安卓自定义控件——标题栏的复用

来源：互联网发布：js给input赋值编辑：程序博客网时间：2024/05/19 05:32

一贯作风，先看效果图，再实现

编写自定义属性文件atts.xml，自定义属性中涉及到的属性有左右两边的button的背景图，中间标题的内容，字体大小，字体颜色。

<?xml version="1.0" encoding="utf-8"?><resources>    <declare-styleable name="TopBar">        <attr name="leftBackground" format="reference"/>        <attr name="rightBackground" format="reference"/>        <attr name="titleText" format="string"/>        <attr name="titleTextSize" format="dimension"/>        <attr name="titleTextColor" format="color|reference"/>    </declare-styleable></resources>

编写布局文件layout_topbar.xml，使用相对布局，左边一个button，跟父控件左对齐后外边距为5dp，右边的button也是一样，中间的标题居中显示

<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="wrap_content"    tools:context=".TopBar">    <Button        android:id="@+id/leftButton"        android:layout_width="30dp"        android:layout_height="30dp"        android:layout_alignParentLeft="true"        android:layout_centerVertical="true"        android:layout_marginLeft="5dp" />    <TextView        android:id="@+id/titleTextView"        android:layout_width="wrap_content"        android:layout_height="match_parent"        android:layout_centerHorizontal="true"        android:gravity="center" />    <Button        android:id="@+id/rightButton"        android:layout_width="30dp"        android:layout_height="30dp"        android:layout_alignParentRight="true"        android:layout_centerVertical="true"        android:layout_marginRight="5dp" /></RelativeLayout>

编写自定义控件，继承RelativeLayout，获取自定义属性并给对应的控件赋值

package cn.edu.zafu.view.topbar;import android.content.Context;import android.content.res.TypedArray;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.View;import android.widget.Button;import android.widget.RelativeLayout;import android.widget.TextView;/** * Created by lizhangqu on 2015/1/18. */public class TopBar extends RelativeLayout {    private Button leftButton, rightButton;    private TextView titleTextView;    private OnLeftAndRightClickListener listener;//监听点击事件    //设置监听器    public void setOnLeftAndRightClickListener(OnLeftAndRightClickListener listener) {        this.listener = listener;    }    //设置左边按钮的可见性    public void setLeftButtonVisibility(boolean flag){        if(flag)            leftButton.setVisibility(View.VISIBLE);        else            leftButton.setVisibility(View.GONE);    }    //设置右边按钮的可见性    public void setRightButtonVisibility(boolean flag){        if(flag)            rightButton.setVisibility(View.VISIBLE);        else            rightButton.setVisibility(View.GONE);    }    //按钮点击接口    public interface OnLeftAndRightClickListener {        public void onLeftButtonClick();        public void onRightButtonClick();    }    public TopBar(Context context, AttributeSet attrs) {        super(context, attrs);        LayoutInflater.from(context).inflate(R.layout.layout_topbar, this);        leftButton = (Button) findViewById(R.id.leftButton);        rightButton = (Button) findViewById(R.id.rightButton);        titleTextView = (TextView) findViewById(R.id.titleTextView);        leftButton.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                if (listener != null)                    listener.onLeftButtonClick();//点击回调            }        });        rightButton.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                if (listener != null)                    listener.onRightButtonClick();//点击回调            }        });        //获得自定义属性并赋值        TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.TopBar);        int leftBtnBackground = typedArray.getResourceId(R.styleable.TopBar_leftBackground, 0);        int rightBtnBackground = typedArray.getResourceId(R.styleable.TopBar_rightBackground, 0);        String titleText = typedArray.getString(R.styleable.TopBar_titleText);        float titleTextSize = typedArray.getDimension(R.styleable.TopBar_titleTextSize, 0);        int titleTextColor = typedArray.getColor(R.styleable.TopBar_titleTextColor, 0x38ad5a);        typedArray.recycle();//释放资源        leftButton.setBackgroundResource(leftBtnBackground);        rightButton.setBackgroundResource(rightBtnBackground);        titleTextView.setText(titleText);        titleTextView.setTextSize(titleTextSize);        titleTextView.setTextColor(titleTextColor);    }}

调用自定义控件

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:custom="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".MainActivity">    <cn.edu.zafu.view.topbar.TopBar        android:id="@+id/topbar"        android:layout_width="match_parent"        android:layout_height="50dp"        android:background="#38ad5a"        custom:leftBackground="@drawable/left_button_selector"        custom:rightBackground="@drawable/right_button_selector"        custom:titleText="标题内容"        custom:titleTextColor="#000"        custom:titleTextSize="6sp" /></RelativeLayout>

package cn.edu.zafu.view.topbar;import android.os.Bundle;import android.support.v7.app.ActionBarActivity;import android.widget.Toast;public class MainActivity extends ActionBarActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        TopBar topBar= (TopBar) findViewById(R.id.topbar);        topBar.setOnLeftAndRightClickListener(new TopBar.OnLeftAndRightClickListener() {            @Override            public void onLeftButtonClick() {                Toast.makeText(getApplicationContext(),"left",Toast.LENGTH_SHORT).show();            }            @Override            public void onRightButtonClick() {                Toast.makeText(getApplicationContext(),"right",Toast.LENGTH_SHORT).show();            }        });        topBar.setLeftButtonVisibility(false);    }}

前面布局中用到的两个selector如下
编写left_button_selector.xml

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item android:drawable="@drawable/left_pressed" android:state_pressed="true"/>    <item android:drawable="@drawable/left_normal" /></selector>

编写right_button_selector.xml

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item android:drawable="@drawable/right_pressed" android:state_pressed="true"/>    <item android:drawable="@drawable/right_normal" /></selector>

7 0