Android_LaunchMode

1.Activity的启动模式   Fragment
 <1>Standard（默认-标准模式）
  自己可以启动自己（会创新一个新的Activity）
 <2>SingleTop（顶单例模式）
  在栈顶只允许有一个相同的Activity
  自己不能启动自己
 <3>SingleTask（内单例模式）
  如果要启动的Activity存在，则干掉要启动的Activity上面的所有的Activity
 <4>SingleInstance（全局单例模式）

案列代码如下:

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout      xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:app="http://schemas.android.com/apk/res-auto"      xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"      android:layout_height="match_parent"      android:orientation="vertical"      tools:context="com.example.cookie.android0617closeapplication.MainActivity">      <TextView          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:id="@+id/tv_main_text"          android:text="这是主界面" />        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:onClick="jumpSelf"          android:text="跳自己"/>        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"<pre class="html" name="code" snippet_file_name="blog_20170617_1_2664347" code_snippet_id="2450762"><?xml version="1.0" encoding="utf-8"?>  <LinearLayout      xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:app="http://schemas.android.com/apk/res-auto"      xmlns:tools="http://schemas.android.com/tools"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:orientation="vertical"      tools:context="com.example.cookie.android0617closeapplication.BActivity">        <TextView          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:text="这是B界面累"          android:textSize="35sp"          android:background="#6600"          />      <TextView          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:id="@+id/tb_b_word"/>        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:onClick="jumpMain"          android:text="跳到主页面"/>        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:onClick="exit"          android:text="退出应用程序"/>    </LinearLayout>  </pre><br>  android:layout_margin="10dp" android:onClick="jumpOther" android:text="跳别人"/> <Button android:layout_width="match_parent" android:layout_height="wrap_content" android:text="退出应用程序" android:onClick="exit"/></LinearLayout><p></p>  <pre></pre>  <p></p>  <p><span style="font-size:14px"><strong><br>  </strong></span></p>  <p><span style="font-size:14px"><strong><br>  </strong></span></p>  <p><span style="font-size:14px"><strong><br>  </strong></span></p>  <p><span style="font-size:14px"><strong>activity_b.xml代码</strong></span></p>  <p><span style="font-size:14px"></span></p><pre class="html" name="code" snippet_file_name="blog_20170617_2_7364429" code_snippet_id="2450762"><?xml version="1.0" encoding="utf-8"?>  <LinearLayout      xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:app="http://schemas.android.com/apk/res-auto"      xmlns:tools="http://schemas.android.com/tools"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:orientation="vertical"      tools:context="com.example.cookie.android0617closeapplication.BActivity">        <TextView          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:text="这是B界面累"          android:textSize="35sp"          android:background="#6600"          />      <TextView          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:id="@+id/tb_b_word"/>        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:onClick="jumpMain"          android:text="跳到主页面"/>        <Button          android:layout_width="match_parent"          android:layout_height="wrap_content"          android:onClick="exit"          android:text="退出应用程序"/>    </LinearLayout>  </pre><br>  <strong><br>  </strong><p></p>  <p><span style="font-size:14px"><strong><br>  </strong></span></p>  <p><span style="font-size:14px"><strong>主界面的MainActivity.<a title="Java 知识库" class="replace_word" style="color:#df3434; font-weight:bold;" href="http://lib.csdn.net/base/java" target="_blank">Java</a>代码：</strong></span></p>  <p><span style="font-size:14px"></span></p><pre class="html" name="code" snippet_file_name="blog_20170617_3_254368" code_snippet_id="2450762">public class MainActivity extends Activity {        private TextView tv_main_text;      private MyApplication myApplication;      private long firstTime=0;        @Override      protected void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.activity_main);          tv_main_text = (TextView) findViewById(R.id.tv_main_text);          tv_main_text.setText("当前Activity实例："+this+"\n当前任务栈"+this.getTaskId());          //1.获取Myapplication          myApplication = (MyApplication) getApplication();          myApplication.add(this);            }        public void jumpSelf(View view){          Intent intent=new Intent(this,MainActivity.class);          startActivity(intent);      }        public void jumpOther(View view){          Intent intent=new Intent(this,BActivity.class);          //startActivity(intent);          startActivityForResult(intent,0x22);      }        public void exit(View view){          finish();//退出当前的Activity          //finish()和System.exit(0)都是退出当前的Activity,          //但是finish()会调用onDestroy（）方法，         // System.exit(0);          myApplication.exit();      }    //    @Override  //    protected void onActivityResult(int requestCode, int resultCode, Intent data) {  //        super.onActivityResult(requestCode, resultCode, data);  //        exit(null);  //    }        @Override      protected void onDestroy() {          super.onDestroy();          Log.i("test","onDestroy");      }            }  </pre><p></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><strong><span style="font-size:14px"><br>  </span></strong></p>  <p><strong><span style="font-size:14px"><br>  </span></strong></p>  <p><strong><span style="font-size:14px">BActivity.java代码：</span></strong></p>  <p><span style="font-size:14px"></span></p><pre class="html" name="code" snippet_file_name="blog_20170617_4_3144307" code_snippet_id="2450762">public class BActivity extends AppCompatActivity {        private TextView tb_b_word;      private MyApplication myApplication;        @Override      protected void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.activity_b);          tb_b_word = (TextView) findViewById(R.id.tb_b_word);          tb_b_word.setText("当前Activity地址:"+this+"\nTaskId："+this.getTaskId());          //1.获取Myapplication          myApplication = (MyApplication) getApplication();          myApplication.add(this);      }        public void jumpMain(View view){          Intent intent=new Intent(this,MainActivity.class);          startActivity(intent);        }        public void exit(View view){        // finish();         // System.exit(0);          myApplication.exit();      }        @Override      protected void onDestroy() {          super.onDestroy();          Log.i("test","onDestroy");      }      }  </pre><br>  <p></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><span style="font-size:14px"><img alt="" src="http://img.blog.csdn.net/20170617200830674?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvWURDb29raWU=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center"><br>  </span></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><span style="font-size:14px"><br>  </span></p>  <p><span style="font-size:14px"><br>  </span></p>