編輯:關於Android編程
有時候,為了實現項目中的需求,完成設計好的用戶交互體驗,不的不把這些View重新改造成自己想要的效果。
Android原生的ListView是不支持左右滑動的,但是看到微信電話本上,聯系人可以左右滑動進行操作的,就通過自己的設想和思路,並加以實現了。
思路:
1.獲取到手指放到屏幕時的x,y位置,並判斷點擊的處於ListView的那個position。
2.判斷滑動的方向,如果是上下方向,touch事件就交給ListView處理;如果是左右方向,就禁止ListView進行滑動。
3.根據手指的移動,來移動選中的View。
4.滑動結束後,把View歸位。
5.通過傳入的監聽器,告訴用戶是左滑動還是右滑動。
效果圖:
重新的ListView的代碼:
package com.example.wz.view; import android.annotation.SuppressLint; import android.content.Context; import android.os.Handler; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewConfiguration; import android.view.WindowManager; import android.widget.AdapterView; import android.widget.ListView; import android.widget.TextView; import com.example.wz.R; import com.example.wz.util.MyLog; import com.example.wz.util.OpenLooper; import com.example.wz.util.OpenLooper.LoopCallback; public class MyListView extends ListView { public MyLog log = new MyLog(this, true); public float screenWidth; public int mTouchSlop; public float density; public MyListView(Context context) { super(context); } public MyListView(Context context, AttributeSet attrs) { this(context, attrs, 0); } public float transleteSpeed = 2f; public OpenLooper openLooper = null; public LoopCallback loopCallback = null; @SuppressWarnings("deprecation") public MyListView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); this.screenWidth = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getWidth(); this.mTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop(); this.density = context.getResources().getDisplayMetrics().density; this.openLooper = new OpenLooper(); this.openLooper.createOpenLooper(); this.loopCallback = new ListLoopCallback(this.openLooper); this.openLooper.loopCallback = this.loopCallback; } public class BodyStatus { public int None = 0, Down = 1, Move = 2, Up = 3, Homing = 4; int state = None; } public BodyStatus bodyStatus = new BodyStatus(); public class RemoveDirection { public int None = 0, Left = 1, Right = 2, Homing_Left = 3, Homing_Right = 4; public int state = None; } public RemoveDirection removeDirection = new RemoveDirection(); public class ListLoopCallback extends LoopCallback { public ListLoopCallback(OpenLooper openLooper) { openLooper.super(); } @Override public void loop(double ellapsedMillis) { if (bodyStatus.state == bodyStatus.Homing) { goHoming((float) ellapsedMillis); } } } public void goHoming(float delta) { float distance = (float) delta * transleteSpeed; if (removeDirection.state == removeDirection.Left) { float currentX = itemView.getScrollX() + distance; if (currentX > screenWidth) { distance = distance - (currentX - screenWidth); } itemView.scrollBy((int) (distance), itemView.getScrollY()); if (itemView.getScrollX() > screenWidth / 2 + 40 * screenWidth / 1080) { t2.setTranslationX(itemView.getScrollX() - screenWidth / 2 - 40 * 3f); } else { t2.setTranslationX(40 * 3f); } } else if (removeDirection.state == removeDirection.Right) { float currentX = itemView.getScrollX() - distance; if (currentX < -screenWidth) { distance = distance - (Math.abs(currentX) - screenWidth); } itemView.scrollBy((int) (-distance), itemView.getScrollY()); if (itemView.getScrollX() < -(screenWidth / 2 + 40 * 3f * 2)) { t1.setTranslationX(-(Math.abs(itemView.getScrollX()) - screenWidth / 2 - 40 * 3f)); } else { t1.setTranslationX(-40 * 3f); } } else if (removeDirection.state == removeDirection.Homing_Left) { float currentX = itemView.getScrollX() - distance; if (currentX < 0) { distance = distance - (Math.abs(currentX)); } itemView.scrollBy((int) (-distance), itemView.getScrollY()); } else if (removeDirection.state == removeDirection.Homing_Right) { float currentX = itemView.getScrollX() + distance; if (currentX > 0) { distance = distance - currentX; } itemView.scrollBy((int) (distance), itemView.getScrollY()); } if (itemView.getScrollX() == 0 || itemView.getScrollX() >= screenWidth || itemView.getScrollX() <= -screenWidth) { openLooper.stop(); if (itemView.getScrollX() >= screenWidth) { mRemoveListener.removeItem(removeDirection, position); } else if (itemView.getScrollX() <= -screenWidth) { mRemoveListener.removeItem(removeDirection, position); } new Handler().postDelayed(new Runnable() { @Override public void run() { itemView.scrollTo(0, itemView.getScrollY()); bodyStatus.state = bodyStatus.None; } }, 