如何从另一个类设置Android工具栏的标题？

Question

I would like to do something like this:

if (total != 0) {
    percentage = String.valueOf((count * 100) / total);
    Log.e("Percentage", percentage);
    myActivity.getSupportActionBar().setTitle("Progress: " + percentage + "%.");
}

However, I can't call getSupportActionBar() because it says Non-static method 'getSupportActionBar()' cannot be referenced from a static context . How can I solve this?

Update

This is the method inside my public class where I'd like to call the above code;

     @Override
public void onBindViewHolder(final ViewHolder holder, int position) {
    holder.checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
         @Override
         public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

         }
         });
         }

Answer 1

Casting your activity can resolve your problem. Suppose your Activity Name is YourCustomActivity. Now cast the Activity like below. Hope it will work.

    YourCustomActivity activity=(YourCustomActivity)myActivity;
    activity.getSupportActionBar().setTitle("");

Please Let me know if it works or not.

Answer 2

You can pass activity parameter to another class and use activities funcitons like below;

public class CityModel {

    Activity activity;

    public CityModel(Activity activity) {
        this.activity = activity;
    }

    private void doIt() {
        ((YourActivity) activity).changeTitle("New Title");
    }

}

And define this class instance like below;

 public class YourActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        CityModel model = new CityModel(this); // this-> Your activity.
     }

     public void changeTitle(String newTitle){
       getSupportActionBar().setTitle(newTitle);
     }
}

Hope it helps.

Answer 3

Thanks to other answers, but none of them fit what I wanted.

I solved it by moving the code to the activity in question and setting the title from there. However, the main change was to post the percentage value from a listener method, in my case: onItemCheckBoxChecked . This meant that every time a user checked a box (could be other listeners in case of a textview or something else) the percentage was calculated in real time. I also made the percentage variable public.

Answer 4

Because getSupportActionBar() is not static method. If you are using this method in static class or static method then you will get below error.

Non-static method getSupportActionBar() cannot be referenced from a static context

If you want to common method for it you can make one think create public method in your activity and call in your fragments .

public void setToolBar(String title) {
        getSupportActionBar().setTitle(title);
}

If you have Activity, simply you can call below code.

getSupportActionBar().setTitle(title);

Edit My Code :

public static void setToolbar(final AppCompatActivity activity,String title){
    activity.getSupportActionBar().setTitle(title);
}

Edit Code : My RecyclerViewAdapter class :

public class ExploreGalleryAdapter extends RecyclerView.Adapter<ExploreGalleryAdapter.ViewHolder> {

    private AppCompatActivity activity;
    private ArrayList<ExploreGalleryModel> exploreGalleryModelArrayList;
    //    private String status;


    public ExploreGalleryAdapter(AppCompatActivity activity, final ArrayList<ExploreGalleryModel> exploreGalleryModelArrayList, final String status) {
        this.activity = activity;
        this.exploreGalleryModelArrayList = exploreGalleryModelArrayList;
//        this.status = status;
    }

  public void onBindViewHolder(final ViewHolder holder, int position) {
holder.checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                @Override
                public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

activity.getSupportActionBar().setTitle(title);

     }
            });

}