【移动应用开发技术】BaseActivity公用界面的使用

【移动应用开发技术】BaseActivity公用界面的使用

在开发Android应用中，有时候会在多个界面中出现同样的布局如在顶部或底部显示菜单栏，时间显示等。为了避免麻烦，不用在每个界面都布局，这个时候我们用到了BaseActivity（不是系统的自己定义的）在BaseActivity布局里，我们可以把公用的布局先写出来，如界面顶部有返回按钮，有当前界面Title。在界面底部有时间显示栏，且时间和系统时间同步，不断刷新。在BaseActivity的布局里，我们留出LinearLayout这样一个线性布局，并且设置属性id，这样其他界面的layout放置到这个LinearLayout里就可以了。我们看一下具体的使用步骤：1、定义一个公用类的Activity我这里叫MyBaseActivity继承Activity并且该MyBaseActivity为抽象类abstract，因为里面有抽象方法2、定义一个基本类如FirstActivity继承MyBaseActivity并实现MyBaseActivity里面的抽象方法3、在MyBaseActivity类中有两个抽象方法onBaseCreare(Bundlebundle)和initView()其中onBaseCreare()方法顾名思义是实现界面显示的也就是类似于onCreate()中的setContentView(layout),initView()方法用于初始化一些数据，如Title的设置，时间显示等。4、在MyBaseActivity类中有getbtn_left()方法，可获取公共控件的控制。贴出详细代码：先看xml布局：//activity_my_base.xml<LinearLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

android:layout_width="match_parent"

android:layout_height="fill_parent"

android:orientation="vertical"

android:weightSum="10"

>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="0dp"

android:layout_weight="1"

android:weightSum="3"

>

<Button

android:id="@+id/button1_base"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:text="左按钮"

/>

<TextView

android:id="@+id/title"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center"

android:text="标题"

/>

<Button

android:id="@+id/button3_base"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:text="右按钮"

/>

</LinearLayout>

<LinearLayout

android:id="@+id/layout_id"

android:layout_width="fill_parent"

android:layout_height="0dp"

android:layout_weight="8.5"

android:orientation="horizontal"

>

</LinearLayout>

<LinearLayout

android:id="@+id/layout_bottom"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_weight="0.5"

>

<TextView

android:id="@+id/time"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_gravity="bottom"

android:gravity="center"

android:text="标题"

/>

</LinearLayout>

</LinearLayout>//activity_first.xml<LinearLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical"

android:weightSum="1"

tools:context=".FirstActivity"

>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:orientation="horizontal"

>

</LinearLayout>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="0dp"

android:layout_gravity="center"

android:layout_weight="1"

android:orientation="vertical"

>

<Button

android:id="@+id/button1"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:text="into

SecondActivity"

/>

<Button

android:id="@+id/button2"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:layout_marginTop="20dp"

android:text="Button2"

/>

</LinearLayout>

</LinearLayout>//activity_second.xml<LinearLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical"

android:weightSum="3"

>

<Button

android:id="@+id/button1_second"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_weight="1"

android:text="返

回"

/>

<Button

android:id="@+id/button12_second"

android:layout_width="fill_parent"

android:layout_height="50dp"

android:layout_weight="1"

android:text="Button"

/>

<Button

android:id="@+id/button3_second"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_weight="1"

android:text="Button"

/>

</LinearLayout>

</LinearLayout>//接下来看一下类中的源码首先是公共类MyBaseActivity

package

com.example.testbaseactivity;

import

java.text.SimpleDateFormat;

import

java.util.Date;

import

java.util.TimerTask;

import

android.annotation.SuppressLint;

import

android.app.Activity;

import

android.os.Bundle;

import

android.os.Handler;

import

android.view.View;

import

android.view.View.OnClickListener;

import

android.widget.Button;

import

android.widget.LinearLayout;

import

android.widget.Toast;

import

android.widget.LinearLayout.LayoutParams;

import

android.widget.TextView;

public

abstract

class

MyBaseActivity

extends

Activity

implements

OnClickListener{

//

内容区域的布局

private

View

contentView;

private

LinearLayout

layoutBody;

private

Button

btn1;

private

Button

btn2;

private

TextView

tv;

private

TextView

vTime;

private

String

timeString;

@Override

protected

void

onCreate(Bundle

savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_my_base);

btn1

=

(Button)

findViewById(R.id.button1_base);

btn2

=

(Button)

findViewById(R.id.button3_base);

btn1.setOnClickListener(this);

btn2.setOnClickListener(this);

tv

=

(TextView)

findViewById(R.id.title);

layoutBody

=

(LinearLayout)

findViewById(R.id.layout_id);

vTime

=

(TextView)

findViewById(R.id.time);

onBaseCreare(savedInstanceState);

initView();

}

/**

*

初始化界面

*

@param

bundle

*/

public

abstract

void

onBaseCreare(Bundle

bundle);

