actionbar 에 아이콘 넣기, 클릭

res/ menu 에서
menu_main.xml  만들고!

<menu 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" tools:context=".Activity.DetailActivity">
    <item android:id="@+id/action_edit"
        android:icon="@drawable/edit_icon"
        android:title="edit"
        app:showAsAction="always"
        />
</menu>

activity.java 소스에 

@Override
public boolean onCreateOptionsMenu(Menu menu) {//action Button 생성
    // Inflate the menu items for use in the action bar
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu_main, menu);
    return super.onCreateOptionsMenu(menu);


}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle presses on the action bar items
    switch (item.getItemId()) {
        case R.id.action_edit:
            Toast toast = Toast.makeText(DetailActivity.this, "edit 버튼 눌림", Toast.LENGTH_SHORT );
            toast.show();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

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