Android开发 ---Activity的7种运行状态
创建 --> 启动 --> 运行 --> 暂停 --> 停止 --> 销毁
重启
操作图解：
1、MainActivity.java
package com.example.android_activity;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
public class MainActivity extends Activity {
//创建Activity时调用，一个生命周期只有一次执行
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//绑定当前窗体的布局文件
setContentView(R.layout.activity_main);
Toast.makeText(this,"Activity创建时调用onCreate()方法",Toast.LENGTH_LONG).show();
}
//去到注册窗体
public void toRegister(View view){
Intent intent=new Intent(this,RegisterActivity.class);
startActivity(intent);
}
//Activity启动时调用
@Override
protected void onStart() {
super.onStart();
Toast.makeText(this,"Activity被启动时调用onStart()方法",Toast.LENGTH_LONG).show();
}
//Activity进入运行状态时调用[进入激活必经之路]
@Override
protected void onResume() {
super.onResume();
Toast.makeText(this,"Activity进入运行状态时调用onResume方法",Toast.LENGTH_LONG).show();
}
//Activity从Stop状态重启时调用
@Override
protected void onRestart() {
super.onRestart();
Toast.makeText(this,"Activity从停止状态重启时调用onRestart()方法",Toast.LENGTH_LONG).show();
}
//Activity进入暂停状态[退出激活必经之路]
@Override
protected void onPause() {
super.onPause();
Toast.makeText(this,"Activity进入暂停状态时调用onPause()方法",Toast.LENGTH_LONG).show();
}
//进入停止状态时调用
@Override
protected void onStop() {
super.onStop();
Toast.makeText(this,"Activity进入停止状态时调用onStop()方法",Toast.LENGTH_LONG).show();
}
//销毁Activity实例,一个生命周期只有一次执行
@Override
protected void onDestroy() {
super.onDestroy();
Toast.makeText(this,"Activity被销毁时调用onDestroy()方法",Toast.LENGTH_LONG).show();
}
}
2、RegisterActivity.java
package com.example.android_activity;
import android.app.Activity;
import android.os.Bundle;
public class RegisterActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
}
}
3、activity_main.xml
xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > android:layout_width="match_parent" android:layout_height="wrap_content" android:textSize="30sp" android:onClick="toRegister" android:text="用户注册" />
效果图：