置菜单头的标题
            fontMenu.setHeaderTitle("选择字体大小");
            fontMenu.add(0,FONT_10,0,"10号字体");
            fontMenu.add(0,FONT_12,0,"12号字体");
            fontMenu.add(0,FONT_14,0,"14号字体");
            fontMenu.add(0,FONT_16,0,"16号字体");
            fontMenu.add(0,FONT_18,0,"18号字体");
            //向menu中添加普通菜单项
            menu.add(0,PLAIN_ITEM,0,"普通菜单项");
            //向menu中添加文字颜色的子菜单
            SubMenu colorMenu = menu.addSubMenu("字体的颜色");
            colorMenu.setIcon(android.R.drawable.btn_plus);
            colorMenu.setHeaderIcon(android.R.drawable.btn_default);
            colorMenu.setHeaderTitle("选择文字的颜色");
            colorMenu.add(0,FONT_RED,0,"红色");
            colorMenu.add(0,FONT_GREEN,0,"绿色");
            colorMenu.add(0,FONT_BLUE,0,"蓝色");
    
            return super.onCreateOptionsMenu(menu);
        }
    
        public boolean onOptionsItemSelected(MenuItem mi)
        {
            switch(mi.getItemId())
            {
                case FONT_10:
                    edit.setTextSize(10*2);
                    break;
                case FONT_12:
                    edit.setTextSize(12*2);
                    break;
                case FONT_14:
                    edit.setTextSize(14*2);
                    break;
                case FONT_16:
                    edit.setTextSize(16*2);
                    break;
                case FONT_18:
                    edit.setTextSize(18*2);
                    break;
                case FONT_RED:
                    edit.setTextColor(Color.RED);
                    break;
                case FONT_GREEN:
                    edit.setTextColor(Color.GREEN);
                    break;
                case FONT_BLUE:
                    edit.setTextColor(Color.BLUE);
                    break;
                case PLAIN_ITEM:
                    Toast toast = Toast.makeText(MainActivity.this,"单击普通菜单项",Toast.LENGTH_SHORT);
                    toast.show();
                    break;
            }
            return true;
        }
    
    }

MainActivity

一、界面布局

只有一个EditText用来显示测试的内容

二、实现程序

1、向menu中添加字体大小的子菜单

fontMenu.setHeaderTitle("选择字体大小");
            fontMenu.add(0,FONT_10,0,"10号字体");
            fontMenu.add(0,FONT_12,0,"12号字体");
            fontMenu.add(0,FONT_14,0,"14号字体");
            fontMenu.add(0,FONT_16,0,"16号字体");
            fontMenu.add(0,FONT_18,0,"18号字体");
            //向menu中添加普通菜单项
            menu.add(0,PLAIN_ITEM,0,"普通菜单项");
            //向menu中添加文字颜色的子菜单
            SubMenu colorMenu = menu.addSubMenu("字体的颜色");
            colorMenu.setIcon(android.R.drawable.btn_plus);
            colorMenu.setHeaderIcon(android.R.drawable.btn_default);
            colorMenu.setHeaderTitle("选择文字的颜色");
            colorMenu.add(0,FONT_RED,0,"红色");
            colorMenu.add(0,FONT_GREEN,0,"绿色");
            colorMenu.add(0,FONT_BLUE,0,"蓝色");

2、实现对子菜单项的选择

onOptionsItemSelected(MenuItem item)：菜单项被选中后处理选中的菜单项。

public boolean onOptionsItemSelected(MenuItem mi)
        {
            switch(mi.getItemId())
            {
                case FONT_10:
                    edit.setTextSize(10*2);
                    break;
                case FONT_12:
                    edit.setTextSize(12*2);
                    break;
                case FONT_14:
                    edit.setTextSize(14*2);
                    break;
                case FONT_16:
                    edit.setTextSize(16*2);
                    break;
                case FONT_18:
                    edit.setTextSize(18*2);
                    break;
                case FONT_RED:
                    edit.setTextColor(Color.RED);
                    break;
                case FONT_GREEN:
                    edit.setTextColor(Color.GREEN);
                    break;
                case FONT_BLUE:
                    edit.setTextColor(Color.BLUE);
                    break;
                case PLAIN_ITEM:
                    Toast toast = Toast.makeText(MainActivity.this,"单击普通菜单项",Toast.LENGTH_SHORT);
                    toast.show();
                    break;
            }
            return true;
        }

转载于:https://www.cnblogs.com/1138720556Gary/p/9281417.html

[1282839-20180708213302728-1427810805.png]: https://images2018.cnblogs.com/blog/1282839/201807/1282839-20180708213302728-1427810805.png
[1282839-20180708213304933-880326163.png]: https://images2018.cnblogs.com/blog/1282839/201807/1282839-20180708213304933-880326163.png
[1282839-20180708213308876-954021893.png]: /images/20211210/2f0457a697b54685978898609e4c136d.png
[1282839-20180708213958546-1038614333.png]: /images/20211210/89b1d62a74a045e09eb9155c8c8f35fd.png
[ContractedBlock.gif]: https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif
[ExpandedBlockStart.gif]: /images/20211210/4ff150ed9b334b3b855657a71dacd541.png