編輯:關於Android編程
在android開發中會碰到有頂部導航並且下面顯示的內容是一個listview,此時要想實現左右滑動切換頂部導航的選項是不能實現的,因為listview自己消耗橫向滑動事件。因為我可以通過繼承listview,對左右滑動事件進行消耗,不在讓原生的listview處理。
效果圖:

思路就是繼承listview,設置一個GestureDetector監聽滑動手勢,如果左右滑動進行處理調用一個自己寫的左右滑動的接口。
下面是我封裝的一個可以接受左右滑動的listview,其他用法跟普通的listview一樣,可以直接使用:
package com.yasin.libs;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.GestureDetector.OnGestureListener;
import android.widget.ListView;
/*
* 該listview是對左右滑動進行了監聽,
* 我也寫一個OnFlingListener接口,使用該listview的時候通過setOnFlingListener接口即可實現左右滑動時要實現的操作
* */
public class HSlidableListView extends ListView {
Context context;
GestureDetector gestureDetector;
OnFlingListener mListener;
/*
* 設置左右滑動監聽
* */
public void setOnFlingListener(OnFlingListener listener) {
this.mListener = listener;
gestureDetector = new GestureDetector(context, new Gesture(context,
mListener));
}
public HSlidableListView(Context context, AttributeSet attrs) {
super(context, attrs);
this.context = context;
}
public HSlidableListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.context = context;
}
public HSlidableListView(Context context) {
super(context);
this.context = context;
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (gestureDetector.onTouchEvent(ev))
return true;//當左右滑動時自己處理
return super.onTouchEvent(ev);
}
/*
* 滑動監聽
* */
public class Gesture implements OnGestureListener {
Context context;
OnFlingListener mListener;
public Gesture(Context context, OnFlingListener listener) {
this.context = context;
this.mListener = listener;
}
@Override
public boolean onDown(MotionEvent e) {
return false;
}
@Override
public void onShowPress(MotionEvent e) {
}
@Override
public boolean onSingleTapUp(MotionEvent e) {
return false;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
return false;
}
@Override
public void onLongPress(MotionEvent e) {
}
@Override
/**
*
*/
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
if (Math.abs(e1.getX() - e2.getX()) > Math.abs(e1.getY()
- e2.getY())) {//當左右滑動距離大於上下滑動距離時才認為是左右滑
// 左滑
if (e1.getX() - e2.getX() > 100) {
mListener.onLeftFling();
return true;
}
// 右滑
else if (e1.getX() - e2.getX() < -100) {
mListener.onRightFling();
return true;
}
}
return true;
}
}
/*
* 左右滑動時調用的監聽接口
* */
public interface OnFlingListener {
public void onLeftFling();
public void onRightFling();
}
}
使用舉例:
xml布局文件
MainActivity代碼:
package com.yasin.hslidablelistview;
import java.util.ArrayList;
import java.util.List;
import com.yasin.libs.HSlidableListView;
import com.yasin.libs.HSlidableListView.OnFlingListener;
import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.RadioGroup.OnCheckedChangeListener;
public class MainActivity extends Activity {
RadioGroup radioGroup;
RadioButton maintainRB,warmRB;
HSlidableListView listview;
List mData=new ArrayList();
List wData=new ArrayList();
MAdapter mAdapter;
WAdapter wAdapter;
int flag =0 ;//0表示左邊選中,1表示右邊選中
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
private void initView() {
maintainRB = (RadioButton) findViewById(R.id.maintain);
warmRB = (RadioButton) findViewById(R.id.warm);
listview = (HSlidableListView) findViewById(R.id.msg_list);
listview.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView parent, View view,
int position, long id) {
Log.e("yasin","click");
}
});
/*
* 給該listview設置監聽,做出相應操作
* */
listview.setOnFlingListener(new OnFlingListener(){
@Override
public void onLeftFling() {
if(flag == 0){
warmRB.performClick();
flag = 1;
}
}
@Override
public void onRightFling() {
Log.e("y-p","right");
if(flag == 1){
maintainRB.performClick();
flag = 0;
}
}
});
