Menu菜单

选项菜单

1.菜单的生命周期

* onCreateOptionsMenu()   选项菜单创建时调用(启动Activity时调用 只调用1次)
* onPrepareOptionsMenu()  选项菜单准备时调用(点击Menu键时调用 调用多次)
* onOptionsItemSelected() 选项菜单项选中时调用
* onOptionsMenuClosed()   选项菜单关闭时

2.onCreateOptionsMenu()方法

在onCreateOptionsMenu()中添加菜单项，建议使用

menu.add(1, Menu.FIRST, Menu.FIRST, "xx");
menu.add(1, Menu.FIRST+1, Menu.FIRST+1, "xx");
menu.add(1, Menu.FIRST+2, Menu.FIRST+2, "xx");

添加子菜单

SubMenu sub = menu.addSubMenu(1, Menu.FIRST+4, Menu.FIRST+4, "xxx");

在子菜单中添加菜单项

sub.add(2, Menu.FIRST+5, Menu.FIRST+5, "xx");
sub.add(2, Menu.FIRST+6, Menu.FIRST+6, "xx");
sub.add(2, Menu.FIRST+7, Menu.FIRST+7, "xx");

3.onOptionsItemSelected()方法

在onOptionsItemSelected()中进行菜单项选中事件的操作 比如

int id = item.getItemId();
switch(id) {
case Menu.FIRST:
    ...
    break;
case Menu.FIRST+1:
    ...
    break;
}

例：

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    menu.add(1, Menu.FIRST, Menu.FIRST, "红");
    menu.add(1, Menu.FIRST + 1, Menu.FIRST + 1, "黄");// 菜单项
    menu.add(1, Menu.FIRST + 2, Menu.FIRST + 2, "蓝"); // 菜单项
    menu.add(1, Menu.FIRST + 3, Menu.FIRST + 3, "绿"); // 菜单项
    // 添加子菜单
    SubMenu sub = menu.addSubMenu(1, Menu.FIRST + 4, Menu.FIRST + 4, "更多"); // 子菜单
    sub.add(2, Menu.FIRST + 5, Menu.FIRST + 5, "其他1");
    sub.add(2, Menu.FIRST + 6, Menu.FIRST + 6, "其他2");
    sub.add(2, Menu.FIRST + 7, Menu.FIRST + 7, "其他3");

    // Inflate the menu; this adds items to the action bar if it is present.
    //MenuInflater inflater = getMenuInflater();
    //inflater.inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    return super.onPrepareOptionsMenu(menu);
}

@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 Menu.FIRST:
        textview.setTextColor(Color.RED);
        break;
    case Menu.FIRST + 1:
        textview.setTextColor(Color.YELLOW);
        break;
    case Menu.FIRST + 2:
        textview.setTextColor(Color.BLUE);
        break;
    case Menu.FIRST + 3:
        textview.setTextColor(Color.GREEN);
        break;
    case Menu.FIRST + 5:
        textview.setTextColor(Color.CYAN);
        break;
    case Menu.FIRST + 6:
        textview.setTextColor(Color.GRAY);
        break;
    case Menu.FIRST + 7:
        textview.setTextColor(Color.MAGENTA);
        break;
    }
    return super.onOptionsItemSelected(item);
}

@Override
public void onOptionsMenuClosed(Menu menu) {
    super.onOptionsMenuClosed(menu);
}

上下文菜单

第一种方式

1.生命周期

onCreateContextMenu();//创建菜单时调用
onContextItemSelected();//选中上下文时调用
onContextMenuClosed();//关闭菜单时调用

例：

registerForContextMenu(textview);
    
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
    switch (v.getId()) {
    case R.id.textview:
        menu.add(3, Menu.FIRST+5, Menu.FIRST+5, "红");
        menu.add(3, Menu.FIRST+6, Menu.FIRST+6, "黄");
        SubMenu submenu = menu.addSubMenu(3, Menu.FIRST+7, Menu.FIRST+7, "其他");
        submenu.add(4, Menu.FIRST+8, Menu.FIRST+8, "蓝");
        submenu.add(4, Menu.FIRST+9, Menu.FIRST+9, "绿");
        break;

    
    }
    super.onCreateContextMenu(menu, v, menuInfo);
}


@Override
public boolean onContextItemSelected(MenuItem item) {
    int id = item.getItemId();
    switch (id) {
    case Menu.FIRST+5:
        textview.setBackgroundColor(Color.RED);
        break;
    case Menu.FIRST+6:
        textview.setBackgroundColor(Color.YELLOW);
        break;
    case Menu.FIRST+8:
        textview.setBackgroundColor(Color.BLUE);
        break;
    case Menu.FIRST+9:
        textview.setBackgroundColor(Color.GREEN);
        break;
    }
    return super.onContextItemSelected(item);
}


@Override
public void onContextMenuClosed(Menu menu) {
    // TODO Auto-generated method stub
    super.onContextMenuClosed(menu);
}

 第二种方式

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/m1"
        android:title="m1">
        <menu>
            <item
                android:id="@+id/m5"
                android:title="m5"></item>
        </menu>
    </item>
    <item
        android:id="@+id/m2"
        android:title="m2"></item>
    <item
        android:id="@+id/m3"
        android:title="3"></item>
    <item
        android:id="@+id/m4"
        android:title="m4"></item>
</menu>

public class MainActivity extends AppCompatActivity {

    private ListView listview;
    private List<String> list;
    private ArrayAdapter<String> adapter;
    private int position;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listview = (ListView) findViewById(R.id.listview);
        initData();
        adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,list);
        listview.setAdapter(adapter);
        registerForContextMenu(listview);
    }

    private void initData() {
        list = new ArrayList<>();
        for (int i = 0; i < 30; i++) {
            list.add("王者--"+i);
        }
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
        super.onCreateContextMenu(menu, v, menuInfo);
        getMenuInflater().inflate(R.menu.menu,menu);
    }

    @Override
    public boolean onContextItemSelected(MenuItem item) {
        AdapterView.AdapterContextMenuInfo menuInfo = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
        if(menuInfo!=null){
            position = menuInfo.position;
        }
        switch (item.getItemId()){
            case 1:
                list.add(0,"王者");
                break;
            case 2:
                list.set(position,"王者归来");
                adapter.notifyDataSetChanged();
                break;
            case 3:
                list.remove(position);
                adapter.notifyDataSetChanged();
                break;
        }
        return super.onContextItemSelected(item);
    }
}