以下选项卡式活动是由Android Studio 1.2.2向导创建的，它在API 9中运行良好，但someboyd告诉我不推荐使用ActionBarActivity，
所以我希望将public class MainActivity extends ActionBarActivity implements ActionBar.TabListener替换为public class MainActivity extends AppCompatActivity implements ActionBar.TabListener，并保持所有其他代码相同，是否可以？
谢谢！
package com.example.cuiwei.myapplication;
import java.util.Locale;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.app.FragmentPagerAdapter;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity implements ActionBar.TabListener {
/**
* The {@link android.support.v4.view.PagerAdapter} that will provide
* fragments for each of the sections. We use a
* {@link FragmentPagerAdapter} derivative, which will keep every
* loaded fragment in memory. If this becomes too memory intensive, it
* may be best to switch to a
* {@link android.support.v4.app.FragmentStatePagerAdapter}.
*/
SectionsPagerAdapter mSectionsPagerAdapter;
/**
* The {@link ViewPager} that will host the section contents.
*/
ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Set up the action bar.
final ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Create the adapter that will return a fragment for each of the three
// primary sections of the activity.
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
// When swiping between different sections, select the corresponding
// tab. We can also use ActionBar.Tab#select() to do this if we have
// a reference to the Tab.
mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
// For each of the sections in the app, add a tab to the action bar.
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
// Create a tab with text corresponding to the page title defined by
// the adapter. Also specify this Activity object, which implements
// the TabListener interface, as the callback (listener) for when
// this tab is selected.
actionBar.addTab(
actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(i))
.setTabListener(this));
}
}
@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, 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;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
// When the given tab is selected, switch to the corresponding page in
// the ViewPager.
mViewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}
@Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}
/**
* A {@link FragmentPagerAdapter} that returns a fragment corresponding to
* one of the sections/tabs/pages.
*/
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
return PlaceholderFragment.newInstance(position + 1);
}
@Override
public int getCount() {
// Show 3 total pages.
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
Locale l = Locale.getDefault();
switch (position) {
case 0:
return getString(R.string.title_section1).toUpperCase(l);
case 1:
return getString(R.string.title_section2).toUpperCase(l);
case 2:
return getString(R.string.title_section3).toUpperCase(l);
}
return null;
}
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}
答案 0 :(得分：1)
您可以使用enum安全地替换from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.uix.floatlayout import FloatLayout
from kivy.clock import Clock
energy = 100
hours = 4
class app1(App):
def build(self):
self.f = FloatLayout()
#Labels
self.energy_label = Label(text = "Energy = " + str(energy), size_hint=(.1, .15),pos_hint={'x':.05, 'y':.9})
self.time_label = Label(text = "Hours = " + str(hours), size_hint=(.1, .15),pos_hint={'x':.9, 'y':.9})
self.name_label = Label(text = "Game", size_hint=(.1, .15),pos_hint={'x':.45, 'y':.9})
self.main_label = Label(text = "Default_text", size_hint=(1, .55),pos_hint={'x':0, 'y':.35})
#Main Buttons
self.inventory_button = Button(text = "Inventory", size_hint=(.3, .1),pos_hint={'x':.65, 'y':.2})
self.help_button = Button(text = "Help", size_hint=(.3, .1),pos_hint={'x':.65, 'y':.1})
self.craft_button = Button(text = "Craft", size_hint=(.3, .1),pos_hint={'x':.05, 'y':.1})
self.food_button = Button(text = "Food", size_hint=(.3, .1),pos_hint={'x':.35, 'y':.2})
self.go_button = Button(text = "Go", size_hint=(.3, .1),pos_hint={'x':.35, 'y':.1})
self.walk_button = Button(text = "Walk", size_hint=(.3, .1),pos_hint={'x':.05, 'y':.2})
def update(self, *args):
self.main_widget.text = str(self.current_text)
self.f.add_widget(self.energy_label)
self.f.add_widget(self.main_label)
self.f.add_widget(self.time_label)
self.f.add_widget(self.inventory_button)
self.f.add_widget(self.help_button)
self.f.add_widget(self.craft_button)
self.f.add_widget(self.food_button)
self.f.add_widget(self.go_button)
self.f.add_widget(self.walk_button)
self.f.add_widget(self.name_label)
self.current_text = "Default"
Clock.schedule_interval(update, 1)
return self.f
def update_label(input):
input = self.current_text
help_button.bind(on_press = update_label("success!"))
if __name__=="__main__":
app1().run()
。
正如您在版本v22.1.0 ActionBarActivity v7-appcompat source code中看到的那样，只需扩展AppCompatActivity：
ActionBarActivity