getDataT(1);
radioGroup = (RadioGroup) findViewById(R.id.type);
radioGroup.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
if(checkedId==R.id.maintain){
maintainRB.setTextColor(Color.parseColor("#000000"));
warmRB.setTextColor(Color.parseColor("#ffffff"));
flag = 0;
getDataT(1);
}else if(checkedId==R.id.warm){
maintainRB.setTextColor(Color.parseColor("#ffffff"));
warmRB.setTextColor(Color.parseColor("#000000"));
flag = 1;
getDataT(2);
}
}
});
}
public void getDataT(int flag){
if(flag == 1){
mData.clear();
for(int i=0;i<7;i++){
MaintainSensor m = new MaintainSensor();
m.id = i+"";
m.fname = "養殖"+i+"廠";
m.sname = i+"設備";
m.snum = i+"";
m.desc = "1藥劑更換,包含廢液袋更換和純淨水更換 2.進樣口過濾頭更換 3.傳感器清理 4.太陽板清理";
m.isMaintain = (i%2==0)?"0":"1";
mData.add(m);
}
mAdapter = new MAdapter(MainActivity.this,mData);
listview.setAdapter(mAdapter);
}else{
wData.clear();
for(int i=0;i<7;i++){
WarmMessage w = new WarmMessage();
w.id = i+"";
w.title = "養殖"+i+"廠";
w.content = i+"設備";
w.time = i+"";
wData.add(w);
}
wAdapter = new WAdapter(MainActivity.this,wData);
listview.setAdapter(wAdapter);
}
}
private class MaintainSensor{
String id,fname,snum,sname,desc,isMaintain;
}
private class WarmMessage{
String id,title,content,time;
}
private class MAdapter extends BaseAdapter{
Context mContext;
List data;
public MAdapter(Context c,List m){
this.mContext = c;
this.data = m;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return data.size();
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return data.get(arg0);
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public View getView(int i, View convertView, ViewGroup arg2) {
ViewHolder holder;
if(convertView==null){
convertView = LayoutInflater.from(mContext).inflate(R.layout.maintain_item, null);
holder = new ViewHolder();
holder.changName = (TextView) convertView.findViewById(R.id.chang_name);
holder.sensorName = (TextView) convertView.findViewById(R.id.sensor_name);
holder.desc = (TextView) convertView.findViewById(R.id.maintain_desc);
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
MaintainSensor maint = data.get(i);
holder.changName.setText(maint.fname);
holder.sensorName.setText(maint.sname);
holder.desc.setText(maint.desc);
return convertView;
}
private class ViewHolder{
TextView changName,sensorName,desc;
}
}
private class WAdapter extends BaseAdapter{
Context mC;
List data;
public WAdapter(Context c,List d){
this.mC = c;
this.data = d;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return data.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return data.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int i, View convertView, ViewGroup parent) {
ViewHolder holder;
if(convertView==null){
holder = new ViewHolder();
convertView = LayoutInflater.from(mC).inflate(R.layout.item_warm_msg, null);
holder.title = (TextView) convertView.findViewById(R.id.msg_title);
holder.time = (TextView) convertView.findViewById(R.id.msg_time);
holder.content = (TextView) convertView.findViewById(R.id.msg_content);
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
WarmMessage warm = data.get(i);
holder.title.setText(warm.title);
holder.time.setText(warm.time);
holder.content.setText(warm.content);
return convertView;
}
private class ViewHolder{
TextView title,time,content;
}
}
}
以上就是一個使用范例,有些資源文件我沒有貼出。
PS:左右滑動的事件是由自定義的Listview監聽的,如果你滑動的地方不在該listview上是無法滑動的。(例如你listview中的item只有一條,下面時候空白,你滑動空白時是無法監聽到滑動事件,你需要在該activity或fragment中監聽左右滑動事件)
github全部源碼:https://github.com/yangzhenkun/HSlidableListView
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