Change icons in ActionBar dynamically

Question

I have an Activity which has an ActionBar but I need to change the icons on the ActionBar dynamically, I have a pause and a <

Answer 1

You'll have to save off a reference to the MenuItem after doing the inflation. So something like the following:

public boolean onCreateOptionsMenu( Menu menu ) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate( R.menu.actionbarlogic, menu );
    playMenu = menu.findItem(R.id.playMenu);
    updatePlayStatus();
    return menu;
}

public void updatePlayStatus() {
    if( playService.isConnected() ) {
        playService.isPlaying() ? playMenu.setIcon(R.drawable.pause) : playMenu.setIcon(R.drawable.play);
    }
}

Then you can refer to the playMenu anytime. So you can modify the item as say your player finishes playing and should go back to a play icon.

Answer 2

Instead of removing them, you could just hide the button you don't want displayed.

For example:

private boolean isPlaying;
MenuItem mPlayMenuItem;
MenuItem mPauseMenuItem;

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

    mPlayMenuItem = menu.findItem(R.id.action_play);
    mPauseMenuItem = menu.findItem(R.id.action_pause);

    return super.onCreateOptionsMenu(menu);

}

@Override
public boolean onOptionsItemSelected(MenuItem item) {

    switch (item.getItemId()) {
        case R.id.action_play:
            isPlaying = true;
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                this.invalidateOptionsMenu();
            }
            return true;
        case R.id.action_pause:
            isPlaying = false;
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
                this.invalidateOptionsMenu();
            }
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}


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

    if (isPlaying) {
        mPlayMenuItem.setVisible(false); // hide play button
        mPauseMenuItem.setVisible(true); // show the pause button
    } else if (!isPlaying) {
        mPlayMenuItem.setVisible(true); // show play button
        mPauseMenuItem.setVisible(false); // hide the pause button
    }

    return true;
}

Just a note, this:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
     this.invalidateOptionsMenu();
}

is required to update the action bar. After 3.0 devices, the action bar does not automatically update itself. So, you have to manually tell it to call the "OnPrepareOptionsMenu(Menu)" so that it will refresh the items by calling the "Activity.invalidateOptionsMenu()".

Hope this helps!

Reference: http://developer.android.com/reference/android/app/Activity.html#onPrepareOptionsMenu(android.view.Menu)

http://developer.android.com/reference/android/support/v4/app/ActivityCompat.html#invalidateOptionsMenu(android.app.Activity)

Answer 3

Override the onPrepareOptionsMenu in your activity class and then you can add/ remove or visible/invisible menu items.

Answer 4

private Menu mMenu;

@Override
public boolean onCreateOptionsMenu(Menu menu)
{
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main_activity, menu);

    // Save the menu reference
    mMenu = menu;
    return super.onCreateOptionsMenu(menu);
}

// For example - Call when you need to change icon
private void setActionIcon(boolean showWithBadge)
{
    MenuItem item = mMenu.findItem(R.id.ITEM_ID);

    if(mMenu != null)
    {
        if(showWithBadge)
        {
            item.setIcon(R.drawable.IC_WITH_BADGE);           
        }
        else 
        {
            item.setIcon(R.drawable.IC_WITHOUT_BADGE);
        }
    }
}

Answer 5

Use invalidateOptionsMenu() method.

private boolean isPlaying;

public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.actionbarlogic, menu);
    if (isPlaying) menu.removeItem(R.id.play_button);
    else menu.removeItem(R.id.pause_button);
    return true;
}

public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.play_button:
            // Do what the play button should do here
            isPlaying = true;
            break;

        case R.id.pause_button:
            // Do what the pause button should do here
            isPlaying = false;
            break;
    }
    invalidateOptionsMenu();
    return true;
}

Answer 6

If you want to get the first item from your menu, **

use menu.getItem(0);

this Code woks perfectly :

 @Override
public boolean onCreateOptionsMenu(Menu menu) {

    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.my_menu, menu);
       MenuItem m =  menu.getItem(0);
       m.setIcon(R.drawable.your_icon_here);
    }


    return true;
}