android

<include>标签解决布局重用问题

如果你已经知道include是什么,只是想知道怎么用,使用示例如下:

①布局文件引入layout 

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<include  
    android:id="@+id/topbar"  
    android:layout_width="match_parent"  
    android:layout_height="wrap_content"  
    layout="@layout/view_topbar" />

②Java代码中访问,获取layout中组件,设置属性:

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private View topbar;  
private TextView txtTitle;  
  
topbar = findViewById(R.id.topbar);  
txtTitle = (TextView) topbar.findViewById(R.id.txtTitle);  
txtTitle.setText("第二页");

就这么简单,你可以关页面了,觉得帮助了你,可以点个赞!

如果不知道,想了解相关以及应用场景请继续看:
本节流程图:

效果图:

代码思路:

核心是顶部的一个titlebar,这里是我们自己写的一个bar,因为后面两个Activity都需要用到,

所以我们直接通过include包含这个bar,然后Java代码中获得该bar实例,再调用bar.findViewById

找到标题栏的TextView修改对应的页面!

详细代码如下:

顶部的bar: view_topbar.xml

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<?xml version="1.0" encoding="utf-8"?>  
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    android:background="#000000" >  
  
    <ImageView  
        android:id="@+id/imgBack"  
        android:layout_width="40dp"  
        android:layout_height="40dp"  
        android:background="@drawable/back" />  
  
    <TextView  
        android:id="@+id/txtTitle"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_centerHorizontal="true"  
        android:layout_marginTop="8dp"  
        android:textColor="#FFFFFF"  
        android:textSize="20sp" />  
  
</RelativeLayout>

接着依次编写三个Activity的布局,二三个activity通过include导入topbar

activity_main.xml:

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<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:background="#D1E5E6"  
    tools:context="com.jay.example.includedemo.MainActivity" >  
  
    <Button  
        android:id="@+id/btnTo"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_centerInParent="true"  
        android:text="跳轉到第二個頁面" />  
  
</RelativeLayout>

activity_second.xml:

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<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:background="#D5E094" >  
  
    <include  
        android:id="@+id/topbar"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        layout="@layout/view_topbar" />  
  
    <Button  
        android:id="@+id/btnTo"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_centerInParent="true"  
        android:text="跳轉到第三個頁面"  
        android:textSize="14sp" />  
  
</RelativeLayout>

activity_third.xml:

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<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:background="#F2CC9F" >  
  
    <include  
        android:id="@+id/topbar"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        layout="@layout/view_topbar" />  
  
    <TextView  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_centerInParent="true"  
        android:text="第三個頁面" />  
  
</RelativeLayout>

编写对应的activity:

MainActivity.java:

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package com.jay.example.includedemo;  
  
import android.app.Activity;  
import android.content.Intent;  
import android.os.Bundle;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.widget.Button;  
  
public class MainActivity extends Activity {  
    private Button btnTo;  
  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
        getViews();  
        setViews();  
    }  
  
    private void getViews() {  
        btnTo = (Button) findViewById(R.id.btnTo);  
    }  
  
    private void setViews() {  
        MyClick myClick = new MyClick();  
        btnTo.setOnClickListener(myClick);  
  
    }  
  
    // 定义事件处理类  
    private class MyClick implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            switch (v.getId()) {  
            case R.id.btnTo:  
                Intent it = new Intent(MainActivity.this, SecondActivity.class);  
                startActivity(it);  
                break;  
            }  
  
        }  
    }  
}

SecondActivity.java:

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package com.jay.example.includedemo;  
  
import android.app.Activity;  
import android.content.Intent;  
import android.os.Bundle;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.widget.Button;  
import android.widget.ImageView;  
import android.widget.TextView;  
  
public class SecondActivity extends Activity {  
    private View topbar;  
    private ImageView imgBack;  
    private TextView txtTitle;  
    private Button btnTo;  
  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_second);  
        getActionBar().hide();  
        getViews();  
        setViews();  
    }  
  
    private void getViews() {  
        topbar = findViewById(R.id.topbar);  
        btnTo = (Button) findViewById(R.id.btnTo);  
        imgBack = (ImageView) topbar.findViewById(R.id.imgBack);  
        txtTitle = (TextView) topbar.findViewById(R.id.txtTitle);  
    }  
  
    private void setViews() {  
        MyClick myClick = new MyClick();  
        txtTitle.setText("第二页");  
        btnTo.setOnClickListener(myClick);  
        imgBack.setOnClickListener(myClick);  
    }  
  
    // 定义事件处理类  
    private class MyClick implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            switch (v.getId()) {  
            case R.id.btnTo:  
                Intent it = new Intent(SecondActivity.this, ThirdActivity.class);  
                startActivity(it);  
                break;  
            case R.id.imgBack:  
                finish();  
                break;  
            }  
  
        }  
    }  
}

ThirdActivity.java:

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package com.jay.example.includedemo;  
  
import android.app.Activity;  
import android.os.Bundle;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.widget.ImageView;  
import android.widget.TextView;  
  
public class ThirdActivity extends Activity {  
    private View topbar;  
    private ImageView imgBack;  
    private TextView txtTitle;  
  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_third);  
        getActionBar().hide();  
        getViews();  
        setViews();  
    }  
  
    private void getViews() {  
        topbar = findViewById(R.id.topbar);  
        imgBack = (ImageView) topbar.findViewById(R.id.imgBack);  
        txtTitle = (TextView) topbar.findViewById(R.id.txtTitle);  
    }  
  
    private void setViews() {  
        MyClick myClick = new MyClick();  
        txtTitle.setText("第三页");  
        imgBack.setOnClickListener(myClick);  
    }  
  
    // 定义事件处理类  
    private class MyClick implements OnClickListener {  
        @Override  
        public void onClick(View v) {  
            switch (v.getId()) {  
            case R.id.imgBack:  
                finish();  
                break;  
            }  
  
        }  
    }  
}

最后再配置文件注册下二三两个Activity即可!

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<activity android:name=".SecondActivity"></activity>  
<activity android:name=".ThirdActivity"></activity>

代码下载:

http://pan.baidu.com/s/1bnpjJhP