Android_几种菜单
Android中的菜单有如下几种：
OptionMenu：选项菜单，android中最常见的菜单，通过Menu键来调用
SubMenu：子菜单，android中点击子菜单将弹出一个显示子菜单项的悬浮框， 子菜单不支持嵌套，即不能包括其他子菜单
ContextMenu：上下文菜单，通过长按某个视图组件后出现的菜单，该组件需注册上下文菜单
OptionMenu：
public boolean onCreateOptionsMenu(Menu menu)：调用OptionMenu，在这里完成菜单初始化
public boolean onOptionsItemSelected(MenuItem item)：菜单项被选中时触发，这里完成事件处理
public void onOptionsMenuClosed(Menu menu)：菜单关闭会调用该方法
public boolean onPrepareOptionsMenu(Menu menu)：选项菜单显示前会调用该方法， 可在这里进行菜单的调整(动态加载菜单列表)
public boolean onMenuOpened(int featureId, Menu menu)：选项菜单打开以后会调用这个方法
加载菜单的方式有两种，一种是直接通过编写菜单XML文件，然后调用： getMenuInflater().inflate(R.menu.menu_main, menu);加载菜单
或者通过代码动态添加，onCreateOptionsMenu的参数menu，调用add方法添加 菜单，add(菜单项的组号，ID，排序号，标题)，另外如果排序号是按添加顺序排序的话都填0即可
public class MainActivity extends AppCompatActivity {
//1.定义不同颜色的菜单项的标识:
final private int RED = 110;
final private int GREEN = 111;
final private int BLUE = 112;
final private int YELLOW = 113;
final private int GRAY= 114;
final private int CYAN= 115;
final private int BLACK= 116;
private TextView tv_test;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv_test = (TextView) findViewById(R.id.tv_test);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
menu.add(1,RED,4,"红色");
menu.add(1,GREEN,2,"绿色");
menu.add(1,BLUE,3,"蓝色");
menu.add(1,YELLOW,1,"黄色");
menu.add(1,GRAY,5,"灰色");
menu.add(1,CYAN,6,"蓝绿色");
menu.add(1,BLACK,7,"黑色");
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
switch (id){
case RED:
tv_test.setTextColor(Color.RED);
break;
case GREEN:
tv_test.setTextColor(Color.GREEN);
break;
case BLUE:
tv_test.setTextColor(Color.BLUE);
break;
case YELLOW:
tv_test.setTextColor(Color.YELLOW);
break;
case GRAY:
tv_test.setTextColor(Color.GRAY);
break;
case CYAN:
tv_test.setTextColor(Color.CYAN);
break;
case BLACK:
tv_test.setTextColor(Color.BLACK);
break;
}
return super.onOptionsItemSelected(item);
}}
ContextMenu
重写onCreateContextMenu()方法、为view组件注册上下文菜单，使用registerForContextMenu()方法,参数是View、重写onContextItemSelected()方法为菜单项指定事件监听器
menu_context.xml：
<?xml version="1.0" encoding="utf-8"?><menu xmlns:android="http://schemas.android.com/apk/res/android">
<!-- 定义一组单选按钮 -->
<!-- checkableBehavior的可选值由三个：single设置为单选，all为多选，none为普通选项 -->
<group android:checkableBehavior="none">
<item android:id="@+id/blue" android:title="@string/font_blue"/>
<item android:id="@+id/green" android:title="@string/font_green"/>
<item android:id="@+id/red" android:title="@string/font_red"/>
</group></menu>
接着我们在选项菜单的那个基础上，添加一个TextView，然后加上下面一些东西：
private TextView tv_context;
tv_context = (TextView) findViewById(R.id.tv_context);
registerForContextMenu(tv_context);
//重写与ContextMenu相关方法
@Override
//重写上下文菜单的创建方法
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenu.ContextMenuInfo menuInfo) {
MenuInflater inflator = new MenuInflater(this);
inflator.inflate(R.menu.menu_context, menu);
super.onCreateContextMenu(menu, v, menuInfo);
}
//上下文菜单被点击是触发该方法
@Override
public boolean onContextItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.blue:
tv_context.setTextColor(Color.BLUE);
break;
case R.id.green:
tv_context.setTextColor(Color.GREEN);
break;
case R.id.red:
tv_context.setTextColor(Color.RED);
break;
}
return true;
}
SubMenu(子菜单)
所谓的子菜单只是在<**item**>中又嵌套了一层<**menu**>而已
<?xml version="1.0" encoding="utf-8"?><menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/submenu" android:title="子菜单使用演示~">
<menu>
<group android:checkableBehavior = "none">
<item android:id="@+id/one" android:title = "子菜单一"/>
<item android:id="@+id/two" android:title = "子菜单二"/>
<item android:id="@+id/three" android:title = "子菜单三"/>
</group>
</menu>
</item></menu>
接着我们改下上面上下文菜单的两个方法的内容，换上下面的代码：
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenu.ContextMenuInfo menuInfo) {
//子菜单部分：
MenuInflater inflator = new MenuInflater(this);
inflator.inflate(R.menu.menu_sub, menu);
super.onCreateContextMenu(menu, v, menuInfo);}
public boolean onContextItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.one:
Toast.makeText(MainActivity.this,"你点击了子菜单一",Toast.LENGTH_SHORT).show();
break;
case R.id.two:
item.setCheckable(true);
Toast.makeText(MainActivity.this,"你点击了子菜单二",Toast.LENGTH_SHORT).show();
break;
case R.id.three:
Toast.makeText(MainActivity.this,"你点击了子菜单三",Toast.LENGTH_SHORT).show();
item.setCheckable(true);
break;
}
return true;}
Popupmenu见https://www.cnblogs.com/XiaoGao128/p/12240792.html
参考资料：菜鸟教程
