Android 方法的签名不正确？

我是初学者。 这些代码仅在android 6及更高版本上运行。 代码在带有6个警告的情况下运行良好，但我希望在菜单_Main.xml中去掉这6个警告6行，例如带有onClick=itemClick的行

我能做些什么来摆脱这些警告？请帮助我

MainActivity.java activity_main.xml menu_Main.xml strings.xml

---

我不认为如果你在菜单中，依赖onClick属性是合适的，但也许我错了

无论如何，您应该删除XML中的onClick属性并依赖于

package com.example.sky.my13application;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return super.onCreateOptionsMenu(menu);
    }  
    public boolean itemClick(MenuItem item){
        Toast.makeText(this,item.getTitle() ,Toast.LENGTH_LONG).show();
        return true;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
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"
tools:context="com.example.sky.my13application.MainActivity">

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:android="http://schemas.android.com/apk/res/android">

       <item android:title="@string/app_name1"
             android:onClick="itemClick"
             />
       <item android:title="@string/app_name2"
             android:onClick="itemClick"
             />
       <item android:title="@string/app_name3"
             android:onClick="itemClick"
             >
       <menu>
            <item android:title="@string/app_name4"
                  android:onClick="itemClick"
            />
            <item android:title="@string/app_name5"
                  android:onClick="itemClick"
             />
       </menu>
    </item>
</menu>

<resources>
    <string name="app_name">My13Application</string>
    <string name="app_name1">item1</string>
    <string name="app_name2">item2</string>
    <string name="app_name3">sub menu</string>
    <string name="app_name4">sub item1</string>
    <string name="app_name5">sub item2</string>
</resources>

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle item selection
    switch (item.getItemId()) {
        case R.id.button1:
            action1();
            return true;
        case R.id.button2:
            action2();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}