android fragment使用要点

package cc.ives.main; import cc.ives.fragment.FragmentOne; import cc.ives.fragment.FragmentThree; import cc.ives.fragment.FragmentTwo; import cc.ives.fragment.R; import android.app.Activity; import android.app.FragmentManager; import android.app.FragmentTransaction; import android.os.Bundle; import android.util.DisplayMetrics; import android.view.View; import android.view.View.OnClickListener; import android.widget.TextView; import android.widget.Toast; /** * 测试fragment */ public class Fragment_testActivity extends Activity { private TextView tab1; private TextView tab2; private TextView tab3; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); tab1 = (TextView) findViewById(R.id.tab1); tab2 = (TextView) findViewById(R.id.tab2); tab3 = (TextView) findViewById(R.id.tab3); FragmentManager fm = getFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); FragmentOne f1 = new FragmentOne(Fragment_testActivity.this); ft.replace(R.id.container, f1); ft.commit(); ChangeTabListener ctl = new ChangeTabListener(); tab1.setOnClickListener(ctl); tab2.setOnClickListener(ctl); tab3.setOnClickListener(ctl); // DisplayMetrics metric = new DisplayMetrics(); // getWindowManager().getDefaultDisplay().getMetrics(metric); // int width = metric.widthPixels; // 屏幕宽度（像素） // int height = metric.heightPixels; // 屏幕高度（像素） // float density = metric.density; // 屏幕密度（0.75 / 1.0 / 1.5） // int densityDpi = metric.densityDpi; // 屏幕密度DPI（120 / 160 / 240） // Toast.makeText(this, "宽："+width+"高:"+height+"密度:"+density+"DPI:"+densityDpi, Toast.LENGTH_LONG).show(); } private class ChangeTabListener implements OnClickListener{ @Override public void onClick(View arg0) { FragmentManager fm = getFragmentManager(); FragmentTransaction ft = fm.beginTransaction(); switch(arg0.getId()){ case R.id.tab1: FragmentOne f1 = new FragmentOne(Fragment_testActivity.this); ft.replace(R.id.container, f1); break; case R.id.tab2: FragmentTwo f2 = new FragmentTwo(); ft.replace(R.id.container, f2); break; case R.id.tab3: FragmentThree f3 = new FragmentThree(); ft.replace(R.id.container, f3); break; } ft.commit(); } } }