300); } } public int touch_down_x; public int touch_down_y; public View itemView; public TextView t1; public TextView t2; public int SNAP_VELOCITY = 800; public int position; @Override public boolean dispatchTouchEvent(MotionEvent event) { int action = event.getAction(); if (action == MotionEvent.ACTION_DOWN) { // addVelocityTracker(event); if (bodyStatus.state != bodyStatus.None) { return super.dispatchTouchEvent(event); } this.touch_down_x = (int) event.getX(); this.touch_down_y = (int) event.getY(); position = pointToPosition(touch_down_x, touch_down_y); if (position == AdapterView.INVALID_POSITION) { return super.dispatchTouchEvent(event); } itemView = getChildAt(position - getFirstVisiblePosition()); t2 = (TextView) itemView.findViewById(R.id.t2); t1 = (TextView) itemView.findViewById(R.id.t1); } else if (action == MotionEvent.ACTION_MOVE) { if (Math.abs(getScrollVelocity()) > SNAP_VELOCITY || (Math.abs(event.getX() - touch_down_x) > mTouchSlop && Math.abs(event.getY() - touch_down_y) < mTouchSlop)) { isSlide = true; } } else if (action == MotionEvent.ACTION_UP) { int velocityX = getScrollVelocity(); if (Math.abs(velocityX) > SNAP_VELOCITY) { if (velocityX > SNAP_VELOCITY) { bodyStatus.state = bodyStatus.Homing; removeDirection.state = removeDirection.Right; openLooper.start(); } else { bodyStatus.state = bodyStatus.Homing; removeDirection.state = removeDirection.Left; openLooper.start(); } } else { if (itemView.getScrollX() >= screenWidth / 2) { bodyStatus.state = bodyStatus.Homing; removeDirection.state = removeDirection.Left; openLooper.start(); } else if (itemView.getScrollX() <= -screenWidth / 2) { bodyStatus.state = bodyStatus.Homing; removeDirection.state = removeDirection.Right; openLooper.start(); } else { if (itemView.getScrollX() < 0) { removeDirection.state = removeDirection.Homing_Right; } else { removeDirection.state = removeDirection.Homing_Left; } bodyStatus.state = bodyStatus.Homing; openLooper.start(); } } recycleVelocityTracker(); isSlide = false; } return super.dispatchTouchEvent(event); } public boolean isSlide = false; @SuppressLint("Recycle") @Override public boolean onTouchEvent(MotionEvent event) { if (isSlide && position != AdapterView.INVALID_POSITION) { requestDisallowInterceptTouchEvent(true); addVelocityTracker(event); int x = (int) event.getX(); int action = event.getAction(); if (action == MotionEvent.ACTION_DOWN) { } else if (action == MotionEvent.ACTION_MOVE) { MotionEvent cancelEvent = MotionEvent.obtain(event); cancelEvent.setAction(MotionEvent.ACTION_CANCEL | (event.getActionIndex() << MotionEvent.ACTION_POINTER_INDEX_SHIFT)); onTouchEvent(cancelEvent); int deltaX = touch_down_x - x; touch_down_x = x; if (itemView.getScrollX() > screenWidth / 2 + 40 * 3f * 2) { t2.setTranslationX(itemView.getScrollX() - screenWidth / 2 - 40 * 3f); } else { t2.setTranslationX(40 * 3f); } if (itemView.getScrollX() < -(screenWidth / 2 + 40 * 3f * 2)) { t1.setTranslationX(-(Math.abs(itemView.getScrollX()) - screenWidth / 2 - 40 * 3f)); } else { t1.setTranslationX(-40 * 3f); } itemView.scrollBy(deltaX, 0); return true; } } return super.onTouchEvent(event); } public RemoveListener mRemoveListener; public void setRemoveListener(RemoveListener removeListener) { this.mRemoveListener = removeListener; } public interface RemoveListener { public void removeItem(RemoveDirection direction, int position); } public VelocityTracker velocityTracker; public void addVelocityTracker(MotionEvent event) { if (velocityTracker == null) { velocityTracker = VelocityTracker.obtain(); } velocityTracker.addMovement(event); } public int getScrollVelocity() { if (velocityTracker != null) { velocityTracker.computeCurrentVelocity(1000); int velocity = (int) velocityTracker.getXVelocity(); return velocity; } return 0; } public void recycleVelocityTracker() { if (velocityTracker != null) { velocityTracker.recycle(); velocityTracker = null; } } }
測試ListView的Activity代碼:
