Android 开发笔记___Activity的生命周期

一个activity就是一个页面，入口函数是oncreate()。

• onCreate：创建页面，把页面上各个元素加载到内存
• onStart：开始页面，把页面显示在屏幕
• onResume：恢复页面，让页面活动起来
• onPause：暂停页面
• onStop：停止页面
• onDestroy：销毁页面
• onRestart：重启页面

package com.example.alimjan.hello_world;

import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.TextView;

import com.example.alimjan.hello_world.Utils.DateUtil;

/**
 * Created by alimjan on 7/3/2017.
 */

public class class_3_5_1 extends AppCompatActivity {

    private final static String TAG = "ActHomeActivity";
    private TextView tv_life;
    private String mStr = "";
    private int mState = 0;

    private void refreshLife(String desc) {
        Log.d(TAG, desc);
        mStr = String.format("%s%s %s %s
", mStr, DateUtil.getCurDateStr(), TAG, desc);
        tv_life.setText(mStr);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.code_3_5_1);
        tv_life = (TextView) findViewById(R.id.tv_life);
        refreshLife("onCreate");
    }

    @Override
    protected void onStart() {
        refreshLife("onStart");
        super.onStart();
    }

    @Override
    protected void onStop() {
        refreshLife("onStop");
        super.onStop();
    }

    @Override
    protected void onResume() {
        refreshLife("onResume");
        super.onResume();
    }

    @Override
    protected void onPause() {
        refreshLife("onPause");
        super.onPause();
    }

    @Override
    protected void onRestart() {
        refreshLife("onRestart");
        super.onRestart();
    }

    @Override
    protected void onDestroy() {
        refreshLife("onDestroy");
        super.onDestroy();
    }
    public static void startHome(Context mContext) {
        Intent intent = new Intent(mContext, class_3_5_1.class);
        mContext.startActivity(intent);
    }

}