/**

*

初始化数据

*/

public

abstract

void

initView();

/**

*

底部栏刷新时间

*

刷新间隔1s

*/

public

void

setTime()

{

int

delay

=

0;

int

period

=

1000;//

循环间隔

1000ms

java.util.Timer

timer

=

new

java.util.Timer();

timer.scheduleAtFixedRate(new

TimerTask()

{

public

void

run()

{

timeString

=

getTime();

myhandler.sendEmptyMessage(0x0001);

}

},

delay,

period);

}

@SuppressLint("HandlerLeak")

private

Handler

myhandler

=

new

Handler()

{

public

void

dispatchMessage(android.os.Message

msg)

{

switch

(msg.what)

{

case

0x0001:

vTime.setText(timeString);

break;

}

}

};

@SuppressLint("SimpleDateFormat")

public

static

String

getTime()

{

Date

nowdate

=

new

Date();

//

当前时间

SimpleDateFormat

dateFormat

=

new

SimpleDateFormat("yyyy-MM-dd

HH:mm:ss");

return

dateFormat.format(nowdate);

}

/**

*

设置标题

*

*

@param

title

*/

public

void

setTitle(String

title)

{

if

(null

!=

tv)

{

tv.setText(title);

}

}

/**

*

隐藏上方的标题栏

*/

public

void

hideTitleView()

{

if

(null

!=

btn1)

{

btn1.setVisibility(View.INVISIBLE);

}

}

public

void

setContentViewId(int

layoutId)

{

contentView

=

getLayoutInflater().inflate(layoutId,

null);

if

(layoutBody.getChildCount()

>

0)

{

layoutBody.removeAllViews();

}

if

(contentView

!=

null)

{

LayoutParams

params

=

new

LayoutParams(LayoutParams.MATCH_PARENT,

LayoutParams.MATCH_PARENT);

layoutBody.addView(contentView,

params);

}

}

/**

*

得到左边的按钮

*

*

@return

*/

public

Button

getbtn_left()

{

return

btn1;

}

/**

*

得到右边的按钮

*

*

@return

*/

public

Button

getbtn_right()

{

return

btn2;

}

@Override

public

void

onClick(View

arg0)

{

//

TODO

Auto-generated

method

stub

if(arg0.equals(btn1)){

Toast.makeText(MyBaseActivity.this,

"MyBaseActivitybtn1",

Toast.LENGTH_SHORT).show();

}

if(arg0.equals(btn2)){

Toast.makeText(MyBaseActivity.this,

"MyBaseActivitybtn2",

Toast.LENGTH_SHORT).show();

}

}

}//第一个界面FirstActivity

package

com.example.testbaseactivity;

import

android.content.Intent;

import

android.os.Bundle;

import

android.view.View;

import

android.widget.Button;

import

android.widget.Toast;

public

class

FirstActivity

extends

MyBaseActivity

{

private

Button

btn1;

private

Button

btn2;

private

Button

btn_left;

private

Button

btn_right;

@Override

public

void

onBaseCreare(Bundle

bundle)

{

setContentViewId(R.layout.activity_first);

btn_left

=

getbtn_left();

btn_right

=

getbtn_right();

findViewById();

}

@Override

public

void

initView()

{

setTitle("FirstActivity");

setTime();

}

public

void

findViewById(){

btn1

=

(Button)

findViewById(R.id.button1);

btn2

=

(Button)

findViewById(R.id.button2);

btn1.setOnClickListener(this);

btn2.setOnClickListener(this);

}

@Override

public

void

onClick(View

arg0)

{

if(arg0.equals(btn1)){

Intent

intent

=

new

Intent(this,

SecondActivity.class);

startActivity(intent);

}

if(arg0.equals(btn2)){

Toast.makeText(FirstActivity.this,

"FirstActivitybtn2",

Toast.LENGTH_SHORT).show();

}

if(arg0.equals(btn_left)){

Toast.makeText(FirstActivity.this,

"FirstActivitybtn_left",

Toast.LENGTH_SHORT).show();

}

if(arg0.equals(btn_right)){

Toast.makeText(FirstActivity.this,

"FirstActivitybtn_right",

Toast.LENGTH_SHORT).show();

}

}

}//第二个界面package

com.example.testbaseactivity;

import

android.os.Bundle;

import

android.view.View;

import

android.view.View.OnClickListener;

import

android.widget.Button;

import

android.widget.Toast;

public

class

SecondActivity

extends

MyBaseActivity

implements

OnClickListener{

private

Button

btn;

@Override

public

void

onBaseCreare(Bundle

bundle)

{

setContentViewId(R.layout.activity_second);

btn

=

(Button)

findViewById(R.id.button1_second);

btn.setOnClickListener(this);

}

@Override

public

void

initView()

{

setTime();

setTitle("SecondActivity");

}

@Override

public

void

onClick(View

arg0)

{

//

TODO

Auto-generated

method

stub

if(arg0.eq