记得刚做机顶盒开发的时候</span>，真的把我坑惨了，网上又找都不什么资料，所以只能自己慢慢摸索了。在其中也是学到了一些知识，当然也遇到过许多的问题，so。。。就希望把这些经验分享给其他刚开始步入机顶盒开发的程序猿。。。。。</span>
做机顶盒这块了，最麻烦的就是这个焦点问题了，因为机顶盒都是用遥控操作的，所以在界面上都需要有一个用户操作的焦点！！！下面就带大家写一个在机顶盒中经常用到的界面切换的程序。。。
程序有四个界面，按遥控的左右键，能切换到不同界面，下面是布局。（注：布局最好是新建一个layout-land文件夹存放）
activity_main：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/launch_bg"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<RadioGroup
android:id="@+id/title_group"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="60dip"
android:orientation="horizontal"
android:paddingLeft="120dip"
android:paddingRight="60dip" >
<RadioButton
android:id="@+id/l1"
style="@style/TitleButton"
android:layout_width="180dip"
android:layout_height="wrap_content"
android:button="@null"
android:focusable="true"
android:focusableInTouchMode="true"
android:gravity="center"
android:nextFocusLeft="@+id/tv_show"
android:text="第一" />
<RadioButton
android:id="@+id/l2"
style="@style/TitleButton"
android:layout_width="180dip"
android:layout_height="wrap_content"
android:button="@null"
android:focusable="true"
android:focusableInTouchMode="true"
android:gravity="center"
android:text="第二" />
<RadioButton
android:id="@+id/l3"
style="@style/TitleButton"
android:layout_width="180dip"
android:layout_height="wrap_content"
android:button="@null"
android:focusable="true"
android:focusableInTouchMode="true"
android:gravity="center"
android:text="第三" />
<RadioButton
android:id="@+id/l4"
style="@style/TitleButton"
android:layout_width="180dip"
android:layout_height="wrap_content"
android:button="@null"
android:focusable="true"
android:focusableInTouchMode="true"
android:gravity="center"
android:nextFocusRight="@+id/settings"
android:text="第四" />
</RadioGroup>
<android.support.v4.view.ViewPager
android:id="@+id/main_layout_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal"
android:layout_marginTop="100dp" />
</RelativeLayout>
RadioGroup的样式：定义了选中和未选中radiogroup的背景及颜色的改变。
<style name="TitleButton">
<item name="android:background">@drawable/title_button_selector</item>
<item name="android:textColor">@drawable/title_textcolor_selector</item>
<item name="android:textSize">25sp</item>
</style>
layout1:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="这是第一个界面" />
</LinearLayout>其他的三个布局文件都差不多，就不一一列举了。。。
接下来看 view1的编写：
import android.content.Context;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.LinearLayout;
public class View1 extends LinearLayout {
private Context mContext;
public View1(Context context) {
super(context);
mContext = context;
}
public void initView() {
setLayoutParams(new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT));
setGravity(Gravity.CENTER_HORIZONTAL);
View root = LayoutInflater.from(mContext).inflate(R.layout.layout1,
null);
addView(root);
}
}这里我继承了LinerrLayout,是为了能在mainactivity把我的view填充进去，其他的都比较简单了，后面的几个view也是这样，只不过就是布局不一样而已。
然后是我们的MainActivity:
import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.View;
import android.view.View.OnFocusChangeListener;
import android.widget.RadioButton;
import android.widget.RadioGroup;
public class MainActivity extends Activity {
private View1 v1;
private View2 v2;
private View3 v3;
private View4 v4;
private ArrayList<View> pages = new ArrayList<View>();
private ViewPager centerPager;
private RadioGroup titleGroup;// 标签组
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
v1 = new View1(this);
v2 = new View2(this);
v3 = new View3(this);
v4 = new View4(this);
pages.add(v1);
pages.add(v2);
pages.add(v3);
pages.add(v4); // 添加页面
initView();
initListener();
}
private void initView() {
titleGroup = (RadioGroup) findViewById(R.id.title_group);
titleGroup.check(R.id.l1);
centerPager = (ViewPager) findViewById(R.id.main_layout_pager);
centerPager.setAdapter(new AllPagesAdapter(pages));
// 当前显示第一页
centerPager.setCurrentItem(0);
v1.initView();//加载页面
v2.initView();
v3.initView();
v4.initView();
}
<span style="white-space:pre"> </span>//对radiogroup的焦点监听，进行页面的切换
public void initListener() {
OnFocusChangeListener focusListener = new OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
if (hasFocus) {
int position = (Integer) v.getTag();
centerPager.setCurrentItem(position, true);
}
}
};
for (int i = 0; i < titleGroup.getChildCount(); i++) {
View view = titleGroup.getChildAt(i);
view.setTag(i);
view.setOnFocusChangeListener(focusListener);
}
centerPager.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
if (arg0 < titleGroup.getChildCount()) {
((RadioButton) titleGroup.getChildAt(arg0))
.setChecked(true);
}
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
}适配器代码：
import java.util.ArrayList;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.view.View;
import android.view.ViewGroup;
public class AllPagesAdapter extends PagerAdapter {
private ArrayList<View> views;
public AllPagesAdapter(ArrayList<View> views) {
super();
this.views = views;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((View) object);
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
View child = views.get(position);
container.addView(child);
return child;
}
@Override
public int getCount() {
return views.size();
}
@Override
public boolean isViewFromObject(View arg0, Object arg1) {
// TODO Auto-generated method stub
return arg0 == arg1;
}
@Override
public Parcelable saveState() {
return null;
}
public void dataChanged(ArrayList<View> views) {
this.views = views;
notifyDataSetChanged();
}
}
代码都比较简单，就到这里了，以后还会继续编写一些有关机顶盒的开发的程序。。。。看下效果图：
原文地址：http://blog.csdn.net/a565102223/article/details/41074645
