android - toast 不显示

Question

我想在里面的 actionItem() 函数上显示 Toast。但它现在不显示 Toast。

如果我打电话

Context context = getApplicationContext();

在 actionItem() 之前，应用会崩溃。

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;


public class ShowWebViewActivity extends ActionBarActivity {

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

    }


    @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_show_web_view, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        // int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        //        if (id == R.id.action_settings) {
        //            return true;
        //        }

        switch (item.getItemId()) {
            case R.id.action_settings:
                actionItem();
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }

    }
// Context context = getApplicationContext() makes app to crash why??
    public void actionItem(){
// Toast function should call here. But not working
        Context context = getApplicationContext();
        Toast.makeText(context, "Action Setting Selected", Toast.LENGTH_LONG);
    }


}

Answer 1

应该是，

Toast.makeText(context, "Action Setting Selected", Toast.LENGTH_LONG).show();