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Activity生命周期+四种模式——枯燥重要(五)

2016-07-29 20:31 363 查看
Activity生命周期+四种模式

了解android系统的四大组件

掌握Activity的生命周期

LogCat的使用


Android系统有四个重要的组件,分别是

   Activity

   Service

   BroadcastReceiver

   ContentProvider


Activity是Android程序的呈现层,显示可视化的用户

    界面,并接收与用户交互所产生的界面事件

Android应用程序可以包含一个或多个Activity,一般在

   程序启动后会呈现一个Activity,用于提示用户程序已经

   正常启动


了解Androi系统四个重大组件  Activity  SERvice后台BroadcastReceive广播ContentProvider内容提供者数据共享

Activity生命周期

系统调用方面——事件回调函数

打开onCreate(创建)onStart(开始)onResume(控件绘制完成,跟用户交互)先运行重生:

onRestart onStart onResume(onRestart代替onCreate)退出onPause(暂停)onStop(停止) 

onDestroy(销毁)跳转页面,先是自己onPause(暂停)跳转页面的onCreate/onRestart()然后是自己的onStop(停止)





重点重点重点重要的事说三遍





掌握

 

四种模式。

android:launchMode="singleInstance"

 


单任务模式android:launchMode="singleTask"  首页想退出程序。在它之前都销毁了。

Singletop  加载模式//在栈顶服用不再重建

单实例模式android:launchMode="singleInstance"



1.standard 标准模式也是Activity默认的加载模式。按调用顺序压入Activity栈

2.singleTop 栈顶单一模式,当Actiwity栈顶已存在实例,则不重新创建,佛祖创建。

3.singleTask 单任务模式,[b]当Actiwity栈中存在实例,将销毁栈中此实例之上的实例。[/b]

4.singleInstance单实例模式,实例创建后放在单独的栈中,不与其他实例共享Activity栈



1.MainActivity程序代码


package com.example.jreduch729;

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

public class MainActivity extends AppCompatActivity {
private Button bt1;
private Button bt2,bt3;
private Button btqq;
private TextView tv;
private TextView tv1,tvqq;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.e("====MainActivity=","onCreate");

tv1=(TextView)findViewById(R.id.tv1) ;
Intent intent4=getIntent();
String d=intent4.getStringExtra("daan");
tv1.setText("问题结果是:"+d);

tvqq=(TextView)findViewById(R.id.tvqq) ;
Intent intent2=getIntent();
String use=intent2.getStringExtra("use");
Intent intent3=getIntent();
String usepsw=intent3.getStringExtra("usepsw");
tvqq.setText("QQ账号+密码:"+use+"+"+usepsw);

bt1=(Button)findViewById(R.id.bt1);
bt2=(Button)findViewById(R.id.bt2);
bt3=(Button)findViewById(R.id.bt3);
tv=(TextView)findViewById(R.id.tv) ;
bt1.setOnClickListener(new View.OnClickListener() {
@Override
//跳转
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this,SecondActivity.class);
startActivity(intent);
}
});

bt2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this,SecondActivity.class);

intent.putExtra("arg1",5);
intent.putExtra("arg2",6);
intent.putExtra("arg3","hh");

st<span style="font-size:14px;">artActivityForResult(intent,110);  //一对
}
});
bt3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this,MainTeacherActivity.class);
;
intent.putExtra("arg0","你高中数学体育老师教?");

startActivity(intent);
}
});
btqq=(Button)findViewById(R.id.btqq);
btqq.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this,QqActivity.class);
startActivity(intent);
}
});
}

//返回结果都要走这个程序
@Override                                         //一对
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
Log.e("==requestCode",""+requestCode);
Log.e("==resultCode",""+resultCode);

tv.setText("结果是:"+resultCode+data.getStringExtra("result2")+data.getStringExtra("result1"));
//        if(requestCode==100){
//
//        }else if(requestCode==110){
//            tv.setText("结果是:"+resultCode);
//        }
//
}

@Override
protected void onStart() {    //开始启动
super.onStart();
Log.e("====MainActivity=","onStart");
}
@Override
protected void onRestart() {  //重新启动重新开始
super.onRestart();
Log.e("====MainActivity=","onRestart");
}
@Override
protected void onResume() {   //
super.onResume();
Log.e("====MainActivity=","onResume");
}
@Override
protected void onPause() {   //暂停停止
super.onPause();
Log.e("====MainActivity=","onPause");

