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; ListmData=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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