看到京东电视app的按钮获取焦点后才加载数据，之前网上没找到好的说法，所以自己实现了记录一下以便后续学习。
主要是按钮获取焦点以后，初始化一个定时器Timer延迟500ms加载数据，如果失去焦点，取消这个定时器就ok了。其实原理很简单，下面是我实现的一个效果。
代码语言：javascript复制package com.longmaster.iptv.health.DoctorP2P.mode;
import android.content.Context;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import com.longmaster.iptv.health.R;
import com.longmaster.iptv.health.common.Constants;
import com.longmaster.iptv.health.widget.MagicTextView.MagicTextView;
import org.VideoWebInterface.DepartmentParam;
import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import cn.longmaster.lmkit.event.MessageProxy;
import cn.longmaster.lmkit.utils.AppLogger;
/**
* Created by yzq on 2017/5/8
*/
public class ButtonAdapter extends RecyclerView.Adapter<ButtonAdapter.MyViewHolder {
private List<DepartmentParam mDepartmentList = new ArrayList< ();
private LayoutInflater mInflater;
private Context mContext;
private boolean mIsLostFocus = false;
private LinearLayoutManager mLinearLayoutManager;
private RecyclerView mRecyclerView;
private TimerTask mTimerTask;
private Timer mTimer;
private boolean isLoadData = true;
public ButtonAdapter(Context context) {
super();
this.mContext = context;
mInflater = LayoutInflater.from(context);
}
public void setLayoutManager(LinearLayoutManager linearLayoutManager, RecyclerView re) {
mLinearLayoutManager = linearLayoutManager;
mRecyclerView = re;
}
public void setDepartmentList(List list) {
mDepartmentList = list;
}
public void setFocus(boolean isFocus) {
mIsLostFocus = isFocus;
}
public void setIsLoadData(boolean isLoadData) {
this.isLoadData = isLoadData;
}
public void clear() {
mDepartmentList.clear();
}
@Override
public int getItemCount() {
return mDepartmentList.size();
}
@Override
public void onBindViewHolder(final MyViewHolder holder, final int position) {
holder.tv.setText(mDepartmentList.get(position).GetDeptName());
holder.tv.setFocusable(true);
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = mInflater.inflate(R.layout.list_class_item, parent, false);
MyViewHolder holder = new MyViewHolder(view);
return holder;
}
class MyViewHolder extends RecyclerView.ViewHolder {
MagicTextView tv;
RelativeLayout mOuterBgRL;
public MyViewHolder(final View view) {
super(view);
RecyclerView.LayoutParams param = (RecyclerView.LayoutParams) itemView.getLayoutParams();
param.height = LinearLayout.LayoutParams.WRAP_CONTENT;
param.width = LinearLayout.LayoutParams.MATCH_PARENT;
itemView.setVisibility(View.VISIBLE);
tv = (MagicTextView) view.findViewById(R.id.class_name);
mOuterBgRL = (RelativeLayout) view.findViewById(R.id.rl_class_outer_bg);
tv.setOnFocusChangeListener(new View.OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus) {
if (hasFocus) {
mOuterBgRL.setBackgroundResource(R.drawable.p2p_select);
if (isLoadData) {
mTimerTask = new TimerTask() {
@Override
public void run() {
int iPosition = getAdapterPosition();
DepartmentParam departmentParam = mDepartmentList.get(iPosition);
MessageProxy.sendMessage(Constants.Message.P2P_SELECTION_DOCTOR_CLASS, iPosition, departmentParam);
}
};
mTimer = new Timer();
mTimer.schedule(mTimerTask, 500);
}
} else {
clearTimer();
if (mIsLostFocus) {
mOuterBgRL.setBackgroundResource(R.drawable.p2p_unselect);
}
}
}
});
tv.setOnKeyListener(new View.OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if (event.getAction() == KeyEvent.ACTION_DOWN) {
int mCurrentSelectPosition = getAdapterPosition();
int mDepartmentCount = mDepartmentList.size();
AppLogger.e("mCurrentSelectPosition ", mCurrentSelectPosition "----" mDepartmentCount);
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_LEFT:
setIsLoadData(true);
setFocus(true);
if (mCurrentSelectPosition == (mLinearLayoutManager.findFirstVisibleItemPosition())) {
mRecyclerView.smoothScrollBy(-400, 0);
}
View view1 = mLinearLayoutManager.findViewByPosition(mCurrentSelectPosition - 1);
if (view1 != null) {
setViewFocus(view1.findViewById(R.id.class_name));
}
return true;
case KeyEvent.KEYCODE_DPAD_RIGHT:
if (mCurrentSelectPosition == mDepartmentCount - 1) {
return true;
}
setIsLoadData(true);
setFocus(true);
if (mCurrentSelectPosition == (mLinearLayoutManager.findLastVisibleItemPosition())) {
mRecyclerView.smoothScrollBy(400, 0);
}
View view = mLinearLayoutManager.findViewByPosition(mCurrentSelectPosition 1);
if (view != null) {
setViewFocus(view.findViewById(R.id.class_name));
}
return true;
case KeyEvent.KEYCODE_BACK:
break;
case KeyEvent.KEYCODE_DPAD_UP:
break;
case KeyEvent.KEYCODE_DPAD_DOWN:
setFocus(false);
mOuterBgRL.setBackgroundResource(R.drawable.p2p_key_down);
break;
}
}
return false;
}
});
}
}
public void setViewFocus(View view) {
view.setFocusable(true);
view.setFocusableInTouchMode(true);
view.requestFocus();
view.requestFocusFromTouch();
}
private void clearTimer() {
if (mTimer != null) {
mTimer.cancel();
}
if (mTimerTask != null) {
mTimerTask.cancel();
}
}
}以上就是本文的全部内容，希望对大家的学习有所帮助。
