Android核心技术-day06-05-Activity生命周期，应用场景

版权声明：心灵泽尘 https://blog.csdn.net/github_38313789/article/details/83757628

package com.gaozewen.lifecycle;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;

public class MainActivity extends AppCompatActivity {

    // 当界面被创建时被调用
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        System.out.println("onCreate");
    }

    // 应用程序界面，用户可见时调用
    @Override
    protected void onStart() {
        super.onStart();
        System.out.println("onStart");
    }

    // 应用程序界面 获得焦点时调用
    // 例：有遮罩层遮住了，重新回来获得焦点时调用
    @Override
    protected void onResume() {
        super.onResume();
        System.out.println("onResume");
    }

    // 当界面再次可见时调用
    @Override
    protected void onRestart() {
        super.onRestart();
        System.out.println("onRestart");
    }

    // 当界面失去焦点时调用
    @Override
    protected void onPause() {
        super.onPause();
        System.out.println("onPause");
    }

    // 当界面不可见时调用
    @Override
    protected void onStop() {
        super.onStop();
        System.out.println("onStop");
    }

    // 当界面被销毁时调用
    @Override
    protected void onDestroy() {
        super.onDestroy();
        System.out.println("onDestroy");
    }

    public void click(View view) {
        Intent intent = new Intent(this, SecondActivity.class);
        startActivity(intent);
    }

}

应用场景

package com.gaozewen.lifecycletest;

import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    private SharedPreferences sp;
    private EditText mEt_content;
    private TextView mTv_blood;
    private int blood = 100;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
//        setContentView(R.layout.activity_main);
//        sp = getSharedPreferences("config", MODE_PRIVATE);
//        mEt_content = (EditText) findViewById(R.id.et_content);
//        mEt_content.setText(sp.getString("content",""));

        setContentView(R.layout.activity_game);
        mTv_blood = (TextView) findViewById(R.id.tv_blood);
    }

    public void click(View view) {
        // manifest.xml android:configChanges="orientation|keyboardHidden|screenSize"
        // 当上述事件发生，血量不会恢复
        blood -= 7;
        if (blood>0) {
            mTv_blood.setText("剩余生命值："+blood);
        } else {
            mTv_blood.setText("已经被 KO 啦！");
        }
    }

    @Override
    protected void onStart() {
        super.onStart();
        System.out.println("继续播放视频...");
    }

    @Override
    protected void onStop() {
        super.onStop();
        System.out.println("暂停播放视频，记录当前播放的位置");
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
//        String content =  mEt_content.getText().toString().trim();
//        SharedPreferences.Editor edit = sp.edit();
//        edit.putString("content",content);
//        edit.apply();
    }
}