我正在关注有关android中的标签的教程,并且所做的一切都与视频中的完全一样。有很多代码,但是我在其中一行tab1.setTabListener(new ActionBar.TabListener(fragment1))上遇到错误。它说“ TabListener”是抽象的;无法实例化。我该如何解决?
这是活动的完整代码,其中包含错误:
import android.app.ActionBar;
import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
public class ProjectCreateScreen extends ActionBarActivity {
@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.secondary_layout1);
Toolbar toolbar = (Toolbar) findViewById(R.id.AwesomeBar);
setSupportActionBar(toolbar);
ActionBar.Tab tab1, tab2, tab3;
// Fragments that will load when the tabs are clicked
Fragment fragment1 = new TabFragment1();
Fragment fragment2 = new TabFragment2();
Fragment fragment3 = new TabFragment3();
ActionBar actionBar = getActionBar();
// Set the current navigation mode to tabs
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Add titles to tabs
tab1 = actionBar.newTab().setText("Tab1");
tab2 = actionBar.newTab().setText("Tab2");
tab3 = actionBar.newTab().setText("Tab3");
// Set tab listeners which provide callbacks for tab events
// A callback informs another class when an action occurs
tab1.setTabListener(new ActionBar.TabListener(fragment1));
tab2.setTabListener(new ActionBar.TabListener(fragment2));
tab3.setTabListener(new ActionBar.TabListener(fragment3));
// Adds tabs to the actionbar
actionBar.addTab(tab1);
actionBar.addTab(tab2);
actionBar.addTab(tab3);
}
}
最佳答案
您必须创建一个实现TabListener接口的类
protected class MyTabsListener implements ActionBar.TabListener{
private Fragment fragment;
public MyTabsListener(Fragment fragment){
this.fragment = fragment;
}
public void onTabSelected(Tab tab, FragmentTransaction ft){
ft.add(R.id.layout2, fragment, null);
}
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
ft.remove(fragment);
}
}
然后设置tabListener
tab1.setTabListener(new MyTabsListener(fragment1));