自定义TopBar

1、分析自定义的TopBar所需要的属性，包括左按钮的字体颜色，字体内容，背景(leftTextColor,leftText,leftBackground)，右按钮的字体颜色，字体内容，背景(rightTextColor,rightText,rigthtBackground)，及标题的字体内容，字体颜色，字体大小(title,titleTextColor,titleTextSize)。在res目录下新建attrs文件，代码如下

<?xml version="1.0" encoding="utf-8"?><resources>    <declare-styleable name="Topbar">        <attr name="title" format="string"/>        <attr name="titleTextSize" format="dimension"/>        <attr name="titleTextColor" format="color"/>        <attr name="leftTextColor" format="color"/>        <attr name="leftBackground" format="reference|color"/>        <attr name="leftText" format="string"/>        <attr name="rightTextColor" format="color"/>        <attr name="rightBackground" format="reference|color"/>        <attr name="rightText" format="string"/>    </declare-styleable></resources>

2、实现一个我们自己的TopBar。可加入左右按钮点击事件，采用接口回调的方式，达到代码复用的目的。

package com.example.activity;import android.content.Context;import android.content.res.TypedArray;import android.graphics.drawable.Drawable;import android.util.AttributeSet;import android.view.Gravity;import android.view.View;import android.widget.Button;import android.widget.RelativeLayout;import android.widget.TextView;public class TopBar extends RelativeLayout {private Button leftButton, rightButton;private TextView tvTitle;private int leftTextColor;private Drawable leftBackground;private String leftText;private int rightTextColor;private Drawable rightBackground;private String rightText;private float titleTextSize;private int titleTextColor;private String title;private LayoutParams leftParams, rightParams, titleParams;private TopbarClickListener listener;public interface TopbarClickListener{public void leftClick();public void rightClick();}public void setOnTopClickListener(TopbarClickListener listener){this.listener = listener;}public TopBar(final Context context, AttributeSet attrs) {super(context, attrs);TypedArray tArray = context.obtainStyledAttributes(attrs,R.styleable.Topbar);leftTextColor = tArray.getColor(R.styleable.Topbar_leftTextColor, 0);leftBackground = tArray.getDrawable(R.styleable.Topbar_leftBackground);leftText = tArray.getString(R.styleable.Topbar_leftText);rightTextColor = tArray.getColor(R.styleable.Topbar_rightTextColor, 0);rightBackground = tArray.getDrawable(R.styleable.Topbar_rightBackground);rightText = tArray.getString(R.styleable.Topbar_rightText);titleTextSize = tArray.getDimension(R.styleable.Topbar_titleTextSize, 0);titleTextColor = tArray.getColor(R.styleable.Topbar_titleTextColor, 0);title = tArray.getString(R.styleable.Topbar_title);tArray.recycle();leftButton = new Button(context);rightButton = new Button(context);tvTitle = new TextView(context);leftButton.setTextColor(leftTextColor);leftButton.setBackground(leftBackground);leftButton.setText(leftText);rightButton.setTextColor(rightTextColor);rightButton.setBackground(rightBackground);rightButton.setText(rightText);tvTitle.setText(title);tvTitle.setTextSize(titleTextSize);tvTitle.setTextColor(titleTextColor);tvTitle.setGravity(Gravity.CENTER);setBackgroundColor(0xcccccccc);leftParams = new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);leftParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT, TRUE);addView(leftButton, leftParams);rightParams = new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);rightParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, TRUE);addView(rightButton, rightParams);titleParams = new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.MATCH_PARENT);titleParams.addRule(RelativeLayout.CENTER_IN_PARENT, TRUE);addView(tvTitle, titleParams);leftButton.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {listener.leftClick();}});rightButton.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {listener.rightClick();}});}}

3、使用我们的topBar。

xml文件

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:custom="http://schemas.android.com/apk/res/com.example.activity"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="${packageName}.${activityClass}" >    <com.example.activity.TopBar        android:id="@+id/topBar"        android:layout_width="match_parent"        android:layout_height="40dp"        custom:leftTextColor="#000000"        custom:leftBackground="#123456"        custom:leftText="Back"        custom:rightBackground="#123456"        custom:rightText="More"        custom:rightTextColor="#000000"        custom:title="标题"        custom:titleTextColor="#123412"         custom:titleTextSize="15sp"/></RelativeLayout

在Activity中引用。

TopBar topBar = (TopBar) findViewById(R.id.topBar);topBar.setOnTopClickListener(new TopbarClickListener() {@Overridepublic void rightClick() {// TODO Auto-generated method stubToast.makeText(TopBarActivity.this, "you clicked the rightBtn", 0).show();}@Overridepublic void leftClick() {// TODO Auto-generated method stubToast.makeText(TopBarActivity.this, "you clicked the leftBtn", 0).show();}});