实施 onClick on 子菜单以开始新活动

Question

I'm building an app which has menu item in toolbar, i have created submenu for one menu ie whose id is 'cloud'. I would like to implement onclick on each submenu when click will open different activity.

Here is the menu.xml file

 <?xml version="1.0" encoding="utf-8"?> <menu xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto"> <item android:id="@+id/action_refresh" app:showAsAction="ifRoom" android:title="Refresh" android:icon="@drawable/ic_loop_black_24dp"></item> <item android:id="@+id/notes" app:showAsAction="ifRoom" android:title="Refresh" android:icon="@drawable/ic_event_note_black_24dp"></item> <item android:id="@+id/cloud" app:showAsAction="ifRoom" android:title="Refresh" android:icon="@drawable/ic_cloud_upload_blackt_24dp"> <menu> <group android:checkableBehavior="single"> <item android:id="@+id/imageee" android:title="Image Upload" android:orderInCategory="100" app:showAsAction="ifRoom" /> <item android:id="@+id/pdfff" android:title="Pdf Upload" android:orderInCategory="100" app:showAsAction="never"/> </group> </menu> </item> </menu>

Here is the Mainactivity file

 @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); mymenu = menu; return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch(item.getItemId()) { case R.id.action_refresh: Intent intent = new Intent(MainActivity.this, UpdateService.class); startService(intent); } return true; case R.id.notes:{ Intent activity_weather = new Intent(this,Physics.class); startActivity(activity_weather); } return true; case R.id.cloud:{ } return true; } return super.onOptionsItemSelected(item); }

I looked for answer and tried on my own but I have no idea how to achieve this.

Any help is appreciated.

Thank you in advance.

Answer 1

I have a solution for you:

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_refresh:
            // TODO:
            toast("refresh");
            return true;
        case R.id.notes:
            // TODO:
            toast("notes");
            return true;
        case R.id.imageee:
            // TODO: Start your image upload
            toast("imageee");
            return true;
        case R.id.pdfff:
            // TODO: Start your PDF upload
            toast("pdfff");
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

public void toast(String message) {
    Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
}

I write toast method to show a toast when users click on an item on menu or sub menu. Please remove //TODO: line and add your code for each case there.

Answer 2

I don't think you want to have

android:checkableBehavior="single"

set on your submenu. This behaviour is only useful if you just want to capture the choice (or choices) in the menu item, but not if you actually want to react (ie: do something) when the user selects a submenu item.

Based on your question, it sounds like you want to launch another Activity when the user selects one of these submenu items. To do that just add those menu items to the switch statement in onOptionsItemSelected() :

case R.id.imageee:
    Intent imageIntent = new Intent(this, Upload.class);
    startActivity(imageIntent);
    return true;
case R.id.pdfff:
    Intent pdfIntent = new Intent(this, Pdf.class);
    startActivity(pdfIntent);
    return true;

Answer 3

Another interesting solution could be:

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    Intent intent = new Intent();
    switch (item.getItemId()) {
        case R.id.action_refresh:
            intent.setClass(this, UpdateService.class);
            break;
        case R.id.notes:
            intent.setClass(this, Physics.class);
            break;
        case R.id.cloud:
            intent = null;           
            break
        case R.id.imageee:
            // TODO set intent class
            break;
        case R.id.pdfff:
            // TODO set intent class
            break;
     }
// If the selected item is the one that opens the submenu does not try to start the 
// activity avoiding throwing null pointer exception and consequently opens the submenu
     if (!(intent == null))  
         startActivity(intent);
     return super.onOptionsItemSelected(item);
}

That way you avoid having to have multiple times, in all cases the same call to the method.

startActivity()

Saving lines of code. It is even more advantageous if you decide to add more items to the menu.