}
@Override
protected void onStop() {
super.onStop();
Log.e("====MainActivity=","onStop");
}
@Override
protected void onDestroy() {
super.onDestroy();
Log.e("====MainActivity=","onDestroy");
}
}
</span>
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.jreduch729.MainActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/bt1"
android:text="跳转画面"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/bt2"
android:layout_below="@+id/bt1"
android:text="跳转画面返回结果"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="@+id/tv"
android:layout_below="@+id/bt2"
android:textSize="20dp"
android:text="结果是::"
android:textColor="#f81111"
android:textStyle="normal|bold|italic" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/bt3"
android:layout_below="@+id/tv"
android:text="你高中数学体育老师教?"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="@+id/tv1"
android:layout_below="@+id/bt3"
android:textSize="20dp"
android:text="问题结果"
android:textColor="#f81111"
android:textStyle="normal|bold|italic" />

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/btqq"
android:layout_below="@+id/tv1"
android:text="QQ登陆"
/>
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:id="@+id/tvqq"
android:layout_below="@+id/btqq"
android:textSize="20dp"
android:text="QQ账号+密码"
android:textColor="#f81111"
android:textStyle="normal|bold|italic" />

</RelativeLayout>
</span>

2.MainTeacherActivity程序代码



<span style="font-size:14px;">package com.example.jreduch729;

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

public class MainTeacherActivity extends AppCompatActivity {
public Button bt1;
public TextView tv1;
public TextView et;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_teacher);
tv1=(TextView)findViewById(R.id.tv1) ;
Intent intent5=getIntent();
String d1=intent5.getStringExtra("arg0");
tv1.setText("问题——"+d1);
bt1=(Button)findViewById(R.id.bt1);
final   EditText daan=(EditText)findViewById(R.id.et);
bt1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(MainTeacherActivity.this,MainActivity.class);

intent.putExtra("daan", daan.getText().toString());

startActivity(intent);
}
});

}

}
</span>
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.jreduch729.MainTeacherActivity">

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/tv"
android:text="问题:"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/tv1"
android:layout_below="@id/tv"
android:text="问题:::"
android:textSize="20dp"/>

<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/et"
android:text="请输入问题答案"
android:layout_below="@id/tv1"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/bt1"
android:layout_below="@id/et"
android:text="完成"
android:layout_alignParentEnd="true"
/>
</RelativeLayout>
</span>
3.SecondActivity程序代码

<span style="font-size:18px;">package com.example.jreduch729;</span><span style="font-size:14px;">

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

public class SecondActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
Log.e("====SecondActivity=","onCreate");

Intent intent=getIntent();
int arg1=intent.getIntExtra("arg1",0);
int arg2=intent.getIntExtra("arg2",0);
String arg3=intent.getStringExtra("arg3");
intent.putExtra("result1",arg3);
intent.putExtra("result2","数据返回"+arg3);
if (arg1>0&&arg2>0) {
// setResult(120);
setResult(arg1 + arg2,intent);
finish();
}

}
@Override
protected void onStart() {    //开始启动
super.onStart();
Log.e("====SecondActivity=","onStart");
Log.d("====SecondActivity=","onStart");
Log.w("====SecondActivity=","onStart");
Log.v("====SecondActivity=","onStart");
Log.i("====SecondActivity=","onStart");
}
@Override
protected void onRestart() {  //重新启动重新开始
super.onRestart();
Log.e("====SecondActivity=","onRestart");
}
@Override
protected void onResume() {   // 控件绘制完成
super.onResume();
Log.e("====SecondActivity=","onResume");
}
@Override
protected void onPause() {   //暂停停止
super.onPause();
Log.e("====SecondActivity=","onPause");

}
@Override
protected void onStop() {  //停止
super.onStop();
Log.e("====SecondActivity=","onStop");
}
@Override
protected void onDestroy() {  //破坏毁坏销毁
super.onDestroy();
Log.e("====SecondActivity=","onDestroy");</span><span style="font-size:18px;">
}
}
</span>
4.QqAActivity程序代码

<span style="font-size:14px;">package com.example.jreduch729;

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

public class QqActivity extends AppCompatActivity {
public Button bt1;
public TextView et1;
public TextView et2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_qq);
final EditText use=(EditText)findViewById(R.id.et1);
final   EditText usepsw=(EditText)findViewById(R.id.et2);

bt1=(Button)findViewById(R.id.bt1);
bt1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(QqActivity.this,MainActivity.class);

intent.putExtra("use", use.getText().toString());
intent.putExtra("usepsw", usepsw.getText().toString());
startActivity(intent);
}
});
}
}
</span>










作者:冲天之峰   20160729

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