package com.example.wz; import java.util.ArrayList; import android.app.Activity; import android.os.Bundle; import android.util.DisplayMetrics; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.TextView; import com.example.wz.view.MyListView; import com.example.wz.view.MyListView.RemoveDirection; import com.example.wz.view.MyListView.RemoveListener; public class TestListActivity extends Activity { LayoutInflater mInflater; @Override protected void onCreate(Bundle savedInstanceState) { displayMetrics = new DisplayMetrics(); this.getWindowManager().getDefaultDisplay().getMetrics(displayMetrics); super.onCreate(savedInstanceState); setContentView(R.layout.activity_testlist); mInflater = getLayoutInflater(); listView = (MyListView) findViewById(R.id.slideCutListView); showAddressDialog(); } public DisplayMetrics displayMetrics; MyListView listView; public ArrayList<String> items; public void showAddressDialog() { items = new ArrayList<String>() { { add("item...1"); add("item...2"); add("item...3"); add("item...4"); add("item...5"); add("item...6"); add("item...7"); add("item...8"); add("item...9"); add("item...10"); add("item...11"); add("item...12"); add("item...13"); add("item...14"); add("item...15"); add("item...16"); add("item...17"); add("item...18"); add("item...19"); add("item...20"); } }; NearbyRelationAdapter nearbyRelationAdapter = new NearbyRelationAdapter(); listView.setAdapter(nearbyRelationAdapter); listView.setRemoveListener(new RemoveListener() { @Override public void removeItem(RemoveDirection direction, int position) { if (direction.state == direction.Left) { Log.e("A", "left" + "-" + position); } else if (direction.state == direction.Right) { Log.e("A", "right" + "-" + position); } } }); } public class NearbyRelationAdapter extends BaseAdapter { @Override public int getCount() { return items.size(); } @Override public Object getItem(int posotion) { return items.get(posotion); } @Override public long getItemId(int posotion) { return posotion; } @Override public View getView(int position, View convertView, ViewGroup parent) { Holder holder = null; if (convertView == null) { holder = new Holder(); convertView = mInflater.inflate(R.layout.view_menu_item1, null); holder.title = (TextView) convertView.findViewById(R.id.title); holder.o1 = convertView.findViewById(R.id.o1); holder.o1.setTranslationX(-displayMetrics.widthPixels); holder.o2 = convertView.findViewById(R.id.o2); holder.o2.setTranslationX(displayMetrics.widthPixels); convertView.setTag(holder); } else { holder = (Holder) convertView.getTag(); } holder.title.setText(items.get(position)); convertView.scrollTo(0, convertView.getScrollY()); return convertView; } class Holder { TextView title; View o1, o2; } } }
ListView布局文件:
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@android:color/darker_gray" > <com.example.wz.view.MyListView android:id="@+id/slideCutListView" android:layout_width="match_parent" android:layout_height="match_parent" android:cacheColorHint="@android:color/transparent" android:listSelector="@android:color/transparent" > </com.example.wz.view.MyListView> <TextView android:layout_width="1dp" android:layout_height="match_parent" android:layout_centerHorizontal="true" android:background="#0099cd" /> </RelativeLayout>
ListView 的Item布局:
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="#fff" > <RelativeLayout android:id="@+id/o1" android:layout_width="match_parent" android:layout_height="60dp" android:background="#ff0000" > <TextView android:id="@+id/t1" android:layout_width="80dp" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:layout_centerVertical="true" android:gravity="center" android:padding="10dp" android:text="刪除" android:textColor="#99000000" android:textSize="18sp" /> </RelativeLayout> <RelativeLayout android:id="@+id/o2" android:layout_width="match_parent" android:layout_height="60dp" android:background="#660099cd" > <TextView android:id="@+id/t2" android:layout_width="80dp" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:gravity="center" android:padding="10dp" android:text="編輯" android:textColor="#99000000" android:textSize="18sp" /> </RelativeLayout> <RelativeLayout android:id="@+id/r1" android:layout_width="match_parent" android:layout_height="60dp" android:background="#fff" > <TextView android:id="@+id/title" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" android:gravity="center_vertical" android:textColor="#99000000" android:textSize="18sp" /> </RelativeLayout> </RelativeLayout>
代碼中用到的其他的類,在上一篇文章中有: http://www.jb51.net/article/83822.htm
轉載來自:http://blog.csdn.net/qxs965266509
以上就是本文的全部內容,希望對大家的學習有所幫助。
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